Are condylar morphologic changes associated with temporomandibular disorders in patients with orthognathia?

Changes of Temporomandibular Joint Morphology and Symptoms in Class II Malocclusion Patients With Bilateral Sagittal Split Ramous Osteotomy

This study included 46 patients with class II malocclusion ranging in age from 19 to 39 years old treated with bilateral sagittal split ramous osteotomy (BSSRO). Left and right temporomandibular joints (TMJs) of each subject were evaluated independently with cone-beam computed tomography (CBCT) before operation (T1), 1 week after operation (T2), and 1 year after operation (T3) and assessed the effects of orthognathic surgery (OGS) on the temporomandibular joint disease (TMD) symptoms. Temporomandibular joint morphology evaluation included condylar volume, condylar area, cortical bone thickness, depth of the mandibular fossa, fossa thickness, joint nodule angle, joint space, and condyle-fossa relationship, which were calculated by using the Mimics software and 3-matic software. Data were statistically analyzed with SPSS software (P <0.05 means statistically significant). In our study, bilateral TMJs have no difference in T3. Bilateral sagittal split ramous osteotomy had no significant effect on the articular fossa. The condyle volume and surface area decreased from T1 to T3, but the cortical thickness of the bone did not change significantly. More anterior condyle positions in T1 and more posterior in T3.21 patients had at least 1 sign or symptom of TMD in T1 and 27 patients in T3. Four patients who were asymptomatic in T1 developed pain after surgery, 10 developed noises, 12 showed limited mouth opening, and 8 had abnormal opening patterns. It is concluded that more condylar posterior position after BSSRO and the reduction of condyle may be related to the enlargement of anterior space. The number of patients with joint symptoms increased postoperative, and the impact of BSSRO on TMD may be negative.

Prevalence of signs and symptoms related to temporomandibular disorders and orofacial pain in patients indicated for orthognathic surgery: a meta-analysis

OBJECTIVE

To evaluate the prevalence of signs and symptoms related to temporomandibular disorders (TMD) and orofacial pain in patients with indication for orthognathic surgery.

METHODS

The search was carried out in seven electronic databases and gray literature. Studies that evaluated the frequency of signs and symptoms related to TMD and orofacial pain were included. The risk of bias was assessed using the Joanna Briggs Critical Appraisal tool. A meta-analysis of proportions with a random effect model was performed and the GRADE tool judged the certainty of evidence.

RESULTS

After searching the databases, 1859 references were retrieved, 18 of which were selected for synthesis. The prevalence of individuals with at least one TMD symptom was 51% [CI95% = 44-58%], and 44% of the subjects had temporomandibular joint click/crepitus [CI95% = 37-52%]. Additionally, 28% exhibited symptoms related to muscle disorders [CI95% = 22-35%], 34% had disc displacement with or without reduction [CI95% = 25-44%], and 24% had inflammatory joint disorders [CI95% = 13-36%]. The prevalence of headache was 26% [CI95% = 8-51%]. The certainty of evidence was considered very low.

CONCLUSION

Approximately 1 in 2 patients with dentofacial deformity presents some sign and symptom related to TMD. Myofascial pain and headache may be present in approximately a quarter of patients with dentofacial deformity.

CLINICAL RELEVANCE

A multidisciplinary treatment is necessary for these patients, involving a professional with expertise in the management of TMD.

Condylar resorption following mandibular advancement or bimaxillary osteotomies: A systematic review of systematic reviews

Several systematic reviews have been published on the effects of mandibular surgery on condylar remodeling without reaching a consensus. The purpose of this systematic review of systematic reviews was to assess the impact of mandibular advancement or bimaxillary surgeries on condylar resorption. A literature search, using several electronic databases, was carried out by two reviewers independently. Article preselection was based on titles and abstracts, and final article selection based on full-text analysis of preselected studies. After final study selection, the quality of studies was assessed using the AMSTAR 2 tool. A decision algorithm was subsequently established to choose the best body of evidence. From an initial yield of 1'848 articles, 23 systematic reviews were identified for further analysis, with ten studies being included in the final selection. Despite the generally low quality of the reviews, certain associations could be made: young patients, female patients, and those with a high mandibular plane angle are more prone to condylar resorption following mandibular advancement osteotomies, especially if anterior rotation of the mandible is performed during surgery. Patients undergoing bimaxillary surgery also appear to have a higher risk of developing condylar resorption. In conclusion, these results confirm the multi-factorial nature of condylar resorption, stressing the need for well-controlled prospective studies with long-term follow-up to clearly identify potential risk factors associated with orthognathic surgery.

Bilateral temporomandibular joint ankyloses after bilateral sagittal split osteotomy of the mandible: An uncommon clinical case with long-term outcome evaluation

Temporomandibular joint (TMJ) ankylosis is an extremely handicapping condition characterized by a permanent restriction in the ability to open the mouth, and it is mainly caused by traumatic and infectious events. It rarely occurs as a complication following orthognathic surgery. The treatment goals are the restoration of viable mandibular function and, in growing pediatric patients, symmetrical mandibular development. We are reporting here the unusual case of a bilateral bony TMJ ankylosis in a patient who underwent a bilateral sagittal split osteotomy of the mandible for correction of a mandibular deficiency. The patient was treated by bilateral arthrotomies with the interposition of a full-thickness skin graft as well as bilateral coronoidectomies with a favorable long-term (6 years) functional outcome. Only one similar case has been previously reported in the literature.

[Orthognathic surgery: the incisor decompensation and its effect on articulation]

INTRODUCTION

The surgical protocols are based on arches preparation before or immediately after the surgical phase. Incisor guides normalization is achieved by incisor decompensation in three dimensions. Place and extend of surgical movements depend on the incisor position obtained at the end of orthodontic preparation. Extraction versus non extraction depends on incisor position planning. Orthognathic surgery induces muscular and temporo-mandibular joint stress which can cause temporo mandibular dysfunction (TMD).

OBJECTIVES

This article studies relations between incisor decompensation amplitude, orthognathic surgical procedures and risk to create or to increase TMD.

CONCLUSIONS

Sagittal, vertical and transversal incisor decompensation impact to place and amplitude of surgical movements. Incisor decompensation does not seem to induce TMD during orthodontic preparation even if occlusal guide controls are lost. Temporo mandibular dysfunction degrees define surgical movements area, moderate specially mandibular surgical movements and incisor decompensation objectives.