Repeatability of the Vibroarthrogram in the Temporomandibular Joints.

Current research concerning the repeatability of the joint's sounds examination in the temporomandibular joints (TMJ) is inconclusive; thus, the aim of this study was to investigate the repeatability of the specific features of the vibroarthrogram (VAG) in the TMJ using accelerometers. The joint sounds of both TMJs were measured with VAG accelerometers in two groups, study and control, each consisting of 47 participants (n = 94). Two VAG recording sessions consisted of 10 jaw open/close cycles guided by a metronome. The intraclass correlation coefficient (ICC) was calculated for seven VAG signal features. Additionally, a k-nearest-neighbors (KNN) classifier was defined and compared with a state-of-the-art method (joint vibration analysis (JVA) decision tree). ICC indicated excellent (for the integral below 300 Hz feature), good (total integral, integral above 300 Hz, and median frequency features), moderate (integral below to integral above 300 Hz ratio feature) and poor (peak amplitude feature) reliability. The accuracy scores for the KNN classifier (up to 0.81) were higher than those for the JVA decision tree (up to 0.60). The results of this study could open up a new field of research focused on the features of the vibroarthrogram in the context of the TMJ, further improving the diagnosing process.

Assessment of the Temporomandibular Joint Function in Young Adults without Complaints from the Masticatory System.

Objective of the study was to evaluate the clinical status of the masticatory system in young adults with full permanent dentition and no stomatognathic system complaints. The study involved 186 randomly selected people with full dental arches with normal occlusal conditions corresponding to Angle's Class I aged 18 - 21 years with an average age of 19 years. Subjects were clinically examined and temporomandibular joint (TMJ) vibrations were recorded during open-wide and close movements using BioJVA. Then, patients were categorized into groups according to Piper's classification system. The TMJs of the subjects were categorized according to the values of the vibration energy and the Piper protocol. This detected 33.4% of the joints with loosened ligaments, subluxation in 8.28%, initial signs of disc dysfunction in 5.08% and disc displacement without locking in 1.6 %. Median frequency differed significantly (p < 0.05) between the group of subjects with initial signs of TMJ dysfunction and other groups. Peak Frequency differed significantly (p < 0.05) between the healthy joints and those with TMJ subluxation. In this group of young healthy people, the majority of study joints generated small vibrations. However, a subset of people manifested higher vibrations that may indicate an early stage of TMJ dysfunction. Median Frequency was an important parameter for detecting initial symptoms of TMJ dysfunction. Peak Frequency was an important characteristic parameter for detecting TMJ subluxation.

Comparison of TMJ vibration frequencies under different joint conditions.

OBJECTIVE: To compare 10 Hz wide segments of the 0 to 1000 Hz frequency distributions of vibrations recorded from five stages of internally deranged and asymptomatic temporomandibular joints (TMJs). METHODS: TMJ vibrations were recorded from 236 patients with five stages of TMJ dysfunction: (1) reducing partial disc displacement (PDDR, n=39); (2) acute reducing complete disc displacement (A-DDR, n=39); (3) chronic reducing complete disc displacement (C-DDR, n=55); (4) un-adapted, non-reducing, complete disc displacement (DDUA, n=57); and (5) well adapted, non-reducing, complete disc displacement (DDWA, n=46). A totally asymptomatic control group with quiet TMJs (AQ, n=43) and a group with vibrating TMJs (AWV, n=93), but otherwise asymptomatic were also recorded. Frequency distributions were calculated for each group using discrete Fourier transform methods in 10 Hz increments (0-10 Hz, 10-20 Hz,…, 990-1000 Hz). The 10 Hz segments were compared between the seven groups using Student's t test with Bonferroni adjustment. RESULTS: There were significant differences (P<0.05) in all 21 comparisons for the three segments between 80 Hz and 110 Hz, in 20 of 21 comparisons between 180 and 200 Hz, in 19 of 21 comparisons between 110 and 180 Hz and between 50 and 80 Hz. DISCUSSION: The segments of the frequency distributions from 80 to 110 Hz provided the best differentiation between all seven groups.

The reproducibility of temporomandibular joint vibrations over time in the human.

The aim of the study was to assess the reproducibility of vibrations recorded from the temporomandibular joint (TMJ) in a group of healthy subjects. The vibrations from TMJ were recorded bilaterally from 34 healthy subjects by electrovibratography in three sessions at intervals of 3 min and again after 1 week. The total integral of the vibration energy, the ratio of the integral between frequencies above 300 Hz and below 300 Hz (ratio of >300 Hz/<300 Hz), peak frequency, median frequency, peak amplitude and distance to centric occlusion position were calculated. Data were analysed with intraclass correlation coefficients (ICC) and two-way anova for repeated measures. All variables showed good to excellent reliability across different sessions (ICCday1 : 0·935-0·987; ICCday2 : 0·910-0·992) and across different days (ICC: 0·738-0·907). According to anova for repeated measures, all variables showed good reproducibility (P > 0·05) between sessions at the same day. There was no significant difference between the 2 days for the frequency-related variables including peak frequency (P = 0·083), median frequency (P = 0·188) and ratio of >300 Hz/<300 Hz (P = 0·26). There was a statistical difference between the 2 days for the intensity-related vibration variables including total integral (P = 0·045) and peak amplitude (P = 0·026). The wave patterns of the power-frequency spectra were qualitatively similar over both the sessions and days. Joint vibration analysis could provide a fast, non-invasive, and repeatable method to record the status of TMJ. Further studies are needed to identify the characteristic waveforms for different subgroups of temporomandibular disorders and to evaluate the possibility of diagnostic value.

Correlations of temporomandibular joint morphology and position using cone-beam computed tomography and dynamic functional analysis in orthodontic patients: A cross-sectional study.

Objective: To correlate temporomandibular joint (TMJ) morphology and position with cone-beam computed tomography (CBCT) images, Joint Vibration Analysis (JVA), and Jaw Tracker (JT) to develop a radiation-free, dynamic method for screening and monitoring the TMJ in orthodontic patients. Methods: A total of 236 orthodontic patients without symptoms of TMJ disorders who had undergone CBCT were selected for the JVA and JT tests in this cross-sectional study. TMJ position and morphology were measured using a three-dimensional analysis software. JT measurements involved six opening-closing cycles, and JVA measurements were performed using a metronome to guide the mouth opening-closing movements of the patients. The correlations among the three measuring devices were evaluated. Results: Abnormalities in condylar surface morphology affected the mandibular range of motion. The cut-off value results show that when various measurement groups are within a certain range, abnormalities may be observed in morphology (area under the curve, 0.81; P < 0.001). A 300/< 300 Hz ratio ≥ 0.09 suggested abnormal morphology (P < 0.05). Correlations were observed among the maximum opening velocity, maximum vertical opening position, and joint spaces in the JT measurements. Correlations were also observed between the > 300/< 300 Hz ratio, median frequency, total integral, integral < 300 Hz, and peak frequency with joint spaces in the JVA measurements. Conclusions: JT and JVA may serve as rapid, non-invasive, and radiation-free dynamic diagnostic tools for monitoring and screening TMJ abnormalities before and during orthodontic treatment.

An evaluation of the effect of wearing complete dentures on temporomandibular joint vibrations over time using the joint vibration analyzer.

Aim: To evaluate the changes in temporomandibular joint (TMJ) vibrations after insertion of the complete denture in edentulous patients. Settings and Design: An observational in vivo study conducted to evaluate the changes in maximum mouth opening, total integrals, peak amplitude, and peak frequency in TMJ vibrations on the day of complete denture insertion and 6 months of follow up. Materials and Methods: Twenty patients (male: 12 and female: 8) were selected for the fabrication of balanced complete dentures following conventional procedure. Joint vibration analysis was recorded using the joint vibration analyzer. The patients were instructed to open as wide as possible and close to the intercuspal position with rhythmic speed following the metronome projected on the screen. The TMJ vibrations were amplified and displayed as waveforms in a graphical representation by system software. Statistical Analysis Used: Wilcoxon test. Results: A significant decrease in the total integral (P = 0.001) and peak amplitude (P = 0.044) for opening and closing movements of the left and right joints was observed. There was no significant change in maximum mouth opening (P = 0.624). A decrease in peak frequency was noted only at left opening movements between the day of insertion and at 6 months (P = 0.025). Conclusion: The function of TMJ mechanics was improved till 6 months after insertion of complete denture with balanced articulation (BA).

The Prevalence and Overlaps of Temporomandibular Disorders in Patients with Myofascial Pain with Referral-A Pilot Study.

The aim of the study was to evaluate the temporomandibular joint, the prevalence of single and multiple diagnosis and potential sided domination of temporomandibular dysfunction in patients with temporomandibular disorder-myofascial pain with referral. The study group enrolled 50 people-37 females and 13 males between 18 and 25 years old with an average age of 23.36 ± 2.14. The patients underwent joint vibration analysis. Sixty seven percent of all examined tem-poromandibular joints were classified as group I according to Mark Piper's classification. Class IIIA appeared in 17% of joints. Eight percent of temporomandibular joints were classified as class IVA. There were no statistically significant differences in the prevalence of temporomandibular disorder with respect to gender (p = 0.838639). The relatively high prevalence of multiple diagnoses proved the overlapping nature of muscle and intraarticular disorders. Twenty eight percent of the subjects suffered from a combination of myofascial pain with referral and bilateral temporoman-dibular dysfunction. In 62% of the patients a lack of intraarticular disorders was reported. The suggestion that there exists sided domination in the occurrence of temporomandibular disorders has not been confirmed. Due to the small sample size, such differences cannot be excluded. Fur-ther research is needed.

Can devices for the instrumental analysis of temporomandibular joints be used interchangeably?

Objective: To compare the results obtained in instrumental analysis of temporomandibular joints function using joint vibration analysis and computerized axiography in healthy young adults.Methods: The study involved 187 people aged 18-21 years old. All the participants were subjected to a clinical examination and instrumental diagnostics that included joint vibration analysis and computerized axiography.Results: Significant differences in the maximum range of condylar movement (p = 0.0001) were reported between the group of people with healthy joints (p = 0.001) and the remaining groups. There were significant statistical differences (p = 0.02) between the group of people with loose articular ligaments and subluxation of the joint in terms of the parameter describing the symmetry of the sagittal position of the condyle on the distance of 5 mm.Discussion: Electrovibratography and computerized axiography did not reveal the same abnormalities in the functioning of the masticatory system.

The role of soft tissue mobilization in reducing orofacial and general complaints in a patient with Kimmerle anomaly and temporomandibular joint disorder: A case report.

Background: Kimmerle anomaly belongs to the anatomic varieties of the first cervical vertebra. The clinical pattern is dominated by vascular- and neurogenic-type headaches, dizziness, decreased postural muscle tension, and vegetative symptoms. Clinical Presentation: A 37-year-old woman who suffered from headache and pain in the left temporomandibular joint underwent clinical examination, electromyography of masticatory muscles, temporomandibular joint vibration analysis, cone beam computed tomography, and soft tissue mobilization. Radiologic examination revealed Kimmerle anomaly on the right side of the atlas. Clinical Relevance: Myofascial release decreased the tension within anatomic structures projected to the vertebral artery groove. Better movements of the cervical spine and fewer headaches were noted. Increased cervical and masseter muscle tension were considered the main cause of the ailments. The proprioceptive system of the cervical spine was accepted as a reason for persistent headaches. Soft tissue mobilization revealed positive healing effect in the patient with temporomandibular joint disorder and Kimmerle anomaly. Abbreviations: C1: First cervical vertebra; DC/TMD: Diagnostic Criteria for Temporomandibular Disorders (DC/TMD); BDI: Beck Depression Inventory; PSS: Perceived Stress Scale; NDI: Neck Disability Index; BioEMG: Surface electromyography; sEMG: Surface electromyography; ICC: Intraclass correlation coefficient; T-Scan® III: computer evaluation of dental occlusion; JVA: Joint Vibration Analysis; CBCT: Cone Beam Computed Tomography; TO: Occlusion time; the time from the first contact of the teeth to the maximum intercuspidation; reference value in patient with natural teeth <0.2 s; TDL: Disclusion time to the left; the time from the maximum intercuspidation to obtain complete lack of the teeth contact in lateral movement to the left; reference value in patient with natural teeth <0.4 s; TDR: Disclusion time to the right; the time from the maximum intercuspidation to obtain complete lack of the teeth contact in lateral movement to the right; reference value in patient with natural teeth <0.4 s; NHP: Natural head position; µSv: micro-Sievert; kV: kilovolt; mA: miliampere; cm: centimeter; µm: micrometer; s: second; Hz: Hertz; C1-C2: Segment of atlas and axis; AOD: Atlantooccipital dislocation; RV: Reference value; TrP: Trigger point; VAS: Visual Analog Scale; CN V: Cranial nerve V, trigeminal nerve; OC-C1: Occiput and first vertebra junction.

Temporomandibular joint vibrations from totally asymptomatic subjects.

OBJECTIVE: Precisely characterize the TMJ vibrations of a youthful, adult and completely asymptomatic population. METHODS: TMJ vibrations were recorded from 237 asymptomatic subjects (163 f, 74 m) at Dayananda Sagar Institute in India. The subjects were selected, examined and informed (WMA Helsinki Declaration). TMJ vibrations were recorded bilaterally during maximal open - close. 6 parameters of the vibrations were analyzed between the left and right sides, between genders and with respect to age. RESULTS: Mean vibration intensity was greater for females (p < 0.01) than males. A portion of the frequency spectrum < 300 Hz was also more intense for females (p < 0.022). Females 18 - 20 years old exhibited higher Peak Amplitude than 27 - 30 year olds (p < 0.025) and lower Median Frequency (p < 0.005). CONCLUSIONS: A significant difference in TMJ vibrations was present between males and females, increased with age in females but not in males.

Evaluation of TMJ sound on the subject with TMJ disorder by Joint Vibration Analysis.

STATEMENT OF PROBLEM: Qualitative and semi-quantitative methods have been developed for TMJ sound classification, but the criteria presented are completely inhomogeneous. Thus, to develop more objective criteria for defining TMJ sounds, electroacoustical systems have been developed. We used Joint vibration analysis in the BioPAK system (Bioresearch Inc., Milwaukee, USA) as the electrovibratography. PURPOSE: The aim of this study was to examine the TMJ sounds with repect to frequency spectra patterns and the integral > 300 Hz /< 300 Hz ratios via six-months follow-up. MATERIAL AND METHODS: This study was done before and after the six-months recordings with 20 dental school students showed anterior disk displacement with reduction. Joint vibrations were analyzed using a mathematical technique known as the Fast Fourier Transform. RESULTS: In this study Group I and Group II showed varied integral > 300 /< 300 ratios before and after the six-months recordings. Also, by the comparative study between the integral > 300 /< 300 ratios and the frequency spectrums, it was conceivable that the frequency spectrums showed similar patterns at the same location that the joint sound occurred before and after the six-months recordings. while the frequency spectrums showed varied patterns at the different locations that the joint sound occurred before and after six-month recordings, it would possibly be due to the differences in the degree of internal derangement and/or in the shape of the disc. CONCLUSIONS: It is suggested that clinicians consider the integral > 300 /< 300 ratios as well as the frequency spectrums to decide the starting-point of the treatment for TMJ sounds.

Evaluation of TMJ sound on the subject with TMJ disorder by Joint Vibration Analysis

STATEMENT OF PROBLEM: Qualitative and semi-quantitative methods have been developed for TMJ sound classification, but the criteria presented are completely inhomogeneous. Thus, to develop more objective criteria for defining TMJ sounds, electroacoustical systems have been developed. We used Joint vibration analysis in the BioPAK system (Bioresearch Inc., Milwaukee, USA) as the electrovibratography. PURPOSE: The aim of this study was to examine the TMJ sounds with repect to frequency spectra patterns and the integral > 300 Hz / 300 / 300 / 300 /< 300 ratios as well as the frequency spectrums to decide the starting-point of the treatment for TMJ sounds.