Is bruxism severity a predictor of oral splint efficacy in patients with myofascial face pain?

Grit your teeth and chew your food: Implications of food material properties and abrasives for rates of dental microwear formation in laboratory Sapajus apella (Primates)

Dental microwear analysis has been employed in studies of a wide range of modern and fossil animals, yielding insights into the biology/ecology of those taxa. Some researchers have suggested that dental microwear patterns ultimately relate back to the material properties of the foods being consumed, whereas others have suggested that, because exogenous grit is harder than organic materials in food, grit should have an overwhelming impact on dental microwear patterns. To shed light on this issue, laboratory-based feeding experiments were conducted on tufted capuchin monkeys [Sapajus apella] with dental impressions taken before and after consumption of different artificial foods. The foods were (1) brittle custom-made biscuits laced with either of two differently-sized aluminum silicate abrasives, and (2) ductile custom-made "gummies" laced with either of the two same abrasives. In both cases, animals were allowed to feed on the foods for 36 hours before follow-up dental impressions were taken. Resultant casts were analyzed using a scanning electron microscope. We asked five questions: (1) would the animals consume different amounts of each food item, (2) what types of dental microwear would be formed, (3) would rates of dental microwear differ between the consumption of biscuits (i.e., brittle) versus gummies (i.e., ductile), (4) would rates of dental microwear differ between foods including larger- versus smaller-grained abrasives, and (5) would rates of dental microwear differ between molar shearing and crushing facets in the animals in these experiments? Results indicated that (1) fewer biscuits were consumed when laced with larger-grained abrasives (as opposed to smaller-grained abrasives), but no such difference was observed in the consumption of gummies, (2) in all cases, a variety of dental microwear features was formed, (3) rates of dental microwear were higher when biscuits versus gummies were consumed, (4) biscuits laced with larger-grained abrasives caused a higher percentage of new features per item consumed, and (5) the only difference between facets occurred with the processing of biscuits, where crushing facets showed a faster rate of wear than shearing facets. These findings suggest that the impact of exogenous grit on dental microwear is the result of a dynamic, complex interaction between (at the very least) grit size, food material properties, and time spent feeding - which is further evidence of the multifactorial nature of dental microwear formation.

Optimal application of compressive palatal stents following mesiodens removal in pediatric patients: A Randomized Controlled Trial

Background

There is no scientific evidence supporting the choice of a palatal stent in patients who underwent removal of an impacted supernumerary tooth. We aimed to investigate the effects of palatal stents in patients who underwent supernumerary tooth removal through a palatal approach and to suggest the optimal stent thickness and material.

Material and Methods

We recruited 144 patients who underwent extraction of a supernumerary tooth between the maxillary anterior teeth. Subjects were assigned to a control group (CG) or one of four compressive palatal stent groups (CPSGs) classified by the thickness and material of the thermoplastic acrylic stent used. Palatal gingival swelling and objective indices (healing, oral hygiene, gingival, and plaque) were evaluated before surgery and on postoperative days (PODs) 3, 7, and 14; pain/discomfort and the Child Oral Health Impact Profile (COHIP) were assessed as subjective indices of the effects of the stent.

Results

The CPSGs showed faster healing than did the CG on PODs 7 (P<0.001) and 14 (P=0.043); swelling was measured by 1.64±0.88 mm and 4.52±0.39 mm, respectively. Although swelling was least in the 4-mm hard group (0.92±0.33 mm), the difference compared with that in the 2-mm hard group (1.01±0.18 mm) was not significant (P=0.077). The CPSGs showed better COHIP (P<0.001-0.036) and pain scores (P<0.001) than did the CG on PODs 1-3.

Conclusions

Compressive palatal stents reduce discomfort by decreasing pain and alleviating swelling. Although a stent is effective regardless of its thickness and material, 2-mm hard stents maximized such positive effects with minimal discomfort.

Key words:Supernumerary tooth, tooth Extraction, postoperative care, oral Health, pediatric dentistry.

The efficacy of occlusal splints in the treatment of bruxism: A systematic review

OBJECTIVES

Bruxism is a commonly reported oral parafunctional activity characterised by excessive tooth grinding or clenching outside normal functional activity. The present systematic review aims to examine the available literature to determine the effectiveness of occlusal splints in the treatment of bruxism compared to no treatment and alternative treatment modalities.

DATA

Data extraction was undertaken in conjunction with quality of evidence assessment.

SOURCES

A literature search of the following databases was undertaken: MEDLINE via OVID, Pubmed (Medline), Cochrane Oral Health Group's Trials, The Cochrane Central Register of Controlled Trials and EMBASE.

STUDY SELECTION

Randomised Controlled Trials (RCT) and quasi-RCTs which met the inclusion criteria were selected for analysis. These included studies comparing occlusal splints to no treatment or other interventions.

RESULTS

Twenty-two studies were identified for review with fourteen meeting the inclusion criteria. Only a small number of studies were available in each comparison (one or two for some) all of which had a medium to high risk of bias.

CONCLUSIONS

There is insufficient evidence to determine whether occlusal splint therapy for the treatment of bruxism provides a benefit over no treatment, other oral appliances, TENS, behavioural or pharmacological therapy. Furthermore, there is a lack of studies in each comparison with many suffering from a high risk of bias. There is a need for further research in this area and improvement in trial quality.

CLINICAL SIGNIFICANCE STATEMENT

This systematic review aimed to determine the effectiveness of occlusal splints in the treatment of bruxism. It found there was insufficient evidence to recommend occlusal splint therapy over no treatment or other treatment modalities. This is relevant to dental clinicians who may provide such appliances and cautions them in treatment provision.

Bruxism: Best Evidence Consensus Statement

PURPOSE

The purpose of this Best Evidence Consensus Statement is to report on the prevalence, potential causes or association, treatment and cure of bruxism.

MATERIALS AND METHODS

A literature search limited to Clinical Trials, Randomized Controlled Trials, Systematic Reviews and Meta Analyses, with the key words bruxism, and prevalence identified 22 references, bruxism and causation 21, bruxism, and treatment 117, and bruxism and cure none.

RESULTS

Prevalence received 5 references which were relevant to the question researched. Causation received 11 relevant references, treatment 34 relevant references and cure none. Eighteen additional references were culled from the reference lists in the aforementioned articles.

CONCLUSIONS

Due to variations in demographics and the dependence on anamnestic data, the true prevalence of bruxism in any specific population is unknown. There is moderate evidence that psychosocial factors such as stress, mood, distress, nervousness, and feeling blue are associated with sleep bruxism (SB) as well as caffeine, alcohol, and smoking. There is no consensus on what symptoms of SB or awake bruxism (AB) should be treated. There is some evidence that occlusal devices and bio feedback therapies can be utilized in SB treatment. There is conflicting evidence in the use of Botulinum toxin A and no compelling evidence for the use of drug therapy to treat SB. There is not an established cure for bruxism. The clinician is best served in using caution in the dental rehabilitation of patients with severe occlusal wear.

Applying dental microwear texture analysis to the living: Challenges and prospects

OBJECTIVES

The food that people and animals consume leaves microscopic traces on teeth in predictable ways, and analyses of these markings-known as dental microwear analyses-allow us to reverse engineer the characteristics of diet. However, the microwear features of modern human diets are most often interpreted through the lens of ethnographic records. Given the subtle variation within human diets when compared to other species, we need better models of how foods and processing techniques produce marks on teeth. Here, we report on the second study to target the occlusal surface microwear of living human populations, and the first to target populations other than foragers.

METHODS

We collected 150 dental impressions from five Kenyan communities: El Molo, Turkana (Kerio), Luhya (Webuye), Luhya (Port Victoria), and Luo (Port Victoria), representing a range of subsistence strategies and associated staple diets-fishing, pastoralism, and agriculture. Our results suggest that the occlusal microwear of these groups records differences in diet. However, biofilm obscured most of the molds obtained despite the steps taken to remove it, resulting in only 38 usable surfaces.

RESULTS

Due to the biofilm problem and final sample size, the analysis did not have enough power to demonstrate the differences observed statistically. The results and problems encountered are here explained.

CONCLUSIONS

Considering that in vivo studies of dental microwear texture analysis have the potential to increase our understanding of the association between patterns of dental microwear and complex, mixed human diets, resolution of the current pitfalls of the technique is critical.

Interventions to reduce bruxism in children and adolescents: a systematic scoping review and critical reflection

The aim of the present study was to perform a critical reflection about intervention options for bruxism reduction in children and adolescents. Search was conducted based on the PICO-structured question: "What are the intervention options to reduce bruxism in children/adolescents?". No language, year, or study design restrictions were imposed. Studies reporting interventions to reduce bruxism in children (< 10) and adolescents (10 to 19 years old) were included. Reviews and letters to editors were not included. From 2723 records, 17 papers were included. Included studies were primarily randomized clinical trials performed in Brazil (35.3%) and using different criteria for the diagnosis of bruxism. Reduction in self-reported bruxism and headaches associated with bruxism were observed in studies that used medications (hydroxyzine/trazodone/flurazepam), occlusal splints, orthodontic interventions, and psychological and physical therapy interventions. Reduction in Rhythmic Masticatory Muscle Activity was observed with the use of the occlusal splint and in orthodontic interventions. Alternative treatments (medicinal extracts such as Melissa officinalis-L) have shown inconclusive results.Conclusions: Several intervention options are available to inhibit or reduce bruxism activity. The respective indication, contraindications, and side effects of each treatment option must be assessed individually and carefully, taking into account that bruxism is not considered a disorder in otherwise healthy individuals.What is known• Biological and psychological factors have been strongly correlated to the development of bruxism• Bruxism prevalence ranging from 6 to 50% in childrenWhat is new• Reduction in self-reported bruxism and headaches associated with bruxism were observed in studies that used medication (Hydroxyzine/ Trazodone/ Flurazepam), occlusal splints, orthodontic interventions, psychological, and physical therapy interventions• A reduction in Rhythmic Masticatory Muscle Activity was observed with the use of the occlusal splint and orthodontic interventions. Alternative treatments (medicinal extracts such as Melissa officinalis L) show inconclusive results in respect of the reduction in bruxism.

The dental microwear of hard-object feeding in laboratory Sapajus apella and its implications for dental microwear formation

OBJECTIVES

This study seeks to determine if (a) consumption of hard food items or a mixture of food items leads to the formation of premolar or molar microwear in laboratory capuchin monkeys (Sapajus apella) in one feeding session and (b) rates of microwear formation are associated with the number of food items consumed.

MATERIALS AND METHODS

Five adult male capuchins were used in two experiments, one where they were fed unshelled Brazil nuts, and the other where they were fed a mixture of food items. Dental impressions were taken before and after each feeding session. Epoxy casts made from those impressions then were used in SEM analyses of rates of microwear formation. Upper and lower premolars and molars were analyzed. Qualitative comparisons were made and Spearman's rank-order correlations used to examine the relationship between rates of microwear formation and number of Brazil nuts consumed.

RESULTS

Premolars and molars generally showed new microwear in the form of pits and scratches. However, the incidence of those features was low (0-6%). Rates of microwear formation were highest during the consumption of Brazil nuts.

DISCUSSION

Variations in the rate of microwear formation on the premolars likely reflected patterns of ingestion whereas consistency in the rate of microwear on the molars likely reflected patterns of chewing. While dental microwear formation seemed to be correlated with the number of hard objects consumed, rates did differ between individuals. Differences in results between the two experiments demonstrate some of the limitations in our knowledge of dental microwear formation.

Soft versus hard occlusal splint therapy in the management of temporomandibular disorders (TMDs)

Aim

To compare between soft and hard occlusal splint therapy for the management of myofacial pain dysfunction (MPD) or internal derangement (ID) of the temporomandibular joint (TMJ) with reciprocal clicking.

Patients and methods

This study included 50 patients (age range: 24–47 years) who had been diagnosed with MPD or ID of the TMJ in the form of reciprocal clicking. Patients were divided into two groups. They were treated for 4 months with either a vacuum-formed soft occlusal splint constructed from 2-mm-thick elastic rubber sheets (soft splint group) or a hard flat occlusal splint fabricated from transparent acrylic resin (hard splint group). Monthly follow-up visits were performed during the treatment period. Before treatment and 1, 2, 3 and 4 months after treatment, the dentist measured all parameters of TMJ function (pain visual analog scores, tenderness of masticatory muscles, clicking and tenderness of the TMJ, and range of mouth opening).

Results

All parameters of TMJ function showed significant improvement in both groups during the follow-up period, with a statistically significant difference between the two groups at the 4-month follow-up visit.

Conclusions

Both forms of occlusal splints (soft and hard) improved TMJ symptoms in patients with MPD or ID of the TMJ. However, the soft occlusal splints exhibited superior results after 4 months of use.

GABA and glutamate levels in occlusal splint-wearing males with possible bruxism

OBJECTIVE

The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in the pathophysiology of anxiety behavioural disorders such as panic disorder and post-traumatic stress disorder and is also implicated in the manifestation of tooth-grinding and clenching behaviours generally known as bruxism. In order to test whether the stress-related behaviours of tooth-grinding and clenching share similar underlying mechanisms involving GABA and other metabolites as do anxiety-related behavioural disorders, we performed a Magnetic Resonance Spectroscopy (MRS) study for accurate, in vivo metabolite quantification in anxiety-related brain regions.

DESIGN

MRS was performed in the right hippocampus and right thalamus involved in the hypothalamic-pituitary-adrenal axis system, together with a motor planning region (dorsal anterior cingulate cortex/pre-supplementary motor area) and right dorsolateral prefrontal cortex (DLPFC). Eight occlusal splint-wearing men (OCS) with possible tooth-grinding and clenching behaviours and nine male controls (CON) with no such behaviour were studied.

RESULTS

Repeated-measures ANOVA showed significant Group×Region interaction for GABA+ (p = 0.001) and glutamate (Glu) (p = 0.031). Between-group post hoc ANOVA showed significantly lower levels of GABA+ (p = 0.003) and higher levels of Glu (p = 0.002) in DLPFC of OCS subjects. These GABA+ and Glu group differences remained significant (GABA+, p = 0.049; Glu, p = 0.039) after the inclusion of anxiety as a covariate. Additionally, GABA and Glu levels in the DLPFC of all subjects were negatively related (Pearson's r = -0.75, p = 0.003).

CONCLUSIONS

These findings indicate that the oral behaviours of tooth-grinding and clenching, generally known as bruxism, may be associated with disturbances in brain GABAergic and glutamatergic systems.

Comparative evaluation of the efficacy of occlusal splints fabricated in centric relation or maximum intercuspation in temporomandibular disorders patients

Fabrication of occlusal splints in centric relation for temporomandibular disorders (TMD) patients is arguable, since this position has been defined for asymptomatic stomatognathic system. Thus, maximum intercuspation might be employed in patients with occlusal stability, eliminating the need for interocclusal records. This study compared occlusal splints fabricated in centric relation and maximum intercuspation in muscle pain reduction of TMD patients. Twenty patients with TMD of myogenous origin and bruxism were divided into 2 groups treated with splints in maximum intercuspation (I) or centric relation (II). Clinical, electrognathographic and electromyographic examinations were performed before and 3 months after therapy. Data were analyzed by the Student's t test. Differences at 5% level of probability were considered statistically significant. There was a remarkable reduction in pain symptomatology, without statistically significant differences (p>0.05) between the groups. There was mandibular repositioning during therapy, as demonstrated by the change in occlusal contacts on the splints. Electrognathographic examination demonstrated a significant increase in maximum left lateral movement for group I and right lateral movement for group II (p<0.05). There were no significant differences (p>0.05) in the electromyographic activities at rest after utilization of both splints. In conclusion, both occlusal splints were effective for pain control and presented similar action. The results suggest that maximum intercuspation may be used for fabrication of occlusal splints in patients with occlusal stability without large discrepancies between centric relation and maximum intercuspation. Moreover, this technique is simpler and less expensive.

Temporomandibular joint: disorders, treatments, and biomechanics

Temporomandibular joint (TMJ) is a complex, sensitive, and highly mobile joint. Millions of people suffer from temporomandibular disorders (TMD) in USA alone. The TMD treatment options need to be looked at more fully to assess possible improvement of the available options and introduction of novel techniques. As reconstruction with either partial or total joint prosthesis is the potential treatment option in certain TMD conditions, it is essential to study outcomes of the FDA approved TMJ implants in a controlled comparative manner. Evaluating the kinetics and kinematics of the TMJ enables the understanding of structure and function of normal and diseased TMJ to predict changes due to alterations, and to propose more efficient methods of treatment. Although many researchers have conducted biomechanical analysis of the TMJ, many of the methods have certain limitations. Therefore, a more comprehensive analysis is necessary for better understanding of different movements and resulting forces and stresses in the joint components. This article provides the results of a state-of-the-art investigation of the TMJ anatomy, TMD, treatment options, a review of the FDA approved TMJ prosthetic devices, and the TMJ biomechanics.

Occlusal splints for treating sleep bruxism (tooth grinding)

BACKGROUND

Sleep bruxism is an oral activity characterised by teeth grinding or clenching during sleep. Several treatments for sleep bruxism have been proposed such as pharmacological, psychological, and dental.

OBJECTIVES

To evaluate the effectiveness of occlusal splints for the treatment of sleep bruxism with alternative interventions, placebo or no treatment.

SEARCH STRATEGY

We searched the Cochrane Oral Health Group's Trials Register (to May 2007); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 1); MEDLINE (1966 to May 2007); EMBASE (1980 to May 2007); LILACS (1982 to May 2007); Biblioteca Brasileira de Odontologia (1982 to May 2007); Dissertation, Theses and Abstracts (1981 to May 2007); and handsearched abstracts of particular importance to this review. Additional reports were identified from the reference lists of retrieved reports and from article reviews about treating sleep bruxism. There were no language restrictions.

SELECTION CRITERIA

We selected randomised or quasi-randomised controlled trials (RCTs), in which splint therapy was compared concurrently to no treatment, other occlusal appliances, or any other intervention in participants with sleep bruxism.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out independently and in duplicate. Validity assessment of the included trials was carried out at the same time as data extraction. Discrepancies were discussed and a third review author consulted. The author of the primary study was contacted when necessary.

MAIN RESULTS

Thirty-two potentially relevant RCTs were identified. Twenty-four trials were excluded. Five RCTs were included. Occlusal splint was compared to: palatal splint, mandibular advancement device, transcutaneous electric nerve stimulation, and no treatment. There was just one common outcome (arousal index) which was combined in a meta-analysis. No statistically significant differences between the occlusal splint and control groups were found in the meta-analyses.

AUTHORS' CONCLUSIONS

There is not sufficient evidence to state that the occlusal splint is effective for treating sleep bruxism. Indication of its use is questionable with regard to sleep outcomes, but it may be that there is some benefit with regard to tooth wear. This systematic review suggests the need for further investigation in more controlled RCTs that pay attention to method of allocation, outcome assessment, large sample size, and sufficient duration of follow up. The study design must be parallel, in order to eliminate the bias provided by studies of cross-over type. A standardisation of the outcomes of the treatment of sleep bruxism should be established in the RCTs.

Effects of an occlusal splint compared with cognitive-behavioral treatment on sleep bruxism activity

The impact of an occlusal splint (OS) compared with cognitive-behavioral treatment (CBT) on the management of sleep bruxism (SB) has been poorly investigated. The aim of this study was to evaluate the efficacy of an OS with CBT in SB patients. Following a randomized assignment, the OS group consisted of 29, and the CBT group of 28, SB patients. The CBT comprised problem-solving, progressive muscle relaxation, nocturnal biofeedback, and training of recreation and enjoyment. The treatment took place over a period of 12 wk, and the OS group received an OS over the same time period. Both groups were examined pretreatment, post-treatment, and at 6 months of follow-up for SB activity, self-assessment of SB activity and associated symptoms, psychological impairment, and individual stress-coping strategies. The analyses demonstrated a significant reduction in SB activity, self-assessment of SB activity, and psychological impairment, as well as an increase of positive stress-coping strategies in both groups. However, the effects were small and no group-specific differences were seen in any dependent variable. This is an initial attempt to compare CBT and OS in SB patients, and the data collected substantiate the need for further controlled evaluations, using a three-group randomized design with repeated measures to verify treatment effects.

Clinical comparison between two different splint designs for temporomandibular disorder therapy

OBJECTIVE

To compare splint therapy in temporomandibular disorder (TMD) patients using two splint designs.

MATERIAL AND METHODS

In a double-blind randomized parallel trial, 40 consenting patients were selected from the dental faculty pool of TMD patients. Two splint designs were produced: an ordinary stabilization (Michigan type) and a NTI (Nociceptiv trigeminal inhibition). The differences in splint design were not described to the patients. All patients were treated by one operator. A separate, blinded, examiner assessed joint and muscle tenderness by palpation and jaw opening prior to splint therapy, and after 2 and 6 weeks' and 3 months' splint use during night-time. The patients reported headache and TMD-related pain on a visual analog scale before and after splint use, and were asked to describe the comfort of the splint and invited to comment.

RESULTS

Thirty-eight patients with mainly myogenic problems were observed over 3 months. A reduction of muscle tenderness upon palpation and self-reported TMD-related pain and headache and an improved jaw opening was seen in both splint groups (p < 0.05; paired t-test and Wilcoxon signed-ranks tests). There were no changes for TM joint tenderness upon palpation. No differences were noted between the two splint designs after 3 months for the chosen criteria of treatment efficacy (p > 0.05; Mann-Whitney U-test).

CONCLUSION

No differences in treatment efficacy were noted between the Michigan and the NTI splint types when compared over 3 months.