Treating Temporomandibular Disorders Through Orthodontics: A Scoping Review of Evidence, Gaps, and Clinical Guidance

Does Orthognathic Surgery Cause or Cure Temporomandibular Disorders? A Systematic Review and Meta-Analysis

Objective: Maxillofacial Orthognathic surgery is performed to repair or correct the skeletal anomalies of the jaw and its associated dental and facial structures. There is a conflict on whether orthognathic surgery has a negative or positive effect on temporomandibular disorders (TMD). The aim of this study is to review the disorders of the temporomandibular joint after orthognathic surgery. Materials and Methods: Data for this review was obtained from the articles published be- tween 2010-2020 via PubMed, Google scholar, Web of Sciences, and Scopus engines. The content keywords matched those used in PubMed and Mesh engines. Based on the inclusion and exclusion criteria; 27 articles were included. Results: Most of the selected articles were retrospective reviews and performed on class II and class III patients. Ages ranged from 19- 47 years. Pain reduction was reported in 11 studies, while 8 studies reported a click reduction post orthognathic operation. In 2 studies, decreased joint noises was reported after orthognathic operation, and 7 articles reported a decrease in maximum mouth opening. Three studies reported a Bilateral Sagittal split Osteotomy (BSSO) and in one study, re- duced and improved symptoms after Le Fort I + (BSSO) were reported. One study exhibited that BSSO orthognathic surgery is less predictable in reducing TMD symptoms in retrognathic patients. Three articles showed that orthognathic patients with TMJ click have a high predictive value. Conclusion: To accomplish accurate results regarding temporomandibular joint disorders post orthognathic surgery; a larger number of subjects and clinical trial studies are required, as well as extended long term follow-up.

This study aimed to explore the quantitative and qualitative condylar changes following stabilization splint (S.S) therapy, including condylar position, morphology, and bone mineral density (BMD) in subjects with temporomandibular disorders (TMD). In this retrospective clinical study, we enrolled 40 TMD subjects (80 joints) aged 18 to 35years, for whom a S.S was used to treat TMD. The 80 TMD consists of 32 masticatory muscle disorders (myalgia) and 48 TMJ disorders (arthralgia). Cone beam computed tomography (CBCT) was used to scan the TMJs of subjects pre- and post-treatment for three-dimensional analysis (3D). Using Mimics software v.21.0, quantitative (3D condylar and joint spaces dimensions parameters were measured using linear measurements in millimeters, according to the Kamelchuk method and Ikeda method, while the assessment of anteroposterior condyle position within the glenoid fossa was based on the method of Pullinger and Hollender), and qualitative (a round bone tissue with an area of 2 mm2 in three representative areas according to the Kamelchuk method to measure condylar BMD) pre- and post-treatment. Intra- and inter-group statistical comparisons were performed using the Wilcoxon signed ranks and the Kruskal-Wallis test, respectively. The course of treatment was 6-12months, with an average of 9.1months. For the pre- and post-treatment quantitative comparisons, there was a statistically significant difference in the anterior joint space (AJS) and coronal medial space, as well as the condyle length in the myalgia group and condylar width in the arthralgia group. For qualitative measurements, a significant difference was observed in the posterior slope of the myalgia group and the arthralgia group's anterior, superior, and posterior slopes. The inter-group comparisons revealed significant differences in AJS, condylar length, and anterior slope density. In short-term follow-up, the S.S influenced patients with TMD from different origins; it changes anterior and coronal medial joint space, condyle length in myalgia, and width in arthralgia. Furthermore, it improved the condyle bone density more evidently in arthralgia. This study highlights the influence of S.S on symptomatic populations with TMD of different origins from a qualitative and quantitative perspective.

Changes in condylar position after orthognathic surgery and its correlation with temporomandibular symptoms (TMD)- a prospective study

Reply: Simultaneous Midface Advancement and Orthognathic Surgery: A Powerful Technique for Managing Midface Hypoplasia and Malocclusion.

Temporomandibular disorders

Temporomandibular disorders (TMDs) are characterized by numerous pain manifestations. Their treatment often involves the use of an oral splint. Recent research has found a relationship between migraines, nociceptive pain and TMDs. The aim of the present study was to perform a scoping review of studies in order to evaluate the effectiveness of the various types of oral splint in the treatment of migraine or nociceptive pain. Publications were retrieved from seven databases (PubMed, Web of Science, EMBASE, Scopus, ProQuest, SpringerLink and Ovid). Out of the 15 included publications, three studies were before and after studies, with no control group, whereas the other twelve studies were clinical trials, among which two publications were crossover studies. A clear, single distinction of pain was difficult to describe. Therefore, numerous publications focused on a combination of various types of pains, including myofascial, temporomandibular joint, headaches and migraine-like symptoms, all of which mimicked TMD pain. Overall, six studies used the stabilization splint (SS), three explored the comparison between the SS and the nociceptive trigeminal inhibition splint (NTIS) and two the NTIS. The majority of publications reported a positive outcome of splint therapy. Regarding the type of oral splint usage, the most commonly used one was the SS, followed by the NTIS. The definition and assessment of pain were heterogenous in the identified articles. The findings of the current study showed that occlusal splints may help with pain management, and that effective treatment of TMD-related pain at an early stage can enhance the quality of life of patients.

BackgroundPsychological discomfort, physical disability and functional limitations of the orofacial system have a major impact on everyday life of patients with temporomandibular disorders (TMDs). In this study we sought to determine short and long term effects of stabilization splint (SS) in treatment of TMDs, and to identify factors influencing its efficacy.MethodsMEDLINE, Web of Science and EMBASE were searched for randomized controlled trials (RCTs) comparing SS to: non-occluding splint, occlusal oral appliances, physiotherapy, behavioral therapy, counseling and no treatment. Random effects method was used to summarize outcomes. The effect estimates were expressed as odds ratio (OR) or standardized mean difference (SMD) with 95% confidence interval. Subgroup analyses were carried out according to the use of Research Diagnostic Criteria (RDC/TMD) and TMDs origin. Strength of evidence was assessed by GRADE. Meta-regression was applied.ResultsThirty three eligible RCTs were included in meta-analysis. In short term, SS presented positive overall effect on pain reduction (OR 2.08; p = 0.01) and pain intensity (SMD -0.33; p = 0.02). Subgroup analyses confirmed SS effect in studies used RDC/TMD and revealed its effect in patients with TMDs of muscular origin. Important decrease of muscle tenderness (OR 1.97; p = 0.03) and improvement of mouth opening (SMD -0.30; p = 0.04) were found. SS in comparison to oral appliances showed no difference (OR 0.74; p = 0.24). Meta-regression identified continuous use of SS during the day as a factor influencing efficacy (p = 0.01). Long term results showed no difference in observed outcomes between groups. Low quality of evidence was found for primary outcomes.ConclusionSS presented short term benefit for patients with TMDs. In long term follow up, the effect is equalized with other therapeutic modalities. Further studies based on appropriate use of standardized criteria for patient recruitment and outcomes under assessment are needed to better define SS effect persistence in long term.

Introduction: Laterognathia is characterized by the mandibular deviation to one of the sides affected which often caused by unilateral overgrowth of the mandible and age-related adaptive remodeling changes in the temporomandibular joint (TMJ) that affected masticatory function and aesthetics. The aim of this serial case report is to discuss the surgical management for laterognathia with bilateral sagittal split osteotomy (BSSO) on a clinical case of asymmetrical dentofacial deformity due to an excessive mandibular unilateral laterognathia. Case Report: This case report contains two cases of mandibular laterognathia. Both of our patients underwent a corrective procedure with bilateral sagittal split ramus osteotomy (BSSO) that performed mandibular setback and rotation. Post-operative follow-up showed the patient was in good condition and no complications were noted. Conclusion: The mandibular setback and rotation procedure can be performed with a bilateral sagittal split ramus osteotomy (BSSO). Significant improvement of laterognathia in occlusion, masticatory function, and facial appearance was achieved by surgical management with BSSO procedure. Keywords: laterognathia, bilateral sagittal split osteotomy, mandibular setback.

BACKGROUNDWe aimed to evaluate the possibility of temporomandibular joint (TMJ) dysfunction following mandibular advancement surgery in skeletal class 2 patients. Methods:All healthy non-syndromic patients with Class 2 deformity, who were eligible for mandibular advancement surgery, were included in this before-after quasi-experimental study. The main intervention was mandibular advancement through bilateral sagittal split osteotomy (BSSO). Maxillary impaction or setback surgery using LeFort 1 osteotomy was simultaneously performed in some cases. Variables such as TMJ pain, clicking, crepitus, or any other type of sounds or complaint as well as the amount of maximum mouth opening (MMO) were evaluated before surgery and two months postoperatively. Results:Thirty patients including 15 men and 15 women with a mean age of 23.3 ±2.7 yr were studied. The mean amount of mandibular advancement displacement was 3.30 ± 0.87 mm. The rate of TMJ dysfunctions and complaints was relatively low two months postoperatively when compared to the preoperative state. Postoperative evaluation demonstrated that there was no significant correlation between the presence of TMJ symptoms and dysfunctions and the type of surgery. After treatment was completed, the mean MMO reduced significantly from 39.03±5.86 to 38.12±6.05 (P<0.001). Conclusion:Mandibular advancement with BSSO surgery in skeletal class 2 patients did not clinically lead to TMJ dysfunctions. Among all the investigated factors, only preoperative pain, noises, or complaints were proven to have predictive value for postoperative TMJ dysfunction.

Mandibular deformities negatively affect the daily activities of the patients and may cause temporomandibular disorders (TMD). Bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I osteotomy are effective treatments to correct the mandibular deformities. The aim of this study was to investigate and compare the effects of the BSSRO with or without Le Fort I on the stress distributions of the temporomandibular joints (TMJs) of the patients with mandibular deformities under centric occlusion based on finite element (FE) method. Preoperative and postoperative cone-beam computed tomography (CBCT) images of twenty-four patients diagnosed with mandibular prognathism, including ten patients with BSSRO and another 14 patients with bimaxillary osteotomy (BSSRO with Le Fort I), were used to construct maxillofacial models. Ten asymptomatic individuals were also performed CBCT scanning and defined as the control group. In addition, the muscle forces and boundary conditions corresponding to centric occlusions were applied on each model. For the preoperative groups with both the BSSRO and bimaxillary osteotomies, the average peak contact stresses of the TMJs were both greater than those of the control group. After the surgeries, the contact stresses of the discs and temporal bones of both groups considerably decreased. However, the contact stresses on the condyles slightly increased after BSSRO but decreased after bimaxillary osteotomy. The TMJs of the patients with maxillofacial deformities suffered abnormal tensile and compressive stresses compared with the asymptomatic subjects under centric occlusion. Both of the BSSRO and bimaxillary osteotomy could improve the risk stress distributions of the TMJs.

Bodybuilding and cross-training exercises bring health benefits. However, orofacial injuries can occur during practice. This study aimed to map, analyze, interpret, and synthesize data from studies on the main orofacial injuries resulting from bodybuilding and cross-training practices. This scoping review followed the Joanna Briggs Institute and PRISMA-ScR methods, with high-sensitivity searches in PubMed, Web of Science, Scopus, ScienceDirect, Embase, Virtual Health Library and the Google Scholar. Original scientific articles published up to May 2024 were included, which evaluated the presence of self-reported or professionally diagnosed orofacial injuries by bodybuilding and cross-training practitioners aged 18 years or older. Literature reviews, editorials, and guidelines were excluded. Tables and figures were used to map and summarize the results. Out of 30.485 potentially eligible articles, four were included. The main orofacial injuries identified in both bodybuilding and cross-training practitioners were dental damage (n = 4), temporomandibular joint (TMJ) disorders (n = 3), and traumas to oral soft tissues (n = 2) and facial soft tissues (n = 2). Dental damage and TMJ disorders were the most prevalent conditions among bodybuilding and cross-training practitioners. Therefore, dental damage and TMJ disorders were the most prevalent conditions among bodybuilding and cross-training practitioners. However, further prospective studies with more in-depth methodological designs and fewer biases are necessary.

Aim and Objectives: The study was designed to evaluate the temporomandibular joint disorders among dental students at the University of Science and Technology (UST). Subjects and Methods: The sample size included 267 dental students in UST aged between 18 and 27 years. The study was based on Fonseca's anamnestic index and its questionnaire, which was composed of 10 questions and an examination sheet composed of demographic data and clinical examination. Results: Of 267 students, 178 of them were female (66.7%) and 89 of them were male (33.3%). 52.1% of the study participants were with no temporomandibular disorders (TMDs), 37.5% with mild TMDs, 9.7% with moderate TMDs, and 0.7% with severe TMDs. Regarding clinical examination findings, 81.7% of the study participants were with normal mouth opening and 18.3% were with limited mouth opening. The participants with or without tenderness during palpation were 13.1% and 86.9%, respectively. Positive participants with auscultation (clicking) were 45.3% and 54.7% were negative participants. Conclusion: The mild TMDs were most common, then moderate TMDs were less common, and severe TMDs were rarely. The females were more affected. History of the past dental treatment and psychological stress was found in students having TMDs.

The Effect of Orthognathic Surgery on Temporomandibular Joint Function and Symptoms: What are the Risk Factors? A Longitudinal Analysis of 375 Patients

Short- and Long-Term Changes of Condylar Position After Bilateral Sagittal Split Ramus Osteotomy for Mandibular Advancement in Combination With Le Fort I Osteotomy Evaluated by Cone-Beam Computed Tomography