Oral cavity insertion tool

Abstract

To provide an oral cavity insertion tool which enables medical equipment, such as a sonde, to be readily inserted into an oral cavity of a rodentia animal in a procedure of an oral administration of an administration substance into the rodentia animal, and can prevent the medical equipment, such as a sonde, from being damaged.SOLUTION: A cylindrical oral cavity insertion tool 10 is to be inserted from a mouth 21 of a rodentia animal 20, and has a lumen 10A extending in a longitudinal axis direction, a bend part 15, a first end 11 in a distal side in the longitudinal axis direction, and a second end 12 in a proximal side. The first end 11 and the second end 12 each has an opening communicating with the lumen 10A. The shape of the opening 12A of the second end 12 has a long axis 12L and a short axis 12S. The short axis 12S extends in a range of -30° to +30° with respect to a plane A including a central axis of the bend part 15.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an oral cavity insert that is inserted through the mouth of a rodent. [Background technology]

[0002] When administering drugs or feed orally to laboratory animals such as mice and rats, a thin, tubular medical device called a probe is used. The distal end of the probe is inserted into the oral cavity of the laboratory animal, and the substance to be administered is injected from the proximal end of the probe, allowing the substance to be forcibly administered from the esophagus to the stomach or respiratory tract of the laboratory animal.

[0003] For example, Patent Document 1 discloses a stainless steel sonde. Metallic sondes are inferior in flexibility, so resin sondes have also been devised. For example, Patent Document 2 discloses a sonde that includes a tip portion formed of a metallic conduit, a base portion formed of a metallic conduit, and a flexible intermediate tube that connects the tip portion and the base portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 1-104112 [Patent Document 2] Japanese Utility Model Application Publication No. 4-37417 Summary of the Invention [Problem to be solved by the invention]

[0005] Rodents such as mice and rats have two incisors on both the upper and lower jaws that continue to grow. When a probe is inserted into the oral cavity of a rodent, the incisors can damage the probe. In this regard, a metal probe as disclosed in Patent Document 1 has the advantage of being less susceptible to damage, but is inferior in terms of flexibility and cost. In addition, the probe disclosed in Patent Document 2 uses both metal and synthetic resin to maintain flexibility while preventing damage caused by the teeth of the test animal, but the structure is complex and expensive, making it unsuitable as a disposable probe.

[0006] Furthermore, when inserting the probe into the oral cavity of a rodent, the distal end of the probe must be pushed further out of the oral cavity of the rodent while avoiding the rodent's teeth, which requires skill on the part of the user.

[0007] In view of the above circumstances, an object of the present invention is to provide an oral cavity insertion device that allows a medical instrument such as a probe to be easily inserted into the oral cavity of a rodent when orally administering a substance to the rodent, and that prevents damage to the medical instrument such as a probe. [Means for solving the problem]

[0008] The oral cavity insertion device according to the embodiment of the present invention that can solve the above problems is as follows. [1] A cylindrical oral cavity insertion device to be inserted into the mouth of a rodent, the oral cavity insertion device having an inner cavity extending in a longitudinal direction, a curved portion, and a first end on a distal side and a second end on a proximal side in the longitudinal direction, the first end and the second end each having an opening communicating with the inner cavity, the shape of the opening at the second end having a major axis and a minor axis, and the minor axis extending in a range of -30° to +30° with respect to a plane A including a central axis of the curved portion.

[0009] Since the oral cavity insertion tool has a curved portion, the oral cavity insertion tool can be easily inserted by inserting the curved portion from the mouth of the rodent toward the back along the wall of the body cavity. At this time, since the curved portion is aligned along the wall of the body cavity of the rodent, the short axis of the opening at the proximal second end extends substantially parallel to the plane A including the central axis of the curved portion, so that the short axis can extend in the opening and closing direction of the mouth of the rodent. This can prevent the mouth of the rodent from closing while reducing stress caused by opening the mouth of the rodent too wide. Therefore, it is possible to prevent the medical tool from being bitten and damaged by inserting a medical tool such as a probe into the cavity of the oral cavity insertion tool. In addition, since the opening at the proximal second end has a long axis, the proximal end of the oral cavity opening tool can be stably positioned in the mouth of the rodent. Furthermore, because the oral cavity insertion device prevents the rodent from closing its mouth, there is no need to avoid the teeth when inserting a medical instrument such as a probe, and the medical instrument can be inserted easily regardless of the user's skill.

[0010] The oral cavity insertion device according to the embodiment of the present invention is preferably any one of the following [2] to [9]. [2] The oral cavity insertion device according to [1], wherein the major axis extends in a range of −30° to +30° with respect to a perpendicular line to the plane A. [3] The oral cavity insertion device according to [1] or [2], wherein the ratio of the major axis to the minor axis (major axis / minor axis) is 1.1 or more and 3.5 or less. [4] The oral cavity insertion device according to any one of [1] to [3], wherein an area of ​​the opening at the second end is larger than an area of ​​the opening at the first end. [5] The oral cavity insertion device according to any one of [1] to [4], wherein an outer diameter of the oral cavity insertion device at the first end is smaller than an outer diameter of the oral cavity insertion device at the second end. [6] The oral cavity insertion device according to any one of [1] to [5], wherein an outer diameter of the oral cavity insertion device at a midpoint in the longitudinal axis direction is smaller than an outer diameter of the oral cavity insertion device at the second end. [7] The oral cavity insertion device according to any one of [1] to [6], further comprising an expanding portion, the inner diameter of which expands from the first end side to the second end side, on the second end side of a midpoint in the longitudinal axis direction. [8] The oral cavity insertion device according to [7], wherein the area of ​​the inner cavity of the expanded diameter portion is maximized at the second end. [9] The oral cavity insertion device according to [7], wherein the area of ​​the inner cavity of the expanded diameter portion is greatest on the first end side relative to the second end in the longitudinal axis direction. Effect of the Invention

[0011] According to the oral cavity insertion device, when a substance to be administered is orally to a rodent, a medical instrument such as a probe can be easily inserted into the oral cavity of the rodent, and damage to the medical instrument can be prevented. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of an oral cavity insertion instrument according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a proximal end view of the oral cavity insertion device shown in FIG. 1. [Diagram 3] 3 is another example of an end view of FIG. 2. [Figure 4] FIG. 1 is a diagram illustrating a state in which an oral cavity insertion device according to an embodiment of the present invention is inserted from the mouth of a rodent. [Diagram 5] 2 is a cross-sectional view taken along a longitudinal axis of the oral cavity insertion instrument shown in FIG. 1. [Figure 6] 6 is another example of the cross-sectional view shown in FIG. 5. [Figure 7] FIG. 13 is a proximal end view of an oral cavity insertion device according to another embodiment of the present invention. [Figure 8] 8 is another example of the end view shown in FIG. 7. [Figure 9] FIG. 11 is a longitudinal axial cross-sectional view of an oral cavity insertion device according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described below based on the embodiments, but the present invention is not limited to the following embodiments, and can be modified as appropriate within the scope of the above and below, and all of these are included in the technical scope of the present invention. In addition, hatching and component symbols may be omitted in each drawing for convenience, but in such cases, the specification and other drawings should be referred to. Furthermore, the dimensions of various components in the drawings may differ from the actual dimensions, since priority is given to helping understand the features of the present invention.

[0014] An oral cavity insertion device according to an embodiment of the present invention will be described with reference to Figs. 1 to 9. Fig. 1 is a perspective view of an oral cavity insertion device according to an embodiment of the present invention. Fig. 2 is an end view of the proximal side of the oral cavity insertion device shown in Fig. 1, i.e., an end view of the second end, and Fig. 3 is another example of the end view of Fig. 2. Fig. 4 is a view showing a state in which an oral cavity insertion device according to an embodiment of the present invention is inserted from the mouth of a rodent. Fig. 4 shows a probe as an example of a medical instrument that can be inserted into the cavity of the oral cavity insertion device. Fig. 5 is a cross-sectional view in the longitudinal direction including the central axis of the oral cavity insertion device shown in Fig. 1, and Fig. 6 is another example of the cross-sectional view shown in Fig. 5. Fig. 7 is an end view of the proximal side of an oral cavity insertion device according to another embodiment of the present invention, i.e., an end view of the second end, and Fig. 8 is another example of the end view shown in Fig. 7. Fig. 9 is a cross-sectional view in the longitudinal direction including the central axis of an oral cavity insertion device according to yet another embodiment of the present invention.

[0015] The distal side of the oral cavity insertion device 10 is the side that is first inserted into the mouth of a rodent in the longitudinal axis direction x of the oral cavity insertion device 10 and is the side that is ultimately disposed at the back of the rodent's body. The proximal side of the oral cavity insertion device 10 is the side opposite the distal side and is the side that is located closer to the user's hand.

[0016] As shown in FIGS. 1 to 4 , oral cavity insertion device 10 is a cylindrical oral cavity insertion device 10 to be inserted from mouth 21 of rodent 20, and has inner cavity 10A extending in longitudinal axis direction x, curved portion 15, and first end 11 on the distal side and second end 12 on the proximal side in longitudinal axis direction x. First end 11 and second end 12 have openings 11A and 12A communicating with inner cavity 10A, respectively. Opening 12A of second end 12 has a shape with long axis 12L and short axis 12S, and short axis 12S extends in a range R of −30° to +30° with respect to plane A including central axis X of curved portion 15.

[0017] Because the oral cavity insertion device 10 has a curved portion 15, when the oral cavity insertion device 10 is inserted into the mouth 21 of the rodent 20 from the first end 11 side, the curved portion 15 easily follows the wall of the body cavity of the rodent 20, such as the esophagus or airway, and the curved portion 15 can be easily inserted from the mouth 21 of the rodent 20 through the oral cavity 23 to the back.

[0018] 1 to 3, when the curved portion 15 is inserted from the mouth 21 of the rodent 20 toward the back, the short axis 12S of the opening 12A of the proximal second end 12 extends in a range R of -30° to +30°, i.e., approximately parallel, to a plane A including the central axis X of the curved portion 15. The angle at which the short axis 12S extends to the plane A including the central axis X of the curved portion 15 can be -25° to +25°, -20° to +20°, -10° to +10°, -5° to +5°, -3° to +3°, etc., and may be 0°, i.e., the short axis 12S extends parallel to the plane A as shown in FIG. 2. 4, the minor axis 12S of the opening 12A of the second end 12 can extend in the opening and closing direction of the mouth 21, thereby reducing stress caused by opening the mouth 21 of the rodent 20 too wide while making it difficult to close the mouth 21 and preventing the teeth 22 (upper teeth 22a and lower teeth 22b) from interlocking. Therefore, by inserting a medical instrument such as a probe 30 into the cavity 10A of the oral cavity insertion instrument 10 in the direction shown by the arrow, the medical instrument can be prevented from being bitten and damaged.

[0019] Furthermore, because opening 12A of proximal second end 12 has long axis 12L, inner cavity 10A of oral cavity insertion device 10 can be secured widely in the direction of extension of long axis 12L, so that a medical instrument such as probe 30 can be easily inserted regardless of the user's skill or dominant hand.

[0020] Here, the short axis 12S extending at -30° with respect to the plane A means that the short axis 12S is inclined 30° counterclockwise with respect to the plane A when the opening 12A is viewed from the proximal side, and the short axis 12S extending at +30° with respect to the plane A means that the short axis 12S is inclined 30° clockwise with respect to the plane A when the opening 12A is viewed from the proximal side. In other words, the angle formed by the extension direction of the short axis 12S with respect to the extension direction of the plane A is in the range of -30° or more and +30° or less. As shown in Figs. 2 and 3, the short axis 12S of the opening 12A of the second end 12 of the oral cavity insertion instrument 10 preferably extends within a range R of -30° to +30° with respect to the plane A.

[0021] In this specification, the probe 30 is described as a representative example of a medical instrument to be inserted into the cavity 10A of the oral cavity insertion instrument 10. However, the medical instrument to be inserted into the cavity 10A of the oral cavity insertion instrument 10 may be an endoscope or a catheter other than the probe 30.

[0022] The rodent 20 is an animal belonging to the order Rodentia of the class Mammalia. The rodent 20 is relatively small and has a pair of upper and lower teeth 22 (incisors). The rodent 20 includes, for example, mice, rats, guinea pigs, guinea pigs, hamsters, beavers, squirrels, mole rats, porcupines, capybaras, etc. Among them, mice, rats, and guinea pigs are suitable as experimental animals.

[0023] When orally administering drugs or feed to laboratory animals as described above, a thin tubular instrument such as the probe 30 is used. The probe 30 may be made of resin or metal, or may be composed of resin and metal, but a resin probe 30 is preferably used as a disposable probe 30 for oral administration to laboratory animals because it is flexible and can be manufactured inexpensively. Even if the probe 30 is made of resin, the use of the oral cavity insertion tool 10 can prevent the probe 30 from being damaged by the teeth 22.

[0024] 5 and 6, the minor axis 12S preferably extends in the range of -30° to +30° with respect to a plane B perpendicular to the central axis X at the second end 12. For example, as shown in Fig. 5, the minor axis 12S may extend at 0° with respect to the plane B, that is, parallel to the plane B. Alternatively, as shown in Fig. 6, for example, the minor axis 12S may extend at an angle with respect to the plane B, and the angle can be -30° to +30°, -20° to +20°, -10° to +10°, -5° to +5°, -3° to +3°, etc.

[0025] As shown in FIG. 6, when the short axis 12S extends at an angle with respect to the plane B, it is preferable that the second end 12 located most proximal is located on the opposite side to the bending direction of the curved portion 15. That is, it is preferable that one end of the long axis 12L located on the outer side of the curved portion 15 is located closer to the proximal side in the longitudinal axis direction x than the other end located on the inner side of the curved portion 15. This allows the side of the second end 12 that abuts against the upper teeth 22a to be located closer to the proximal side and the side that abuts against the lower teeth 22b to be located more distally when the curved portion 15 is inserted from the mouth 21 of the rodent 20 toward the back. Since the teeth 22 of the rodent 20 used as the experimental animal are such that the upper teeth 22a are more outward than the lower teeth 22b, the above configuration allows the oral cavity insertion device 10 to more easily protect the medical instrument such as the probe 30 inserted into the cavity 10A from the teeth 22 of the rodent 20.

[0026] The oral cavity insertion instrument 10 is cylindrical and has an inner cavity 10A. The oral cavity insertion instrument 10 may have any cylindrical shape as long as the first end 11 side can be inserted into the oral cavity 23 of the rodent 20. The length in the longitudinal axis direction x of the oral cavity insertion instrument 10 can be, for example, 10 mm or more, 15 mm or more, 20 mm or more, 30 mm or more, 50 mm or more, and 200 mm or less, 150 mm or less, 100 mm or less, etc. The thickness of the cylindrical shape of the oral cavity insertion instrument 10 can be, for example, 0.5 mm or more, 1 mm or more, 1.5 mm or more, 2 mm or more, and 10 mm or less, 8 mm or less, 5 mm or less, 3 mm or less, etc.

[0027] The shape of opening 12A at second end 12 is not particularly limited as long as it has a major axis 12L and a minor axis 12S, but is preferably a circle such as an ellipse, a polygon such as a rectangle, or a rounded polygon such as a rounded rectangle, and is more preferably a circle such as an ellipse.

[0028] The major axis 12L of the shape of the opening 12A is the longest line segment among the line segments that connect two points on the edge of the opening 12A and pass through the centroid of the shape of the opening 12A, and the minor axis 12S of the shape of the opening 12A is the shortest line segment among the line segments that connect two points on the edge of the opening 12A and pass through the centroid of the shape of the opening 12A. When the shape of the opening 12A is an ellipse as shown in Figures 2 and 3, the major axis 12L is a line segment that passes through two foci of the line segment connecting two points on the ellipse, and the minor axis 12S is a line segment that passes through the midpoint of the major axis 12L and is perpendicular to the major axis 12L.

[0029] 7 and 8, and a rectangular shape (not shown). When the shape of opening 12A is a rounded rectangle or a rectangle, long axis 12L is a line segment that passes through the centroid of the rounded rectangle or rectangle and is parallel to the long side, among lines connecting two points on the rounded rectangle or rectangle, and short axis 12S is a line segment that passes through the centroid of the rounded rectangle or rectangle and is parallel to the short side, among lines connecting two points on the rounded rectangle or rectangle.

[0030] 2, 3, 7, and 8, it is preferable that the long axis 12L and the short axis 12S of the shape of the opening 12A intersect perpendicularly. This allows the oral cavity insertion device 10 to be stably placed in the mouth 21 of the rodent 20. In this way, the angle at which the long axis 12L and the short axis 12S intersect is not limited to 90°, and the smaller angle may be 90° or less and may be 85° or more, 80° or more, 75° or more, 70° or more, or 60° or more.

[0031] The central axis X of the curved portion 15 preferably exists on the same plane. That is, the central axis X of the curved portion 15 preferably exists on the plane A, and the curved portion 15 is preferably not twisted. Here, the curved portion 15 preferably has a proximal end and a distal end, and the proximal end of the curved portion 15 is a position where the extension direction of the central axis X, which is a constant direction on the proximal side of the proximal end, starts to curve, and the distal end of the curved portion 15 is a position where the extension direction of the central axis X, which was curved in the curved portion 15, becomes a constant direction. The curved portion 15 is preferably configured so that the central axis X exists on the plane A in at least a part from the proximal end to the distal end, and more preferably configured so that the central axis X exists on the plane A throughout the entire portion from the proximal end to the distal end.

[0032] 4 to 6, the degree of curvature of the curved portion 15 can be defined as an angle α between a tangent to the central axis X at the proximal end of the curved portion 15 and a tangent to the central axis X at the distal end of the curved portion 15 in the inward direction of the curved portion 15. The angle α is not particularly limited as long as the curved portion 15 can be inserted deep into the oral cavity 23 of the rodent 20, but can be, for example, 90° or more, 100° or more, 120° or more, and 175° or less, 170° or less, 160° or less, 150° or less, etc.

[0033] 1, 5, and 6, the curved portion 15 is preferably located distal to the midpoint 13 of the oral cavity insertion device 10. This makes it easy to insert the curved portion 15 deep into the oral cavity 23 of the rodent 20 when the oral cavity insertion device 10 is inserted into the mouth 21 of the rodent 20 from the first end 11 on the distal side.

[0034] The cross-sectional shape of the oral cavity insertion instrument 10 proximal to the second end 12 is not particularly limited, but is preferably circular or elliptical. This makes it difficult for the oral cavity insertion instrument 10 to get caught on the wall of a body cavity such as the oral cavity 23 of the rodent 20. The cross-sectional shape of the inner cavity 10A may be the same or different along the longitudinal axis direction x.

[0035] The shape of opening 11A at first end 11 is not particularly limited, but is preferably circular or elliptical. When opening 11A is circular, opening 11A is preferably formed perpendicular to the longitudinal axis direction x. Here, perpendicular includes opening 11A extending within a range of -5° to +5° with respect to a plane perpendicular to the longitudinal axis direction x.

[0036] 4, the shape of the opening 11A at the first end 11 is an ellipse formed by cutting a tube obliquely, and the shape of the opening 11A at the first end 11 may have a major axis and a minor axis. The major axis of the shape of the opening 11A at the first end 11 preferably extends in a range of -30° to +30° with respect to a plane A including the central axis X of the curved portion 15, and the range in which the major axis extends may be -25° to +25°, -20° to +20°, -10° to +10°, -5° to +5°, -3° to +3°, etc., and may even be 0°. In other words, the major axis of the shape of the opening 11A at the first end 11 preferably extends approximately parallel to the plane A.

[0037] When the shape of the opening 11A at the first end 11 has a long axis and the long axis extends substantially parallel to the plane A, it is preferable that, as shown in FIG. 4, one end of the long axis located on the inner side of the curved portion 15 is located distal to the other end located on the outer side of the curved portion 15 in the longitudinal axis direction x. This makes it easier for the first end 11 to follow the wall of the body cavity of the rodent 20 when the first end 11 is advanced from the mouth 21 of the rodent 20 to the back of the oral cavity 23. Alternatively, depending on the site to which the first end 11 is inserted, one end of the long axis located on the inner side of the curved portion 15 may be located proximal to the longitudinal axis direction x than the other end located on the outer side of the curved portion 15. Alternatively, the opening 11A at the first end 11 may be formed by cutting the tube obliquely so that both ends of the long axis face in any direction depending on the site to which the first end 11 is inserted and the ease of insertion. When opening 11A at first end 11 is formed by cutting a tube obliquely, the cut surface preferably extends in the range of -45° to +45° with respect to a plane perpendicular to the longitudinal axis direction x. This range is more preferably -30° to +30°, and even more preferably -15° to +15°. This prevents first end 11 from becoming too sharp and from injuring the wall of the body cavity, such as oral cavity 23, of rodent 20.

[0038] 1, 5, 6, and 9, the opening 11A of the first end 11 may be perpendicular to the central axis X. That is, a point on the edge of the opening 11A of the first end 11 may be located at the same position in the longitudinal axis direction x.

[0039] 2 and 3, the long axis 12L preferably extends in the range of -30° to +30° with respect to the perpendicular line P to the plane A. With this configuration, when the curved portion 15 of the oral cavity insertion device 10 is inserted deep into the oral cavity 23 of the rodent 20, the long axis 12L can be made to extend in the lateral direction of the mouth 21 of the rodent 20. With this configuration, it becomes easier to stably place the oral cavity insertion device 10 in the mouth 21 of the rodent 20.

[0040] 5 and 6, the long axis 12L preferably extends parallel to a plane B perpendicular to the central axis X at the second end 12. This allows the second end 12 of the oral cavity insertion device 10 to be disposed at the same position on the left and right sides of the mouth 21 of the rodent 20. Alternatively, the long axis 12L may extend at an angle to the plane B, but the angle is preferably small. The angle can be, for example, -30° to +30°, -20° to +20°, -10° to +10°, -5° to +5°, -3° to +3°, or the like.

[0041] The ratio of the major axis 12L to the minor axis 12S (major axis 12L / minor axis 12S) is preferably 1.1 or more, more preferably 1.2 or more, even more preferably 1.3 or more, particularly preferably 1.5 or more, and is preferably 3.5 or less, more preferably 3.3 or less, even more preferably 3.0 or less, and particularly preferably 2.5 or less. If the ratio of the major axis 12L to the minor axis 12S (major axis 12L / minor axis 12S) is within the above range, the length of the minor axis 12S extending in the opening and closing direction of the mouth 21 of the rodent 20 can be set to a predetermined value or less, so that it becomes easier to prevent the mouth 21 of the rodent 20 from being opened too widely. In addition, since the length of the major axis 12L can be set to a predetermined value or more, it becomes easier to insert the medical instrument of the probe 30 inserted into the inner cavity 10A of the oral cavity insertion device 10 from any direction.

[0042] Furthermore, if the ratio of major axis 12L to minor axis 12S is within the above range, oral cavity insertion device 10 can be used for rodents 20 having mouths 21 of different sizes, such as mice and rats.

[0043] As shown in FIG. 1, the area of ​​the opening 12A of the second end 12 is preferably larger than the area of ​​the opening 11A of the first end 11. After the oral cavity insertion device 10 is inserted into the mouth 21 of the rodent 20 from the first end 11 on the distal side, a medical instrument such as a probe 30 is inserted into the cavity 10A from the opening 12A of the second end 12 on the proximal side, and the large area of ​​the opening 12A of the second end 12 makes it easier to insert the medical instrument. In particular, it becomes easier to insert the medical instrument from any direction, making it easier to perform the procedure regardless of the skill or dominant hand of the user. In addition, since the area of ​​the opening 11A of the first end 11 is relatively small, it becomes easier to insert the first end 11 deep into the oral cavity 23 of the rodent 20.

[0044] The area of ​​opening 12A of second end 12 can be 1.5 times or more, 2 times or more, 3 times or more, 5 times or more, and 30 times or less, 20 times or less, 10 times or less, etc., the area of ​​opening 11A of first end 11.

[0045] Specifically, the length of the major axis of the opening 11A of the first end 11 can be 1 mm or more, 2 mm or more, 3 mm or more, and 10 mm or less, 8 mm or less, 5 mm or less, etc. The major axis of the opening 11A of the first end 11 is the diameter when the shape of the opening 11A is a circle, the major axis when the shape of the opening 11A is an ellipse, and the length of the long side when the shape of the opening 11A is a rectangle or a rectangle with rounded corners, and is the same as the major axis 12L of the shape of the opening 12A of the second end 12 described above. An oral cavity insertion device 10 in which the major axis of the opening 11A of the first end 11 is short can be easily used for a relatively small rodent 20 such as a mouse, and an oral cavity insertion device 10 in which the major axis of the opening 11A of the first end 11 is long can be easily used for a relatively large rodent 20 such as a rat.

[0046] The length of major axis 12L of opening 12A of second end 12 may be set so that the ratio of the area of ​​opening 12A of second end 12 to the area of ​​opening 11A of first end 11 is within the above range. For example, the length of major axis 12L may be 5 mm or more, 8 mm or more, and 30 mm or less, 20 mm or less, 15 mm or less, 12 mm or less, 10 mm or less, etc. when oral cavity insertion device 10 is used for a relatively small rodent 20 such as a mouse, and may be 8 mm or more, 10 mm or more, 15 mm or more, and 70 mm or less, 50 mm or less, 40 mm or less, 35 mm or less, 30 mm or less, 20 mm or less, etc. when oral cavity insertion device 10 is used for a relatively large rodent 20 such as a rat.

[0047] 1, 5, 6, and 9, the outer shape of oral cavity insertion device 10 at first end 11 is preferably smaller than the outer diameter of oral cavity insertion device 10 at second end 12. Since first end 11 of oral cavity insertion device 10 is the portion that is inserted from mouth 21 through oral cavity 23 of rodent 20 to the back, the smaller outer diameter at first end 11 makes it easier to insert the portion including first end 11.

[0048] The outer diameter at the first end 11 can be, for example, 1 / 20 or more, 1 / 15 or more, 1 / 10 or more, and 1 / 2 or less, 1 / 3 or less, 1 / 5 or less, etc., of the outer diameter at the second end 12.

[0049] 1, 5, 6, and 9, the outer diameter of the oral cavity insertion device 10 at the midpoint 13 in the longitudinal axis direction x is preferably smaller than the outer diameter of the oral cavity insertion device 10 at the second end 12. Since the midpoint 13 of the oral cavity insertion device 10 is a portion that is inserted deeper into the oral cavity 23 of the rodent 20 than the second end 12, the smaller outer diameter at the midpoint 13 makes it easier to insert the portion including the midpoint 13.

[0050] The outer diameter of the oral cavity insertion device 10 at the midpoint 13 can be, for example, 1 / 20 or more, 1 / 15 or more, 1 / 10 or more, or 1 / 2 or less, 1 / 3 or less, 1 / 5 or less, etc. of the outer diameter of the oral cavity insertion device 10 at the second end 12.

[0051] It is preferable that the outer diameter of the oral cavity insertion instrument 10 does not change from the first end 11 to the midpoint 13 in the longitudinal axis direction x. Here, "the outer diameter of the oral cavity insertion instrument 10 does not change" means that the rate of change in the outer diameter is 10% or less. The rate of change in the outer diameter may be 0%, or may be 0% or more and 5% or less, 3% or less, 2% or less, or 1% or less. This allows the portion of the oral cavity insertion instrument 10 from the first end 11 to the midpoint 13 to be more easily inserted deep into the oral cavity 23 of the rodent 20.

[0052] 4, in a state in which the oral cavity insertion device 10 is inserted into the oral cavity 23 of the rodent 20, the second end 12 is preferably positioned outside the mouth 21 of the rodent 20. This allows the teeth 22 of the rodent 20 to be stably supported by the oral cavity insertion device 10, thereby improving the protective effect of medical instruments such as the probe 30 placed in the inner cavity 10A of the oral cavity insertion device 10.

[0053] As an example of the above-mentioned configuration, the oral cavity insertion instrument 10 preferably has an expanded diameter portion 16 in which the inner cavity 10A expands in diameter from the first end 11 side to the second end 12 side on the second end 12 side of the midpoint 13 in the longitudinal axis direction x, as shown in Figs. 1 and 9. The expanded diameter portion 16 from the first end 11 side to the second end 12 side can conform to the shape of the mouth 21 from the back of the oral cavity 23 of the rodent 20 to the entrance of the mouth 21, and the oral cavity insertion instrument 10 can be easily placed in the oral cavity 23 of the rodent 20. In addition, since the medical instrument such as the probe 30 is inserted from the second end 12 on the expanded diameter side, it becomes easy to advance the medical instrument from the second end 12 side to the first end 11 side. When inserting the medical instrument from the second end 12 side into the mouth 21 of the rodent 20, it becomes easier to insert the medical instrument from any direction, making it easier to perform the procedure regardless of the skill or dominant hand of the user.

[0054] As shown in Figures 1, 5, and 6, the enlarged diameter portion 16 preferably has a maximum area of ​​the cavity 10A at the second end 12. Since the enlarged diameter portion 16 has a maximum area of ​​the cavity 10A at the second end 12, when the oral cavity insertion device 10 is inserted from the mouth 21 of the rodent 20, the oral cavity insertion device 10 can be inserted deeper into the oral cavity 23 while sliding the teeth 22 on the outer surface of the enlarged diameter portion 16, so that the teeth 22 can be easily positioned near the second end 12 where the cavity 10A has the maximum area. This makes it easier to protect medical instruments such as the probe 30 positioned in the cavity 10A of the oral cavity insertion device 10 from the teeth 22 while opening the mouth 21 of the rodent 20 to the maximum extent.

[0055] As shown in FIG. 9, the enlarged diameter portion 16 may be configured such that the area of ​​the cavity 10A is maximum on the first end 11 side rather than the second end 12 in the longitudinal axis direction x. In this case, the enlarged diameter portion 16 preferably has a region where the area of ​​the cavity 10A does not change proximal to the position where the area of ​​the cavity 10A is maximum. Here, "the area of ​​the cavity 10A does not change" means that the rate of change in the area of ​​the cavity 10A is 10% or less. The rate of change in the area may be 0%, or may be 0% or more and 5% or less, 3% or less, 2% or less, or 1% or less. With this configuration, when inserting the oral cavity insertion instrument 10 from the mouth 21 of the rodent 20, the tooth 22 can be inserted deep into the oral cavity 23 while sliding the tooth 22 on the outer surface of the enlarged diameter portion 16, and then the tooth 22 can be arranged in a region where the area of ​​the cavity 10A does not change. Therefore, the tooth 22 can be stably arranged on the outer surface of the oral cavity insertion instrument 10, and it is easy to prevent the oral cavity insertion instrument 10 from shifting.

[0056] Here, the area of ​​the lumen 10A is the cross-sectional area of ​​the lumen 10A in a cross section perpendicular to the longitudinal axis direction x at each position in the longitudinal axis direction x. In the configurations shown in Figs. 1, 5, and 6, the expanded diameter portion 16 has the largest area of ​​the lumen 10A at the second end 12, and therefore the opening 12A of the second end 12 constitutes the proximal end of the expanded diameter portion 16. In the configuration shown in Fig. 9, the cross-sectional area of ​​the lumen 10A in a cross section perpendicular to the longitudinal axis direction x is largest at a position closer to the first end 11 than the second end 12 in the longitudinal axis direction x, and the area of ​​the lumen 10A does not change from that position to the second end 12. In this configuration, it is also preferable that the opening 12A of the second end 12 constitutes the proximal end of the expanded diameter portion 16.

[0057] It is preferable that the area of ​​the cavity 10A of the oral cavity insertion instrument 10 gradually increases from the distal end to the proximal end of the enlarged diameter portion 16. This makes it easier to slide the teeth 22 along the outer surface of the enlarged diameter portion 16. It also makes it easier to advance a medical instrument such as a probe 30 disposed in the cavity 10A of the oral cavity insertion instrument 10 from the proximal side to the distal side of the enlarged diameter portion.

[0058] 5, the expanded diameter portion 16 may have a linear shape in a cross section taken along the longitudinal axis direction x. Alternatively, although not shown, the expanded diameter portion 16 may have a curved shape in a cross section taken along the longitudinal axis direction x, or may have both a linear shape and a curved shape.

[0059] In the longitudinal axis direction x, the length of expanded diameter portion 16 can be 20% or more, 30% or more, 50% or more, and 95% or less, 90% or less, 80% or less, 70% or less, etc., of the length from midpoint 13 to second end 12 of oral cavity insertion instrument 10. If the length of expanded diameter portion 16 in the longitudinal axis direction x is within the above range, the above effect can be achieved.

[0060] When the expanded diameter section 16 has a configuration in which the area of ​​the inner cavity 10A is maximum on the first end 11 side rather than the second end 12 in the longitudinal axis direction x, and the oral cavity insertion instrument 10 has a region where the area of ​​the inner cavity 10A does not change proximal to the expanded diameter section 16, the length of the region where the area of ​​the inner cavity 10A does not change in the longitudinal axis direction x can be 5% or more, 10% or more, 20% or more, or 70% or less, 60% or less, 50% or less, etc. of the length from the midpoint 13 to the second end 12 of the oral cavity insertion instrument 10. In addition, the length of the region where the area of ​​the inner cavity 10A does not change in the longitudinal axis direction x can be 3% or more, 5% or more, 10% or more, or 60% or less, 50% or less, 40% or less, etc. of the length of the expanded diameter section 16.

[0061] The oral cavity insertion tool 10 is preferably made of a resin. Examples of the resin constituting the oral cavity insertion tool 10 include fluorine-based resins, silicone-based resins, polyolefin-based resins, polyester-based resins, polyurethane-based resins, polyamide-based resins, and natural rubbers such as latex rubber. These may be used alone or in combination of two or more. If the oral cavity insertion tool 10 is made of a resin, the oral cavity insertion tool 10 can be softened when it is inserted from the mouth 21 to the oral cavity 23 of the rodent 20, so that the stress of the rodent 20 can be reduced. In addition, since the oral cavity insertion tool 10 is easy to manufacture at low cost, the oral cavity insertion tool 10 can be made disposable after each procedure, thereby improving the efficiency and accuracy of the procedure.

[0062] Alternatively, the oral cavity insertion instrument 10 may be made of a metal. Examples of metals constituting the oral cavity insertion instrument 10 include stainless steel, iron, copper, and aluminum. These may be used alone or in combination of two or more. If the oral cavity insertion instrument 10 is made of a metal, damage to the oral cavity insertion instrument 10 caused by contact with the teeth 22 of the rodent 20 can be easily prevented. This improves durability, and allows the oral cavity insertion instrument 10 to be washed and used repeatedly.

[0063] Alternatively, the oral cavity insertion instrument 10 may be made of resin and metal.

[0064] As described above, the oral cavity insertion device 10 can be used to prevent damage to medical instruments such as the probe 30 during procedures such as orally administering a substance to the rodent 20. In addition, the oral cavity insertion device 10 can reduce stress on the rodent 20 and allow the rodent 20 to open its mouth 21, making it easy to insert a medical instrument into the oral cavity 23 of the rodent 20 regardless of the skill or dominant hand of the surgeon performing the procedure. Furthermore, by securing an insertion passage using the oral cavity insertion device 10, it is possible to perform procedures such as inserting multiple medical instruments consecutively into the oral cavity 23 of the rodent 20 or inserting another medical instrument through a gap between the oral cavity insertion device 10 and the mouth 21 of the rodent 20. [Explanation of symbols]

[0065] 10: Oral insertion tool 10A: lumen 11: 1st end 11A: First end opening 12: 2nd end 12A: Opening at second end 12L: Long axis 12S: Short axis 13: Midpoint 15: Curved section 16: Expanded diameter part 20:Rodents 21: Mouth 22: Teeth 22a: upper teeth 22b: Lower teeth 23: Oral cavity 30 Sonde A: Plane A P: Perpendicular to plane A X: Central axis x: Longitudinal direction

Claims

1. A cylindrical oral cavity insertion device that is inserted into the mouth of a rodent, a lumen extending in a longitudinal direction; A curved portion; The catheter has a first end on a distal side and a second end on a proximal side in the longitudinal direction, The first end and the second end each have an opening communicating with the inner cavity, The shape of the opening at the second end has a major axis and a minor axis, and the minor axis extends in a range of −30° to +30° with respect to a plane A including a central axis of the curved portion.

2. The oral cavity insertion device according to claim 1 , wherein the major axis extends in a range of −30° to +30° with respect to a perpendicular line to the plane A.

3. 3. The oral cavity insertion device according to claim 1, wherein a ratio of the major axis to the minor axis (major axis / minor axis) is 1.1 or more and 3.5 or less.

4. The oral cavity insertion device according to claim 1 or 2, wherein an area of ​​the opening at the second end is larger than an area of ​​the opening at the first end.

5. The oral cavity insertion instrument according to claim 1 or 2, wherein an outer diameter of the oral cavity insertion instrument at the first end is smaller than an outer diameter of the oral cavity insertion instrument at the second end.

6. The oral cavity insertion instrument according to claim 1 or 2, wherein an outer diameter of the oral cavity insertion instrument at a midpoint in the longitudinal direction is smaller than an outer diameter of the oral cavity insertion instrument at the second end.

7. The oral cavity insertion instrument according to claim 1 or 2, further comprising an increased diameter portion, the inner diameter of which increases from the first end side to the second end side, on the second end side of a midpoint in the longitudinal axis direction.

8. The oral cavity insertion instrument according to claim 7 , wherein the area of ​​the inner cavity of the expanded diameter portion is maximized at the second end.

9. The oral cavity insertion instrument according to claim 7 , wherein the area of ​​the inner cavity of the expanded diameter portion is greatest on a side of the first end relative to the second end in the longitudinal axis direction.

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