Surgical-orthodontic Correction Research Articles

Biomechanical rationale for surgical-orthodontic expansion of the adult maxilla

Objective: To develop a biomechanical rationale for surgical-orthodontic correction of transverse maxillary deficiencies in adults by clarifying the internal stress responses to rapid palatal expansion in a photoelastic model. Materials and Methods: A three-dimensional photoelastic analog of an adult human skull was constructed by fabricating the individual facial bones from a photoelastic material and fixing them along their anatomic sutural areas. After determining the force-activation characteristics of a Hyrax expansion appliance in a straining frame, the appliance was applied to the analog and incrementally activated. The stresses developing at the different craniofacial areas were visualized and photographed in the field of a circular polariscope. Sequential cuts were performed to simulate midpalatal, zygomatic buttress, and pterygomaxillary osteotomies, and the alterations in the internal stress responses were recorded after each individual cut. Results: The force-activation characteristics of the Hyrax appliance are in the orthopedic range (500 g). The magnitude and distribution of the stresses induced by appliance activation differed notably between the simulated osteotomies. Analysis of fringe patterns showed that the midpalatal and pterygomaxillary articulations were the primary anatomic sites of resistance to expansion forces. The patterns of distribution and the increase in the magnitude of the stresses at superior sutural location were particularly pronounced after the pterygomaxillary cuts. The forces produced by the Hyrax appliance had deep anatomic effects, with internal stresses also manifesting at regions distant from the site of force application. Conclusions: Based on photoelastic observation, it may be concluded that complete midpalatal and pterygomaxillary osteotomies are essential for predictable skeletal expansion in adults. Exclusive use of bilateral zygomatic buttress osteotomies appears to be inadequate. The expansion forces exerted by the Hyrax appliance are orthopedic in nature and produce deep anatomic effects. Clinicians should be aware that the craniofacial stresses produced by appliance activation may be experienced by the patient as pain or discomfort.

An American Board of Orthodontics case report: The orthodontic-surgical correction of a Class I malocclusion with high mandibular plane angle, bimaxillary protrusion, and vertical maxillary excess

This is the case report of a 26-year-old black woman with a Class I malocclusion and a skeletal Class II profile and vertical maxillary excess. Extraction spaces were closed, creating a Class II malocclusion to augment anticipated surgery (LeFort I osteotomy and genioplasty). The treatment result provided outstanding occlusal function and optimal facial esthetics. Attention to detail was mandatory, i.e., identify the patient's chief complaint, provide treatment options to resolve the complaint, and treat and maintain the dentition as ideally as possible. [This case was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process conducted by the Board.]

The effects of surgical-orthodontic correction of skeletal class III malocclusion on mandibular movement

The effects of surgical-orthodontic treatment on mandibular movement were studied using the mandibular kinesiograph in 30 patients with skeletal class III malocclusion that was corrected by the sagittal split osteotomy (27 patients), a combination of the sagittal split osteotomy and body ostectomy (2 patients), or the sagittal split osteotomy and a posterior alveolar osteotomy of the maxilla (1 patient). Postoperatively, the mean maximum anterior and posterior excursions of the mandible increased significantly from 4.1 to 6.7 mm and from 0.6 to 2.6 mm, respectively. The lateral excursion to the right and left sides also showed significant increases from 4.8 to 7 mm and from 5.5 to 7 mm, respectively, after surgery. In analysis of the habitual and rapid opening and closing movements of the mandible, marked impairment was not observed in most patients except for crossing and discrepancy in the tracings of the habitual opening and closing movements in the sagittal plane observed in 11 patients. These findings were observed in only one patient postoperatively. The results indicate that the surgical orthodontic correction of skeletal class III malocclusion has favorable effects on the function of the mandible.

成長ホルモン産生下垂体腺腫に伴う下顎前突症に対する１治験例

We presented an outline of a surgical orthodontic correction which we performed for an acromegalic patient whose serum growth hormone (GH) was not controlled enough after removal of pituitary adenoma.The patient was a 35-years-old male on the first visit. Under the diagnosis of pituitary adenoma, the tumor removal was performed in September 1986. In our clinic, we performed tongue reduction on 7 June 1988 and Obwegeser-Dal Pont method on 14 March 1989, even though his serum GH was not controlled enough at that time.In this case there were no complications during operation and postoperative period. 21 months have passed postoperatively. There has not been a relapse, and his feature and occlusal function remain in good condition.

Simultaneous Orthognathic and Cosmetic Neck Surgery

SUMMARY The patient population undergoing surgical-orthodontic correction of dentofacial deformities is becoming both older and more discriminating. As such, they often express a'desire for or request specific aesthetic as well as functional improvements. In an effort to improve the appearance of treatment results and to better meet the desires of patients undergoing orthognathic surgery, adjunctive cosmetic surgical procedures are becoming more commonplace. In our experience, one of the more frequently performed adjunctive procedures is cosmetic neck surgery. A multitude of cosmetic procedures have been advocated for aesthetic improvement of the fat-ridden or aging neck.1“6-n-w This article will discuss the relative indications for simultaneous orthognathic and cosmetic neck surgery, the basic techniques for cosmetic improvement of the fat or aging neck, and their respective results and complications.

Case report MM. Surgical-orthodontic correction of bilateral buccal crossbite (Brodie syndrome)

A surgical approach to treatment was required for this 35-year-old patient to correct a malocclusion characterized by a bilateral buccal crossbite. Surgical procedures included a LeFort 1 osteotomy to reduce maxillary width and correct the vertical asymmetry. The mandible was lengthened with a bilateral sagittal split osteotomy. Treatment options for the nongrowing patient are limited in the correction of severe skeletal disharmonies.

Surgical orthodontic correction of mandibular deficiency by sagittal osteotomy: Clinical and cephalometric analysis of 1-year data

A homogeneous sample of 76 mandibular retrognathic patients (mean age, 28 years) were examined for postoperative alterations after surgical treatment by bilateral sagittal split osteotomy and mandibular advancement with wire fixation. Skeletal and dental measures were obtained from preoperative, immediate postoperative, fixation-release, and 1-year cephalograms. Spearman correlation was used as a preliminary analysis to assess the relationship between postsurgical change and age, genioplasty, amount of mandibular advancement, and preoperative mandibular plane angle. Genioplasty and amount of mandibular advancement were included as independent factors in the subsequent repeated-measures analysis of variance, since these were the only two factors that showed a consistent trend of correlations with postoperative change. Genioplasty was a significant factor in the X and Y coordinate changes in pogonion, while the amount of mandibular advancement was a significant factor in the X coordinate movements of all mandibular landmarks except gonion and condylion. The mean amount of horizontal advancement was 5.2 mm, and anterior face height increased 5.1 mm. During fixation, B point moved posteriorly ( x = −1.6 mm, p < 0.01) and inferiorly ( y = 1.0 mm, p < 0.01) . After fixation release, these trends were reversed, resulting in a nonsignificant net horizontal change ( x = −0.5 mm, p = 0.10) and a significant net superior movement ( y = −1.3 mm, p = 0.01) by 1 year. Pogonion, menton, and mandibular incisor tip showed similar patterns. These findings support previous reports that horizontal relapse occurs during fixation but suggest that, at least in this sample of patients who underwent isolated mandibular advancement with or without genioplasty, these trends are reversed after fixation release, resulting in minimal net mean skeletal and dental change at 1 year after surgery.

Satisfaction of patients following surgical-orthodontic correction of skeletal class III malocclusions

To assess whether patients were satisfied with the results of treatment, questionnaires were sent to 65 patients who had undergone either the extraoral curved oblique osteotomy or the sagittal split osteotomy for correction of skeletal Class III malocclusions. Seventy-eight per cent of the patients answered that they were satisfied with the results in regard to their chief problems and 75% had improved masticatory function. A favorable change in appearance was recognized by 33 patients, whereas 30 patients noticed no major changes. Factors affecting satisfaction with the results are discussed.

Maxillary expansion: A surgical technique based on surgical-orthodontic treatment. Objectives and anatomical considerations

Summary Maxillary transverse expansion is usually done as an ancillary, not primary surgical movement in the surgical-orthodontic correction of dentofacial deformities. A maxillary osteotomy technique is described which permits combinations of movements, including expansion. Releasing the palatal soft tissue to disperse the resulting soft tissue tension, bone grafting and adequate stabilization and retention of the segments are stressed to achieve success. Also described is the use of local bone grafts and the rotation of soft tissues to cover surgical defects. Results are encouraging and the complication rate has been low in this series of 104 patients.

開こう症および下がく前突症のこう合治療に関する筋電図学的研究 観血的こう合改善手術を行った症例について

開こう症および下がく前突症のこう合治療に関する筋電図学的研究 観血的こう合改善手術を行った症例について

Maxillary expansion: A surgical technique based on surgical-orthodontic treatment objectives and anatomical considerations

Maxillary transverse expansion is usually done as an ancillary, not primary surgical movement in the surgical-orthodontic correction of dentofacial deformities. A maxillary osteotomy technique is described which permits combinations of movements, including expansion. Releasing the palatal soft tissue to disperse the resulting soft tissue tension, bone grafting and adequate stabilization and retention of the segments are stressed to achieve success. Also described is the use of local bone grafts and the rotation of soft tissues to cover surgical defects. Results are encouraging and the complication rate has been low in this series of 104 patients.

Surgical Orthodontic Correction of Transverse Maxillary Deficiency

Surgical Orthodontic Correction of Transverse Maxillary Deficiency

Surgical orthodontic correction of transverse maxillary deficiency: a simplified approach.

Osteotomy of the zygomaticomaxillary buttress in combination with a rapid palatal exapnsion appliance is a dependable technique for the treatment of horizontal maxillary deficiency in adults. This procedure has been used in 18 patients with excellent expansion in 17. In one patient, expansion was discontinued prior to overcorrection because of pressure necrosis on the palate related to the appliance. This was the only complication. The procedure is indicated mainly in those patients with a horizontal deficiency who do not require subsequent surgery, but for some patients it may be the preliminary procedure. Three patients in this series had subsequent orthognathic surgery. Follow-up has been from 1 to 6 years, and there has been no relapse. In our opinion, the zygomaticomaxillary buttress is the primary area of resistance to lateral movement of the maxilla by rapid maxillary expansion appliances.

The surgical-orthodontic correction of mandibular deficiency. Part II

As discussed in Part I of this study, persons with mandibular deficiency and Class II malocclusions exhibit a wide spectrum of esthetic, cephalometric, and occlusal characteristics. In many such patients optimal overall results are best obtained via a combined orthodontic-surgical approach. In such patients a critical evaluation is essential to decide (1) the optimal operation and (2) the appropriate orthodontic-surgical sequencing. Our method of making these two basic decisions was presented in Part I. In this article the indications for mandibular advancement with or without genioplasty, total subapical mandibular advancement, superior repositioning of the maxilla, and inferior repositioning of the maxilla are discussed in detail. These alternatives are illustrated with representative cases, and the results are discussed. The intention of these two presentations is to illustrate an orthodontic-surgical approach to the correction of mandibular deficiency and Class II malocclusion that is predicated on a systematic evaluation of the individual patient rather than a standard approach.

The surgical-orthodontic correction of mandibular deficiency. Part I

Persons with mandibular deficiency and Class II malocclusions have a spectrum of esthetic, skeletal, and occlusal characteristics. In many of these patients optimal overall results are best obtained via a combined orthodontic-surgical approach. In such cases a critical patient evaluation is essential to decide (1) the optimal operation and (2) the appropriate orthodontic-surgical sequencing. In Part I of this article our method of making these two basic decisions is presented, the decisions being predicated upon achieving optimal esthetic, functional, and stable results. In addition, two of the possible orthodontic-surgical approaches—the augmentation genioplasty and the anterior maxillary ostectomy are discussed in detail. These approaches are illustrated with representative cases. In Part II of the article additional options for combined orthodontic surgical-management of this patient population will be discussed.

Surgical orthodontics and the temporomandibular joint: II. Mandibular advancement via modified sagittal split ramus osteotomies

Ten randomly selected adults who had undergone orthodontic treatment and isolated mandibular advancement for correction of mandibular deficiency were evaluated clinically and radiographically (mean, 42.8 months postsurgery) for signs and symptoms of masticatory and temporomandibular joint dysfunction. A three-part evaluation of the subjects was performed. This consisted of an anamnestic evaluation, a clinical examination, and a radiographic examination. The anamnestic evaluation (previous medical history) revealed that prior to surgical intervention 20 percent ( 2 10 ) of the patients noted the presence of facial pain which we believed was localized to the masticatory musculature. The pain was reported to have resolved postoperatively. No patients reported the presence of pain in their temporomandibular joints prior to surgical treatment. However, three patients related a history of postoperative facial and joint pain that had not existed preoperatively and had not resolved at the time of follow-up examination. Temporomandibular joint sounds were not reported by any of the patients preoperatively. Immediately after release of intermaxillary fixation, 50 percent ( 5 10 ) of the patients noticed temporomandibular joint sounds. Two of these patients noted a resolution of the joint sounds without treatment, while the remaining three patients reported the presence of joint sounds at the time of re-examination. Further, these were the three patients who had a history of unresolved postoperative facial and joint pain. Clinical examination of the temporomandibular joints at the time of recall evaluated the range of mandibular movements and the presence of joint pain or sounds during function. These examinations revealed that measures of mandibular movements were somewhat below normal. Three patients demonstrated combined ipsilateral joint and masticatory muscle pain during mandibular function, upon contralateral masticatory loading, and in response to palpation. These were the same patients who reported persistent pain and joint sounds during the anamnestic evaluation. Thirty-five percent ( 7 20 ) of the joints demonstrated sounds (popping or crepitation) via auscultation during jaw opening or closing. One joint demonstrated popping during contralateral masticatory loading. Cephalometric laminograms were obtained of each of the twenty joints with the mandible in three positions: maximum intercuspation, mandibular rest position, and maximal opening. Various anatomic measurements were quantitated from these radiographs and three parameters—condylar position, condylar movement, and incidence of arthrosis—were compared to normative data obtained from the literature. All parameters evaluated were compared with those of a group of patients who had undergone superior repositioning of the maxilla. 1 When compared to normal, it was found that persons who had undergone mandibular advancement surgery demonstrated (1) a relatively retropositional location of the condyle within the glenoid fossa and (2) reduced condylar movement during maximal mandibular opening. These joints exhibited a greater incidence of arthrosis when compared to those of normal persons. When compared to the patients who had undergone superior maxillary repositioning, the primary radiographic differences were found to be (1) a greater reduction in condylar movement in the maxillary surgery group and (2) higher incidence of arthrosis in the group of patients who had undergone mandibular advancement surgery. 1 These findings demonstrate the need for more critical prospective clinical and radiographic evaluation of patients prior to surgical-orthodontic correction of mandibular deficiency.

Surgical orthodontics and the temporomandibular joint: I. Superior repositioning of the maxilla

Ten randomly selected adults who had undergone orthodontic treatment and isolated superior repositioning of the maxilla for vertical maxillary excess (VME) were evaluated clinically and radiographically (mean, 48.7 months postsurgery) for signs and symptoms of masticatory and temporomandibular joint dysfunction. The patients ranged from 18 years to 37 years of age (mean, 26.2 years) when evaluated. A three-part evaluation of the subjects was performed. This consisted of an anamnestic evaluation (previous medical history), a clinical examination, and a radiographic evaluation. The anamnestic evaluation revealed that, prior to surgery, facial pain was reported by one patient and was not present in any of the patients upon follow-up examination. We believed that the pain was not related to the masticatory musculature and/or the temporomandibular joint. No patients reported pain or sounds in their joints preoperatively, while 30 percent ( 3 10 ) of the patients related a history of temporomandibular joint sounds immediately after release of intermaxillary fixation, which subsequently was reported to have resolved in all instances without treatment. Clinical examination of the temporomandibular joints at the time of recall evaluated mandibular movements and the presence of pain or sounds during joint function. These examinations revealed that clinical measures of mandibular movements were somewhat reduced relative to normal. All patients were free of temporomandibular joint and masticatory muscle pain during function, upon contralateral masticatory loading, and upon palpation. Fifteen percent ( 3 20 ) of the joints examined demonstrated sounds (popping or crepitation) via auscultation. Masticatory loading in the contralateral premolar region did not induce noise in any of the joints examined. Cephalometric laminagraphic radiographs were obtained of each of the twenty temporomandibular joints with the mandible in three positions; maximum intercuspation, mandibular rest position, and maximal opening. Numerous anatomic relations were quantified from these radiographs. However, only three parameters (condylar position, movement, and evidence of arthrosis) were compared to normative data available in the literature. These comparative data suggested that persons who had undergone orthodontic treatment in conjunction with superior maxillary repositioning demonstrated (1) a relatively retropositional condyle within the fossa and (2) reduced condylar movement during maximal mandibular opening. Two of twenty temporomandibular joints demonstrated radiographic evidence of arthrosis; one condyle demonstrated articular surface erosions, and another exhibited articular surface sclerosis. The overall incidence of arthrosis was not much greater than normal, with 20 percent ( 4 20 ) of the joints demonstrating a reduced interarticular joint space. Overall, the clinical findings revealed a low incidence of pathologic masticatory muscle and temporomandibular joint symptoms and signs compared to normative data in the literature. However, the cephalometric laminographic findings suggest the need for prospective evaluation of the temporomandibular joints in persons undergoing surgical-orthodontic correction of vertical maxillary excess.

2 Maxillary Protrusion Cases Treated with Surgical-Orthodontic Correction

2 Maxillary Protrusion Cases Treated with Surgical-Orthodontic Correction

Surgical inferior repositioning of the maxilla: Treatment considerations and comprehensive management

Despite numerous technical and biologic advances in the surgical-orthodontic correction of dentofacial deformities, inferior repositioning of the hypoplastic and/or deficient maxilla remains disturbingly unpredictable. Factors contributing to the success or failure of this surgical procedure have heretofore been poorly defined. This article reviews the salient clinical features, discusses the relevant treatment considerations, and prescribes a specific regimen for stable surgical inferior repositioning of the maxilla in persons with true vertical maxillary deficiency.

The influence of mandibular advancement via modified sagittal split ramus osteotomy on the masticatory musculature

The modifications of the sagittal split ramus osteotomy have been introduced to optimize vascularity to the proximal segment and minimize the influence of the masticatory musculature on relapse following the surgical-orthodontic correction of mandibular deficiency. The biologic basis for increased vascularity in comparison to conventional techniques has been proved. This study was done to evaluate the influence of the modified sagittal split ramus osteotomy on the masticatory musculature following surgical advancement of the mandible. The kinesiometric and electromyographic findings in five adults who underwent surgical advancement of the mandible reveal that surgical advancement of the mandible via modified sagittal split ramus osteotomy does not significantly influence muscles of mastication.