Occlusion and splint therapy

Occlusal splints-types and effectiveness in temporomandibular disorder management

Background

Occlusal splints are routinely used in dental offices to diagnose and treat abnormalities of the masticatory system. There are different occlusal splints, each of which can address various conditions. They may treat individuals with temporomandibular disorders (TMDs) and bruxism or be used for occlusal stabilization and dentition wear reduction.

Methods

The literature in the National Library of Medicine's Medline Database was reviewed using the Mesh terms 'occlusal splints' AND 'Temporomandibular Disorders.

Conclusion

Occlusal splints can treat a wide variety of TMDs. They can treat bruxism, headaches, postural imbalances related to TMDs, and decreased vertical dimension of occlusion (VDO). However, there is no clear evidence that occlusal splints are superior to physiotherapy in treating TMDs. In the long-term follow-up, they were equally effective as other therapies.

Effect of different storage conditions on the fit of 3D-printed occlusal devices used to treat temporomandibular disorders

STATEMENT OF PROBLEM

Research-based storage guidelines for 3-dimensional (3D)-printed occlusal devices are lacking.

PURPOSE

The purpose of this in vitro study was to investigate the dimensional stability of the internal surface of 3D-printed occlusal devices under different storage conditions.

MATERIAL AND METHODS

Maxillary and mandibular dental casts were scanned and exported to a 3D printer to fabricate 30 occlusal devices. The specimens were stored under 3 different conditions (n=10): air dried and stored under natural light (group DL), stored in a dark container with water (group W), and air dried and stored in a dark container (group D). The intaglio surfaces of the occlusal devices were scanned by a laboratory scanner at 4 time points: immediately after polymerization (t₀, control), after 1 day (t₁), after 7 days (t₂), and after 27 days (t₃). The dimensional changes of the fitting surfaces between t₀ and t₁ (Δt₁), t₀ and t₂ (Δt₂), and t₀ and t₃ (Δt₃) were measured by using best fit alignment in a surface analysis software program. In addition, comparisons were made between the posterior and anterior sections. Statistical analysis was completed with Kolmogorov-Smirnov, 1-way ANOVA, Friedman, Kruskal-Wallis, Mann-Whitney, and unpaired t tests.

RESULTS

The root mean square (RMS) of group DL between Δt₁ and Δt₂ (P=.002) and between Δt₁ and Δt₃ (P=.002) showed a statistically significant difference. The RMS of group W between Δt₁ and Δt₃ (P=.008) showed a statistically significant difference. When the groups were compared with each other at the different time points, the DL group showed a statistically significant difference compared with groups W and D at Δt₁. The examination of different areas of the occlusal device (right molar, incisor, and left molar sites) indicated no statistically significant differences in RMS among all groups (P>.05).

CONCLUSIONS

The occlusal devices of group DL showed the least dimensional change of the fitting surface for Δt₁ in comparison with group W and D, while no statistically significant differences were found among the groups for Δt₂ and Δt₃. In terms of the different locations, no statistically significant differences were found among the 3 locations for any given group after 27 days.

Are occlusal splints effective in reducing myofascial pain in patients with muscle-related temporomandibular disorders? A randomized-controlled trial

Objectives

This study aims to evaluate the effectiveness of upper Michigan occlusal splint (OS) compared to mandibular OS in terms of pain, range of motion (ROM), and muscle activity as assessed by surface electromyography (sEMG) in patients affected by muscle-related temporomandibular disorders (TMD).

Patients and methods

In this randomized-controlled trial, a total of 40 adult patients (13 males, 27 females; mean age: 47.2±12.8 years; range, 22 to 56 years) with a diagnosis of myofascial pain, lasting from at least three months on at least one masseter muscle. The patients were randomly allocated into two groups: Group 1 (n=20) using upper Michigan OS and Group 2 (n=20) using mandibular OS. At baseline (T0), at one (T1), three (T2), and six months (T3), the following outcomes were assessed: myofascial pain by Visual Analog Scale (VAS) and ROM of mandible movements, activity of the main masticatory muscles through sEMG.

Results

There were no significant intra-group differences in the outcome measures assessed in both groups. However, Group 2 had a significantly higher right lateral mandibular ROM at T2 (7.1±3.1 vs. 9.8±2.3, respectively; p<0.05) and a significantly higher left lateral mandibular ROM at T3 (7.6±3.5 vs. 10.5±2.1, respectively; p<0.05). We found no significant difference in none of the sEMG parameters.

Conclusion

Our study results suggest that OS, independently from being built on the upper or lower arch, seems to not have significant effects in reducing pain over a six-month period in TMD patients.

Reproducibility of the Obtained Centric Relation Records in Patients with Disc Displacement with Reduction

Objective

The aim of this study was to investigate reproducibility of the position of centric relation in patients with disc displacement with reduction.

Materials and methods

The test group included 30 subjects, diagnosed with disc displacement with reduction in right, left or both joints. The control group included 12 individuals with no signs and symptoms of temporomandibular disorders. Using chin point guidance with a jig, centric relation record was made three times by every participant, in a single session. Left and right condylar position for each centric relation record was determined and recorded using the electronic ultrasonic measuring device. The data were transferred to the computer, processed and analyzed. Condylar distances between centric relation records were measured (anteroposterior, vertical, transversal and linear values), and the data were statistically analyzed using the t and the F tests.

Results

No statically significant difference was found between the test and the control groups. Two thirds of study participants demonstrated condylar position of the repeated centric relation recording within the area of 0.3 mm in diameter. For more than 90% of participants that area was within 0.4 mm.

Conclusions

There is no difference in reproducibility of the centric relation between patients with disc displacement with reduction and healthy temporomandibular joint individuals (p>0.05). When doing centric relation record on a patient with disc displacement with reduction there is no need for previous splint therapy and standard precautions are acceptable. The obtained results must be interpreted within the experimental group, and not projected on the other groups of temporomandibular disorders.

The management of tooth wear with crowns and indirect restorations

This manuscript summarises the reasons behind choosing indirect restorations in the treatment of tooth wear. The purpose of this article is to discuss the use of crowns as a restorative treatment option for tooth wear. There are also challenges with the use of composites as they can repeatedly fail and in these situations the indications for crowns for treatment of tooth wear is worthy of consideration. This article is part of a themed issue discussing the management of tooth wear.

Prevention and Management of Tooth Wear: The Role of Dental Technology

Tooth wear is a multifactorial condition and the term is used to describe all types of non-carious tooth substance loss: abrasion (produced by interaction between the teeth and other substances), attrition (produced during tooth-to-tooth contact), erosion (produced by a chemical process) and abfraction (produced through abnormal occlusal loading that predisposes tooth substance to mechanical and chemical wear). Dental technology has an important role in preventing, managing and monitoring tooth wear in a variety of ways. Hard poly(methyl methacrylate) or soft ethylene-vinyl acetate splints can be prescribed to alleviate bruxism, the most common cause of attrition. Thermoformed appliances can be used for the application of products that reduce dental erosion such as fluoride gel. Patients with significant tooth surface loss may require laboratory-made restorations, as well as removable appliances with bite planes that generate inter-occlusal space to facilitate restorations, or surgical templates to provide guidance in preparing restorations for those requiring surgical crown lengthening. Dental study models and digitised models can also prove valuable in terms of monitoring the condition. This paper presents a review of the role that dental technology plays in tooth wear prevention, management and monitoring.

Aesthetic Treatment Related to Clinical Need--An Illustrated Case Report

Aesthetic treatment may be patient driven and usually by a 'want', rather than a 'need'. This paper describes the management of a patient who presented with aesthetic wants and clinical needs, both of which were caused as a result of unsuccessful aesthetic treatment which the patient had received previously. The diagnostic process, discussion of the treatment plan and clinical procedures, which produced a satisfactory result, are described and illustrated. Clinical Relevance: This case demonstrates that aesthetic treatment may commit the patient to future dental treatment needs, particularly if treatment provided is poorly planned and carried out to an unsatisfactory standard.

Occlusal stabilization appliance: evaluation of its efficacy in the treatment of temporomandibular disorders

Occlusal stabilization appliances or splints are the most widely employed method for treatment of temporomandibular disorders (TMD). Magnetic Resonance Imaging (MRI) is the most indicated imaging modality to evaluate the components of the temporomandibular joint (TMJ). Forty patients with signs and symptoms of temporomandibular disorders were treated with splints for a mean period of 12 months, comprising regular semimonthly follow-ups. After stabilization of the clinical status, occlusal adjustments and MRI evaluation were performed. It was concluded that the success of this kind of treatment are related to the total (70%) or partial improvement (22.5%) of painful symptomatology and to the functional reestablishment of the craniomandibular complex. The MRI allowed evaluation and also the conclusion that the splints provide conditions for the organism to develop means to resist to the temporomandibular disorders by means of elimination of several etiologic factors. Moreover, after treatment the patients are able to cope with disc displacements with larger or smaller tolerance.

Effect of occlusal splint therapy on maximum bite force in individuals with moderate to severe attrition of teeth

OBJECTIVE

The purpose of the pilot study was to determine the effect of restoring lost occlusal vertical dimension (OVD) due to attrition on maximum bite force in humans.

METHODOLOGY

A total of 124 subjects in age range of 25-40 years, with moderate to severe attrition, having full complement of teeth were screened according to inclusion and exclusion criteria. After consent, occlusal vertical dimension was assessed by employing mechanical and physiological methods in the experimental group and a maxillary canine guided hard splint was fabricated for each subjects fulfilling inclusion criteria and with positive consent (78). Bite force in experimental group was measured before, immediately after delivery of splint and subsequently at an interval of four, eight, and twelve weeks. Due loss during follow up, only 50 subjects could be available for bite force recording till 12 weeks. Bite force of age, gender, height and weight matched controls with no signs of attrition was also measured for comparison.

RESULTS

Bite force of the experimental group was found to be significantly less than the matched controls (P=0.000) initially. After delivery of splint, bite force values increased progressively till twelve weeks. However comparison of bite force values of experimental group with control group showed no significant difference at end of eight (P=0.008) and twelve weeks (P=0.162).

CONCLUSION

It was concluded that maximum bite force increases with restoration of lost vertical using splint therapy. A time period of 8-12 weeks is required to restore the maximum bite force value approximately similar to matched controls.

Patient responses to vacuum formed splints compared to heat cured acrylic splints: pilot study

OBJECTIVE

Vacuum formed and heat cured acrylic splints have been used in the diagnosis and treatment of temporomandibular disorders. The aim of this study was to evaluate patient's preference to either the vacuum formed or the heat cured acrylic splint.

MATERIAL AND METHODS

Twenty patients planned to receive splints were chosen from the dental school. Both types of occlusal splints were fabricated for each of them. Each patient used the splints alternatively on a nightly basis for 3 weeks. After 3 weeks, each patient completed a questionnaire regarding the comfort, fit, retention, occlusal contact, taste, gingival and lip irritation, smoothness and smelling. Statistical analysis was conducted by the MacNemar's Chisquare test.

RESULTS

There was no statistical difference in patient's responses to the different splint materials except for the comfort of wearing through the night.

CONCLUSION

The vacuum formed and heat cured acrylic splint may be equally worn in patient preference for treatment of temporomandibular disorders.

[Occlusal splint: state of the art]

Occlusal splint are defined as intra-oral devices mostly indicated to modify the occlusal relationship between maxillar and mandibular dental arches. Among the different shapes of occlusal splint, an updating seemed necessary to the authors. The main indications for occlusal splint are represented by temporomandibular disorders and teeth protection. Occlusal splints are usually made of hard resin and are, generally, carried on the mandibular jaw. Total occlusal splint are preferable to partial occlusal splint, except in some emergent cases. The smooth occlusal splints are needed for musculo-articular disorders when the indentated splints are reserved for mandibular repositioning in articular temporomandibular joint disorders.

A Michigan-type occlusal splint with spring-loaded mandibular protrusion functionality for treatment of anterior disk dislocation with reduction

For treatment of temporomandibular disorders Michigan-type splints are frequently used, as are mandibular advancement appliances for patients diagnosed with anterior disk dislocation. As both types show good results, the combination of these two mechanisms into one bimaxillary appliance was tested on eight patients where splint therapy had brought reduction but not complete elimination of the symptoms. An existing maxillary Michigan splint was modified so that advancement springs could be fitted and the generated forces were transmitted to a mandibular retainer, which did not interfere with the function of the splint. Treatment progress was monitored with computerized axiography and in all cases the axiographic tracings after the bimaxillary treatment showed no pattern indicative of disk dislocation under normal jaw movements. Myofascial pain symptoms, already improved by the pre-treatment with the Michigan splint, were found to be reduced further or eliminated completely. The approach of retrofitting a Michigan splint with the springs allowed for a versatile appliance, which required no occlusal alteration to the finely adapted splint but could as easily be brought back to the simple splint-functionality either for daytime use or for a period of stabilization of the result after successful treatment. Compliance was found to be very good and the short treatment period, together with the small force levels did not produce any detectable dental side effects.

Fitting acrylic occlusal splints and an experimental laminated appliance used in migraine prevention therapy

OBJECTIVE

To evaluate clinical procedures and chair time required to seat and adjust hard, heat-cured acrylic occlusal splints and an alternative laminated appliance developed to simplify construction of migraine prevention appliances.

DESIGN AND SETTING

Single-centre study in the Oral Medicine Clinic, The Royal Hospitals, Belfast, Northern Ireland.

METHOD

Questionnaires were distributed, January-May 2003, to operators fitting occlusal splints for 100 consecutive patients selected for migraine prevention therapy. Half the appliances were made in heat-polymerised acrylic with the remainder using a novel combination of ethylene vinyl acetate and light-curing urethane dimethacrylate. Information on operator experience, the nature of any fitting surface and occlusal adjustments together with an estimate of the time taken to make alterations was recorded.

KEY FINDINGS

The need for adjustment to seat appliances intraorally was significantly less for migraine prevention appliances made using an experimental laminating technique. Where modifications were necessary, there was no significant difference in the chair time required to fit either the heat-cured hard or experimental laminated migraine prevention appliance.

CONCLUSION

Provision of migraine prevention appliances may be more time efficient if the dental practitioner considers a laminated approach to construction.

Effects of Bartter's syndrome on dentition and dental treatment: A clinical report

Bartter's syndrome is an autosomal recessive form of severe volume depletion due to renal salt wasting. This clinical report describes the prosthodontic treatment for a 24-year-old man who suffers from Bartter's syndrome. The treatment plan included endodontic treatment of the maxillary anterior incisors and placement of cast dowel-and-core restorations because of reduced crown height. The patient's remaining teeth were restored with metal-ceramic crowns.

Occlusal device for diagnostic evaluation of maxillomandibular relationships in edentulous patients: A clinical technique

Identifying and recording appropriate occlusal vertical dimension (OVD) and centric relation positions during the treatment of edentulous patients is necessary for predictable and successful therapy. When alterations of existing conditions are indicated, it is beneficial for both the clinician and patient to evaluate the esthetics, phonetics, function, and comfort associated with planned changes in maxillomandibular relationships before fabricating new prostheses. A procedure used to modify existing unacceptable maxillomandibular relationships and clinically monitor the effects of these alterations prior to fabrication of definitive complete dentures is presented. Acceptance of the new OVD position by both the patient and dentist following an initial diagnostic phase is important to predictable and successful treatment.

Dental erosion in a group of British 14-year-old, school children. Part I: Prevalence and influence of differing socioeconomic backgrounds

OBJECTIVES

To establish the prevalence of erosion in a cluster random sample of 14- year-olds in Birmingham UK. To determine whether socioeconomic group influences the prevalence of erosion.

METHODS

The study group consisted of a cluster random sample of 14-year-old school children in Birmingham UK: 418 children were examined from 12 different schools; 209 were male and 209 female. The level of tooth wear was recorded using a modification of the (TWI) index of Smith and Knight (1984). The ACORN classification was used to assess the socioeconomic status of all children.

RESULTS

Results showed that 48% of the children had low erosion, 51% had moderate erosion and only 1% had severe erosion. There were statistically significant differences between males and females; more males had buccal/labial and lingual/palatal tooth surface erosion than females (Chi-square analysis P < 0.001). There was also significantly more erosion observed in teenagers in the lowest socioeconomic categories.

CONCLUSION

It was concluded that moderate levels of dental erosion are common in 14-year-old school children and this may lead to increasing clinical problems. There was significantly more erosion in children from low socioeconomic groups. Possible aetiological factors need to be investigated further.