OBJECTIVES: This study aimed to investigate the association between temporomandibular disorder (TMD) and insomnia using a two-sample Mendelian randomization (MR) approach. METHODS: Bidirectional MR analyses of two samples, TMD (n=377 277) and insomnia (n=375 359), were performed using genome-wide association study statistics published in the FinnGen database. Instrumental variables were first screened, and then inverse variance weighting (IVW) and MR-Egger were used as the main-effect assessment methods. Weighted median, weighted mode, and simple mode served as supplementary methods. We used IVW and MR-Egger to test for heterogeneity, as well as MR-Egger intercepts to assess the single nucleotide polymorphism (SNP) potential level of multiplicity effects. Sensitivity analyses were conducted based on leave-one-out to identify potentially influential SNPs. All analyses were conducted by using the two-sample MR R package and were considered statistically significant when P<0.05. RESULTS: MR analysis showed the presence of TMD on insomnia (OR=1.089, 95%CI: 1.017-1.166, P=0.014). Meanwhile, no effect of insomnia on TMD (OR=0.996, 95%CI: 0.964-1.029, P=0.816) was found. The sensitivity-analysis showed that no heterogeneity existed (P>0.05), and the presence of horizontal pleiotropy was not detected (P>0.05). Leave-one-out sensitivity analysis showed no single SNP, which may affect the causal relation. All findings indicated that the causal relationship between TMD and insomnia was not significantly affected by any individual SNP and that IV did not bias the results. CONCLUSIONS Results of MR analyses showed that TMD is a risk factor for insomnia, whereas insomnia is not a risk factor for TMD.
Humans ; Sleep Initiation and Maintenance Disorders/genetics* ; Mendelian Randomization Analysis ; Polymorphism, Single Nucleotide ; Temporomandibular Joint Disorders/complications* ; Genome-Wide Association Study

Humans ; Temporomandibular Joint/diagnostic imaging* ; Temporomandibular Joint Disorders/complications* ; Calcinosis/diagnostic imaging*

PURPOSE: Various complications occur when a maxillofacial fracture is malunionized or improperly resolved. Malocclusion is the most common complication, followed by facial deformity, temporomandibular joint disorder (TMD), and neurological symptoms. The purpose of this study was to evaluate the dental treatment of postoperative complications after maxillofacial fracture. MATERIALS AND METHODS: In this study, nine patients with a postoperative complication after maxillofacial fracture who had been performed the initial operation from other units and were referred to the authors’ department had been included. Of the nine patients, six had mandibular fractures, one had maxillary fractures, one had maxillary and mandibular complex fractures, and one had multiple facial fractures. All the patients had tooth fractures, dislocations, displacements, and alveolar bone fractures at the time of trauma, but complications occurred because none of the patients underwent preoperative and postoperative dental treatment. Malocclusion and TMD are the most common complications, followed by dental problems (pulp necrosis, tooth extrusion, osteomyelitis, etc.) due to improper treatment of teeth and alveolar bone injuries. The patients were referred to the department of dentistry to undergo treatment for the complications. One of the nine patients underwent orthognathic surgery for a severe open bite. Another patient underwent bone reconstruction using an iliac bone graft and vestibuloplasty with extensive bone loss. The other patients, who complained of moderate occlusal abnormalities and TMDs such as mouth-opening limitation, underwent occlusal treatment by prosthodontic repair and temporomandibular joint treatment instead of surgery. RESULTS: One patient who underwent orthognathic surgery had complete loss of open bite and TMD after surgery. One patient who underwent reconstruction using an iliac bone graft had a good healing process. Other patients were treated with splint, injection, and physical therapy for mouth-opening limitation and temporomandibular joint pain. After treatment, the TMDs were resolved, but the remaining occlusal abnormalities were resolved with prosthetic restoration. CONCLUSIONS: Considering the severity of malocclusion and TMJ symptom and the feasibillity of reoperation, nonsurgical methods such as orthodontic and prosthodontic treatments and splint therapy can be used to manage the dental and TMD complication after the trauma surgery. However, reoperation needs to be strongly considered for severe malocclusion and TMD problem. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40902-018-0167-z) contains supplementary material, which is available to authorized users.
Congenital Abnormalities ; Dentistry ; Dislocations ; Fractures, Bone ; Humans ; Malocclusion ; Mandibular Fractures ; Maxillary Fractures ; Necrosis ; Open Bite ; Orthodontic Extrusion ; Orthognathic Surgery ; Osteomyelitis ; Postoperative Complications ; Reoperation ; Retrospective Studies ; Splints ; Temporomandibular Joint ; Temporomandibular Joint Disorders ; Tooth ; Tooth Fractures ; Transplants ; Vestibuloplasty

OBJECTIVES: The aim of this study was to evaluate the implication of third molars in postoperative complications of mandibular angle fracture with open reduction and internal fixation (ORIF). MATERIALS AND METHODS: Data were collected on patients who presented with mandibular angle fracture at our Department of Oral and Maxillofacial Surgery between January 2011 and December 2015. Of the 63 total patients who underwent ORIF and perioperative intermaxillary fixation (IMF) with an arch bar, 49 patients were identified as having third molars in the fracture line and were followed up with until plate removal. The complications of postoperative infection, postoperative nerve injury, bone healing, and changes in occlusion and temporomandibular joint were evaluated and analyzed using statistical methods. RESULTS: In total, 49 patients had third molars in the fracture line and underwent ORIF surgery and perioperative IMF with an arch bar. The third molar in the fracture line was retained during ORIF in 39 patients. Several patients complained of nerve injury, temporomandibular disorder (TMD), change of occlusion, and postoperative infection around the retained third molar. The third molars were removed during ORIF surgery in 10 patients. Some of these patients complained of nerve injury, but no other complications, such as TMD, change in occlusion, or postoperative infection, were observed. There was no delayed union or nonunion in either of the groups. No statistically significant difference was found between the non-extraction group and the retained teeth group regarding complications after ORIF. CONCLUSION: If the third molar is partially impacted or completely nonfunctional, likely to be involved in pathologic conditions later in life, or possible to remove with the plate simultaneously, extraction of the third molar in the fracture line should be considered during ORIF surgery of the mandible angle fracture.
Humans ; Mandible ; Mandibular Fractures ; Molar, Third* ; Postoperative Complications* ; Surgery, Oral ; Temporomandibular Joint ; Temporomandibular Joint Disorders ; Tooth

This article summarized the advances in treatment and research of temporomandibular joint surgery in the last 5 years which was presented in "The 2nd Condyle Fracture and Temporomandibular Joint Ankylosis Symposium". The content includes 5 parts: non-surgical treatment of children condyle fracture and long-term follow-up, the improvement of operative approach for condyle fracture and key techniques, the importance and the method for the simultanesous reduction of disc in condylar fracture treatment, the development of traumatic temporomandibular joint ankylosis similar to hypertrophic non-union and the improved safety and accuracy by applying digital surgery in joint surgery.
Ankylosis ; etiology ; Humans ; Mandibular Condyle ; injuries ; Mandibular Fractures ; complications ; therapy ; Temporomandibular Joint ; surgery ; Temporomandibular Joint Disorders ; etiology

OBJECTIVES: The aim of this study is to report the results of extracorporeal fixation in patients with mandibular condylar fractures and compare them with the clinical results of conservative treatment. MATERIALS AND METHODS: The medical records of 92 patients (73 male [M] : 19 female [F], age 13-69 years, mean 33.1 years) treated for condylar fractures at the Department of Oral and Maxillofacial Surgery in Sun Dental Hospital (Daejeon, Korea) from 2007 to 2012 were reviewed. Patients were divided into three groups: group A (23 patients; M : F=18 : 5, age 21-69 years, mean 32.6 years), treated with extracorporeal fixation; group B (30 patients; M : F=24 : 6, age 16-57 years, mean 21.1 years), treated by conventional open reduction; and group C (39 patients; M : F=31 : 8, age 16-63 years, mean 34.4 years), treated with the conservative method ('closed' reduction). Clinical and radiographic findings were evaluated and analyzed statistically. RESULTS: Occurrence of postoperative condylar resorption correlated with certain locations and types of fracture. In this study, patients in group A (treated with extracorporeal fixation) did not demonstrate significant postoperative complications such as malocclusion, mandibular hypomobility, temporomandibular disorder, or complete resorption of condyle fragments. CONCLUSION: In superiorly located mandibular condyle fractures, exact reconstruction of condylar structure with the conventional open reduction technique can be difficult due to the limited surgical and visual fields. In such cases, extracorporeal fixation of the condyle using vertical ramus osteotomy may be a better choice of treatment because it results in anatomically accurate reconstruction and low risk of complications.
Female ; Follow-Up Studies* ; Humans ; Male ; Malocclusion ; Mandibular Condyle ; Mandibular Fractures ; Medical Records ; Osteotomy* ; Postoperative Complications ; Solar System ; Surgery, Oral ; Temporomandibular Joint Disorders ; Visual Fields

Animals ; Estrogens ; metabolism ; Gene Expression Regulation ; Humans ; Osteoarthritis ; complications ; genetics ; metabolism ; Pain ; etiology ; Pain Measurement ; Temporomandibular Joint ; pathology ; Temporomandibular Joint Disorders ; complications ; genetics ; metabolism ; Wnt Signaling Pathway

OBJECTIVETo study the prevalence of temporomandibular disorders (TMD) in 352 aged edentulous individuals in Beijing area and to analyze the correlative risk factors.

METHODSThree hundred and fifty-two aged edentulous subjects were included in the study (198 males and 154 females). The adopted questionnaire was designed according to Helkimo index, and the subjects were examined by the same examiner who would record every result as well.

RESULTSThe prevalence of TMD's clinical positive signs in the edentulous subjects was 43.2% (152/352), among which temporomandibular joint (TMJ) noise [34.1% (120/352)] was the highest prevalent sign while TMJ pain on movemert was the lowest. The prevalence of mandibular movement deviation [18.2% (64/352)] fitted in between. The prevalence of TMD's clinical positive signs of male individuals was 36.9% (73/198), and the female was 51.3% (79/154). There was a significant difference in prevalence of TMD's clinical positive signs between males and females (P = 0.0067 < 0.01). The prevalence of TMD's clinical positive signs in denture wearing group was 38.6% (91/236) and that in no denture group was 52.6% (61/116). There was a significant correlation between the prevalence of TMD's clinical positive signs and wearing denture [P = 0.0125 < 0.05, OR = 1.767 (1.130 ∼ 2.763)].

CONCLUSIONSGender and malocclusion may be the risk factors of TMD in edentulous individuals.

Aged ; Aged, 80 and over ; Dentures ; Female ; Humans ; Jaw, Edentulous ; complications ; Male ; Malocclusion ; complications ; Middle Aged ; Risk Factors ; Sex Factors ; Temporomandibular Joint Disorders ; complications

OBJECTIVETo analyze the relationship between Class III malocclusion and pathological changes in temporomandibular joint (TMJ) structures using magnetic resenonce imaging (MRI).

METHODSTwenty-four Class III malocclusion adult patients and 10 normal control cases were included in the study. The characteristics of lateral pertygoid muscle (LPM) in the sample group and the control group were assessed.

RESULTSMore pathological changes of LPM were found in Class III malocclusion adult patients (36 TMJ). The changes included hypertrophy, atrophy and contracture. And there was no relation between the pathological changes of LPM and the symptom of temporomandibular disorders (TMD).

CONCLUSIONSThe frequency of pathological changes of LPM was greater in patients with Class III malocclusion than in the control group.

Adolescent ; Adult ; Atrophy ; pathology ; Case-Control Studies ; Contracture ; pathology ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Malocclusion, Angle Class III ; complications ; pathology ; Pterygoid Muscles ; pathology ; Temporomandibular Joint ; pathology ; Temporomandibular Joint Disorders ; complications ; pathology ; Young Adult

This study was to describe the use of inverted-L osteotomy of ramus and iliac bone graft for the management of mandibular deficiency in adult patients. From 2008 to 2010, 11 patients (aged 19 to 29 years) with mandibular deficiency underwent intraoral or extraoral inverted-L osteotomy of ramus and iliac crest bone grafting. Data were collected from the patients' records, photographs and radiographs. The height and width of the ramus were successfully expanded by inverted-L osteotomy and iliac crest bone grafting with minimal complications in all patients, resulting in significant improvement in occlusion and facial appearance. Our early results showed that the inverted-L osteotomy of ramus and iliac crest bone grafting is safe and effective, and should be considered as a good alternative for the patients with mandibular deficiency.
Adolescent ; Adult ; Ankylosis ; surgery ; Bone Plates ; Bone Transplantation ; methods ; Branchial Region ; abnormalities ; Facial Asymmetry ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Mandibular Diseases ; surgery ; Mandibular Injuries ; surgery ; Mandibular Osteotomy ; methods ; Photography ; Postoperative Complications ; Retrospective Studies ; Temporomandibular Joint Disorders ; surgery ; Treatment Outcome ; Young Adult