Dental malocclusion is not related to temporomandibular joint clicking: a logistic regression analysis in a patient population

Occlusal Features and Temporomandibular Joint Disorder: A Cross-Sectional Study

Background

Understanding the correlation between temporomandibular joint disorder (TMD) parameters and various occlusal features can play a significant role in diagnosing and treating occlusal problems and their potential consequences on TMD.

Objectives

To investigate the relationship of occlusal features and some of the TMD parameters. Study Design and Sampling. The current cross-sectional study was conducted on 200 TMD patients seeking dental treatment at different dental centers in Baghdad city, aged 18-35 years. All participants underwent assessment for occlusal features, which were molar and canine classifications, overjet, posterior buccal or lingual crossbites, and overbites, and TMD parameters (muscle pain, TMJ pain, and clicking) using the Chi-square test for statistical analysis.

Results

Regarding molar classification, there were strong positive correlations between subjects with TMD and having different molar classifications (class I, II, and III) bilaterally or unilaterally; furthermore, there were strong positive correlations between subjects with TMD and having different canine classifications. Moreover, there were significant correlations between subjects with increased, normal, or decreased overjet and the TMD parameters. In addition, there were weak positive correlations between TMD occurrence and buccal or lingual posterior crossbite. On the other hand, there were significant correlations between subjects with a decreased overbite and the presence of TMD parameters.

Conclusion

TMD had a multifactorial background rather than dependability on a specific molar or canine classification type. There was also a correlation between overjet and TMD muscle pain, while decreased overbite was correlated to muscle and TMJ pain. Conversely, there is no vital correlation between posterior buccal or lingual crossbite occurrence and TMD parameters.

Relationship between natural or iatrogenic malocclusions and temporomandibular disorders: A case control study

OBJECTIVE

To investigate the link between malocclusions and temporomandibular disorders (TMD) with a focus on iatrogenic malocclusion. Other etiologies of TMD (oral parafunctions) were also assessed.

METHODS

The prevalence of malocclusions was correlated in two groups: patients with TMD (case group) and patients without TMD (control group). Malocclusions involving dental care were specified. Parafunctions in the case group were assessed.

RESULTS

A statistically significant association between TMD and overbite >4 mm, interferences in laterotrusion, and absence of Angle Class I was shown. A potential deleterious effect of iatrogenic malocclusions was highlighted.

CONCLUSION

The multifactorial etiology of TMD was confirmed because an association between TMD and three malocclusions was found, and all case patients had parafunction(s). Current recommendations advising first a reversible treatment, TMD care should start with a behavioral re-education to remove parafunctions. However, it is essential to avoid creating iatrogenic malocclusion during dental care.

Centric relation-A biological perspective of a technical concept

BACKGROUND

Few terms and concepts have been so extensively debated in dentistry as the words 'centric relation' (CR). Debates involve its biological, diagnostic and therapeutic usefulness.

METHODS

A review of the literature on the current concepts on CR as a diagnostic or therapeutic aid in dentistry was provided. Clinical trials assessing the superiority of one CR recording method over the others to identify patients with temporomandibular disorders (diagnostic use) or to manage patients with prosthodontic or orthodontic needs (therapeutic use) were tentatively included.

RESULTS

Due to the absence of literature addressing either of the above targets, a comprehensive overview was provided. The diagnostic use of CR as a reference position to identify the correct position of the temporomandibular joint condyle within the glenoid fossa is not supported and lacks anatomical support. From a therapeutic standpoint, the use of CR can be pragmatically useful in prosthodontics as a maxillo-mandibular reference position when occlusal re-organization is warranted and/or when the position of maximum intercuspation is no longer available.

CONCLUSIONS

The derived occlusal goals from a diagnostic misuse of CR are generally the result of circular reasoning, that is a technique is based on the recording of a certain condylar position that is believed to be 'ideal' and the treatment is considered successful when such position is shown by the specific instrument that was manufactured for that purpose. The term 'Centric Relation' might be replaced with the term 'Maxillo-Mandibular Utility Position'.

The Effect of TMJ Intervention on Instant Postural Changes and Dystonic Contractions in Patients Diagnosed with Dystonia: A Pilot Study

(1) Background: The aim of the present study is to analyze the instant postural changes and changes in the dystonic contractions among patients with dystonia following the use of an intraoral device called a key integrative dynamic TMJ treatment appliance (KIDTA). (2) Methods: Twelve subjects, previously diagnosed with dystonia were enrolled. Their existing records were utilized to assess the changes in their posture and dystonic contractions. The posture analysis was conducted using a mobile application (APECS). The initial records (T0) and records acquired after the delivery of the KIDTA (T1) were utilized in the analysis. The Wilcoxon signed-rank test was performed to compare parameters between T0 and T1, with a significance level set at p < 0.05. (3) Results: Based on the Wilcoxon signed-rank test, statistically significant differences in T1 compared to T0 were observed in the severity of dystonic spasms, body alignment, head shift, head tilt, shoulder alignment, shoulder angle, axillae alignment, ribcage tilt, pelvic tilt, knee angle, and tibia angle (p < 0.05). (4) Conclusions: Within the limitations of the present pilot study, an intervention to the TMJ through a KIDTA appliance seems to mitigate the severity of dystonic contractions and improve the posture with respect to certain postural parameters.

Malocclusion Complexity in Patients with Disc Displacement Disorders: A Case-Control Study

This study aimed to determine the possible association between disc displacement (DD) disorders and malocclusion complexity. This cross-sectional study was carried out using a case-control design. The Research Diagnosis Criteria for Temporomandibular Disorders were used to identify cases and controls. The Index of Complexity, Outcome, and Need (ICON) was used to quantify malocclusion complexity as easy, mild, moderate, difficult, or very difficult. A total of 310 subjects were included: 130 cases and 180 controls. A binary logistic regression (p < 0.05) was used to identify associations. The odds ratio (OR) was also calculated. DD was associated with sex, age, and malocclusion complexity (p < 0.05). The malocclusion complexity comparison showed that 89.3% of the controls fell within the easy-moderate levels of the ICON, whereas 85.4% of the cases were in the moderate-very difficult levels (p ≤ 0.001). Difficult and very difficult malocclusions had high ORs (9.801 and 9.689, respectively) compared to the easy cases. In conclusion, patients with malocclusion complexity levels classified as difficult or very difficult have greater odds of presenting DD.

Temporomandibular disorders in children and adolescents: A review

BACKGROUND

Temporomandibular disorders (TMD) are generally observed in individuals between the ages of 20 and 40 years. TMD have also been described in children and adolescents but are still not widely detected and treated in routine practice. Through a literature review, this work aims to improve the diagnosis and management of TMD in children and adolescents by dentists.

METHODS

This literature review was performed by a computerized search of the database PubMed for published articles on TMD in children and adolescents. Articles evaluating the prevalence, etiologies and risk factors, diagnosis, signs, and symptoms as well as the comorbidities of TMD, published between 2001 and 2022, were included in this review.

RESULTS

A total of 51 articles were included. Most of studies reported a prevalence of over 20%, with a higher prevalence in females. The two most common diagnoses were myofascial pain and disk displacement with reduction. Headaches were often associated with the condition. The management of TMD in children and adolescents has been poorly studied.

CONCLUSION

TMD frequently affect children and adolescents. Therefore, for prevention purposes, an examination of the masticatory system should be included in the dental check-up. Early diagnosis is essential in order to limit effects on their growth, development, and quality of life. TMD management is not currently validated for children and adolescents. Noninvasive and reversible care should be preferred.

Temporomandibular Disorders and Dental Occlusion: What Do We Know so Far?

Throughout the recorded history in the literature of temporomandibular disorders (TMD) there have been a variety of opinions as to its primary cause. Those supporting an occlusal basis of TMD opined that occlusal dysfunction is either the primary cause for or a significant etiopathogenic factor in the causation of TMD. Most of the current literature, however, points to evidence in another direction and questions the causal role of occlusion and occlusal disharmony in TMD etiopathogenesis. Recognition of this evidence-based literature is paramount in eliminating and preventing the chances of overtreatment of patients with TMD.

Analysis of the relationship between condylar changes and anterior disc displacement with reduction: a preliminary study

OBJECTIVES

To predict temporomandibular joint (TMJ) anterior disc displacement with reduction (ADDWR) from condylar shape, position, and dimensions obtained from CBCT images.

METHODS

This cross-sectional study was performed on 17 patients suffering from temporomandibular disorders diagnosed by history taking according to the chart of the American Association of orthodontists, clinical examination according to the Helkimo index and MRI. CBCT and MRI examinations were performed within one-week interval. Disc position, diagnosed by MRI was used as the gold standard. TMJs with posterior disc displacement or anterior disc displacement without reduction were excluded. Qualitative and quantitative analyses were performed on CBCT images to find the correlation between condylar variables and ADDWR. A logistic regression model was created to estimate ADDWR from condylar dimensions (height, width and depth).

RESULTS

Condylar shape and condylar position in the glenoid fossa were significantly correlated with ADDWR (P < 0.05). Condylar width, height and depth were significantly smaller in condyles with ADDWR compared to condylar dimensions in normal disc position. Logistic regression analysis could be used to predict the probability of anterior disc displacement with reduction from condylar dimensions.

CONCLUSION

Condylar shape, position, and dimensions assessed by CBCT are significantly correlated with ADDWR of the TMJ. Substituting the values of condylar width, height and depth in the equation suggests the probability of ADDWR.

Efficacy of Botulinum Toxin Type-A I in the Improvement of Mandibular Motion and Muscle Sensibility in Myofascial Pain TMD Subjects: A Randomized Controlled Trial

This study assessed the effects of botulinum toxin type A (BoNT-A) in mandibular range of motion and muscle tenderness to palpation in persistent myofascial pain (MFP) patients (ReBEC RBR-2d4vvv). Eighty consecutive female subjects with persistent MFP, were randomly divided into four groups (n = 20): three BoNT-A groups with different doses and a saline solution group (placebo control group). Treatments were injected bilaterally in the masseter and anterior temporalis muscle in a single session. Clinical measurements of mandibular movements included: pain-free opening, maximum unassisted and assisted opening, and right and left lateral excursions. Palpation tests were performed bilaterally in the masseter and temporalis muscle. Follow-up occurred 28 and 180 days after treatment. For the statistical analysis the Mann–Whitney U-test with Bonferroni correction was used for groups comparisons. Regardless of dose, all parameters of mandibular range of motion significantly improved after 180 days in all BoNT-A groups, compared with the control group. Palpation pain over the masseter and temporalis muscles were significantly reduced in all BoNT-A groups regardless of dose, compared with the control group, after 28 and 180 days of treatment. Independent of doses, BoNT-A improved mandibular range of motion and muscle tenderness to palpation in persistent MFP patients.

TMJ Position in Symmetric Dentofacial Deformity

The aim of this research was to analyze the facial class, presence of malocclusion, and the mandibular plane and to relate this to the mandibular condyle position. A cross-sectional study in subjects under analysis for orthognathic surgery was done. The mandibular plane, the gonial angle, and the molar class were included to compare the coronal and sagittal position of the condyle and the joint space observed in the CBCT. The measurements were obtained by the same observer at an interval of two weeks. In addition, the Spearman test was performed to determine the correlation using a p value < 0.05 to observe any significant differences. Eighty-nine male and female subjects (18 to 58 years old, 24.6 ± 10.5) were included. In the coronal section, subjects with CIII had a greater mediolateral distance (MLD, p = 0.0001) and greater vertical distance (SID, p = 0.0001) than subjects with CII. In terms of the skeletal class and the mandibular plane, it was observed that subjects in the CII group had a greater mandibular angle (open angle) (p = 0.04) than the CII group and was related to the anterior position of the condyle. The most anterior condylar position was observed in the CII group (p = 0.03), whereas a posterior condylar position was significant in CIII subjects (p = 0.03). We can conclude that the sagittal position of the TMJ was related to the mandibular plane and the skeletal class showing a higher mandibular angle and most anterior position of the condyle in CII subjects and a lower mandibular angle and most posterior position of the condyle in CIII subjects. The implications for surgical treatment have to be considered.

Binary Response Analysis Using Logistic Regression in Dentistry

Multivariate analysis with binary response is extensively utilized in dental research due to variations in dichotomous outcomes. One of the analyses for binary response variable is binary logistic regression, which explores the associated factors and predicts the response probability of the binary variable. This article aims to explain the statistical concepts of binary logistic regression analysis applicable to the field of dental research, including model fitting, goodness of fit test, and model validation. Moreover, interpretation of the model and logistic regression are also discussed with relevant examples. Practical guidance is also provided for dentists and dental researchers to enhance their basic understanding of binary logistic regression analysis.

The Association between Occlusal Features and Temporomandibular Disorders in Northern Jordan: A Cross-sectional Study

Objective:

To evaluate the possible correlation between basic occlusal features and the outcomes of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) Axis I.

Materials and Methods:

A convenient sample of Northern Jordanians was used in the study. Participants were examined in accordance with DC/TMD protocol. Nine occlusal features represented the independent variables; overjet, overbite, midline deviation, pain-free opening, maximum assisted opening, maximum unassisted opening, lateral excursions and protrusion, in addition to the opening pattern (classified as straight, corrected deviation and uncorrected deviation). DC/TMD diagnostic outcomes and their associated features represented the dependent variables, namely, pain-related TMD, Intra-articular Disorders (IAD), Degenerative Joint Disease (DJD), joint sounds (clicking and crepitus), joint locking and headache attributed to TMD. Binary logistic regression, multinomial logistic regression and Chi-square tests were used for statistical analyses.

Results:

A total of 400 participants represented the study population (mean age = 32.3±12.4 years, males=48%, females=52%). 71 subjects (18%) were diagnosed with pain-related TMD, 52 (13%) with IAD, 6 (1.5%) with DJD and 38 (10%) with headache due to TMD. Gender had a significant correlation with pain-related TMD (p= 0.014, OR= 2.16). Maximum pain free opening had a significant inverse relationship with pain related TMD (p= 0.013, OR=0.94), while midline deviation and corrected deviation mouth opening pattern had a significant correlation with IAD (p= 0.04,0.02, OR= 1.30,2.74, respectively). Overbite, midline deviation and pain free opening were significantly associated with unilateral open/close clicking (p= 0.04,0.05,0.03, OR= 0.77, 1.31, 0.94, respectively).

Conclusion:

There is a minimal clinical significance of the correlation between dental occlusion and TMD.

Graded exposure and orthopedic manual physical therapy for kinesiophobia and function in chronic temporomandibular dysfunction: A case report

BACKGROUND

This case report describes the successful use of multi-modal physical therapy (PT), including orthopedic manual physical therapy (OMPT) and graded exposure, in a patient with chronic temporomandibular dysfunction (TMD).

CLINICAL PRESENTATION

A 41-yr old female presented with a five-year history of bilateral chronic myofascial TMD and comorbid neck/right arm pain. The patient was treated for 12 weeks with a focus on OMPT and graded exposure. The patient demonstrated clinically significant improvements on the Tampa Scale of Kinesiophobia-TMD, maximal mouth opening, Global Rating of Change, and Jaw Functional Limitation Scale.

CLINICAL RELEVANCE

Mechanisms underlying chronic TMD are complex. Current evidence supports PT management of physical impairments; however, neglecting central drivers or psychosocial factors may result in suboptimal outcomes. Physical therapists are able to address both peripheral and central mechanisms of pain, and future research should examine the utilization of multi-modal PT to improve kinesiophobia and function in patients with chronic TMD.

Long-term Changes of Temporomandibular Joint Osteoarthritis on Computed Tomography

This study aimed to understand long-term changes of the osteoarthritic temporomandibular joint (TMJ) condyle using computed tomography (CT) and to verify its correlation with clinical characteristics of temporomandibular disorders. Eighty-nine patients (152 joints; 76 female, 13 male) who had taken follow-up CTs (mean follow-up period: 644.58 ± 325.71 days) at least once in addition to their initial evaluation were selected. Cross-sectional demographic and clinical data and longitudinal CT images were collected. Data were analyzed by analysis of variance and logistic regression. Overall destructive change index (number of TMJ condyle sections in which destructive change was observed) decreased from 1.56 to 0.66. Improvement was seen in 93 joints (61.2%) and 27 joints (17.8%) worsened. In the pain positive group, both initial and final destructive change index were significantly higher compared to the pain negative group (p = 0.04). Occlusal stabilization splint therapy and nonsteroidal anti-inflammatory drug administration showed a significant effect on improving the prognosis of TMJ osteoarthritis (p = 0.015 and 0.011). In conclusion, TMJ osteoarthritis showed long-term improvement in the majority of cases. TMJ osteoarthritis accompanied by pain showed unfavorable prognosis with additional bone destruction. Occlusal stabilization splint and nonsteroidal anti-inflammatory drug administration were beneficial on the prognosis of TMJ osteoarthritis.

Evaluation of the Use of a Force Diagram in the Management of Temporomandibular Joint Sounds: A Prospective Cross-sectional Study

Context

Occlusal splints are widely used in clinical practice as a noninvasive treatment for patients with temporomandibular disorders (TMDs) and for reduction of TMD-related symptoms. A force diagram allows a health care professional to evaluate the interactions of loads caused by muscular effort, which are sensed by the teeth and the temporomandibular joint during the protrusive movement of the mandible.

Objective

To evaluate the efficacy of occlusal splints combined with occlusal adjustment (OA) based on a force diagram in the management of joint sounds (clicking and crepitation).

Methods

Patients were examined clinically and administered a questionnaire for the diagnosis of TMD and orofacial pain. Patients were then assigned to 1 of 2 splint therapies: (1) an anterior bite plane of the front-plateau type (FP) or (2) a maxillary muscle relaxation appliance (MRA), both combined with OA based on a force diagram performed at 6 visits, with an interval of 24 to 48 hours between each visit. To measure the effects of treatment, at each of the 6 visits, patients also rated the severity of their TMD-related symptoms on a visual analog scale. Data were dichotomized into presence and absence of symptoms and compared using the McNemar test.

Results

A total of 199 patients were included in the study. At baseline, 38 patients (19.1%) had crepitation and 161 (80.9%) had clicking. A total of 150 patients were treated with FP+OA, with a statistically significant reduction in the number of patients reporting clicking (42.6%, P<.001) and crepitation (42.9%, P<.001). Among patients treated with MRA+OA (n=49), there was a statistically significant reduction in the number of patients reporting clicking (50%, P<.001). All 3 patients with crepitation in the MRA+OA group reported total remission (P>.05).

Conclusion

The 2 treatment strategies, FP+OA and MRA+OA, improved both clicking and crepitation. Both strategies prioritize the concept of mutually protected occlusion, in which all jaw and temporomandibular joint movements must synchronize, which may be conveniently done using the force diagram.

Comparison of Early Effectiveness of Three Different Intervention Methods in Patients with Chronic Orofacial Pain: A Randomized, Controlled Clinical Trial

Background

Occlusal appliances are still widely used instruments in the management of orofacial pain in dentistry, yet alone or as a part of multimodal therapy. However, some of those modalities have been lacking thorough randomized assessment, and there is a conflicting evidence available. It is hypothesized that pain symptoms might improve faster and in more tangible way due to combined therapy. Also, to our best knowledge, nimesulide was never examined in this aspect, too.

Objective

The aim of this study was to compare early effectiveness of routine intervention methods in patients with myofascial pain (MP) after 3 weeks' notice. Three modalities were evaluated: occlusal appliance (OA) with nonsteroidal anti-inflammatory drug (NSAID) therapy (nimesulide), occlusal appliance with dry needling (DN), and occlusal appliance (OA-control group) therapy.

Design

Randomized controlled clinical trial (RCT) in which ninety patients with MP, who met the inclusion criteria, were randomly assigned to one of the three treatment groups. Sealed, opaque envelopes were used.

Methods

For evaluation, each patient completed a Visual Analogue Scale (VAS) and Sleep and Pain Activity Questionnaire (SPAQ) twice, first at the beginning of the study and again after 3 weeks (0-3).

Results

Posttreatment test comparison between the control group and both treated groups reveal significant differences between the control and the NSAID + occlusal appliance groups. There were also differences reported between the control and the DN + occlusal appliance groups, but these differences were, however, not statistically significant.

Conclusions

Occlusal appliances in conjunction with NSAID showed better orofacial pain relief after 3 weeks of therapy, compared to the use of occlusal appliances alone or in conjunction with dry needling. Additionally, differences between pain perception and quality of life between OA and DN + OA groups were not found to be statistically significant.

Temporomandibular joint disc displacement with reduction: a review of mechanisms and clinical presentation

Disc displacement with reduction (DDWR) is one of the most common intra-articular disorders of the temporomandibular joint (TMJ). Factors related to the etiology, progression and treatment of such condition is still a subject of discussion. This literature review aimed to address etiology, development, related factors, diagnosis, natural course, and treatment of DDWR. A non-systematic search was conducted within PubMed, Scopus, SciELO, Medline, LILACS and Science Direct using the Medical Subjective Headings (MeSH) terms “temporomandibular disorders”, “temporomandibular joint”, “disc displacement” and “disc displacement with reduction”. No time restriction was applied. Literature reviews, systematic reviews, meta-analysis and clinical trials were included. DDWR is usually asymptomatic and requires no treatment, since the TMJ structures adapt very well and painlessly to different disc positions. Yet, long-term studies have shown the favorable progression of this condition, with no pain and/or jaw locking occurring in most of the patients.

Indexes of jaw muscle function in asymptomatic individuals with different occlusal features

This study aims to assess the correlation between indexes of jaw muscle function and dento-skeletal morphology. A sample of 35 temporomandibular disorders-free healthy individuals (10 males, mean age 26.7 ± 9.8 years) underwent surface electromyographic (sEMG) assessment of bilateral masseter and temporalis muscles, to evaluate sEMG activity during maximum voluntary clenching (MVC) with a dedicated device (Easymyo®, T.F.R. Technology, Udine, Italy). Four outcome parameters were assessed for each individual: MCV on cotton rolls; MVC on teeth; chewing on right and left sides; clench/relax test. Electromyographic recordings were assessed based on five standardized indexes of muscle function, to evaluate the degree of muscle asymmetry during static and dynamic function (i.e., percentage overlapping coefficient [POC], Impact, Asymmetry, Activation, and Torque). For each individual, the presence of a number of occlusal and skeletal features was assessed: asymmetry of molar class; deviated incisor midline; deep bite; open bite; and crossbite. Skeletal class and vertical dimension of occlusion were also evaluated. Based on normality distribution of data, t test and analysis of variance, when needed, were used to compare muscle function indexes between individuals with and without the different dento-skeletal features. None of the muscle function indexes (POC, Impact, Asymmetry, Activation, and Torque) was significantly different between individuals with or without the various dental and skeletal features. Gender differences were also not significant (p > 0.05). Despite some minor differences were observed, none of them was significant. Thus, the interaction between form and function is too complex for hypothesizing a simple one-to-one relationship between interarch tooth relationship and muscle function patterns.

Evaluation of occlusion types, pain severity, and onset of complaints in 127 patients with temporomandibular disorders: A retrospective study

Objective: The aims of this study are to evaluate if occlusal types affect the type of temporomandibular disorders and if the onset of complaints are related to the type of internal derangements. Methods: One hundred thirty-four patients were evaluated. Occlusion types were grouped as Angle Class I, II, and III. The temporomandibular disorders were classified as masticatory muscle disorders, anterior disc dislocation with reduction, and anterior disc dislocation without reduction. Results: No significant relationships were found between the occlusion types, pain severity, the onset of the complaints, and the temporomandibular disorders. Premature contacts were found to be significantly higher in Class II and Class III patients, but no significant relations were found between premature contacts and temporomandibular disorders. Discussion: Occlusal features are not discriminant factors in the occurrence of temporomandibular disorders. Also, it cannot be concluded that the longer the patients have temporomandibular disorders, the higher their pain scores will be.

The role of occlusion in temporomandibular disorders (TMD) in the Northern Finland Birth Cohort (NFBC) 1966

OBJECTIVE

To investigate the role of occlusion in temporomandibular disorders (TMDs) in the Northern Finland Birth Cohort 1966 (NFBC 1966).

METHODS

Subjects (n = 1962) participated in clinical medical and dental examinations. The association between TMD signs and diagnoses with occlusal disturbances, i.e. malocclusions and occlusal interferences, was examined. Pearson's chi-square test, as expressed by odds ratios (OR) and 95% confidence intervals (CI) and logistic regression models, were used in the analysis.

RESULTS

A statistically significant association was found between myalgia and lateral scissor bite and also between arthralgia and lateral deviation in the retruded contact position and intercuspal contact position (RCP-ICP) slide. Pain in the masticatory muscles was associated with negative overjet and the amount of RCP-ICP slide.

DISCUSSION

Occlusal factors showed a statistically significant association with TMD. The TMD signs were associated with unstable occlusion, especially the amount and lateral deviation in RCP-ICP slide, as well as negative overjet.

Association of malocclusion, self-reported bruxism and chewing-side preference with oral health-related quality of life in patients with temporomandibular joint osteoarthritis

OBJECTIVES

The aim of this study was to evaluate the association of oral health-related quality of life (OHRQoL) with malocclusion and self-reported bruxism and chewing-side preference (CSP) in patients with temporomandibular joint osteoarthritis (TMJ-OA).

METHODS

This study involved 511 patients diagnosed with TMJ-OA. Each participant completed the Chinese version of the 14-item Oral Health Impact Profile (OHIP-C14) questionnaire and received a clinical examination concerning malocclusion (posterior crossbite, overbite, overjet and anterior open bite). Also patients' self-reported awake bruxism (AB), sleep bruxism (SB) and CSP based on the Oral Behavior Checklist (OBC) were recorded. The associations of OHIP-C14 with malocclusion and self-reported bruxism and CSP were assessed using multiple linear regression analysis.

RESULTS

Posterior crossbite, overbite, overjet and anterior open bite were not significantly associated with either the total OHIP-C14 score or the scores of each domain of OHIP-C14. AB was significantly associated with both the total OHIP-C14 score and the scores of each domain with the largest standardised coefficients. CSP was significantly associated with both the total OHIP-C14 score and the scores of the psychological and social domains. SB was significantly associated with the scores of both the function limitation and psychological disability domains.

CONCLUSIONS

Malocclusion is not significantly associated with OHRQoL in patients with TMJ-OA. Self-reported AB is highly associated with OHRQoL in patients with TMJ-OA, while self-reported SB and CSP are both moderately associated with OHRQoL in patients with TMJ-OA.

Management of pain in TMD patients: Bio-oxidative ozone therapy versus occlusal splints

OBJECTIVE

To compare the effects of bio-oxidative ozone application with occlusal splints in temporomandibular disorder (TMD) patients with pain.

METHODS

Forty participants were selected after the diagnosis of TMD and randomly divided into two groups: ozone group (OG, n = 20) and occlusal splint group (OCSG, n = 20). Ozone was applied to patients three times per week, for a total of six sessions. Patients in the OCSG were instructed to use occlusal splints every night over a period of four weeks.

RESULTS

Mandibular movements showed significant differences for the time factor in OG and OCSG. Pressure pain thresholds of the temporal and masseter muscles at follow-up were significantly higher in the OCSG group. Both treatments statistically decreased the visual analog scale (VAS) scores. However, no statistically significant difference was observed between groups after the application of treatments.

DISCUSSION

Occlusal splint treatment is still the gold treatment modality for objective pain relief in patients with TMD pain.

Centric relation-intercuspal position discrepancy and its relationship with temporomandibular disorders. A systematic review

OBJECTIVE

The objective of this study is to assess the relationship between centric relation-intercuspal position discrepancy (CR-ICP discrepancy) and temporomandibular disorders (TMDs), by systematically reviewing the literature.

MATERIALS AND METHODS

A systematic research was performed between 1960 and 2016 based on electronic databases: PubMed, Cochrane Library, Medline, Embase, Scopus, EBSCOhost, BIREME, Lilacs and Scielo, including all languages. Analytical observational clinical studies were identified. Two independent authors selected the articles. PICO format was used to analyze the studies. The Newcastle-Ottawa Scale (NOS) was used to verify the quality of the evidence.

RESULTS

Four hundred and sixty-seven potentially eligible articles were identified. Twenty studies were analyzed, being grouped according to intervention in studies in orthodontic patients (n = 3) and studies in subjects without intervention (n = 17). Quality of evidence was low, with an average score of 3.36 according to Newcastle-Ottawa Scale. In most studies, the presence of CR-ICP discrepancy is associated with the presence of muscle (pain) and joint disorders (noise, disc displacement, pain, crepitus, osteoarthritis and osteoarthrosis). However, the lack of consistency of the results reported reduces the validity of the studies making it impossible to draw any definite conclusions.

CONCLUSIONS

Because of the heterogeneity of the design and methodology and the low quality of the articles reviewed, it is not possible to establish an association between CR-ICP discrepancy and TMD. The consequence of CR-ICP discrepancy on the presence of TMD requires further research, well-defined and validated diagnostic criteria and rigorous scientific methodologies. Longitudinal studies are needed to identify CR-ICP discrepancy as a possible risk factor for the presence of TMD.

Personality traits are potentially associated with the presence of chronic temporomandibular joint pain in patients without effusion as determined by T-2 weighted magnetic resonance

OBJECTIVE

The study aimed at investigating personality traits in chronic temporomandibular joints (TMJ) pain patients with and without joint effusion.

METHODS

Two groups of chronic TMJ pain patients were recruited. The TMJ pain control group was composed of patients showing magnetic resonance imaging (MRI) signs of TMJ effusion, while the TMJ pain test group included patients with chronic TMJ pain seemingly not justified, due to the absence of MRI-detected disorders. A third set of pain free individuals was selected as a comparison group. All patients completed a personality assessment with the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) instrument, and the between-group differences were assessed for significance by performing an analysis of variance test.

RESULTS

Patients of the TMJ pain test group had higher scores than subjects belonging to the TMJ pain and pain-free control groups in almost all of the MMPI-2 clinical scales. A significant difference was shown for the scales related to concerns about physical health (Scale 1-Hs; F = 7.74; p = .001) and physical symptoms (Scale 3-Hy; F = 8.43; p = .001).

CONCLUSIONS

Chronic TMJ pain patients without MRI-detected TMJ effusion have a different personality profile than patients with TMJ effusion and pain-free individuals, regarding high levels of concerns about physical health and physical symptoms.

CLINICAL IMPLICATIONS

This study has important clinical implications for temporomandibular disorders practitioners, providing suggestions that symptoms in the TMJ area are not only related to a physical disorder. The possible existence of a psychologically modulated condition in patients who refer pain in the TMJ area without signs of effusion should be carefully taken into consideration.

Dental Angle class asymmetry and temporomandibular disorders

OBJECTIVES

The aim of this study was to determine whether there is an association between the presence of asymmetric molar or canine Angle classes on the two sides and the presence of temporomandibular joint dysfunction (TMD).

MATERIALS AND METHODS

Participants to the study were divided into two groups: TMD group (90 patients) or a control group (58 patients). In the TMD group, clinical assessment for TMD was performed according to the Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guidelines by the same two trained examiners. In both groups, all subjects underwent an assessment of dental occlusion, focusing on the assessment of bilateral canine and molar Angle class relationship. The study protocol was reviewed and approved by the Institutional Review Board of the University of Padova, and each participant gave written consent to take part in the investigation.

RESULTS

TMJ pain was diagnosed in 58, disk displacement in 96, arthrosis in 17, and muscle pain in 46 individuals. Molar Angle class was symmetrical in 86 individuals and asymmetrical in 62 subjects. Molar Angle class was not correlated with any of the TMD diagnoses. Canine Angle class was correlated with TMJ arthrosis. Correlation values with the other TMD diagnoses were low and were not significant.

CONCLUSIONS

It can be suggested that an association between dental Angle class asymmetry and TMDs does not exist and that the role of dental asymmetries as a factor correlated with the presence of TMD signs and symptoms is minimal.

Assessment of electromyographic activity in patients with temporomandibular disorders and natural mediotrusive occlusal contact during chewing and tooth grinding

OBJECTIVES

The aim of this study was to investigate whether the presence of a natural mediotrusive contact influences electromyographic (EMG) pattern activity in patients with temporomandibular disorders (TMDs).

METHOD

Bilateral surface EMG activity of the anterior temporalis (AT), masseter (MM), and sternocleidomastoid (SCM) muscles was recorded in 43 subjects during unilateral chewing and tooth grinding. Thirteen patients had TMD and a natural mediotrusive contact (Group 1), 15 had TMD without a natural mediotrusive contact (Group 2), and 15 were healthy subjects without mediotrusive contacts (Group 3). All subjects were examined according to the Research Diagnostic Criteria for TMD (RDC/TMD). All EMG values were standardized as the percentage of EMG activity recorded during maximum isometric contraction on cotton rolls.

RESULTS

EMG activity from all muscles measured showed no significant differences between groups during chewing and grinding. Overall, in all groups, the EMG activity during chewing was higher in the working side than the non-working side in AT and MM muscles. During grinding, these differences were only found in masseter muscles (mainly in eccentric grinding). SCM EMG activity did not show significant differences during chewing and grinding tasks. Symmetry, muscular balance, and absence of lateral jaw displacement were common findings in all groups.

DISCUSSION

EMG results suggest that the contribution of a natural mediotrusive occlusal contact to EMG patterns in TMD patients is minor. Therefore, the elimination of this occlusal feature for therapeutic purposes could be not indicated.

Orthodontics is temporomandibular disorder-neutral

OBJECTIVES

To assess if subjects with a clinical diagnosis of temporomandibular disorders (TMDs) have a similar prevalence of orthodontic history as a population of TMD-free individuals and to assess if those subjects who have a history of ideal orthodontics have fewer symptoms than those with a history of nonideal orthodontics.

MATERIALS AND METHODS

Two groups of age- and sex-matched individuals belonging to either a study ("TMD") or a control group were recruited. Subjects who underwent orthodontic treatment were classified as having a history of ideal or nonideal orthodontics based on the current presence of normal values in five reference occlusal features.

RESULTS

The correlation with a history of orthodontic treatment was not clinically significant for any of the TMD diagnoses (ie, muscle pain, joint pain, disc displacement, arthrosis), with Phi (Φ) coefficient values within the -0.120 to 0.058 range. Within the subset of patients with a history of orthodontics, the correlation of ideal or nonideal orthodontic treatment with TMD diagnoses was, in general, not clinically relevant or was weakly relevant.

CONCLUSIONS

Findings confirmed the substantial absence of clinically significant effects of orthodontics as far as TMD is concerned. The very low correlation values of a negative or positive history of ideal or nonideal orthodontics with the different TMD diagnoses suggest that orthodontic treatment could not have a true role for TMD.

The role of occlusal factors on the occurrence of temporomandibular disorders

AIMS

The aim of this study was to investigate the relationship between occlusal factors and temporomandibular disorders (TMD).

METHODOLOGY

One hundred patients were selected among those who sought medical or dental care in public practice in Recife, Brazil. The presence of malocclusions and absence of five or more posterior teeth were evaluated by the clinical exam. TMD diagnosis was given using Research Diagnostic Criteria (RDC/TMD). Statistics were carried out using Fisher and Mann-Whitney methods with 5% significance level, as well as multiple logistic regression analysis.

RESULTS

The sample was mainly comprised of women (83%), individuals over 30 years old (57%) and singles (53%). The percentage of TMD and malocclusion in total sample was 42% and 50%, respectively, while in TMD subjects, malocclusion was present in 38.1%. There was no association between TMD and the occlusal factors studied.

CONCLUSION

It can be concluded that malocclusion and loss of five or more posterior teeth does not contribute to TMD.