Comparison of the clinical outcomes of patients having sounds in the temporomandibular joint with skeletal mandibular deformities treated by vertico-sagittal ramus osteotomy or vertical ramus osteotomy

Improvement of the temporomandibular joint symptoms due to the condylar position change following modified L-shaped intraoral vertico-sagittal ramus osteotomy: a single-center, retrospective study

PURPOSE

Intraoral vertico-sagittal ramus osteotomy (IVSRO) was first reported by Choung in 1992 as a surgical procedure to decrease postoperative condylar dislocation. In 2017, Iwanaga et al. developed modified L-shaped IVSRO (mIVSRO) to reduce postoperative nerve dysfunction and achieved favorable outcomes. This study aimed to clarify the effect of mIVSRO on changes in temporomandibular joint (TMJ) symptoms and three-dimensional condylar position.

METHODS

We conducted a retrospective study of thirty sides in fifteen Japanese adults diagnosed with jaw deformities who underwent mIVSRO and sagittal split ramus osteotomy (SSRO). TMJ symptoms were assessed chronologically, and the condylar long axis and the condylar position were analyzed two- and three-dimensionally using axial cephalograms and cone-beam computed tomography.

RESULTS

Postoperative TMJ symptoms improved by 90% (9/10 sides) in the mIVSRO group and by 50% (7/14 sides) in the SSRO group. The mIVSRO group exhibited outward rotation of the condylar long axis, while the SSRO group exhibited inward rotation. Moreover, mIVSRO induced residual anteromedial-inferior deviation of the condyle. The inclination angle of the condylar process was not significantly different between the two procedures pre- and postoperatively.

CONCLUSION

These results clearly demonstrated the effect of mIVSRO on symptomatic TMJ. Residual changes in the position of the condyle following mIVSRO may not affect jaw function.

Surgical Management of Laterognathia in Orthofacial Surgery

INTRODUCTION

Each year around the world, various surgical procedures are carried out with the goal of correcting laterognathia; both the intraoral vertical ramus osteotomy (IVRO) and bilateral sagittal split ramus osteotomy (OSB) have been the most used techniques in mandibular surgery. These techniques have advantages and disadvantages; for example the advantages of the OSB include: increased coefficient of friction between bony segments, for both the forward and the retroposition, as well as decrease in the time of intermaxillary fixation (IMF). Disadvantages include injury to the inferior alveolar nerve (IAN), hemorrhage, bad split, among others. The advantages of IVRO include decrease of possibility of injury to the IAN, ease of implementation of the technique, a lower incidence of hemorrhage and the short duration of the surgical procedure. Their disadvantages include: lower coefficient of friction between bony segments, requires a relatively long period of IMF. The combination between the techniques of mandibular osteotomy for the correction of minor 10 mm laterognathia is the ideal treatment, since it avoids potential recurrence.

MATERIALS AND METHODS

We describe two cases of patients with laterognathia greater than 6 mm associated with maxilla deformity, which were treated with combined osteotomies. At Maxillofacial Surgery Service, Specialty Hospital, National Medical Center XXI Century, we describe the advantages and disadvantages, pre and postoperative nosocomial, by comparing them with the reports of the literature.

CONCLUSION

The combination of techniques in the correction of laterognathias greater than 4 mm (smaller than 10 mm) is the ideal treatment, eliminating problems of articular compression, recurrence and damage to the alveolar nerve.

The different effects of intraoral vertical ramus osteotomy (IVRO) and sagittal split ramus osteotomy (SSRO) on mandibular border movement

OBJECTIVES

This study investigated the different effects of intraoral vertical ramus osteotomy (IVRO) and sagittal split ramus osteotomy (SSRO) on mandibular border movement.

METHODS

The participants included 22 patients receiving IVRO and 22 patients receiving SSRO who were treated at Okayama University Hospital. Their mandibular border movement was evaluated in three dimensions with 6° of freedom using an optical recording system.

RESULTS

A strong correlation between condylar and lower incisor movement was observed during maximum jaw protrusion and laterotrusion. Significant improvements in condylar and lower incisor movement were detected after orthognathic surgery during maximum jaw protrusion and laterotrusion in the IVRO group and during maximum jaw protrusion in the SSRO group.

DISCUSSION

IVRO likely achieves greater improvement in jaw movement than SSRO. Therefore, the application of IVRO could be considered in the treatment of patients with jaw deformities featuring temporomandibular joint problems.

The study of position of antilingula, midwaist of mandibular ramus and midpoint between coronoid process and gonion in relation to lingula of 92 Thai dried mandibles as potential surgical landmarks for vertical ramus osteotomy

This study aims to investigate positions of the antilingula (AL), the midwaist of the mandibular ramus (MW) and the midpoint between the coronoid process and the gonion (MCG) in relation to the lingula of dried mandibles. Bilateral rami of 92 Thai dried mandibles were studied. The AL, the MW, the MCG and the corresponding position of the tip of lingula (L) were marked on the external aspect of the mandibular ramus. The distances from the AL, the MW and the MCG to the L were measured in the anterior-posterior and the superior-inferior planes using computerized image analysis. The results showed the AL was discernible in 80.4% of lateral mandibular rami studied. The most of the AL was found anterior-superior to the L with a maximum distance of 5.9 mm anteriorly and 8.2 mm superiorly. The MW was frequently located anterior-inferior to the L with a maximum distance of 9.3 mm anteriorly and 9.9 mm inferiorly. The majority of the MCG was found anterior-superior to the L with a maximum distance of 9.6 mm anteriorly and 8.9 mm superiorly. A 5 mm radius from the L included 84.5% of the AL, 81.5% of the MW and 79.4% of the MCG. Medians (interquartiles) of distances from the AL, the MW and the MCG to the L were 3.4 (2.3-5.0) mm, 3.8 (2.5-5.3) mm and 4.1 (2.8-5.3) mm, respectively. In conclusion, the AL was identified in 80.4% of lateral mandibular rami studied. The AL and the MCG were commonly found anterior-superior to the lingula, whereas the MW was mostly observed anterior-inferior to the lingula. Therefore, a cut made more than a 5 mm posterior or superior to these landmarks would be in 79% of cases, within a statistically safe area avoiding encroaching upon the inferior alveolar neurovascular bundle passing immediately lateral to the lingula. Although the MW and the MCG might be alternative surgical guides when the AL is absent, their use alone as surgical landmarks is not recommended.

Condylar luxation following bilateral intraoral vertical ramus osteotomy

OBJECTIVE

The intraoral vertical ramus osteotomy (IVRO) is widely used to treat mandibular prognathism and some forms of temporomandibular joint disorder (TMD). This retrospective report evaluated the incidence of condylar luxation following bilateral IVRO.

STUDY DESIGN

Clinical records and radiographs of 319 patients seen during a 13-year period between 1992 and 2005 were evaluated. The mean age of the patients (232 females, 87 males) at the time of surgical procedure was 26.1 years. All patients underwent a bilateral IVRO to treat mandibular prognathism or TMD. Postoperatively, the condylar position was evaluated from lateral and anteroposterior cephalograms and tomograms of the temporomandibular joint (TMJ).

RESULTS

An IVRO was performed on 638 sides in 319 patients. In 8 sides in 8 patients, the proximal segments were dislocated, and the condylar heads were located beyond the articular eminence. One patient underwent a closed reduction under local anesthesia, and 4 patients underwent an open reduction under sedation or general anesthesia. The average follow-up period was 4.3 years (1.2-9 years). Six of the 8 patients did not complain of any TMJ dysfunction. The objective clinical evaluation also did not reveal any dysfunctional patterns. A TMJ click on the affected side was observed in 1 patient, and mandibular deviation to the affected side upon opening the mouth was observed in 1 patient.

CONCLUSION

Although condylar sag is a consistent finding after IVRO, the mandibular condyles tend to return their preoperative positions. In this study, condylar luxation was observed in 1.3% (8/638) of the joints after bilateral IVRO. However, there were no severe clinical problems in these patients during a relatively long follow-up period.