A two-stage parallel projection support device for taking periapical radiographs

Abstract

The present invention belongs to the field of medical devices, and in particular relates to a two-stage parallel projection bracket device for taking periapical films by using parallel projection technology, which is characterized in that: it includes a tube fixing ring and a disposable film holding clip, the fixing ring is provided with a ring body and N U-shaped grooves, N≥1; the U-shaped groove is provided on the outer surface of the ring body; the disposable film holding clip includes an extension part, a connecting rod, a bite part and a film holding part, the film holding part is connected to one end of the bite part, the two ends of the connecting rod are respectively vertically connected to the extension part and the other end of the bite part, the extension part is parallel to the bite part and the extension direction is opposite; one end of the connecting rod is vertically connected to the extension part, and the other end of the extension part extends into the U-shaped groove, so that the fixing ring and the disposable film holding clip are fixedly connected into one body. The device of the present invention uses parallel projection technology to fix the relative position and angle of the tube and the tooth to be photographed, and only the disposable film holding clip needs to be replaced during shooting, which reduces the cost of disinfection or consumables on the one hand, and reduces the difficulty of shooting technology and improves accuracy on the other hand.

Description

Technical Field

[0001] The invention belongs to the field of medical instruments, and in particular relates to a two-section parallel projection support device for taking periapical films. Background Art

[0002] Periapical radiograph is the most commonly used imaging diagnostic technology in oral clinical work, and is widely used in daily diagnosis and treatment in endodontics, periodontics, alveolar surgery, restoration and implantology, and even orthodontics.

[0003] The shooting techniques of periapical radiographs mainly include two types: angle bisector technique and parallel projection technique. Among them, the angle bisector technique is widely used, and has the advantages of not requiring the assistance of additional devices and only requiring the patient's fingers or film holders to fix the film; the disadvantages are high technical difficulty, unstable shooting quality, and high deformation and distortion rate. Although the parallel projection technique has low technical difficulty, stable shooting quality, and low deformation and distortion rate, it requires a special parallel projection bracket, which increases the cost of consumables and disinfection, and is therefore relatively less used.

[0004] With the rapid development of oral treatment technology, especially the rise of implant technology and orthodontic technology, the requirements for image projection technology are also increasing. In particular, the shooting of periapical films after implant surgery and before and after orthodontic anchorage surgery requires the elimination of deformation and distortion as much as possible to restore the parallel structure of the implant thread and the true width of the alveolar bone between teeth. In addition, periodontal, pediatric, and endodontic clinicians are also increasingly emphasizing the parallel shooting of periapical films. On the other hand, from the perspective of hospital infection control, there is a certain risk of infection control when the patient's fingers press and the medical staff's fingers enter the patient's mouth. Parallel projection technology can avoid this problem well.

[0005] However, due to the technical problems of parallel projection technology itself, the price of a set of parallel projection brackets on the market is several times more expensive than the price of periapical films, and the cost of disinfecting a set of brackets often exceeds the charging price. Therefore, the development and use of parallel projection technology in practical applications are limited. In addition, the tube ring of most parallel projection brackets is in contact with the tube but not fixed, so it is easy to move when the tube is placed, affecting the imaging quality. Repeated disinfection of parallel projection brackets can also easily cause deformation and aging of the bracket, affecting its use. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a two-stage parallel projection bracket device for taking periapical films, which is applied to the parallel projection technology when taking periapical films. On the one hand, it reduces the amount of disposable consumables, and on the other hand, it fixes the tube ring, making the shooting more stable, without the need for frequent disinfection, and delaying aging, thereby increasing the available time.

[0007] The present invention solves the above technical problems and provides a two-stage parallel projection support device for taking periapical films, which is characterized by: comprising a tube fixing ring and a disposable film holding clamp, the fixing ring being provided with a ring body and N U-shaped grooves, N≥1; the U-shaped groove being provided on the outer surface of the ring body; the disposable film holding clamp comprising an extension part, a connecting rod, an occlusal part and a film holding part, the film holding part being connected to one end of the occlusal part, the two ends of the connecting rod being vertically connected to the extension part and the other end of the occlusal part respectively, the extension part being parallel to the occlusal part and extending in opposite directions; one end of the connecting rod being vertically connected to the extension part, the other end of the extension part extending into the U-shaped groove, so that the fixing ring and the disposable film holding clamp are fixedly connected as a whole.

[0008] The tube fixing ring is an X-ray tube fixing ring. X-ray is an electromagnetic wave with a very short wavelength, a photon. The wavelength of X-ray used in diagnosis is 0.08-0.31 angstroms (1 angstrom = 0.1 nanometers = 10 to the -10th power of meters), and is used as one of the auxiliary examination methods in medicine.

[0009] The tube fixing ring is a fixing device that does not touch the human body and can be used repeatedly. The disposable film holder enters the oral cavity and is a disposable device for single use. It is a Class II medical device and a disposable consumable. It is replaced once per person. This device not only meets the requirements of hospital infection control, but also saves consumables and disinfection costs. The film holder is used to fix the film.

[0010] The X-ray tube fixing ring is an annular ring, the tube fixing ring is an X-ray tube fixing ring, annular ring, the inner diameter of the ring = 68-84mm, the ring thickness ≥ 3mm, and the ring width is 10-20mm; in the optimization scheme, the inner diameter of the ring = 68mm, the ring thickness 3mm, and the ring width 15mm. The size of the ring matches the outer diameter of the X-ray tube so that it is fixed on the outer edge of the tube. The size of the inner diameter of the fixing ring is important, and the appropriate size makes the shooting angle consistent, thereby improving the accuracy.

[0011] The U-shaped groove is provided with a groove concave point and two L-shaped arms, the groove concave point is arranged at the center point of the U-shaped bottom end, and the two L-shaped arms are symmetrically arranged with the groove concave point to form a U shape, and the U-shaped groove is fixedly connected to the fixing ring at the groove concave point.

[0012] The U-shaped groove and the ball tube fixing ring can be made as one piece, completely fixed and unable to move; or they can be installed and adjusted by bolt movable type.

[0013] The length of the U-shaped groove is 10-20 mm, and the inner diameter of the groove is 3-10 mm; in the optimized solution, the length of the U-shaped groove is 15 mm, the inner diameter of the groove is 7 mm, and the groove concave point is 5.8 mm high when measured from the starting point.

[0014] The extension part is provided with a built-in slide rail in the longitudinal direction, and a built-in positioning protrusion is provided on the inner surface of the U-shaped groove in the longitudinal direction. The size of the built-in positioning protrusion matches the built-in slide rail. When in use, the built-in positioning protrusion is embedded in the built-in slide rail and slides relative to the built-in slide rail.

[0015] On the one hand, the disposable film holder is connected to the tube fixing ring through the fixed connection function of the built-in slide rail and the built-in positioning protrusion; on the other hand, the distance between the photo and the camera can be increased or shortened, which is convenient for shooting and observation.

[0016] The built-in positioning protrusion is in the shape of a triangular prism, and its size matches the built-in slide rail of the extension part, so that the tube fixing ring is connected to the disposable film holding clip in a fixed direction; the built-in positioning protrusion in the U-shaped groove is equal in length to the U-shaped groove. The triangular prism is a protrusion on the inner wall of the groove, and can also be made integrally with the inner wall of the groove.

[0017] The built-in slide rail is 10-20mm wide, 1-3mm long, and 0.5-1.5mm high. In the optimized solution, it is 1.5mm long, 15mm wide, and 0.7mm high, and its size matches the shape and size of the built-in positioning convex on the U-shaped groove.

[0018] The built-in positioning protrusion is set at the 0° and 90° positions relative to the concave point of the U-shaped groove. The position of the built-in positioning protrusion in the U-shaped groove enables the film holding part to be located at the center of the fixing ring, that is, the center of the film projection, after the connection is completed. The reason is that the extension rails coupled with it are set in these two directions to ensure that the disposable film holding clip and the fixing ring are only fixed in the correct position and can slide after the connection is completed.

[0019] The N=8, that is, the number of U-shaped grooves is 8.

[0020] The eight U-shaped grooves are respectively located in eight directions of 0°, 60°, 90°, 120°, 180°, 240°, 270°, and 300° directly above the center of the fixing ring.

[0021] The orientation of the U-shaped groove is related to the oral anatomical structure. 0° is used to shoot the lower anterior teeth, 180° is used to shoot the upper anterior teeth; 60° is used to shoot the left mandibular posterior teeth, 120° is used to shoot the left maxillary posterior teeth; 240° is used to shoot the right maxillary posterior teeth, 300° is used to shoot the right mandibular posterior teeth; 90° is used to shoot the crown of the left posterior teeth, and 270° is used to shoot the crown of the right posterior teeth.

[0022] The extension part is a rod-shaped long cylinder with a length of 50-100 mm and a cross-sectional diameter of 3-10 mm, and in the optimized solution, the length is 80 mm and the cross-sectional diameter is 5 mm. The outer diameter of the extension part is equal to the inner diameter of the U-shaped groove.

[0023] The connection between the occlusal part and the film holding part, the extension part and the connecting rod, or the connecting rod and the occlusal part is a movable connection or an integrated fixed connection. In the present invention, different connection modes can be selected between the film holding part and the occlusal part, or between the occlusal part and the connecting rod according to the requirements of anterior teeth and posterior teeth photography.

[0024] When the occlusal part, the connecting rod and the extension part are connected in an integrated manner, it is suitable for photographing the front teeth; photographing the upper and lower teeth only requires switching the U-shaped grooves in which they are located, with a 0° U-shaped groove photographing the lower front teeth and a 180° U-shaped groove photographing the upper front teeth.

[0025] The anterior teeth occlusal part is a rectangular block with dimensions of 10-20 mm in length, 20-40 mm in width and 7-15 mm in height, and 10 mm in length, 30 mm in width and 7 mm in height in the optimized solution. The anterior teeth group film holder in the present invention is integrally formed, and when photographing the upper anterior teeth, the free end is upward, and when photographing the lower anterior teeth, the free end is downward, and is respectively connected to the U-shaped grooves of 0° and 180° of the tube fixing ring, and then the patient is asked to bite the occlusal part with the upper and lower anterior teeth.

[0026] The connection between the film holding part and the occlusal part, and the movably connected connection between the occlusal part and the connecting rod, that is, the split type in which the film holding part can rotate up and down, can be suitable for posterior teeth photography.

[0027] The film holding part is composed of two sheet structures relatively fitted together. According to different shooting methods of front teeth and back teeth, the film holding part is the front teeth film holding part or the back teeth film holding part.

[0028] The dimensions of the two sheet structures of the front teeth holding part are respectively 15-20mm long, 1-2mm wide, 30-40mm high and 15-20mm long, 1-2.5mm wide, 20-35mm high, and 16mm long, 1mm wide, 35mm high and 16mm long, 1mm wide, 20mm high in the optimization scheme; the reserved gap between the two sheet structures is ≤0.3mm at the narrowest part and 1-2.5mm at the widest part; in the optimization scheme, the narrowest part is 0.2mm and the widest part is 1.5mm. One end of the upper and lower ends is fixed and sealed, and the other end is free (free end) for inserting the tooth piece.

[0029] The sheet structure is a square block or a rectangular block, and the tooth piece is put into the gap between the two blocks and clamped to fix it.

[0030] The tablet holding part is provided with a posterior teeth tablet holding part body, a posterior teeth tablet holding part slot and a posterior teeth tablet holding part connecting rod. The posterior teeth tablet holding part slot is transversely arranged on an outer surface of the sheet-like structure, and one end of the posterior teeth tablet holding part connecting rod is connected to the sheet-like structure; the end of the posterior teeth tablet holding part connecting rod is provided with a posterior teeth tablet holding part connecting rod end expansion; the occlusal part is provided with a front end groove of the posterior teeth occlusal part, an internal guide rail of the posterior teeth occlusal part and a claw type at the end of the posterior teeth occlusal part, the front end groove of the posterior teeth occlusal part is arranged at the front end of the occlusal part, and the internal guide rail of the posterior teeth occlusal part is provided at the inner end of the posterior teeth occlusal part. The rail is set through the center of the occlusal part; the claw at the end of the posterior teeth occlusal part is set inside the rear end of the occlusal part and is connected to the internal guide rail of the posterior teeth occlusal part; the shape and size of the groove at the front end of the posterior teeth occlusal part are matched with the shape and size of the slot of the posterior teeth holding part, and the claw at the end of the posterior teeth occlusal part is matched with the swollen shape of the end of the connecting rod of the posterior teeth holding part; when connected, the connecting rod of the posterior teeth holding part is inserted into the internal guide rail of the posterior teeth occlusal part and is fixed with the claw at the end of the posterior teeth occlusal part, so that the holding part at the other end can be rotated.

[0031] The front end groove of the posterior teeth occlusal part is engaged with the slot of the posterior teeth holding part to ensure that the holding part can be inserted into the occlusal part after rotating up and down to the correct position for fixing. The claw at the end of the posterior teeth occlusal part is used to clamp the expansion at the end of the connecting rod of the posterior teeth holding part so that it will not fall off the track during rotation.

[0032] The minimum diameter of the claw at the end of the posterior teeth occlusal part is consistent with the diameter of the connecting rod of the posterior teeth holding part, so that the posterior teeth holding part can rotate flexibly in the slide rail. The minimum diameter of the claw at the end of the posterior teeth occlusal part is smaller than the expansion at the end of the connecting rod of the posterior teeth holding part, so that the holding part will not fall out after connection. The connecting rod of the posterior teeth holding part is inserted into the internal guide rail of the posterior teeth occlusal part and can rotate.

[0033] The posterior teeth occlusal part is connected to the posterior teeth holding part in a docking structure. The dimensions of the posterior teeth occlusal part are 21-30mm in length, 20-30mm in width, and 6-16mm in height. In the optimized solution, the dimensions are 21mm in length, 20mm in width, and 6mm in height.

[0034] The dimensions of the front end groove of the posterior teeth occlusal part are 21-30mm in length (consistent with the occlusal length), 0.5-1mm in width (consistent with the width of the slot of the posterior teeth holding part), and 0.5-1mm in height (consistent with the height of the slot of the posterior teeth holding part). In the optimized scheme, it is 25mm in length, 0.7mm in width, and 0.8mm in height. The internal guide rail of the posterior teeth occlusal part is 20-30mm in length (consistent with the length of the connecting rod of the posterior teeth holding part), and has a cross-sectional diameter of 2-3.5mm (≥the cross-sectional diameter of the connecting rod of the posterior teeth holding part). In the optimized scheme, the internal guide rail of the posterior teeth occlusal part is 20mm in length and 2mm in cross-sectional diameter. The claw at the end of the posterior teeth occlusal part is a fixing part, with a minimum diameter of 1.6-3mm (consistent with the diameter of the connecting rod of the posterior teeth holding part) and a maximum diameter of 2-3.5mm (consistent with the expansion of the end of the connecting rod of the posterior teeth holding part). In the optimized scheme, the minimum diameter is 1.6mm and the maximum diameter is 2mm.

[0035] The posterior teeth holding part is provided with a posterior teeth holding part body, a posterior teeth holding part slot and a posterior teeth holding part connecting rod. The two sheet structures of the body are respectively 25-35mm long, 1-2mm wide, 20-35mm high and 25-35mm long, 1-2.5mm wide, 15-30mm high. The reserved gap between the two sheet structures is ≤0.3mm at the narrowest point and 1-2.5mm at the widest point. One end of the upper and lower ends is fixed and sealed, and the other end is free (free end) for inserting the tooth piece.

[0036] The dimensions of the slot of the posterior tooth holding part are 25-35mm long, 0.5-1mm wide, and 0.5-1mm high. The connecting rod of the posterior tooth holding part is 20-30mm long, with a cross-sectional diameter of 1.6-3mm. The fixed end of the connecting rod is a frustum with an upper diameter of 2-3.5mm (larger than the cross-sectional diameter), a lower diameter of 1.6-3mm (equal to the cross-sectional diameter), and a height of 1-2mm.

[0037] The posterior teeth holding part and the occlusal part are connected by a slot, and the slot method can be a bolt connection method, an embedded connection method, etc. The holding part can rotate up and down. When photographing the upper posterior teeth, the free end of the rotation is upward, and the upper posterior teeth on the left and right sides are respectively connected to the U-shaped grooves of 60° and 300° of the tube fixing ring. When photographing the lower posterior teeth, the free end of the rotation is downward, and the lower posterior teeth on the left and right sides are respectively connected to the U-shaped grooves of 120° and 240° of the tube fixing ring.

[0038] Because the projection frame required to shoot the left and right posterior teeth has to turn around the corners of the patient's mouth, the directions of the corners on both sides are axially symmetrical. This axially symmetrical deformation can be achieved by rotating the film holding part up and down, thereby reducing production costs and the time cost of selecting parts during shooting. The posterior teeth need to be made rotatable.

[0039] The parallel projection support devices described in the present invention are all made of hard plastic plates, have no elasticity and flexibility, are stably fixed, and prevent shape deformation from causing projection angle deviation.

[0040] The device of the present invention has a delicate and flexible structure, small deformation, and complies with the principle of parallel projection technology. The invention uses hard plastic as the material, and the X-ray can penetrate completely, without generating artifacts and affecting the quality of the photo. The film holder that contacts the patient's mouth is disposable, one person per use, hygienic and safe, and meets the requirements of hospital infection control. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A front view of the ball tube fixing ring of the present invention

[0042] Figure 2 A side view of the ball tube fixing ring in the present invention

[0043] Figure 3 A top view of the ball tube fixing ring in the present invention

[0044] Figure 4 A side view of the disposable film holder for anterior teeth in the present invention

[0045] Figure 5 The side view of the disposable film holder for posterior teeth in the present invention

[0046] Figure 6 The exploded side view of the disposable film holder for posterior teeth in the present invention

[0047] Figure 7 A top view of the disposable film holder for anterior teeth in the present invention

[0048] Figure 8 A top view of the disposable film holder for posterior teeth in the present invention

[0049] Fig. 9 This is an exploded top view of the disposable film holder for posterior teeth in the present invention.

[0050] Fig.10 This is a front view of the disposable film holder for anterior teeth in the present invention.

[0051] Fig.11 This is a front view of the disposable film holder for posterior teeth in the present invention.

[0052] Fig.12 This is an exploded front view of the disposable film holder for posterior teeth in the present invention.

[0053] Fig.13 The three-dimensional model diagram of the anterior tooth kit assembly is taken in the present invention

[0054] Fig.14 The three-dimensional model diagram of the back tooth set assembly is taken in the present invention

[0055] Fig.15 For the present invention, the upper front teeth pattern is taken

[0056] Fig.16 The left lower posterior teeth pattern is taken for the present invention

[0057] Fig.17 The U-shaped groove structure diagram of the present invention

[0058] Among them, the specific symbols in the figure are:

[0059] 1. Ball tube fixing ring, 2. U-shaped groove, 3. U-shaped groove built-in positioning convex, 4. Extension part, 5. Extension slide rail, 6. Occlusal part (6-1. Anterior teeth occlusal part, 6-2. Posterior teeth occlusal part), 7. Sheet holding part (7-1. Anterior teeth sheet holding part, 7-2. Posterior teeth sheet holding part), 8. Groove concave point, 9. Front end groove of posterior teeth occlusal part, 10. Internal guide rail of posterior teeth occlusal part, 11. Claw type at the end of posterior teeth occlusal part, 12. Connecting rod, 13. Gap, 14. End expansion of connecting rod of posterior teeth sheet holding part, 15. Connecting rod of posterior teeth sheet holding part, 16. Slot of posterior teeth sheet holding part, 17. Anterior teeth, 18. Ball tube, 19. Posterior teeth, 20. Film, 22. Palatal side, 23. Lingual side DETAILED DESCRIPTION

[0060] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. When in use, the present invention uses a front teeth group or a back teeth group film holder according to the shooting position.

[0061] Example 1

[0062] A two-stage parallel projection support device for taking periapical films comprises a tube fixing ring and a disposable film holding clip, wherein the fixing ring is provided with a ring body and N U-shaped grooves, N=8; the U-shaped grooves are arranged on the outer surface of the ring body; the disposable film holding clip comprises an extension part, a connecting rod, a bite part and a film holding part, wherein the film holding part is connected to one end of the bite part, and the two ends of the connecting rod are respectively vertically connected to the extension part and the other end of the bite part, and the extension part is parallel to the bite part and extends in opposite directions; one end of the connecting rod is vertically connected to the extension part, and the other end of the extension part extends into the U-shaped groove, so that the fixing ring and the disposable film holding clip are fixedly connected as a whole.

[0063] The tube fixing ring is an X-ray tube fixing ring. X-ray is an electromagnetic wave with a very short wavelength, a photon. The wavelength of X-ray used in diagnosis is 0.08-0.31 angstroms (1 angstrom = 0.1 nanometers = 10 to the -10th power meter), and is used as one of the auxiliary examination methods in medicine.

[0064] The X-ray tube fixing ring is in the shape of a ring, with an inner diameter of 68mm, a thickness of 3mm, and a width of 15mm. The size of the ring matches the outer diameter of the X-ray tube, so that it is fixed on the outer edge of the tube. The inner diameter of the fixing ring is important, and the appropriate size makes the shooting angle consistent, thereby improving the accuracy.

[0065] The U-shaped groove is provided with a groove concave point and two L-shaped arms. The groove concave point is located at the center point of the bottom end of the U-shape. The two L-shaped arms are symmetrically arranged with the groove concave point to form a U shape. The U-shaped groove is fixedly connected to the fixing ring at the groove concave point. N=8, that is, the U-shaped groove is 8 U-shaped grooves. The 8 U-shaped grooves are respectively located in 8 directions of 0°, 60°, 90°, 120°, 180°, 240°, 270°, and 300° directly above the center of the fixing ring.

[0066] The orientation of the U-shaped groove is related to the oral anatomical structure. 0° is used to shoot the lower anterior teeth, 180° is used to shoot the upper anterior teeth; 60° is used to shoot the left mandibular posterior teeth, 120° is used to shoot the left maxillary posterior teeth; 240° is used to shoot the right maxillary posterior teeth, 300° is used to shoot the right mandibular posterior teeth; 90° is used to shoot the crown of the left posterior teeth, and 270° is used to shoot the crown of the right posterior teeth.

[0067] The U-shaped groove and the ball tube fixing ring can be made as one piece, completely fixed and immovable; or they can be installed and adjusted by bolts. The length of the U-shaped groove is 7mm, the inner diameter of the groove is 3mm, the length is the inner diameter of the groove + 4mm, and the height is the inner diameter of the groove + 0.8mm.

[0068] The extension part is provided with a built-in slide rail in the longitudinal direction, and a built-in positioning protrusion is provided on the inner surface of the U-shaped groove in the longitudinal direction. The size of the built-in positioning protrusion matches the built-in slide rail. When in use, the built-in positioning protrusion is embedded in the built-in slide rail and slides relative to the built-in slide rail.

[0069] The built-in positioning protrusion is in the shape of a triangular prism, and its size matches the built-in slide rail of the extension part, so that the tube fixing ring is connected to the disposable film holding clip in a fixed direction; the built-in positioning protrusion in the U-shaped groove is equal to the length of the U-shaped groove. The triangular prism is a protrusion on the inner wall of the groove, and can also be made integrally with the inner wall of the groove. The built-in slide rail is 1.5mm long, 15mm wide and 0.7mm high, and its size matches the shape and size of the built-in positioning protrusion on the U-shaped groove.

[0070] The built-in positioning protrusion is set at the 0° and 90° positions relative to the concave point of the U-shaped groove. The position of the built-in positioning protrusion in the U-shaped groove enables the film holding part to be located at the center of the fixing ring, that is, the center of the film projection, after the connection is completed. The reason is that the extension rails coupled with it are set in these two directions to ensure that the disposable film holding clip and the fixing ring are only fixed in the correct position and can slide after the connection is completed.

[0071] The extension part is a rod-shaped long cylinder with a size of 80mm in length and a cross-sectional diameter of 5mm. The outer diameter of the extension part is smaller than the inner diameter of the U-shaped groove. The holding part consists of two sheet structures that fit together relatively, with dimensions of 16mm in length, 1mm in width, 35mm in height and 16mm in length, 2.5mm in width, and 20mm in height respectively. The reserved gap between the two sheet structures is 0.2mm at the narrowest point and 1.5mm at the widest point; one end of the upper and lower ends is fixed and sealed, and the other end is free (free end) for inserting the tooth piece. The sheet structure is a square block or a rectangular block, and the tooth piece is placed in the gap between the two blocks, and the tooth piece is clamped to fix it.

[0072] The biting part and the sheet holding part, the extending part and the connecting rod, or the connecting rod and the biting part are connected in an integrated fixed manner.

[0073] The film holder of the anterior teeth group is integrally formed, which is suitable for photographing the anterior teeth. To photograph the upper and lower teeth, you only need to convert the U-shaped grooves where they are located; when photographing the upper anterior teeth, the free end is upward, and when photographing the lower anterior teeth, the free end is downward, respectively connected to the 0° and 180° U-shaped grooves of the tube fixing ring, and then ask the patient to bite the occlusal part of the upper and lower anterior teeth. The occlusal part of the anterior teeth is a rectangular block with a size of 10mm in length, 30mm in width and 7mm in height. The parallel projection bracket device described in the present invention is a hard plastic plate, which has no elasticity and yieldability, has stable retention, and prevents morphological deformation from causing projection angle deviation.

[0074] Example 2

[0075] A two-stage parallel projection support device for taking periapical films comprises a tube fixing ring and a disposable film holding clip, wherein the fixing ring is provided with a ring body and N U-shaped grooves, N=8; the U-shaped grooves are arranged on the outer surface of the ring body; the disposable film holding clip comprises an extension part, a connecting rod, a bite part and a film holding part, wherein the film holding part is connected to one end of the bite part, and the two ends of the connecting rod are respectively vertically connected to the extension part and the other end of the bite part, and the extension part is parallel to the bite part and extends in opposite directions; one end of the connecting rod is vertically connected to the extension part, and the other end of the extension part extends into the U-shaped groove, so that the fixing ring and the disposable film holding clip are fixedly connected as a whole.

[0076] The tube fixing ring is an X-ray tube fixing ring. X-ray is an electromagnetic wave with a very short wavelength, a photon. The wavelength of X-ray used in diagnosis is 0.08-0.31 angstroms (1 angstrom = 0.1 nanometers = 10 to the -10th power meter), and is used as one of the auxiliary examination methods in medicine.

[0077] The X-ray tube fixing ring is in the shape of a ring, with an inner diameter of 75mm, a thickness of 3mm or more, and a width of 18mm. The ring size matches the outer diameter of the X-ray tube so that it is fixed on the outer edge of the tube. The inner diameter of the fixing ring is important, and the appropriate size makes the shooting angle consistent, thereby improving the accuracy.

[0078] The U-shaped groove is provided with a groove concave point and two L-shaped arms. The groove concave point is located at the center point of the bottom end of the U-shape. The two L-shaped arms are symmetrically arranged with the groove concave point to form a U shape. The U-shaped groove is fixedly connected to the fixing ring at the groove concave point. N=8, that is, the U-shaped groove is 8 U-shaped grooves. The 8 U-shaped grooves are respectively located in 8 directions of 0°, 60°, 90°, 120°, 180°, 240°, 270°, and 300° directly above the center of the fixing ring.

[0079] The orientation of the U-shaped groove is related to the oral anatomical structure. 0° is used to shoot the lower anterior teeth, 180° is used to shoot the upper anterior teeth; 60° is used to shoot the left mandibular posterior teeth, 120° is used to shoot the left maxillary posterior teeth; 240° is used to shoot the right maxillary posterior teeth, 300° is used to shoot the right mandibular posterior teeth; 90° is used to shoot the crown of the left posterior teeth, and 270° is used to shoot the crown of the right posterior teeth.

[0080] The U-shaped groove and the ball tube fixing ring can be made as one piece, completely fixed and immovable; or they can be installed and adjusted by bolts. The length of the U-shaped groove is 10mm, the inner diameter of the groove is 7mm, and the height measured from the concave point of the groove is 7.8mm.

[0081] The extension part is provided with a built-in slide rail in the longitudinal direction, and a built-in positioning protrusion is provided on the inner surface of the U-shaped groove in the longitudinal direction. The size of the built-in positioning protrusion matches the built-in slide rail. When in use, the built-in positioning protrusion is embedded in the built-in slide rail and slides relative to the built-in slide rail.

[0082] The built-in positioning protrusion is triangular in shape, and its size matches the built-in slide rail of the extension part, so that the tube fixing ring is connected to the disposable film holding clip in a fixed direction; the built-in positioning protrusion in the U-shaped groove is equal to the length of the U-shaped groove. The triangular shape is a protrusion on the inner wall of the groove, and can also be made integrally with the inner wall of the groove. The built-in slide rail is 1.5mm long, 15mm wide and 0.7mm high, and its size matches the shape and size of the built-in positioning protrusion on the U-shaped groove. The built-in slide rail is 10mm wide, 1mm long and 0.5mm high, and its size matches the shape and size of the built-in positioning protrusion on the U-shaped groove.

[0083] The built-in positioning protrusion is set at the 0° and 90° positions relative to the concave point of the U-shaped groove. The position of the built-in positioning protrusion in the U-shaped groove enables the film holding part to be located at the center of the fixing ring, that is, the center of the film projection, after the connection is completed. The reason is that the extension rails coupled with it are set in these two directions to ensure that the disposable film holding clip and the fixing ring are only fixed in the correct position and can slide after the connection is completed.

[0084] The extension part is a rod-shaped long cylinder with a length of 50 mm and a cross-sectional diameter of 3. The outer diameter of the extension part is smaller than the inner diameter of the U-shaped groove.

[0085] The connection between the occlusal part and the film holding part, the extension part and the connecting rod, or the connecting rod and the occlusal part is a movable connection. When the connection between the film holding part and the occlusal part, and the occlusal part and the connecting rod are a movable connection, that is, the film holding part can be rotated up and down, which is suitable for posterior teeth photography.

[0086] The support device for photographing the posterior teeth is provided with a posterior teeth holding part body, a posterior teeth holding part slot and a posterior teeth holding part connecting rod in the holding part of the film. The posterior teeth holding part slot is transversely arranged on an outer surface of the sheet-like structure, and one end of the posterior teeth holding part connecting rod is connected to the sheet-like structure; the end of the posterior teeth holding part connecting rod is provided with a posterior teeth holding part connecting rod end expansion; the occlusal part is provided with a front end groove of the posterior teeth occlusal part, an internal guide rail of the posterior teeth occlusal part and a claw type at the end of the posterior teeth occlusal part, the front end groove of the posterior teeth occlusal part is arranged at the front end of the occlusal part, and the posterior teeth occlusal part is provided with a claw type at the end of the occlusal part. The internal guide rail of the occlusal part is arranged through the center of the occlusal part; the claw at the end of the posterior teeth occlusal part is arranged inside the rear end of the occlusal part and is connected to the internal guide rail of the posterior teeth occlusal part; the shape and size of the groove at the front end of the posterior teeth occlusal part are matched with the shape and size of the slot of the posterior teeth holding part, and the claw at the end of the posterior teeth occlusal part is matched with the swollen shape at the end of the connecting rod of the posterior teeth holding part; when connected, the connecting rod of the posterior teeth holding part is inserted into the internal guide rail of the posterior teeth occlusal part and is fixed with the claw at the end of the posterior teeth occlusal part, so that the holding part at the other end can be rotated.

[0087] The front end groove of the posterior teeth occlusal part is engaged with the slot of the posterior teeth holding part to ensure that the holding part can be inserted into the occlusal part after rotating up and down to the correct position for fixing. The claw at the end of the posterior teeth occlusal part is used to clamp the expansion at the end of the connecting rod of the posterior teeth holding part so that it will not fall off the track during rotation.

[0088] The minimum diameter of the claw at the end of the posterior teeth occlusal part is consistent with the diameter of the connecting rod of the posterior teeth holding part, so that the posterior teeth holding part can rotate freely in the slide rail. The minimum diameter of the claw at the end of the posterior teeth occlusal part is smaller than the expansion at the end of the connecting rod of the posterior teeth holding part, so that the holding part will not fall out after connection. The connecting rod of the posterior teeth holding part is inserted into the internal guide rail of the posterior teeth occlusal part and can rotate.

[0089] The posterior teeth occlusal part is connected to the posterior teeth holding part in a docking structure. The dimensions of the posterior teeth occlusal part are 21mm long, 20mm wide and 6mm high. The "posterior teeth holding part slot" is as described above, and the position is shown in Figure 6 / Fig. 9 / Fig.12 Example 16.

[0090] The dimensions of the front end groove of the posterior tooth occlusal part are 21-30mm in length (consistent with the length of the occlusal part), 0.5-1mm in width (consistent with the width of the slot of the posterior tooth holding part), and 0.5-1mm in height (consistent with the height of the slot of the posterior tooth holding part). In the optimized plan, it is 25mm in length, 0.7mm in width, and 0.8mm in height. The internal guide rail of the posterior tooth occlusal part is 20-30mm in length (consistent with the length of the connecting rod of the posterior tooth holding part), and has a cross-sectional diameter of 2-3.5mm (≥the cross-sectional diameter of the connecting rod of the posterior tooth holding part). In the optimized plan, the internal guide rail of the posterior tooth occlusal part is 20mm in length and 2mm in cross-sectional diameter. The claw at the end of the posterior tooth occlusal part is a fixing part, with a minimum diameter of 1.6-3mm (consistent with the diameter of the connecting rod of the posterior tooth holding part) and a maximum diameter of 2-3.5mm (consistent with the expansion of the end of the connecting rod of the posterior tooth holding part). In the optimized plan, the minimum diameter is 1.6mm and the maximum diameter is 2mm. The connecting rod of the posterior tooth holding part is 20mm long and has a cross-sectional diameter of 1.6mm. The fixed end of the connecting rod is a frustum (the end of the connecting rod is enlarged, and the claw at the end of the occlusal part is used to clamp the enlargement to prevent it from falling out). The dimensions are an upper diameter of 2mm, a lower diameter of 1.6mm, and a height of 1mm. The holding part can rotate up and down.

[0091] The posterior teeth holding part is provided with a posterior teeth holding part body, a posterior teeth holding part slot and a posterior teeth holding part connecting rod. The two sheet structures of the body are 30mm long, 1.5mm wide, 30mm high and 30mm long, 2mm wide, 20mm high respectively. The reserved gap between the two sheet structures is ≤0.3mm at the narrowest part and 2mm at the widest part. One end of the upper and lower ends is fixed and sealed, and the other end is free (free end) for inserting the tooth piece.

[0092] The dimensions of the slot of the posterior tooth holding part are 30mm long, 0.8mm wide and 0.8mm high. The connecting rod of the posterior tooth holding part is 25mm long and 2.5mm in cross-sectional diameter. The fixed end of the connecting rod is a frustum with the dimensions of 3mm in upper diameter (larger than the cross-sectional diameter), 2.5mm in lower diameter (equal to the cross-sectional diameter) and 1.5mm in height.

[0093] The posterior teeth holding part and the occlusal part are connected by a slot, and the slot method can be a bolt connection method, an embedded connection method, etc. The holding part can rotate up and down. When photographing the upper posterior teeth, the free end of the rotation is upward, and the upper posterior teeth on the left and right sides are respectively connected to the U-shaped grooves of 60° and 300° of the tube fixing ring. When photographing the lower posterior teeth, the free end of the rotation is downward, and the lower posterior teeth on the left and right sides are respectively connected to the U-shaped grooves of 120° and 240° of the tube fixing ring.

[0094] Because the projection frame required to shoot the left and right posterior teeth has to turn around the corners of the patient's mouth, the directions of the corners on both sides are axially symmetrical. This axially symmetrical deformation can be achieved by rotating the film holding part up and down, thereby reducing production costs and the time cost of selecting parts during shooting. The posterior teeth need to be made rotatable.

[0095] The film holding part and the occlusal part of the posterior teeth are split, and are vertically connected to the occlusal part of the posterior teeth through a connecting rod and a slot structure. The film holding part consists of two sheet structures that fit relatively together, with dimensions of 31mm long, 1mm wide, 30mm high and 31mm long, 2.5mm wide, 25mm high respectively. The reserved gap between the two structures is 0.2mm at the narrowest point and 1.5mm at the widest point. One end of the upper and lower ends is fixed and sealed, and the other end is two free sheet structures (free ends) for inserting dental films. The sheet structure is a square block or a rectangular block. The dental film is placed in the gap between the two blocks and clamped to fix it. The parallel projection bracket device is a hard plastic plate, which has no elasticity and yieldability, and has stable retention to prevent morphological deformation and cause projection angle deviation.

[0096] Example 3

[0097] The other contents are the same as those in Example 1, the inner diameter of the ring = 68 mm, the thickness of the ring ≥ 3 mm, and the width of the ring is 10 mm.

[0098] The length of the U-shaped groove is 20mm, the inner diameter of the groove is 10mm, and the height measured from the starting point of the groove concave point is 5.8mm. The built-in slide rail is 10 or 20mm wide, 1 or 3mm long, and 0.5 or 1.5mm high, and the size matches the shape and size of the built-in positioning convex on the U-shaped groove. The extension is a rod-shaped long cylinder with a length of 50 or 100mm and a cross-sectional diameter of 3 or 10mm.

[0099] The anterior occlusal part is a rectangular block with dimensions of 10 or 20 mm in length, 20 or 40 mm in width and 7 or 15 mm in height.

[0100] When taking periapical films, parallel projection technology is used, and a parallel projection bracket that conforms to the principle of parallel projection technology needs to be used. The two-stage parallel projection bracket device described in the present invention includes an X-ray tube fixing ring and a disposable film holding clamp.

[0101] For taking periapical radiographs of maxillary anterior teeth, a disposable film holder is used for the anterior teeth group. The anterior teeth film holder is integrally formed and is divided into an extension part, an occlusal part, and a film holder. The film holder is composed of two pieces, with the dimensions of 16mm long, 1mm wide, 35mm high and 16mm long, 2.5mm wide, 20mm high. The reserved gap between the two pieces is 0.2mm at the narrowest part and 1.5mm at the widest part. When installed, the free end of the film holder is upward, and the extension part is connected to the X-ray tube fixing ring at a 180° U-shaped groove. The sheet structure is a square block or a rectangular block. The tooth piece is placed in the gap between the two pieces and clamped to fix it.

[0102] Before shooting, install the X-ray tube fixing ring onto the tube, then take out the disposable film holder from the sterile sealing bag and install it onto the fixing ring. The installation method for the upper front teeth is as described in the previous paragraph. Put the film into the film holder at the front end of the disposable film holder. After it is firmly in place, put the film holder and the free end of the occlusal part into the patient's mouth on the palate side of the teeth to be photographed, and ask the patient to lightly bite the occlusal part of the disposable film holder with upper and lower teeth. If the patient with a shallow palatal vault cannot bite, a gauze ball can be placed above the occlusal part to increase the height. After the patient's bite is stable, expose and shoot. After the shooting is completed, the patient opens his mouth, the doctor holds the extension of the film holder, moves the tube and removes the film holder and film at the same time, separates the film holder and the X-ray tube fixing ring, removes the film for washing or scanning, and discards the disposable film holder.

[0103] Example 4

[0104] Other contents are the same as those in Example 1, the inner diameter of the ring is 84 mm, the thickness of the ring is ≥ 3 mm, and the width of the ring is 20 mm. The length of the U-shaped groove is 20 mm, the inner diameter of the groove is 6 mm, and the height measured from the starting point of the groove concave point is 5.8 mm. The built-in slide rail is 20 mm wide, 3 mm long, and 1.5 mm high, and its size matches the shape and size of the built-in positioning convex on the U-shaped groove.

[0105] When taking periapical films, parallel projection technology is used, and a parallel projection bracket that conforms to the principle of parallel projection technology is required. The two-stage parallel projection bracket device described in the present invention can be used to complete the parallel projection of the mandibular anterior teeth. The device includes two parts: an X-ray tube fixing ring and a disposable film holding clamp. The specific implementation method is as follows.

[0106] When taking periapical radiographs of the mandibular anterior teeth, use the anterior teeth group of disposable film holders. The anterior teeth group film holder is integrally formed and is divided into an extension part, an occlusal part and a film holder. The film holder is composed of two structures with dimensions of 16 mm in length, 1 mm in width, 35 mm in height and 16 mm in length, 2.5 mm in width, 20 mm in height. The reserved gap between the two structures is 0.2 mm at the narrowest point and 1.5 mm at the widest point. When installed, the free end of the film holder is facing downward, and the extension part is connected to the U-shaped groove at 0° of the X-ray tube fixing ring.

[0107] Before shooting, you need to install the X-ray tube fixing ring on the tube, and then take out the disposable film holder from the sterile sealing bag and install it on the fixing ring. The installation method for the lower front teeth is as described in the previous paragraph. Put the film into the film holding part at the front end of the disposable film holder. After it is firmly in place, put the film holding part and the free end of the occlusal part into the patient's mouth on the lingual side of the teeth to be exposed. Instruct the patient to lightly bite the occlusal part of the disposable film holder with upper and lower teeth. If the patient with a shallow bottom of the mouth cannot bite, a gauze ball can be placed under the occlusal part to increase the height. After the patient's bite is stable, expose and shoot. After the shooting is completed, the patient opens his mouth, the doctor holds the extension of the film holder, moves the tube and removes the film holder and film at the same time, separates the film holder and the X-ray tube fixing ring, removes the film for washing or scanning, and discards the disposable film holder.

[0108] Example 5

[0109] Other contents are as in Example 2. When taking periapical films, parallel projection technology is used, and a parallel projection bracket that conforms to the principle of parallel projection technology is required. The two-stage parallel projection bracket device described in the present invention can be used to complete the parallel projection of the maxillary posterior teeth. The device includes two parts: an X-ray tube fixing ring and a disposable film holding clamp for the posterior teeth group. The specific implementation method is as follows.

[0110] When taking periapical radiographs of maxillary posterior teeth, a disposable film holder is used for the posterior teeth group. The film holder for the posterior teeth group is a split type, with the extension part and the occlusal part integrated. The film holder is connected to the occlusal part through a slot. The film holder is composed of two pieces, with the dimensions of 31mm long, 1mm wide, 30mm high and 31mm long, 2.5mm wide, 25mm high. The reserved gap between the two pieces is 0.2mm at the narrowest point and 1.5mm at the widest point. When installed, the free end of the film holder is facing upward and the lower edge is connected to the occlusal part. When taking pictures of the upper left posterior teeth, the extension part is connected to the U-shaped groove of the X-ray tube fixing ring at 120°; when taking pictures of the upper right posterior teeth, the extension part is connected to the U-shaped groove of the X-ray tube fixing ring at 240°.

[0111] The dimensions of the occlusal area of ​​the posterior teeth are 21 or 30 mm in length, 20 or 30 mm in width, and 6 or 16 mm in height.

[0112] The dimensions of the front end groove of the posterior teeth occlusal part are 21 or 30 mm in length (consistent with the occlusal length), 0.5 or 1 mm in width (consistent with the width of the slot of the posterior teeth holding part), and 0.5 or 1 mm in height (consistent with the height of the slot of the posterior teeth holding part). The internal guide rail of the posterior teeth occlusal part is 20 or 30 mm in length (consistent with the length of the connecting rod of the posterior teeth holding part), and the cross-sectional diameter is 2 or 3.5 mm (≥ the cross-sectional diameter of the connecting rod of the posterior teeth holding part). The claw at the end of the posterior teeth occlusal part is a fixing part, with a minimum diameter of 1.6 or 3 mm (consistent with the diameter of the connecting rod of the posterior teeth holding part) and a maximum diameter of 2 or 3.5 mm (consistent with the expansion of the end of the connecting rod of the posterior teeth holding part).

[0113] The posterior teeth holding part is provided with a posterior teeth holding part body, a posterior teeth holding part slot and a posterior teeth holding part connecting rod. The two sheet structures of the body are respectively 25 or 35 mm long, 1 or 2 mm wide, 20 or 35 mm high and 2 or 35 mm long, 1 or 2.5 mm wide, 15 or 30 mm high. The reserved gap between the two sheet structures is ≤0.3 mm at the narrowest point and 1 or 2.5 mm at the widest point. One end of the upper and lower ends is fixed and sealed, and the other end is free (free end) for inserting the tooth piece.

[0114] The dimensions of the slot of the posterior tooth holding part are 25 or 35 mm long, 0.5 or 1 mm wide, and 0.5 or 1 mm high. The connecting rod of the posterior tooth holding part is 20 or 30 mm long, with a cross-sectional diameter of 1.6 or 3 mm. The fixed end of the connecting rod is a frustum with an upper diameter of 2 or 3.5 mm (larger than the cross-sectional diameter), a lower diameter of 1.6 or 3 mm (equal to the cross-sectional diameter), and a height of 1 or 2 mm.

[0115] Before shooting, you need to install the X-ray tube fixing ring on the tube, and then take out the disposable film holder from the sterile sealing bag and install it on the fixing ring. The installation method for the upper posterior teeth is as described in the previous paragraph. Put the film into the film holding part at the front end of the disposable film holder. After it is firmly in place, put the film holding part and the free end of the occlusal part into the patient's mouth on the palate side of the teeth to be exposed, and ask the patient to lightly bite the occlusal part of the disposable film holder with upper and lower teeth. If the patient with a shallow palatal vault cannot bite, a gauze ball can be placed above the occlusal part to increase the height. After the patient's bite is stable, expose and shoot. After the shooting is completed, the patient opens his mouth, the doctor holds the extension of the film holder, moves the tube and removes the film holder and film at the same time, separates the film holder and the X-ray tube fixing ring, removes the film for washing or scanning, and discards the disposable film holder.

[0116] Example 6

[0117] Other contents are as described in Example 2. When taking periapical films, parallel projection technology is used, and a parallel projection bracket that conforms to the principle of parallel projection technology is required. The two-stage parallel projection bracket device described in the present invention can be used to complete the parallel projection of the mandibular posterior teeth. The device includes two parts: an X-ray tube fixing ring and a disposable film holding clamp for the posterior teeth group. The specific implementation method is as follows.

[0118] When taking periapical radiographs of mandibular posterior teeth, a disposable film holder is used for the posterior teeth group. The film holder for the posterior teeth group is a split type, with the extension part and the occlusal part integrated. The film holder is connected to the occlusal part through a slot. The film holder is composed of two pieces, with the dimensions of 31mm long, 1mm wide, 30mm high and 31mm long, 2.5mm wide, 25mm high. The reserved gap between the two pieces is 0.2mm at the narrowest point and 1.5mm at the widest point. When installed, the free end of the film holder is facing downward and the upper edge is connected to the occlusal part. When taking pictures of the lower left posterior teeth, the extension part is connected to the U-shaped groove at 60° with the X-ray tube fixing ring; when taking pictures of the lower right posterior teeth, the extension part is connected to the U-shaped groove at 300° with the X-ray tube fixing ring.

[0119] Before shooting, you need to install the X-ray tube fixing ring on the tube, and then take out the disposable film holder from the sterile sealing bag and install it on the fixing ring. The installation method for the lower posterior teeth is as described in the previous paragraph. Put the film into the film holding part at the front end of the disposable film holder. After it is firmly in place, put the film holding part and the free end of the occlusal part into the patient's mouth on the lingual side of the teeth to be photographed, and ask the patient to lightly bite the occlusal part of the disposable film holder with upper and lower teeth. If the patient with a shallow bottom of the mouth cannot bite, a gauze ball can be placed under the occlusal part to increase the height. After the patient's bite is stable, expose and shoot. After the shooting is completed, the patient opens his mouth, the doctor holds the extension of the film holder, moves the tube and removes the film holder and film at the same time, separates the film holder and the X-ray tube fixing ring, removes the film for washing or scanning, and discards the disposable film holder.

[0120] When the patient needs to use parallel projection technology to shoot the root apex, choose a two-stage parallel projection stand. First, the X-ray tube fixing ring can be fixed to the outer edge of the tube for a long time. Select a disposable film holder for the anterior or posterior teeth group to place the film and the film holder. According to the specific tooth position for shooting, connect the film holder to the corresponding U-shaped groove of the fixing ring to complete the assembly. Ask the patient to open his mouth wide, adjust the position and angle of the tube, put the film holder and the occlusal part of the film holder into the corresponding tooth position in the patient's mouth, ask the patient to bite the occlusal part with the upper and lower teeth, keep still, and complete the exposure.

[0121] Test 1

[0122] As in the operating steps of Example 3, the parallel projection technology is used to take the periapical film of the maxillary anterior teeth after implant surgery, and the two-stage parallel projection bracket is used for the anterior teeth group. After the shooting is completed, the angle bisector technique is used to take the periapical film of the anterior teeth again, and the patient presses the film with his fingers to fix it. The two groups of images are compared to observe the elongation or compression of the anterior teeth and the overlap of the implant threads. The results show that the periapical images obtained using the two-end parallel projection bracket have no deformation or distortion of the anterior teeth, there is no overlap of the implant threads, and the bone integration is easy to observe; the periapical images obtained by the angle bisector method are partially elongated or compressed, and the implant threads in some pictures overlap, and the bone growth between the threads cannot be judged, affecting the diagnosis. The details are shown in Table 1 below:

[0123] Table 1. Comparison of periapical radiographs taken using a two-stage parallel projection support device and finger pressure

[0124]

[0125] Test 2

[0126] As in the operating steps of Example 6, the parallel projection technology is used to take the periapical film of the maxillary posterior teeth of patients with interproximal caries, and the posterior teeth group using a two-stage parallel projection bracket. After the shooting is completed, the angle bisector technique is used to take the periapical film of the posterior teeth in the same tooth position again, and the patient presses the film with his fingers to fix it. The two groups of images are compared to observe the elongation or compression of the posterior teeth, the overlap of the interproximal surfaces of the posterior teeth, and the display of interproximal caries. The results show that the periapical film images obtained using the two-end parallel projection bracket have no deformation or distortion of the posterior teeth, no overlap of adjacent teeth, and the location and range of interproximal caries are easy to observe; the periapical film images obtained by the angle bisector method are partially elongated or compressed, and the adjacent surfaces of some pictures overlap, affecting the diagnosis of interproximal caries. The details are shown in Table 1 below:

[0127] Table 1. Comparison of periapical radiographs taken using a two-stage parallel projection support device and finger pressure

[0128]

[0129]

[0130] One section of the support device in the present invention is an X-ray tube fixing ring that does not contact the human body and is fixed to the outer edge of the tube, and does not need to be replaced or disinfected for each person; the other section is a disposable film holding clamp that contacts the oral cavity, is placed on the tooth to be irradiated, and is fixed by the patient's occlusion, and the extension part is connected to the U-shaped groove of the X-ray tube fixing ring through a built-in slide rail. The film holding clamp is divided into an anterior teeth group and a posterior teeth group. The anterior teeth group is integrally formed, and the film holding part of the posterior teeth group is connected to the occlusal part and can be rotatably separated, which can meet the requirements of shooting of the posterior teeth in four quadrants.

[0131] This invention is supported by the Sichuan Science and Technology Program.

[0132] The present invention realizes that when using the parallel projection technology to shoot periapical films, a two-stage device is used to assemble an X-ray tube fixing ring and a disposable film holder, and the obtained image is clear and free of deformation, while reducing the cost of consumables and meeting the principle of hospital infection control. The method is convenient, easy to learn and use, reduces costs, helps to promote the parallel projection technology, and is conducive to improving the image quality of periapical films in oral medical institutions at all levels.

[0133] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A two-stage parallel projection support device for taking periapical radiographs using parallel projection technology, characterized in that: It comprises a tube fixing ring and a disposable film holding clip, wherein the fixing ring is provided with a ring body and N U-shaped grooves, N≥1; the U-shaped groove is provided on the outer surface of the ring body; the disposable film holding clip comprises an extension part, a connecting rod, a bite part and a film holding part, wherein the film holding part is connected with one end of the bite part, and the two ends of the connecting rod are respectively vertically connected with the extension part and the other end of the bite part, and the extension part is parallel to the bite part and extends in opposite directions; one end of the connecting rod is vertically connected with the extension part, and the other end of the extension part extends into the U-shaped groove, so that the fixing ring and the disposable film holding clip are fixedly connected into one body; The tube fixing ring is an X-ray tube fixing ring, which is in a circular shape, with an inner diameter of 68-84 mm, a thickness of 3 mm or more, and a width of 10-20 mm; The extension part is longitudinally provided with a built-in slide rail, and the inner surface of the U-shaped groove is provided with a built-in positioning protrusion. When in use, the built-in positioning protrusion is embedded in the built-in slide rail and slides relative to the built-in slide rail.

2. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The U-shaped groove is provided with a groove concave point and two L-shaped arms, the groove concave point is arranged at the center point of the U-shaped bottom end, and the two L-shaped arms are symmetrically arranged with the groove concave point to form a U shape, and the U-shaped groove is fixedly connected to the fixing ring at the groove concave point.

3. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The built-in positioning protrusion is in the shape of a triangular prism, and its size matches the built-in slide rail of the extension part; the built-in positioning protrusion is located at the 0° and 90° positions relative to the concave point of the U-shaped groove.

4. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The N=8, that is, 8 U-shaped grooves are provided on the outer edge.

5. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The extension part is a rod-shaped long cylinder with a length of 50-100 mm and a cross-sectional diameter of 3-10 mm.

6. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The connection between the bite portion and the sheet holding portion, the extension portion and the connecting rod, or the connecting rod and the bite portion is a movable connection or an integrated fixed connection.

7. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 1, characterized in that: The connection between the sheet holding part and the bite part, and when the bite part and the connecting rod are in a movable connection mode, the sheet holding part is provided with a posterior teeth sheet holding part body, a posterior teeth sheet holding part slot and a posterior teeth sheet holding part connecting rod, the posterior teeth sheet holding part slot is transversely arranged on an outer surface of the sheet-like structure, one end of the posterior teeth sheet holding part connecting rod is connected to the sheet-like structure; the end of the posterior teeth sheet holding part connecting rod is provided with an expansion at the end of the posterior teeth sheet holding part connecting rod; the bite part is provided with a front end groove of the posterior teeth bite part, an internal guide rail of the posterior teeth bite part and a claw type at the end of the posterior teeth bite part, and the front end groove of the posterior teeth bite part It is arranged at the front end of the occlusal part, and the internal guide rail of the posterior teeth occlusal part passes through the center of the interior of the occlusal part; the claw type at the end of the posterior teeth occlusal part is arranged inside the rear end of the occlusal part, and is connected to the internal guide rail of the posterior teeth occlusal part; the shape and size of the groove at the front end of the posterior teeth occlusal part are matched with the shape and size of the slot of the posterior teeth holding part, and the claw type at the end of the posterior teeth occlusal part is matched with the swollen shape at the end of the connecting rod of the posterior teeth holding part; when connected, the connecting rod of the posterior teeth holding part is inserted into the internal guide rail of the posterior teeth occlusal part and is fixed with the claw type at the end of the posterior teeth occlusal part, so that the holding part at the other end can be rotated.

8. The two-stage parallel projection support device for taking periapical radiographs using parallel projection technology according to claim 7, characterized in that: The dimensions of the front end groove of the posterior tooth occlusal part are 30-31mm in length, 0.7mm in width, and 0.8mm in height. The internal guide rail of the posterior tooth occlusal part is 20mm in length and 2mm in cross-sectional diameter. The claw at the end of the posterior tooth occlusal part is a fixing part with a minimum diameter of 1.6mm and a maximum diameter of 2mm.

Images