Temporomandibular Joint Lesions Research Articles

A Novel Technique for Resection and Reconstruction of the Temporomandibular Joint by Sliding Vertical Ramus Osteotomy using Only Submandibular Approach.

In this paper, an innovative technique for resection and reconstruction of the temporomandibular joint by sliding vertical ramus osteotomy using only a submandibular approach is presented. Before pulling the posterior mandibular border slightly downward to expose parts of the condyle, the vertical ramus osteotomy was performed. With the help of 3D simulation and surgical templates, the condylectomy was carried out using the ultrasonic osteotome through the submandibular approach. Our technique achieved the desired results while preventing complications of facial nerve paralysis, the occurrence of Frey syndrome, and the preauricular scar. Therefore, we suggest that this surgical method represents an alternative treatment option for temporomandibular joint lesions.

Effects of mandibular distraction osteogenesis on anesthetic implications in children with hemifacial microsomia.

Hemifacial microsomia (HFM) is a congenital craniofacial malformation, and its features include hypoplasia and asymmetry in skeletal tissue and soft tissue. These features are usually associated with a difficult airway. Mandibular distraction osteogenesis can achieve mandibular advancement, but its effect on the subsequent laryngoscopic views has not been adequately documented. The aim of this study was to determine the change in laryngoscopic views after mandibular distraction osteogenesis (MDO) in children with HFM and to examine the radiological changes after MDO by using computed tomography (CT)-based three-dimensional (3-D) airway reconstruction. An observational prospective study was carried out in children with HFM undergoing MDO. All children underwent 3-D airway reconstruction preoperatively before the placement and removal of the distractor. The temporomandibular joint lesions in children were classified by the Pruzansky-Kaban classification. The Cormack-Lehane grade was assessed after induction under direct laryngoscopy. The relationship between difficult laryngoscopy and the Pruzansky-Kaban classification was assessed. Changes in the upper pharyngeal airway parameters and laryngoscopic views were analyzed. Forty children (ages ranging from 5 to 16 years, males=26, females=14) with HFM underwent 80 anesthesia for MDO. The incidence of difficult laryngoscopy before mandibular distraction was 5/12 (41.7%) in type IIa, 19/24 (79.2%) in type IIb and 1/4 (25%) in type III HFM. The mean difference in the incidence of difficult laryngoscopy before and after MDO was 33.3% (95% CI: -6.7% to 73.3%), 50.0% (95% CI: 8.4% to 91.6%), and 0% for type IIa, type IIb, and type III, respectively. In type IIb, 12/19 cases of difficult laryngoscopy became easy after mandibular distraction: this was associated with an increase in the palatopharyngeal and glossopharyngeal CT parameters (p < .05). In type IIa, 5/5 cases of difficult laryngoscopy became easy after mandibular distraction, and 1/7 cases of easy laryngoscopy became difficult laryngoscopy. However, there were no significant changes in the palatopharyngeal, glossopharyngeal, and hypopharyngeal CT parameters in type IIa and type III HFM (p>.05). MDO can improve the laryngoscopic views in children with HFM. According to the Pruzansky-Kaban classification, children with type IIb showed the highest incidence of difficult laryngoscopy before MDO. After MDO, the improvement in laryngoscopic views under direct laryngoscopy in type IIb was related to the increase in the palatopharyngeal and glossopharyngeal volume.

A Case of Synovial Chondromatosis of Temporomandibular Joint with Numerous Loose Bodies

Here, we report a case of synovial chondromatosis of the temporomandibular joint (TMJ) with numerous loose bodies. A 56-year-old woman was examined in the oral surgery department for trismus and pain in the left TMJ when opening the mouth. Imaging indicated TMJ synovial chondromatosis, and the patient was referred to our department for further examination. Her facial features were symmetrical, and no occlusal abnormalities were found. The maximum mouth opening was 30 mm, and movement of the left mandibular condyle was restricted and accompanied by pain and joint sounds. Panoramic radiography showed deformation of the left mandibular condyle and radiopaque lesions surrounding it. Computed tomography showed numerous small granules around the left mandibular condyle, some of which were calcified. Magnetic resonance imaging showed anterior disc displacement without reduction in the left TMJ and hypointense lesions on T2-weighted images. Bone scintigraphy showed an accumulation in the area of the left TMJ. Based on the diagnosis of the left TMJ synovial chondromatosis, the lesions were removed, and plastic surgery on the mandibular condyle was performed under general anesthesia. We removed 386 white loose bodies. Histopathologically, the loose bodies were consistent with synovial chondromatosis lesions. The postoperative course was uneventful, with no recurrence or TMJ dysfunction approximately 5 years after the surgery, indicating that open surgery is the best course of intervention in such cases.

Mineral deposition intervention through reduction of phosphorus intake suppresses osteoarthritic lesions in temporomandibular joint

To explore the suppressing impact of low phosphorus intake on osteoarthritic temporomandibular joint and the possible mechanisms of nuclear acid injury in the insulted chondrocytes. Chondrocytes were loaded with fluid flow shear stress (FFSS) with or without low phosphorus medium. Seventy-two mice (sampled at 3-, 7- and 11-wk, n=6) and forty-eight rats (sampled at 12-wks for different testing purpose, n=6) were applied with unilateral anterior crossbite (UAC) with or without low phosphorus diet. In the FFSS model, the Ca and P content, molecules related to nucleic acid degradation and the mineral-producing responses in chondrocytes were detected. The effect of culture dish stiffness on chondrocytes osteogenic differentiation was measured. In the UAC model, the content of Ca and P in serum were tested. The condylar cartilage ossification and stiffness were detected using micro-CT, scanning electron microscope and atomic force microscope. FFSS induced nucleic acid degradation, Pi accumulation and mineral-producing responses in the cultured chondrocytes, all were alleviated by low P medium. Stiffer dish bottoms promoted the osteogenic differentiation of the cultured chondrocytes. UAC stimulated cartilage degeneration and chondrocytes nucleic acid damage, increased PARP 1 and serum P content, and enhanced ossification and stiffening of the cartilage, all were suppressed by low phosphorus diet (all, P<0.05). Nucleic acid damage takes a role in phosphorus production in osteoarthritic cartilage, contributing to the enhanced mineralization and stiffness of the cartilage that in turn promotes cartilage degradation, which can be alleviated by low phosphorus intake.

Lesions of the lateral pterygoid muscle—an overestimated reason for temporomandibular dysfunction: a 3T magnetic resonance imaging study

The aim of this study was to examine the lateral pterygoid muscle (LPM) parenchyma, myotendinous junction, and tendon in temporomandibular disorder (TMD) patients using 3T magnetic resonance imaging (MRI). Results were compared with findings reported in the literature, in which the LPM has been attributed a major role in triggering TMD. 3T MRI was used for temporomandibular joint (TMJ) imaging. The MRI images of 63 patients were analysed for muscle contracture and atrophy, tendon rupture, signal alterations of the tendon, tendon contrast enhancement, and peritendinous fluid collection. Descriptive statistics and the coefficient estimate method were used for statistical analysis. Focus was placed on the association between LPM tendon pathology and TMJ lesions like osteoarthritis and disc displacement. Severe lesions of the LPM tendon and muscle parenchyma, like rupture or fibrosis, were detected in very few cases. Only moderate signs of tendinosis were found in TMD patients. In contrast, there was a clear correlation between tendon lesions and osteoarthritis or anterior disc displacement. These results indicate the need to discuss and question the role of the LPM and its tendon in TMD. Data suggest that LPM and tendon lesions are part of complex degenerative changes of the TMJ, and it seems less likely that a LPM disorder is causative in TMD.

Characteristics of MRI and associated pathological features of the condylar cyst like lesions in temporomandibular joint

Objective: To analyze the MRI characteristics and pathological features of the condylar cyst like lesions in temporomandibular joint (TMJ). Methods: The study was conducted retrospectively on TMJ images from 14 patients (2 males, 12 females, aged 10-71) who underwent MRI examinations, from January 2015 to December 2017 at Center for TMD and Orofacial Pain, Peking University School and Hospital of Stomatology including 2 patients with pathological results. The signals of the lesion, condylar bone and disc-condyle relationship were evaluated. Results: Cyst like lesions of 15 condyles from 14 patients were analyzed. All of the lesions showed hypersignal on T2WI (12/12), while most of them showed hypersignal on T1WI (8/11) and PDWI (11/12). Mostly the lesions were surrounded by hyposignal linear margin (12/15), with normal condylar bone signal (13/15). Disk displacement with reduction was discovered in 3 joints, while disk displacement without reduction was discovered in 8 joints and 4 joints had normal disk-condyle relationships. The pathological components of cyst like lesions included cartilage, loose connective tissue, hemorrhage and bone tissue. Conclusions: Differed from those of large joints like hips or knees, MRI characteristics of cyst like lesions of condyle in TMJ exhibited hypersignal imaging in both T1WI and T2WI, indicating that the components of cyst like lesions included granulation tissue, not fluid.

Minimally Invasive Temporomandibular Joint Surgery Methods using Surgical Treatment of Hyaluronic Acid in Patients with Various Diseases

The complex approach to the treatment of patients with RD has been elaborated at the department. At the preparatory stage, the doctor rheumatologist assesses the activity of the disease and, in case of necessity, provides the adjustment of therapy in order to get the lowest activity / remission of the main disease for about ≥1 months. Temporomandibular joint (TMJ) involvement occurs in patients with different rheumatic diseases (RDs). Pain, limitation of mouth opening can lead to significant problems. Conservative treatments for TMJ lesions are not always effective. Objective: to evaluate the efficiency of minimally invasive surgical interventions (TMJ arthrocentesis and arthroscopy) in patients with RDs. Patients and methods: In case of TMJ dysfunction (the mouth opening, closure, chewing, speaking), and lateral and/or protrusion, discomfort, pain, all the degenerative changes detected on MRI need surgical treatment. 80 patients turned to our clinic center. Most of them (n = 70) were diagnosed with RD. Objective examination resulted revealed 93.8% of cases of the limitation in mouth opening and the articulation disorder. 19 patients (28.1%) had masticatory muscle hypertonicity, mostly bilateral (88,9%). In 62.9% of patients participating in the study, the damage to TMJ according to the international classification of Wilkes was attributed to stage IV, in 21.9 and 14.9% - to stage III and V, respectively. The clinical and instrumental investigations, patients with stages IV and V according to the Wilkes International Classification, underwent TMJ arthroscopy and patients with III – TMJ arthrocentesis with arthro lavage. All the patients underwent TMJ magnetic resonance imaging at baseline and 6 months after treatment. After a surgical intervention, a gel containing hyaluronic acid was used as a fluid implant. 14th day and, 1, 6,12 months after the operation, the examination of the disks in the joints showed their normal movement and normal amplitude of the condyles. Results and discussion: After surgical treatment, all the groups were noted to have a significant decrease in TMJ pain intensity compared with the baseline level; moreover, the severity of TMJ pain most significantly decreased on day 7 after surgery. Later on, positive changes remained 12 hours after the operation, the patient noted mild periodic pain of the right TMJ while the mouth opening, which was estimated by VAS scale up to 10 mm by the patient. The size of the mouth opening increased up to 35 mm.

Customized skull base–temporomandibular joint combined prosthesis with 3D-printing fabrication for craniomaxillofacial reconstruction: a preliminary study

Temporomandibular joint (TMJ) lesions, when large and extensive, will often involve skull base destruction and result in extensive resections, requiring a challenging reconstruction. This study introduces a special type of craniomaxillofacial prosthesis for massive combined skull base–TMJ lesions. Patients who presented with combined skull base–TMJ lesions were recruited. Enhanced computed tomography (CT) data were obtained for all patients and transformed into three-dimensional (3D) reconstruction models. The combined skull base–TMJ prosthesis was designed and fabricated with a customized principle by 3D-printing technology. Clinical follow-up and radiographic evaluations were performed to assess the feasibility of the combined prosthesis in clinical application. A series of five consecutive patients were included in this study. No severe complications occurred after surgery. Based on a mean follow-up period of 13.8 months, the preliminary results suggest that the combined prosthesis has a positive impact on clinical outcomes: there was a mean 75.0% reduction in pain, 55.6% improvement in diet, 54.5% improvement in mandibular function, and 33.6% increase in mouth opening, with significant differences when compared with the preoperative state (all P<0.05). This study suggests that the combined prosthesis represents a safe and reliable implantable reconstruction method for combined skull base–TMJ lesions.

A case report: A rare presentation of mandibular condylar fibrous dysplasia

Fibrous Dysplasia is a fibro-osseous lesion characterized by the progressive replacement of normal bone by fibrous connective tissue resulting from arrest of bone maturation from woven bone to lamellar bone by a missense mutation. We report a 33-year old patient who presented with inability to open her of a month duration. On examination, patient had facial assymetry, anterior and posterior crossbite but scissors bite on the contralateral side, mouth deviation to the left on mouth opening associated with limited mouth opening, and there was no apparent swelling at the right preauricular region. The patient subsequently underwent surgery under general anesthesia following computed tomography (CT) scan. Fibrous dysplasia is a rare occurrence of the mandibular condyle, and its possibility in this location should be considered, pending a histopathologic report and the clinical importance of CT scan in the evaluation of temporomandibular joint lesions should be emphasized.

Temporomandibular joint anomalies in pediatric craniofacial Gorham-Stout disease

PurposeGorham-Stout disease (GS) is a rare and little understood bone disease that leads to the progressive replacement of the affected bone by fibrous tissues. The mandible is the most commonly affected craniofacial bone, but there is no report to date of temporomandibular joint (TMJ) lesions in this condition. We aimed to characterize the involvement of the TMJ in this uncommon bone disorder. Material and methodsWe retrospectively included all patients managed for craniofacial forms of GS in our pediatric institution over a period of 12 years. We collected clinical data on TMJ function and radiological data from computed tomography and magnetic resonance imaging. ResultsFour pediatric patients were managed for craniofacial forms of GS between 2005 and 2017. All patients presented with various radiological lesions of the TMJs, including osteolytic lacunae of the condylar head, condylar head flattening and thinning of the glenoid cavity. Only one patient presented with functional TMJ impairment. ConclusionThe TMJ appears to be radiology affected in pediatric craniofacial forms of GS. Nevertheless, TMJ lesions, even when radiologically severe, rarely impair TMJ function. TMJ structure and function should be systematically assessed in craniofacial forms of GS, and, in the case of joint lesions, a regular follow-up of TMJ function should be considered.

Expansile radiolucent lesion of the Temporomandibular Joint—A diagnostic enigma

Radiolucent lesions of Temporomandibular Joint (TMJ) represent a diagnostic challenge and a treatment conundrum. Biopsy of the lesions is technically difficult owing to their complex anatomy. The Differential Diagnosis (DD) includes a wide array of lesions including Simple Bone Cyst, Ameloblastoma, Central Giant Cell Granuloma, Hemangioma, Osteoblastoma, Osteochondroma, Chondroblastoma, Chondrosarcoma, Neurofibroma and metastatic malignant lesions though none has a specific predilection for TMJ. Here we present a case report of a large expansile radiolucent lesion of right TMJ in a 22 year old male patient with difficulties involved in diagnosis and management. Though cystic lesion of TMJ is uncommon it is incumbent on the Maxillofacial Surgeon for an early diagnosis and prompt management.

Benign Temporomandibular Joint Lesions Presenting as Masses in the External Auditory Canal.

Describe benign lesions arising from the temporomandibular joint (TMJ) that presented as masses in the external auditory canal (EAC). Retrospective case series of two academic medical centers. Six patients with lesions emanating from the TMJ that presented as EAC masses. Lesions included pigmented villonodular synovitis (PVNS), nodular fasciitis, foramen of Huschke herniation with salivary fistula, fibroepithelial polyp, superficial angiomyxoma, and giant cell tumor (GCT). Surgical resection. Tumor control, TMJ function, and hearing. All patients presented with hearing loss, TMJ pain, and otalgia. Three patients with EAC occluding masses developed entrapment cholesteatoma between the mass and tympanic membrane. Following surgical resection, four patients were free of disease. The patient with PVNS has a stable remnant at 3 years follow up and the patient with giant cell tumor is under active surveillance. Hearing improved in three patients, remained stable in one patient, and worsened in two patients. All had resolution of their TMJ and ear pain. EAC masses of uncertain origin should be imaged preoperatively to exclude lesions best not biopsied (e.g., encephalocele, facial nerve schwannoma, paraganglioma). In the differential of EAC masses, lesions emanating from the TMJ need to be considered, especially for those based anteriorly. Understanding the extent of TMJ involvement is crucial for surgical planning which optimizes outcome. Goals for therapy are to control the underlying disease process, restore patency of the EAC, improve hearing, and preserve function of TMJ.

Minimally invasive surgical treatment for temporomandibular joint in patients with various rheumatic diseases

Temporomandibular joint (TMJ) involvement occurs in patients with different rheumatic diseases (RDs). Pain, limitation of mouth opening can lead to significant problems in both oral hygiene and when eating. Conservative treatments for TMJ lesions are not always effective. Objective: to evaluate the efficiency of minimally invasive surgical interventions (TMJ arthrocentesis and arthroscopy) in patients with RDs. Patients and methods. The investigation enrolled 64 patients with different RDs (43 with rheumatoid arthritis, 11 with psoriatic arthritis, 8 with systemic lupus erythematosus, and 2 with ankylosing spondylitis) who were divided into three groups in relation to the severity of TMJ involvement in accordance with the Wilkes classification. All the patients underwent TMJ magnetic resonance imaging at baseline and 6 months after treatment. Also at baseline, 14 days, and 1, 6, and 12 months after surgery, the investigators assessed TMJ pain intensity by visual analogue scale and the parameters of mandibular movements. Patients with Wilkes stages IV and V TMJ involvement underwent arthroscopic intervention into the TMJ and those with III stage received TMJ arthrocentesis with arthrolavage. Results and discussion. After surgical treatment, all the groups were noted to have a significant decrease in TMJ pain intensity compared with the baseline level; moreover, the severity of TMJ pain most significantly decreased on day 7 after surgery. Later on, positive changes remained within subsequent follow-up months. There were data similar in the higher degree of mouth opening. The results of surgical treatment in patients with Wilkes stage V TMJ involvement were worse than in those with stages III and IV. Conclusion. Minimally invasive TMJ surgery in patients with RDs is effective and associated with the low frequency of postoperative complications and exacerbations of RDs. The efficiency of minimally invasive TMJ surgery is higher in patients with the early and middle stages of TMJ involvement according to the Wilkes classification. Further investigations are needed to assess the long-term results of minimally invasive TMJ surgery in patients with RDs.

Periarticular Cysts of the Temporomandibular Joint Are More Frequently Synovial Than Ganglion

Differentiating between ganglion and synovial cysts by standard histology is difficult, leading to inaccurate statements on frequency for each of these periarticular lesions. The purpose of this study was to use immunohistochemical (IHC) analysis to 1) calculate the accuracy of the histologic diagnoses, 2) determine the frequency of ganglion and synovial cysts of the temporomandibular joint (TMJ), and 3) compare the frequency of these lesions in the TMJ compared with the extracranial skeleton in patients treated at Massachusetts General Hospital (MGH). This is a retrospective cohort study of all patients undergoing treatment of TMJ cysts at MGH from 2001 through 2013. IHC analysis of tissue samples for each patient was completed and compared with the original histologic diagnoses. Categorical variables, including age, gender, and sidedness, were recorded. A natural language search of the MGH Department of Pathology database determined the frequency of extracranial periarticular cysts during the same period. Thirteen patients met the inclusion criteria. Eleven cysts were synovial and 2 were ganglion based on histology. IHC analysis identified 2 false-positive synovial cyst diagnoses, resulting in 100% sensitivity and 50% specificity for the original histologic assessment and a percentage error of 22%. Of the periarticular TMJ lesions, 69% were synovial cysts and 31% were ganglion cysts. The frequency of TMJ versus extracranial ganglion cysts was 0.24%, and the frequency of TMJ versus extracranial synovial cysts was 0.60% based on 3,176 extracranial cysts (1,506 synovial; 1,670 ganglion). This study represents the largest single-institution experience with periarticular cysts of the TMJ, and contrary to previous reports, TMJ cysts appear to be more frequently synovial than ganglion. IHC can be used to overcome the relatively poor specificity of histologic diagnosis of synovial cysts.

The Turin Shroud face: the evidence of maxillo-facial trauma.

The Turin Shroud (TS) is a linen cloth commonly associated with Jesus Christ, his crucifixion and burial. Several medical specialists have debated the injuries of the TS Man, nevertheless there are no detailed and quantitative data about the anatomy of the TS face. The purpose of this study was to analyse the cephalometric measurements of the face image of the TS. The TS face image was acquired by a picture and processed using a cephalometric software, Oris Ceph® (Up to date 2012). The image of the soft tissues was processed in order to obtain skeletal points and a cephalometric analysis of the soft and skeletal tissues was performed. Image processing of the TS face shows that the Man represented in it has undergone a maxillo-facial trauma, especially a left displacement of the mandible, probably due to temporo-mandibular joint lesions. This condition has not been described before, despite several studies on the subject.

Multidetector computed tomography of temporomandibular joint: A road less travelled

This article reviews the imaging anatomy of temporomandibular joint (TMJ), describes the technique of multi-detector computed tomography (MDCT) of the TMJ, and describes in detail various osseous pathologic afflictions affecting the joint. Traumatic injuries affecting the mandibular condyle are most common, followed by joint ankylosis as a sequel to arthritis. The congenital anomalies are less frequent, hemifacial microsomia being the most commonly encountered anomaly involving the TMJ. Neoplastic afflictions of TMJ are distinctly uncommon, osteochondroma being one of the most common lesions. MDCT enables comprehensive evaluation of osseous afflictions of TMJ, and is a valuable tool for surgical planning. Sagittal, coronal and 3D reformatted images well depict osseous TMJ lesions, and their relationship to adjacent structures.

A ganglion cyst of the temporomandibular joint.

A ganglion cyst of the temporomandibular joint.

The temporomandibular joint of California sea lions (Zalophus californianus): Part 1 – Characterisation in health and disease

ObjectivesThis study aimed to characterise the histologic, biomechanical and biochemical properties of the temporomandibular joint (TMJ) of California sea lions. In addition, we sought to identify structure–function relationships and to characterise TMJ lesions found in this species. DesignTemporomandibular joints from fresh cadaver heads (n=14) of California sea lions acquired from strandings were examined macroscopically and microscopically. The specimens were also evaluated for their mechanical and biochemical properties. Furthermore, if TMJ arthritic changes were present, joint characteristics were described and compared to healthy joints. ResultsFive male and 9 female specimens demonstrated macroscopically normal fibrocartilaginous articular surfaces and fibrous discs in the TMJ. Out of the 9 female specimens, 4 specimens had TMJ lesions were seen either in the articular surface or the disc. Histologically, these pathologic specimens demonstrated subchondral bone defects, cartilage irregularities and inflammatory cell infiltrates. The normal TMJ discs did not exhibit significant direction dependence in tensile stiffness or strength in the rostrocaudal direction compared with the mediolateral direction among normal discs or discs from affected joints. The TMJ discs were not found to be anisotropic in tensile properties. This feature was further supported by randomly oriented collagen fibres as seen by electron microscopy. Furthermore, no significant differences were detected in biochemical composition of the discs dependent upon population. ConclusionThe TMJ and its disc of the California sea lion exhibit similarities but also differences compared to other mammals with regards to structure–function relationships. A fibrous TMJ disc rich in collagen with minimal glycosaminoglycan content was characterised, and random fibre organisation was associated with isotropic mechanical properties in the central region of the disc.

Prevalence of signs and symptoms of temporomandibular dysfunction in female adolescent athletes and non-athletes

ObjectivesTo compare the prevalence of signs and symptoms of temporomandibular dysfunction (TMD) in female adolescent athletes and non-athletes and to examine the association between signs and symptoms of TMD in female adolescents in different Tanner stages. MethodsThe subjects were 89 female basketball and handball players ages 10–18 years and 72 female non-athlete adolescents ages 10–19 years selected from the Department of Pediatrics (School of Medicine, Federal University of São Paulo) as a control group. A survey was used to assess the signs and symptoms of TMD. According to the answers on the survey the adolescents were classified in two categories: no signs or symptoms present (score A-absent), at least one sign or symptom present (score P-present). The ones who got score “P” were submitted to a standardized functional examination of the masticatory system by four previously calibrated examiners. Pubertal status was assessed based on physical examination by physicians from our Division. The adolescents were classified according to Tanner stages into three subgroups: subgroup 1 (before the growth spurt), subgroup 2 (growth spurt period), subgroup 3 (end of growth spurt). Significant differences between athletes and non-athletes were assessed for categorical variables (Chi-square and Fisher's exact test) and for continuous variables (Mann–Whitney test). The level of significance used was 5%. There was significant agreement between raters, kappa-values (0.621–1.000) and ICC values (0.757–0.899). ResultsThere was no significant difference between the athletes and non-athletes in exhibiting at least one sign or symptom of TMD (p=0.301). When comparing the adolescents who presented at least one symptom of TMD to the different subgroups of Tanner stages no statistically significant differences were found (p=0.124). ConclusionThe lack of significant differences among female adolescent athletes and non-athletes and among the subgroups of Tanner stages may suggests that although contact sports increase the risk of temporomandibular joint lesions and estrogen levels are risk factor for onset of TMD, they do not impact significantly on the onset of this disorder, when considered alone.

Efficacy of identifying maxillofacial lesions in cone-beam computed tomographs by orthodontists and orthodontic residents with third-party software

The purpose of this study was to determine the ability of orthodontists and orthodontic residents to identify nonorthodontic incidental findings and false positives in cone-beam computed tomography scans. Two groups of 10 cone-beam computed tomography scans containing equal numbers of scans with no, 1, or several abnormal nonorthodontic lesions were selected from a database. Eight orthodontists and 8 orthodontic residents screened the 2 groups of scans before and after a basic cone-beam computed tomography training course. The paired t test was used for statistical analyses. In the initial screening, the orthodontists and residents correctly identified 41.1% of the lesions. This lesion-detection rate improved significantly to a mean of 56.7% after the training course (P <0.0005). In parallel with these findings, the mean percentage of correctly identified extragnathic lesions improved significantly, from 22% to 48% (P <0.0005), and correctly identified temporomandibular joint lesions improved from 20% to 55% (P = 0.01) after the training. In contrast, the rate of correctly identified dentomaxillofacial lesions remained largely unchanged before and after the training. Both groups of evaluators had approximately 5 false positives per 10 scans before training and demonstrated significant decreases in false positives after training. Relative to known error rates in medical radiology, both groups of evaluators had high error rates for missed lesions and false positives before and after training. Given these findings and since the most frequent cause of medical radiology malpractice litigation is due to missed lesions, it is recommended that an appropriately trained radiologist should be involved in reading and interpreting cone-beam computed tomography scans.