Computer-assisted surgery with custom prostheses and human amniotic membrane in a patient with bilateral class IV TMJ reankylosis: a case report

A gold-standard technique has yet to be found for the treatment of temporomandibular joint ankylosis (TMJa), particularly in patients with recurring ankylosis. A 58-year-old male patient, with a history of multiple TMJ surgeries and severe limitation of mouth opening (maximum interincisal distance [MID] was 10 mm). Computerised tomography (CT) imaging highlighted a bilateral type IV ankylosis. The surgical guides were manufactured using a 3D printing method after obtaining a proper design of the osteotomy lines. The positioning of the fossa and condyle components of the custom TMJ prosthesis was digitally performed. Osteotomies were carried out using surgical guides and TMJ prostheses were placed as per the virtual planning. A human amniotic mambrana is inserted between the two prosthetic components to avoid ranchylosis. The post-operative CT showed the correct positioning of the condylar prosthesis. MID after 10 days was 37 mm. Total joint reconstruction surgery using 3D virtual surgical planning may be an effective surgical option for achieving a precise surgical outcome and making use of a single-stage approach in cases of TMJa and the use of the amniotic membrane, thanks to its healing properties and reduction of pain perception, seems to improve the quality of the immediate post-operative period.

Temporomandibular Joint Arthrocentesis in Patients with Degenerative Joint Disease: A 10- to 22-year Follow-up

AIMS

To report the effectiveness of temporomandibular joint (TMJ) arthrocentesis with viscosupplementation for degenerative joint disease (DJD) over a long-term (ie, 10-22 years) follow-up.

METHODS

A total of 103 patients aged between 30 and 91 years (13 men and 90 women; mean age 63.7 years) who received a cycle of five arthrocentesis sessions with HA viscosupplementation to manage their symptoms related to TMJ DJD during the time period from 1998 to 2010 were recalled for clinical evaluation. After the treatment cycle, clinical outcomes were assessed based on the following parameters: maximum mouth opening (MO), pain with function (PF), pain at rest (PR), and self-reported chewing efficiency (CE). Data were collected at baseline (T₀) and at successive follow-up assessments, after at least 3 months (T₁) and 1 year (T₂), as per previous publications. Patients who had received treatment at least 10 years prior were then recalled for this study (T₃: 10 to 22 years follow-up). Analysis of variance for repeated measures was performed to assess changes over time.

RESULTS

Significant improvement in all clinical parameters was achieved at T₁ and was maintained for up to 10 years (T₃), with P < .01 for each parameter. At T₃, treatment effectiveness was perceived as excellent by 56% and as good by 26.5% of subjects, while 10.7% perceived a moderate improvement, and 6.8% referred a slight improvement or did not have any improvement. Only seven individuals required additional treatments after T₂.

CONCLUSION

These findings suggest that the symptomatic management of TMJ DJD achieved in the short or medium term with a cycle of arthrocentesis and viscosupplementation was effectively maintained in the long term.

Evaluation of interleukin-1 beta and the ratio of interleukin-1 beta to interleukin-1 receptor antagonist in gingival crevicular fluid during orthodontic canine retraction

BACKGROUND

Orthodontic tooth movement (OTM) is a complex phenomenon mediated by cytokines, of which interleukin-1 beta (IL‑1β) is potently involved in the remodeling of the periodontal ligament (PDL) and bone. Whether the pattern of IL‑1β release differs at the sides of tension and compression is not yet clarified.

OBJECTIVES

The aim of the present study was to evaluate the level of IL‑1β and the ratio of IL‑1β to interleukin-1 receptor antagonist (IL‑1RA) in gingival crevicular fluid (GCF) at the tension and compression sides during orthodontic canine retraction.

MATERIAL AND METHODS

Seventeen patients scheduled for orthodontic treatment with bilateral extraction of maxillary first premolars and canine retraction were enrolled. Tooth 2.3 was retracted, teeth 1.3 and 3.3 served as controls. Gingival crevicular fluid samples were collected from the tension and compression sides of each tooth at baseline (before the 1st activation - day 0) and at days 2 and 7, and then again before the 2nd activation (day 28) and at days 30 and 35. The levels of IL‑1β and IL‑RA were evaluated with the enzyme-linked immunosorbent assay (ELISA).

RESULTS

After the 1st activation, a statistically significant increase in the level of IL‑1β was observed at teeth 2.3 (p < 0.03 mesially and p < 0.05 distally) and 1.3 (p < 0.05 mesially and distally), both at the tension and compression sides. The 2nd activation resulted in a gradual increase in the IL‑1β level at both canines; however, statistical significance was reached only for tooth 2.3 (p < 0.05 mesially and p < 0.02 distally). In terms of the IL‑1β/IL‑1RA ratio, a significant increase was observed only at the compression side of the experimental tooth (p < 0.01).

CONCLUSIONS

An increase in the IL‑1β level in GCF was observed both at the tension and compression sides of the actively retracted canine 2.3 as well as the contralateral canine 1.3; a significant rise in the IL‑1β/IL‑1RA ratio was noted only at the compression side of the experimental tooth 2.3, indicating the zone of active bone resorption.

Sleep bruxism and temporomandibular disorders: A scoping review of the literature

OBJECTIVE

To provide a scoping review of the literature by assessing all the English-language papers that investigated the relationship between sleep bruxism (SB) and temporomandibular disorders (TMDs).

STUDY DATA AND SOURCES

A search was performed in the National Library of Medicine (PubMed) and Scopus databases, in order to identify all the articles published assessing the relationship between SB and TMDs, by several different approaches. The selected articles were then structurally read and summarized in PICO tables. The articles were selected independently by the two authors.

STUDY SELECTION

Out of 185 references that were initially retrieved, 47 articles met the inclusion criteria and were thus included in the review. The studies were divided into four categories based on the type of SB assessment: 1. questionnaire/self-report (n = 26), 2. clinical examination (n = 7), 3. electromyography (EMG) (n = 5), and 4. polysomnography (PSG) (n = 9).

CONCLUSIONS

Studies based on questionnaire/self-report SB featured a low specificity for SB assessment, and in general they found a positive association with TMD pain. On the contrary, instrumental studies (i.e., electromyography, polysomnography) found a lower level of association or even a negative relationship between SB and TMD pain. Findings from this updated review confirmed the conclusions of a previous review by Manfredini & Lobbezoo, suggesting that literature findings on the relationship between SB and TMDs are dependent on the assessment strategies that are adopted for SB. Future studies should consider SB as a multifaceted motor behavior that must be evaluated in its continuum spectrum, rather than using a simplified dichotomous approach of presence/absence.

Transitioning to chronic temporomandibular disorder pain: A combination of patient vulnerabilities and iatrogenesis

Background

Based on a variety of studies conducted in recent years, some of the factors that might contribute to the negative treatment responses of some TMD patients have been elucidated.

Methods

This paper describes known vulnerability factors that make individuals susceptible to developing temporomandibular disorders (TMDs), as well as those that contribute to the perpetuation of such problems. In addition, the topic of iatrogenesis is discussed as a major contributor to the negative outcomes that can be seen in this field.

Results

At the patient level, anatomical, psychosocial and genetic factors may contribute to individual vulnerability. The anatomy and pathophysiology of muscles, joints, disc and nerves may all be involved in predisposing to TMD symptoms, especially when the patients have pain elsewhere in the body. Among the psychosocial factors, some features may be elucidated by the DC/TMD axis II, while others (eg illness behaviour, Munchausen syndrome, lack of acceptance of non‐mechanical approaches) require careful evaluation by trained clinicians. Genetic predisposition to first onset TMDs and to chronification of symptoms has been identified for individuals with certain psychological traits, presence of comorbid conditions and certain abnormal clinical manifestations. Regarding iatrogenesis, sins of omission may influence the clinical picture, with the main ones being misdiagnosis and undertreatment. Joint repositioning strategies, occlusal modifications, abuse of oral appliances, use of diagnostic technologies, nocebo effect and complications with intracapsular treatments are the most frequent sins of commission that may contribute to chronification of TMDs. The patients who present with massive occlusal and jaw repositioning changes combined with persistent severe orofacial pain are not a rarity within TMD and orofacial pain canters; these patients are the most difficult ones to manage because of this horrific combination of negative factors.

Conclusions

The information presented in this paper will help clinicians to understand better why some individuals develop temporomandibular disorders, why some of them will progress to becoming chronic patients, and what the appropriate responses may be.

Signal acquisition and analysis of ambulatory electromyographic recordings for the assessment of sleep bruxism: A scoping review

Background

Ambulatory electromyographic (EMG) devices are increasingly being used in sleep bruxism studies. EMG signal acquisition, analysis and scoring methods vary between studies. This may impact comparability of studies and the assessment of sleep bruxism in patients.

Objectives

(a) To provide an overview of EMG signal acquisition and analysis methods of recordings from limited‐channel ambulatory EMG devices for the assessment of sleep bruxism; and (b) to provide an overview of outcome measures used in sleep bruxism literature utilising such devices.

Method

A scoping review of the literature was performed. Online databases PubMed and Semantics Scholar were searched for studies published in English until 7 October 2020. Data on five categories were extracted: recording hardware, recording logistics, signal acquisition, signal analysis and sleep bruxism outcomes.

Results

Seventy‐eight studies were included, published between 1977 and 2020. Recording hardware was generally well described. Reports of participant instructions in device handling and of dealing with failed recordings were often lacking. Basic elements of signal acquisition, for example amplifications factors, impedance and bandpass settings, and signal analysis, for example rectification, signal processing and additional filtering, were underreported. Extensive variability was found for thresholds used to characterise sleep bruxism events. Sleep bruxism outcomes varied, but typically represented frequency, duration and/or intensity of masticatory muscle activity (MMA).

Conclusion

Adequate and standardised reporting of recording procedures is highly recommended. In future studies utilising ambulatory EMG devices, the focus may need to shift from the concept of scoring sleep bruxism events to that of scoring the whole spectrum of MMA.

Awake Bruxism-Single-Point Self-Report versus Ecological Momentary Assessment

Assessment of awake bruxism (AB) is problematic due to the inability to use continuous recordings during daytime activities. Recently, a new semi-instrumental approach was suggested, namely, ecological momentary assessment (EMA), via the use of a smartphone application. With the application, subjects are requested to report, at least 12 times per day, the status of their masticatory muscle activity (relaxed muscles, muscle bracing without tooth contact, teeth contact, teeth clenching, or teeth grinding). The aim of the present study was to test the association between a single observation point self-report and EMA assessment of AB. The most frequent condition recorded by the EMA was relaxed muscles (ca. 60%) and the least frequent was teeth grinding (less than 1%). The relaxed muscle condition also showed the lowest coefficient of variance over a seven-day period of report. Additionally, only the relaxed muscles and the muscle bracing conditions presented an acceptable ability to assess AB-positive and AB-negative subjects, as defined by single-point self-report questions. The combination between self-report and EMA may have the potential to promote our ability to assess AB. We suggest to re-consider the conditions of teeth contact and teeth grinding while using EMA to evaluate AB.

Arthrocentesis of the Temporomandibular Joint: Systematic Review and Clinical Implications of Research Findings

AIMS

To review randomized clinical trials on arthrocentesis for managing temporomandibular disorders (TMD) and to discuss the clinical implications.

METHODS

On March 10, 2019, a systematic search of relevant articles published over the last 20 years was performed in PubMed, as well as in Scopus, the authors' personal libraries, and the reference lists of included articles. The focus question was: In patients with TMD (P), does TMJ arthrocentesis (I), compared to any control treatment (C), provide positive outcomes (O)?

RESULTS/CONCLUSION

Thirty papers were included comparing TMJ arthrocentesis to other treatment protocols in patients with disc displacement without reduction and/or closed lock (n = 11), TMJ arthralgia and/or unspecific internal derangements (n = 8), or TMJ osteoarthritis (n = 11). In general, the consistency of the findings was poor because of the heterogenous study designs, and so caution is required when interpreting the meta-analyses. In summary, it can be suggested that TMJ arthrocentesis improves jaw function and reduces pain levels, and the execution of multiple sessions (three to five) is superior to a single session (effect size = 1.82). Comparison studies offer inconsistent findings, with the possible exception of the finding that splints are superior in managing TMJ pain (effect size = 1.36) compared to arthrocentesis, although this conclusion is drawn from very heterogenous studies (I² = 94%). The additional use of cortisone is not effective for improving outcomes, while hyaluronic acid or platelet-rich plasma positioning may have additional value according to some studies. The type of intervention, the baseline presence of MRI effusion, and the specific Axis I diagnosis do not seem to be important predictors of effectiveness, suggesting that, as in many pain medicine fields, efforts to identify predictors of treatment outcome should focus more on the patient (eg, age, psychosocial impairment) than the disease.

Research routes on improved sleep bruxism metrics: Toward a standardised approach

A recent report from the European Sleep Research Society's task force "Beyond AHI" discussed an issue that has been a long-term subject of debate - what are the best metrics for obstructive sleep apnoea (OSA) diagnosis and treatment outcome assessments? In a similar way, sleep bruxism (SB) metrics have also been a recurrent issue for >30 years and there is still uncertainty in dentistry regarding their optimisation and clinical relevance. SB can occur alone or with comorbidities such as OSA, gastroesophageal reflux disorder, insomnia, headache, orofacial pain, periodic limb movement, rapid eye movement behaviour disorder, and sleep epilepsy. Classically, the diagnosis of SB is based on the patient's dental and medical history and clinical manifestations; electromyography is used in research and for complex cases. The emergence of new technologies, such as sensors and artificial intelligence, has opened new opportunities. The main objective of the present review is to stimulate the creation of a collaborative taskforce on SB metrics. Several examples are available in sleep medicine. The development of more homogenised metrics could improve the accuracy and refinement of SB assessment, while moving forward toward a personalised approach. It is time to develop SB metrics that are relevant to clinical outcomes and benefit patients who suffer from one or more possible negative consequences of SB.

Bruxism definition: Past, present, and future - What should a prosthodontist know?

STATEMENT OF PROBLEM

The definition of bruxism has evolved, and the dental profession needs to align with the terminologies adopted in the current literature of sleep and orofacial pain medicine.

PURPOSE

The purpose of this review was to discuss the recent evolution of bruxism concepts and the implications for changing the definition that is currently used by the prosthodontic community.

MATERIAL AND METHODS

A historical perspective on the evolution of the definition of bruxism, as well as a systematic literature review on the validity of polysomnography (PSG)-based criteria for sleep bruxism diagnosis to detect the presence of clinical consequences, is presented. Selected articles were read in a structured Population, Intervention, Comparison, Outcome (PICO) format to answer the question "If a target population with conditions such as tooth wear, dental implant complications, and temporomandibular disorders (P) is diagnosed with sleep bruxism by means of PSG (I) and compared with a population of nonbruxers (C), is the occurrence of the condition under investigation (that is, the possible pathologic consequences of sleep bruxism) be different between the 2 groups (O)?"

RESULTS

Eight studies were eligible for the review, 6 of which assessed the relationship between PSG-diagnosed sleep bruxism and temporomandibular disorder pain, while the other 2 articles evaluated the predictive value of tooth wear for ongoing PSG-diagnosed sleep bruxism and the potential role of sleep bruxism in a population of patients with failed dental implants. Findings were contradictory and not supportive of a clear-cut relationship between sleep bruxism assessed based on available PSG criteria and any clinical consequence. The literature providing definitions of bruxism as a motor behavior and not pathology has been discussed.

CONCLUSIONS

The bruxism construct has shifted from pathology to motor activity with possibly even physiological or protective relevance. An expert panel including professionals from different medical fields published 2 consecutive articles focusing on the definition of bruxism, as well as an overview article presenting the ongoing work to prepare a Standardized Tool for the Assessment of Bruxism (STAB) to reflect the current bruxism paradigm shift from pathology to behavior (that is, muscle activity). As such, dental practitioners working in the field of restorative dentistry and prosthodontics are encouraged to appraise this evolution.

Self-reported sleep bruxism among Finnish symphony orchestra musicians: Associations with perceived sleep-related problems and psychological stress

Objective: This study aimed to evaluate whether self-reported sleep bruxism among musicians is associated with sleep-related problems and/or psychological stress.Methods: Eight hundred-thirty-one Finnish orchestra musicians completed a questionnaire that covered, among others, indicators of sleep-related problems, possible sleep bruxism, and stress.Results: In total, 488 questionnaires were completed. The single variable ordinal logistic regression models revealed at least moderate associations between frequency of sleep bruxism and female gender, shorter sleep duration, longer sleep latency, problems in sleeping during concert season, feeling more often tired during the daytime, restless legs, a poor self-rated sleep quality, and more stress experience. The variables that remained in the final model were sleep duration, gender, and stress.Conclusion: Musicians who sleep 7 hours or less per night report more sleep bruxism, as compared to those who sleep 8 hours or more. Female gender and high-stress experience were associated with more sleep bruxism.

Awake bruxism frequency and psychosocial factors in college preparatory students

OBJECTIVE

To assess the frequency of reported masticatory muscles activity during wakefulness (i.e., awake bruxism [AB]), levels of anxiety, depression, stress, and the oral health-related quality of life (OHRQoL) in college preparatory students.

METHODS

Sixty-nine college preparatory students participated in the study. AB was evaluated by the Oral Behaviors Checklist (OBC) and a smartphone-based ecological momentary assessment (EMA; [Bruxapp®]). Anxiety and depression were measured by the Hospital Anxiety and Depression Scale, stress was evaluated by the Perceived Stress Scale, and OHRQoL was obtained by The Oral Health Impact Profile-14. Data were analyzed by Pearson's correlation coefficient (α = 0.05).

RESULTS

The average EMA-reported frequency of AB behaviors was 38.4%. Significant correlations were found between AB and the OBC, anxiety, depression, stress, and OHRQoL (p < 0.001).

CONCLUSION

College preparatory students demonstrated moderate frequency of AB, which was significantly correlated with psychosocial factors.

Medications and addictive substances potentially inducing or attenuating sleep bruxism and/or awake bruxism

Bruxism is a repetitive jaw‐muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. It can occur during sleep, indicated as sleep bruxism, or during wakefulness, indicated as awake bruxism. Exogenous risk indicators of sleep bruxism and/or awake bruxism are, among others, medications and addictive substances, whereas also several medications seem to have the potential to attenuate sleep bruxism and/or awake bruxism. The objective of this study was to present a narrative literature on medications and addictive substances potentially inducing or aggravating sleep bruxism and/or awake bruxism and on medications potentially attenuating sleep bruxism and/or awake bruxism. Literature reviews reporting evidence or indications for sleep bruxism and/or awake bruxism as an adverse effect of several (classes of) medications as well as some addictive substances and literature reviews on medications potentially attenuating sleep bruxism and/or awake bruxism were used as starting point and guidelines to describe the topics mentioned. Additionally, two literature searches were established on PubMed. Three types of bruxism were distinguished: sleep bruxism, awake bruxism and non‐specified bruxism. Generally, there are insufficient evidence‐based data to draw definite conclusions concerning medications and addictive substances inducing or aggravating sleep bruxism and/or awake bruxism as well as concerning medications attenuating sleep bruxism and/or awake bruxism. There are insufficient evidence‐based data to draw definite conclusions concerning medications and addictive substances inducing or aggravating sleep bruxism and/or awake bruxism as well as concerning medications attenuating sleep bruxism and/or awake bruxism.

Relationship between self-reported bruxism and periodontal status: Findings from a cross-sectional study

BACKGROUND

Several studies seek to prove the relationship between bruxism and periodontal status although it remains unclear and debatable. We aimed to assess the association between self-reported (SR) bruxism with the periodontal status in a large scale survey.

METHODS

A total of 1064 individuals from the southern region of the Lisbon Metropolitan Area (Portugal) were enrolled. Patients were interviewed for the SR bruxism assessment through a self-report questionnaire. Full-mouth periodontal status was assessed with probing depth (PD), clinical attachment loss (CAL), gingival recession (REC), and bleeding on probing (BoP) being measured. The American Association of Periodontology/European Federation of Periodontology 2018 case definitions were used. Logistic regression analyses provided information on the influence of SR bruxism towards periodontitis.

RESULTS

SR bruxers exhibited lower prevalence of periodontitis. Additionally, SR bruxers with periodontitis had PD and CAL significantly lower than patients with only periodontitis. Multivariate analysis suggests that SR bruxism was significantly associated with a lower risk of periodontitis (odds ratio [OR] = 0.42 95% CI: 0.32-0.56). Mean PD and CAL were significantly lower in SR bruxers. When assessing the type of SR bruxism, significant differences among mean PD, CAL, and BoP levels were also identified.

CONCLUSION

SR bruxism and periodontal status are negatively associated. SR bruxers exhibit lower odds towards periodontitis and better periodontal clinical characteristics. Further studies are mandatory to clarify these findings.

Efficacy and Safety of Botulinum Toxin Type A on Persistent Myofascial Pain: A Randomized Clinical Trial

This study assessed the safety and efficacy of three different doses of BoNT-A for persistent myofascial pain (MFP). One hundred female subjects were randomly assigned into five groups (n = 20): oral appliance (OA), saline solution (SS) and three BoNT-A groups with different doses. Pain intensity and pressure pain threshold were evaluated up to 24 weeks after treatment. Adverse effects related to muscle contraction, masticatory performance, muscle thickness and mandibular bone volume were also assessed. Changes over time were compared within and between groups. The “nparLD” package and Wilcoxon signed-rank test were used to analyze the data. BoNT-A reduced pain intensity (p < 0.0001) and increased pressure pain threshold (p < 0.0001) for up to 24 weeks compared to the placebo. No differences were found between BoNT-A and OA at the last follow-up. A transient decline in masticatory performance (p < 0.05) and muscle contraction (p < 0.0001), and a decrease in muscle thickness (p < 0.05) and coronoid and condylar process bone volume (p < 0.05) were found as dose-related adverse effects of BoNT-A. Regardless of the dose, BoNT-A was as effective as OA on MFP. Notwithstanding, due to BoNT-A dose-related adverse effects, we suggest the use of low doses of BoNT-A in MFP patients that do not benefit from conservative treatments.

Pain Predictors in a Population of Temporomandibular Disorders Patients

The aim of the present study was to assess the potential role of some biological, psychological, and social factors to predict the presence of painful temporomandibular disorders (TMDs) in a TMD-patient population. The study sample consisted of 109 consecutive adult patients (81.7% females; mean age 33.2 ± 14.7 years) who were split into two groups based on Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) diagnoses: painful TMD and non-painful TMD. The presence of pain was adopted as the depended variable to be identified by the following independent variables (i.e., predictors): age, gender, bruxism, tooth wear, chewing gum, nail biting, perceived stress level, chronic pain-related impairment (GCPS), depression (DEP), and somatization (SOM). Single-variable logistic regression analysis showed a significant relationship between TMD pain and DEP with an odds ratio of 2.9. Building up a multiple variable model did not contribute to increase the predictive value of a TMD pain model related to the presence of depression. Findings from the present study supported the existence of a relationship between pain and depression in painful TMD patients. In the future, study designs should be improved by the adoption of the best available assessment approaches for each factor.

Correlation Between Sleep-Time Masseter Muscle Activity and Tooth Wear: An Electromyographic Study

AIMS

To assess the correlation between tooth wear and sleep-time masseter muscle activity (sMMA) in a group of healthy young adults who underwent home electromyographic/electrocardiographic (EMG/ECG) recordings with a portable device.

METHODS

A total of 41 healthy volunteers (23 women, 18 men; mean age 28.8 years, range 25 to 40) with good natural dentition underwent a 2-night in-home evaluation with a portable device that allowed a simultaneous sleep-time recording of EMG signals from both masseter muscles and heart rate. The number of sleep bruxism (SB) episodes per sleep hour (SB index), the number of phasic, tonic, and mixed sMMA events per hour, and the total number of sMMA events per night were calculated. All individuals also underwent an assessment of tooth wear on digital casts with the adoption of a six-degree rating scale. Correlations between sMMA variables and tooth wear were assessed using Pearson test. The null hypothesis was that correlation between the two conditions would not be significant.

RESULTS

On average, the SB index was 4.5 ± 2.6, while the total number of sleep-time masseter contractions was 97.2 ± 55.2. Of those contractions, almost 60% were phasic. Average tooth wear was 1.5 ± 0.7, with the canines and mandibular incisors showing the highest wear scores. For all pairwise analyses, correlation values were not significant (P values .11 to .69), with r values ranging from 0.064 to 0.253.

CONCLUSION

The null hypothesis of an absence of correlation between tooth wear and sMMA could not be rejected, implying that tooth wear cannot be used as an indicator of ongoing SB or sMMA. Future studies taking into account the multifaceted nature of tooth wear and the complex natural course of sleep phenomena are encouraged to investigate the issue further, at the individual level.