Method for treating combined transverse and vertical skeletal malocclusions

Abstract

FIELD: maxillofacial orthognathic surgery.SUBSTANCE: treatment of combined transverse and vertical skeletal malocclusions. Under endotracheal anesthesia, through the upper vault of the oral vestibule, incisions are made in the mucous membrane and periosteum, the alveolar process of the maxilla, the zygomaticoalveolar ridge, the anterior wall of the maxillary sinus, the lateral edge of the piriform aperture, and the inferior nasal passage on the right and left are skeletonized. A linear osteotomy of the upper jaw is performed according to Le Fort of the lower type on the right and left with the intersection of buttresses, through the lower nasal passages on the right and left. A parasagittal osteotomy of the palatine suture is performed parallel to the nasal septum along 2 / 3 of the hard palate from the distal part, the edges of the piriform aperture are ground on the right and left along the cut according to the Le Fort lower type to the projection of the roots of the teeth at the beginning of the double occlusal plane of the open bite in the anterior section. Then, parallel to the roots of these teeth on the right and left, a saw is inserted through the ground areas of the bone, parasagittal cuts are made in the alveolar process, converging to the previously performed parasagittal cuts in the distal parts of the upper jaw parallel to the nasal septum. Using a chisel, an osteotomy of the nasal septum in the anterior section is performed with multisegmentation of the upper jaw into 2 lateral and 1 central tooth-containing fragments, an extraosseous distraction device is installed with fixation in the lateral fragments, 2 orthodontic mini-implants are fixed in the central fragment between the central and lateral incisors and 2 orthodontic mini-implants are fixed on the lower jaw in the anterior section between the roots of the teeth. The active period of distraction of the lateral fragments and lowering of the central fragment begins on the 5th day from the moment of surgery by activating the expansion apparatus and placing elastic traction between orthodontic mini-implants on the upper and lower jaws. The distraction device is activated by rotating the expansion screw 90 degrees once daily, and the elastic bands are replaced once daily. Device activation and band replacement continue for 2 to 5 weeks, transitioning to the retention phase of treatment.EFFECT: method allows to reduce the duration and stages of complex treatment of combined transverse and vertical anomalies of the upper jaw, and to shorten the rehabilitation period.1 cl, 7 dwg, 1 ex

Description

[0001] The invention relates to the field of medicine, namely to maxillofacial orthognathic surgery, and can be used to treat combined transverse and vertical skeletal malocclusions - narrowing of the upper jaw and open bite in the anterior region.

[0002] Various methods of cutting the palatal suture are known for the correction of maxillary narrowing using surgically assisted expansion. The first option is a single midline cut between the roots of the central incisors with osteotomy of the nasal septum (Northway WM, Meade JB Jr. Surgically assisted rapid maxillary expansion: a comparison of technique, response, and stability. Angle Orthod. 1997;67(4):309-20.). The second option: a paramedian cut relative to the nasal septum and the converging roots of the central incisors into one median (Y-shaped cut) (Landes CA, Laudemann K, Petruchin O, Mack MG, Kopp S, Ludwig B, Sader RA, Seitz O. Comparison of bipartite versus tripartite osteotomy for maxillary transversal expansion using 3-dimensional preoperative and postexpansion computed tomography data. J Oral Maxillofac Surg. 2009 Oct;67(10):2287-301).The third option: parasagittal cut of the alveolar process between the central and lateral incisors on the right and left with their continuation along the palatal suture (Landes CA, Laudemann K, Petruchin O, Revilla C, Seitz O, Kopp S, Ludwig B, Sader RA. Advantages and limits of 3-segment (paramedian) versus 2-segment (median) surgically assisted rapid maxillary expansion (SARME). Oral Surg Oral Med Oral Pathol Oral Radiol. 2012 Jan;113(l):29-40.). Treatment of skeletal vertical anomalies - open bite in the anterior region occurs at the subsequent orthodontic (decompensation of the bite on segmented arches in the area of ​​the double occlusal plane) and second surgical (multisegmentation and movement of segments of the upper jaw) stages (Hoshijima M, Oka N, Matsumura T, Iida S, Kamioka H. Treatment of Severe Open Bite Malocclusion with Four-Piece Segmental Horseshoe Le Fort I Osteotomy. Acta Med Okayama. 2023 Feb;77(l):97-104).

[0003] The disadvantage of correcting combined dentofacial anomalies in the transverse and vertical planes using the described methods is that their treatment is carried out at different stages, thereby prolonging the rehabilitation period.

[0004] The technical result of the invention is the parallel normalization of the transverse parameters of the upper jaw and the elimination of the double occlusal plane of the open bite in the anterior section after hardware-surgical expansion of the upper jaw in one stage, reducing the rehabilitation period.

[0005] The technical result is achieved in a method for treating combined transverse and vertical skeletal malocclusions, characterized by the fact that in the case of combined narrowing of the upper jaw and an open bite in the anterior section, the patient, under endotracheal anesthesia, through the upper vault of the oral vestibule, makes incisions in the mucous membrane and periosteum, skeletonizes the alveolar process of the upper jaw, the zygomaticoalveolar ridge, the anterior wall of the maxillary sinus, the lateral edge of the piriform aperture, the lower nasal passage on the right and left, performs a linear osteotomy of the upper jaw according to Le Fort of the lower type on the right and left with the intersection of buttresses, through the lower nasal passages on the right and left, performs a parasagittal osteotomy of the palatine suture parallel to the nasal septum along 2 / 3 of the hard palate from the distal part,the edges of the pear-shaped aperture are ground on the right and left along the cut according to Le Fort of the lower type to the projection of the roots of the teeth at the beginning of the double occlusal plane of the open bite in the anterior section, then a saw is inserted parallel between the roots of these teeth on the right and left through the ground areas of the bone, parasagittal cuts are made in the alveolar process, converging to the previously performed parasagittal cuts in the distal sections of the upper jaw parallel to the nasal septum, using a chisel, an osteotomy of the nasal septum is performed in the anterior section with multisegmentation of the upper jaw into 2 lateral and 1 central tooth-containing fragments, an extra-osseous distraction device is installed with fixation in the lateral fragments, 2 orthodontic mini-implants are fixed in the central fragment between the central and lateral incisors and 2 orthodontic mini-implants on the lower jaw in the anterior section between roots of teeth,The active period of distraction of the lateral fragments and lowering of the central fragment begins on the 5th day after the operation by activating the expansion device and placing elastic traction between the orthodontic mini-implants on the upper and lower jaws, while the activation of the distraction device is carried out in the mode of 1 turn of the expansion screw by 90 degrees per day, a pair of elastic traction is changed once a day; activation of the device and change of traction continue from 2 to 5 weeks and move into the retention phase of treatment.

[0006] The conducted studies have shown that with the onset of distraction osteogenesis with the activation of the expansion apparatus from the 5th day after the operation, in combination with the appointment of elastic traction between orthodontic mini-implants of the central fragment of the upper jaw and the lower jaw, there is a correction of both the narrowing of the upper jaw due to the hardware expansion of the lateral fragments, and a correction of the open bite in the anterior section due to the intermaxillary traction of the central fragment and the distraction of the lateral fragments.

[0007] The method is illustrated in Fig. 1-7, where:

[0008] Fig. 1 shows a diagram of the parasagittal cut of the alveolar process of the maxilla, the cut according to Le Fort of the lower type, osteotomy of the nasal septum, areas of grinding the bone of the piriform aperture, installation of orthodontic mini-implants and the vector of intermaxillary elastic traction in the coronal projection;

[0009] Fig. 2 shows a diagram of the parasagittal cut of the alveolar and palatine processes of the maxilla, the horizontal plate of the palatine bone; osteotomy of the pterygomaxillary joints and the anterior third of the nasal septum, areas of grinding of the bone of the piriform aperture in axial projection from the side of the nasal cavity;

[0010] Fig. 3 shows a diagram of the parasagittal cut of the alveolar and palatine processes of the maxilla, the horizontal plate of the palatine bone; osteotomy of the pterygomaxillary joints, installation of an expansion apparatus, the vector of distribution of distraction forces and expansion zones of the maxilla in axial projection from the oral cavity;

[0011] in Fig. 4 - intraoperative photograph of the ground edge of the pear-shaped aperture, horizontal cut according to Le Fort of the lower type, parasagittal cut of the alveolar process;

[0012] in Fig. 5 - the condition of the dental arches before and after a month of instrumental expansion of the lateral fragments of the upper jaw and lowering of the central fragment on intermaxillary elastic traction from the moment of surgery;

[0013] Figs. 6 and 7 show a comparison of pre- and postoperative CBCT scans. Coronal projection. Bone changes after surgery are shown in blue.

[0014] Designation:

[0015] 1 - Cutting a bone with a saw;

[0016] 2 - Grinding the bone with a bur;

[0017] 3 - Elastic traction;

[0018] 4 - Vector of lowering the central fragment;

[0019] 5 - Lateral fragment distraction vector.

[0020] 6 - Condition before surgery.

[0021] 7 - Condition after surgery.

[0022] The method is carried out, for example, as follows. Under endotracheal anesthesia, the patient is given access through the superior vault of the oral vestibule. Incisions are made in the mucous membrane and periosteum 0.5 cm from the transitional fold in the projection of teeth 15-12 and 22-25. The alveolar process of the maxilla, the zygomaticoalveolar ridge, the anterior wall of the maxillary sinus, the lateral edge of the pyriform aperture, and the inferior nasal meatus on the right and left are skeletonized. A gentle linear osteotomy of the upper jaw according to Le Fort type I of the lower type is performed on the right and left with intersection of the buttresses using a reciprocating saw. A parasagittal osteotomy of the palatal suture is performed through the inferior nasal meatuses on the right and left, parallel to the nasal septum, extending 2 / 3 of the hard palate from the distal part.Using a spherical carbide bur, grind down the two edges of the pear-shaped aperture on the right and left sides along the lower Le Fort cut to the projection of the roots of the teeth where the double occlusal plane of the anterior open bite begins (e.g., between the first premolar and canine or between the canine and lateral incisor on the right and left sides). Then, parallel to the roots of these teeth on the right and left sides, inserting the saw through the ground areas of bone, parasagittal cuts are made in the alveolar process, converging with the previously performed parasagittal cuts in the distal sections of the maxilla parallel to the nasal septum. Using a chisel, an osteotomy of the anterior nasal septum is performed, thereby achieving gentle multisegmentation of the maxilla into three tooth-containing fragments: two lateral and one central.A bone-based distraction device is installed with fixation in the lateral fragments, two orthodontic mini-implants are fixed in the central fragment between the central and lateral incisors, and two orthodontic mini-implants are fixed in the mandible in the anterior region between the roots of the teeth. The active period of distraction of the lateral fragments (5) and lowering of the central fragment (4) begins on the fifth day after surgery by activating the expansion device and placing elastic traction devices (3) between the orthodontic mini-implants in the upper and lower jaws. The distraction device is activated by rotating the expansion screw 90 degrees once per day. The pair of elastic traction devices is replaced once per day. Device activation and traction device replacement lasts from 2 to 5 weeks, depending on the achievement of the required skeletal parameters.Upon completion of the active phase, a control CBCT scan is performed and the transition to the retention phase is initiated by preserving the expansion screw with a filling material, installing brackets on a solid round arch, and placing lower-strength interdental traction devices between the central fragment of the maxilla. At the end of the retention period (3 months) following the control CBCT scan, the device is removed, and the intermaxillary traction devices are discontinued.

[0023] The essence of the method is confirmed by a clinical example.

[0024] Patient B., 31, presented to the Maxillofacial Surgery Center of the Institute of Beauty in May 2024 complaining of an unattractive facial appearance, unattractive smile, and malocclusion. Her medical history revealed no previous orthodontic treatment. She was diagnosed with a transverse maxillary arch (SMA), distal anterior open bite, buccal crossbite, and maxillary constriction. In July 2024, surgery was performed using the proposed technique (parasagittal alveolar ridge cuts were performed between the canines and lateral incisors on the right and left). The active period of expansion of the lateral fragments and reduction of the central fragment lasted 2 weeks. The retention period was 3 months. As a result of treatment from July to October 2024, the transverse discrepancy in the maxillary width was corrected, and the anterior open bite was eliminated. The patient continues orthodontic decompression treatment to undergo subsequent surgery to correct sagittal anomalies.

[0025] In this study, 30 parasagittal osteotomies of the palatine suture and alveolar process were performed using the claimed method between August 2016 and August 2025. All patients underwent resurfacing of the pyriform aperture on the right and left. All patients underwent osteotomy of the anterior nasal septum.

[0026] All patients underwent distraction of the lateral fragments of the maxilla with a bone expander apparatus for 2-5 weeks postoperatively, and lowering of the central fragment of the maxilla using elastic intermaxillary traction devices with skeletal support on orthodontic mini-implants. All patients maintained a retention regimen of wearing the device and intermaxillary traction devices for 3 months from the completion of the active treatment period. All patients underwent follow-up CBCT examinations immediately postoperatively, at the end of the active treatment phase, at the end of the retention phase, and at the end of the long-term results. All patients demonstrated stable resolution of the maxillary narrowing and anterior open bite, both in the combined treatment phase and at the first stage of complex treatment.

[0027] Thus, the claimed method allows to reduce the duration and stages of complex treatment of combined transverse and vertical anomalies of the upper jaw, and to shorten the rehabilitation period.

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