Management of painful temporomandibular disorders: Methods and overview of The National Dental Practice-Based Research Network prospective cohort study

BACKGROUND

Patients often seek consultation with dentists for temporomandibular disorders (TMDs). The objectives of this article were to describe the methods of a large prospective cohort study of painful TMD management, practitioners' and patients' characteristics, and practitioners' initial treatment recommendations conducted by The National Dental Practice-Based Research Network (the "network").

METHODS

Participating dentists recruited into this study treated patients seeking treatment for painful TMDs. The authors developed self-report instruments based on well-accepted instruments. The authors collected demographics, biopsychosocial characteristics, TMD symptoms, diagnoses, treatments, treatment adherence, and painful TMDs and jaw function outcomes through 6 months.

RESULTS

Participating dentists were predominately White (76.8%) and male (62.2%), had a mean age of 52 years, and were general practitioners (73.5%) with 23.8% having completed an orofacial pain residency. Of the 1,901 patients with painful TMDs recruited, the predominant demographics were White (84.3%) and female (83.3%). Patients' mean age was 44 years, 88.8% self-reported good to excellent health, and 85.9% had education beyond high school. Eighty-two percent had pain or stiffness of the jaw on awakening, and 40.3% had low-intensity pain. The most frequent diagnoses were myalgia (72.4%) and headache attributed to TMDs (51.0%). Self-care instruction (89.4%), intraoral appliances (75.4%), and medications (57.6%) were recommended frequently.

CONCLUSIONS

The characteristics of this TMD cohort include those typical of US patients with painful TMDs. Network practitioners typically managed TMDs using conservative treatments.

PRACTICAL IMPLICATIONS

This study provides credible data regarding painful TMDs and TMD management provided by network practitioners across the United States. Knowledge acquired of treatment recommendations and patient reports may support future research and improve dental school curricula.

Predictors of Long-Term Temporomandibular Disorder Pain Intensity: An 8-Year Cohort Study

AIMS

To investigate, in individuals with pain-related temporomandibular disorder (TMD), the association of long-term pain intensity with baseline health-related quality of life (HRQoL) and jaw functional limitation.

METHODS

Of 513 cases with baseline pain-related TMD (masticatory muscle and/or temporomandibular joint [TMJ] pain), 273 were reevaluated after 8 years, and 258 of them had complete baseline data for Jaw Functional Limitation Scale (JFLS) scores and HRQoL measured by the Physical Component Summary (PCS) and Mental Component Summary (MCS) scores of the 12-item Short Form Health Survey and follow-up data for Characteristic Pain Intensity (CPI) from the Graded Chronic Pain Scale. Secondary analyses of existing data quantified the effects of primary (PCS, MCS) and secondary (JFLS) predictors on follow-up CPI by using multivariable linear regression. Sensitivity analyses considered differences between the included participants (n = 258) and those who were not included (n = 255) by using inverse probability weighting. Interactions of baseline predictors with age, sex, and baseline CPI were evaluated using multivariable linear regression.

RESULTS

The score for baseline PCS, but not MCS or JFLS, was associated with follow-up CPI (P = .012). One standard deviation (SD = 9.0)-higher baseline PCS score predicted an overall 3.2-point-lower follow-up CPI (95% confidence interval -5.8 to -0.7) after adjusting for age, sex, MCS, JFLS, and baseline CPI scores. However, the effect of PCS score was not uniform: the association between PCS and follow-up CPI scores was statistically significant for participants with baseline CPI ≥ 51.3/100 and clinically significant for participants with baseline CPI ≥ 68.7/100. Adjustment for TMD treatments and sensitivity analyses had negligible effect.

CONCLUSION

In participants with moderate to severe baseline TMD pain intensity, higher baseline physical HRQoL predicted lower TMD pain intensity at 8 years follow-up. PCS score could contribute to a multifactorial long-term TMD pain prediction model.

Large-scale clinical endodontic research in the National Dental Practice-Based Research Network: study overview and methods

INTRODUCTION

This article reports on the feasibility of conducting a large-scale endodontic prospective cohort study in The National Dental Practice-Based Research Network. This study was designed to measure pain and burden associated with initial orthograde root canal therapy (RCT) and to explore potential prognostic factors for pain outcomes. The main objectives of this first report in a series are to describe the project's feasibility and methods and the demographics of the sample obtained.

METHODS

Sixty-two dentist practitioner-investigators (ie, 46 generalists and 16 endodontists) in 5 geographic areas were certified within the network and trained regarding the standardized study protocol. Enrollment and baseline data collection occurred over 6 months with postobturation follow-up for another 6 months. Patients and dentists completed questionnaires before and immediately after treatment visits. Patients also completed questionnaires at 1 week, 3 months, and 6 months after obturation.

RESULTS

Enrollment exceeded target expectations, with 708 eligible patient-participants. Questionnaire return rates were good, ranging between 90% and 100%. Patient demographics were typical of persons who receive RCT in the United States (ie, mean age = 48 years [standard deviation = 13 years], with most being female [59%], college educated [81%], white non-Hispanic [86%], and having dental insurance [81%]). The tooth types being treated were also typical (ie, 61% molars, 28% premolars, and 11% anteriors, with maxillary teeth being predominant [59%]).

CONCLUSIONS

This study shows the feasibility of conducting large-scale endodontic prospective cohort studies in the network. Patients were rapidly recruited with high levels of compliance in data collection.

Reliability and validity of Axis I of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) with proposed revisions

  The research diagnostic criteria for temporomandibular disorders (RDC/TMD) have been employed internationally since 1992 for the study of temporomandibular muscle and joint disorders (TMD). This diagnostic protocol incorporates a dual system for assessment of TMD for Axis I physical diagnoses as well as Axis II psychological status and pain-related disability. Because the reliability and criterion validity of RDC/TMD had not yet been comprehensively characterised, the National Institute of Dental and Craniofacial Research funded in 2001 the most definitive research to date on the RDC/TMD as a U01 project entitled, 'Research Diagnostic Criteria: Reliability and Validity'. The results of this multi-site collaboration involving the University of Minnesota, the University of Washington, and the University at Buffalo were first reported at a pre-session workshop of the Toronto general session of the International Association of Dental Research on 2 July 2008. Summaries of five reports from this meeting are presented in this paper including: (i) reliability of RDC/TMD Axis I diagnoses based on clinical signs and symptoms; (ii) reliability of radiographic interpretations used for RDC/TMD Axis I diagnoses; (iii) reliability of self-report data used for RDC/TMD Axis I diagnoses; (iv) validity of RDC/TMD Axis I diagnoses based on clinical signs and symptoms; and (v) proposed revisions of the RDC/TMD Axis I diagnostic algorithms.

The Research Diagnostic Criteria for Temporomandibular Disorders. VI: future directions

The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Validation Project has provided the first comprehensive assessment of reliability and validity of the original Axis I and II. In addition, Axis I of the RDC/TMD was revised with estimates of reliability and validity. These findings are reported in the five preceding articles in this series. The aim of this article is to present further revisions of Axis I and II for consideration by the TMD research and clinical communities. Potential Axis I revisions include addressing concerns with orofacial pain differential diagnosis and changes in nomenclature in an attempt to provide improved consistency with other musculoskeletal diagnostic systems. In addition, expansion of the RDC/TMD to include the less common TMD conditions and disorders would make it more comprehensive and clinically useful. The original standards for diagnostic sensitivity ( < or = 0.70) and specificity (< or = 0.95) should be reconsidered to reflect changes in the field since the RDC/TMD was published in 1992. Pertaining to Axis II, current recommendations for all chronic pain conditions include standardized instruments and expansion of the domains assessed. In addition, there is need for improved clinical efficiency of Axis II instruments and for exploring methods to better integrate Axis I and II in clinical settings.

The Research Diagnostic Criteria for Temporomandibular Disorders. V: methods used to establish and validate revised Axis I diagnostic algorithms

AIMS

To derive reliable and valid revised Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms for clinical TMD diagnoses.

METHODS

The multisite RDC/TMD Validation Project's dataset (614 TMD community and clinic cases, and 91 controls) was used to derive revised algorithms for Axis I TMD diagnoses. Validity of diagnostic algorithms was assessed relative to reference standards, the latter based on consensus diagnoses rendered by two TMD experts using criterion examination data, including temporomandibular joint imaging. Cutoff points for target validity were sensitivity > or = 0.70 and specificity > or = 0.95. Reliability of revised algorithms was assessed in 27 study participants.

RESULTS

Revised algorithm sensitivity and specificity exceeded the target levels for myofascial pain (0.82, 0.99, respectively) and myofascial pain with limited opening (0.93, 0.97). Combining diagnoses for any myofascial pain showed sensitivity of 0.91 and specificity of 1.00. For joint pain, target sensitivity and specificity were observed (0.92, 0.96) when arthralgia and osteoarthritis were combined as "any joint pain." Disc displacement without reduction with limited opening demonstrated target sensitivity and specificity (0.80, 0.97). For the other disc displacement diagnoses, osteoarthritis and osteoarthrosis, sensitivity was below target (0.35 to 0.53), and specificity ranged from 0.80 to meeting target. Kappa for revised algorithm diagnostic reliability was > or =0.63.

CONCLUSION

Revised RDC/TMD Axis I TMD diagnostic algorithms are recommended for myofascial pain and joint pain as reliable and valid. However, revised clinical criteria alone, without recourse to imaging, are inadequate for valid diagnosis of two of the three disc displacements as well as osteoarthritis and osteoarthrosis.

The Research Diagnostic Criteria For Temporomandibular Disorders. II: reliability of Axis I diagnoses and selected clinical measures

AIMS

The primary aim was to determine new estimates for the measurement reliability of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms. A second aim was to present data on the reliability of key clinical measures of the diagnostic algorithms.

METHODS

Kappa (k), computed by generalized estimate equation procedures, was selected as the primary estimate of interexaminer reliability. Intersite reliability of six examiners from three study sites was assessed annually over the 5-year period of the RDC/TMD Validation Project. Intrasite reliability was monitored throughout the validation study by comparing RDC/TMD data collections performed on the same day by the test examiner and a criterion examiner.

RESULTS

Intersite calibrations included a total of 180 subjects. Intersite reliability of RDC/TMD diagnoses was excellent (k > 0.75) when myofascial pain diagnoses (Ia or Ib) were grouped. Good reliability was observed for discrete myofascial pain diagnoses Ia (k = 0.62) and Ib (k = 0.58), for disc displacement with reduction (k = 0.63), disc displacement without reduction with limited opening (k = 0.62), arthralgia (k = 0.55), and when joint pain (IIIa or IIIb) was grouped (k = 0.59). Reliability of less frequently observed diagnoses such as disc displacements without reduction without limited opening, and osteoarthrosis (IIIb, IIIc), was poor to marginally fair (k = 0.31-0.43). Intrasite monitoring results (n = 705) approximated intersite reliability estimates. The greatest difference in paired estimates was 0.18 (IIc).

CONCLUSION

Reliability of the RDC/TMD protocol was good to excellent for myofascial pain, arthralgia, disc displacement with reduction, and disc displacement without reduction with limited opening. Reliability was poor to marginally fair for disc displacement without reduction without limited opening and osteoarthrosis.

The Research Diagnostic Criteria for Temporomandibular Disorders. I: overview and methodology for assessment of validity

AIMS

The purpose of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Validation Project was to assess the diagnostic validity of this examination protocol. The aim of this article is to provide an overview of the project's methodology, descriptive statistics, and data for the study participant sample. This article also details the development of reliable methods to establish the reference standards for assessing criterion validity of the Axis I RDC/TMD diagnoses.

METHODS

The Axis I reference standards were based on the consensus of two criterion examiners independently performing a comprehensive history, clinical examination, and evaluation of imaging. Intersite reliability was assessed annually for criterion examiners and radiologists. Criterion examination reliability was also assessed within study sites.

RESULTS

Study participant demographics were comparable to those of participants in previous studies using the RDC/TMD. Diagnostic agreement of the criterion examiners with each other and with the consensus-based reference standards was excellent with all kappas > or = 0.81, except for osteoarthrosis (moderate agreement, k = 0.53). Intrasite criterion examiner agreement with reference standards was excellent (k > or = 0.95). Intersite reliability of the radiologists for detecting computed tomography-disclosed osteoarthrosis and magnetic resonance imaging-disclosed disc displacement was good to excellent (k = 0.71 and 0.84, respectively).

CONCLUSION

The Validation Project study population was appropriate for assessing the reliability and validity of the RDC/TMD Axis I and II. The reference standards used to assess the validity of Axis I TMD were based on reliable and clinically credible methods.

Systematic review and meta-analysis of randomized controlled trials evaluating intraoral orthopedic appliances for temporomandibular disorders

AIMS

To conduct a systematic review with meta-analysis of randomized controlled trials (RCTs) that have assessed the efficacy of intraoral orthopedic appliances to reduce pain in patients with temporomandibular disorders affecting muscle and joint (TMJD) compared to subjects receiving placebo control, no treatment, or other treatments.

METHODS

A search strategy of MEDLINE, the Cochrane Library, the Cochrane CENTRAL Register, and manual search identified all English language publications of RCTs for intraoral appliance treatment of TMJD pain during the years of January 1966 to March 2006. Two additional studies from 2006 were added during the review process. Selection criteria included RCTs assessing the efficacy of hard and soft stabilization appliances, anterior positioning appliances, anterior bite appliances, and other appliance types for TMJD pain. Pain relief outcome measures were used in the meta-analyses, and the QUORUM criteria for data abstraction were used. A quality analysis of the methods of each RCT was conducted using the CONSORT criteria. The review findings were expressed both as a qualitative review and, where possible, as a mathematical synthesis using meta-analysis of results.

RESULTS

A total of 47 publications citing 44 RCTs with 2,218 subjects were included. Ten RCTs were included in two meta-analyses. In the first meta-analysis of seven studies with 385 patients, a hard stabilization appliance was found to improve TMJD pain compared to non-occluding appliance. The overall odds ratio (OR) of 2.46 was statistically significant (P = .001), with a 95% confidence interval of 1.56 to 3.67. In the second meta-analysis of three studies including 216 patients, a hard stabilization appliance was found to improve TMJD pain compared to no-treatment controls. The overall OR of 2.15 was positive but not statistically significant, with a 95% confidence interval of 0.80 to 5.75. The quality (0 to 1) of the studies was moderate, with a mean of 55% of quality criteria being met, suggesting some susceptibility to systematic bias may have existed.

CONCLUSION

Hard stabilization appliances, when adjusted properly, have good evidence of modest efficacy in the treatment of TMJD pain compared to non-occluding appliances and no treatment. Other types of appliances, including soft stabilization appliances, anterior positioning appliances, and anterior bite appliances, have some RCT evidence of efficacy in reducing TMJD pain. However, the potential for adverse events with these appliances is higher and suggests the need for close monitoring in their use.

The Research Diagnostic Criteria for Temporomandibular Disorders. III: validity of Axis I diagnoses

AIMS

To estimate the criterion validity of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I TMD diagnoses.

METHODS

A combined total of 614 TMD community and clinic cases and 91 controls were examined at three study sites. RDC/TMD Axis I diagnoses were algorithmically derived from an examination performed by calibrated dental hygienists. Reference standards ("gold standards") were established by means of consensus diagnoses rendered by two TMD experts using all available clinical data, including imaging findings. Validity of the RDC/TMD Axis I TMD diagnoses was estimated relative to the reference-standard diagnoses (gold standard diagnoses). Target sensitivity and specificity were set a priori at greater than or equal to 0.70 and greater than or equal to 0.95, respectively.

RESULTS

Target sensitivity and specificity were not observed for any of the eight RDC/TMD diagnoses. The highest validity was achieved for Group Ia myofascial pain (sensitivity 0.65, specificity 0.92) and Group Ib myofascial pain with limited opening (sensitivity 0.79, specificity 0.92). Target sensitivity and specificity were observed only when both Group I diagnoses were combined (0.87 and 0.98, respectively). For Group II (disc displacements) and Group III (arthralgia, arthritis, arthrosis) diagnoses, all estimates for sensitivity were below target (0.03 to 0.53), and specificity ranged from below to on target (0.86 to 0.99).

CONCLUSION

The RDC/TMD Axis I TMD diagnoses did not reach the targets set at sensitivity of > or = 0.70 and specificity of > or = 0.95. Target validity was obtained only for myofascial pain without differentiation between normal and limited opening. Revision of the current Axis I TMD diagnostic algorithms is warranted to improve their validity.

Critical appraisal of methods used in randomized controlled trials of treatments for temporomandibular disorders

AIMS

To evaluate the quality of methods used in randomized controlled trials (RCTs) of treatments for management of pain and dysfunction associated with temporomandibular muscle and joint disorders (TMJD) and to discuss the implications for future RCTs.

METHODS

A systematic review was made of RCTs that were implemented from 1966 through March 2006, to evaluate six types of treatments for TMJD: orthopedic appliances, occlusal therapy, physical medicine modalities, pharmacologic therapy, cognitive-behavioral and psychological therapy, and temporomandibular joint surgery. A quality assessment of 210 published RCTs assessing the internal and external validity of these RCTs was conducted using the Consolidated Standards of Reporting Trials (CONSORT) criteria adapted to the methods of the studies.

RESULTS

Independent assessments by raters demonstrated consistency with a mean intraclass correlation coefficient of 0.63 (95% confidence interval). The mean percent of criteria met was 58%, with only 10% of the RCTs meeting the four most important criteria.

CONCLUSIONS

Much of the evidence base for TMJD treatments may be susceptible to systematic bias and most past studies should be interpreted with caution. However, a scatter plot of RCT quality versus year of publication shows improvement in RCT quality over time, suggesting that future studies may continue to improve methods that minimize bias.

Electric toothbrush application is a reliable and valid test for differentiating temporomandibular disorders pain patients from controls

Background

Current methods for identifying patients with pain hypersensitivity are sufficiently complex to limit their widespread application in clinical settings. We assessed the reliability and validity of a simple multi-modal vibrotactile stimulus, applied using an electric toothbrush, to evaluate its potential as a screening tool for central sensitization.

Methods

Fourteen female temporomandibular disorders (TMD) subjects with myofascial pain (RDC/TMD Ia or Ib) and arthralgia (RDC/TMD IIIa) were compared to 13 pain-free controls of matched age and gender. Vibrotactile stimulus was performed with an electric toothbrush, applied with 1 pound pressure for 30 seconds in four locations: over the lateral pole of the temporomandibular joint, masseter, temporalis, and mid-ventral surface of forearm. Pain intensity (0–10) was recorded following the stimulus at 0, 15, 30, and 60 seconds. Test-retest reliability was assessed with measurements from 8 participants, taken 2–12 hours apart. Case versus control differentiation involved comparison of area under the curve (AUC). A receiver operating characteristic (ROC) curve was used to determine cutoff AUC scores for maximum sensitivity and specificity for this multi-modal vibrotactile stimulus.

Results

Test-retest reliability resulted in an ICC of 0.87 for all 4 pooled sites. ROC-determined AUC cutoff scores resulted in a sensitivity of 57% and specificity of 92% for all 4 pooled sites.

Conclusion

The electric toothbrush stimulus had excellent test-retest reliability. Validity of the scores was demonstrated with modest sensitivity and good specificity for differentiating TMD pain patients from controls, which are acceptable properties for a screening test.

Randomized effectiveness study of four therapeutic strategies for TMJ closed lock

For individuals with temporomandibular joint (TMJ) disc displacement without reduction with limited mouth opening (closed lock), interventions vary from minimal treatment to surgery. In a single-blind trial, 106 individuals with TMJ closed lock were randomized among medical management, rehabilitation, arthroscopic surgery with post-operative rehabilitation, or arthroplasty with post-operative rehabilitation. Evaluations at baseline, 3, 6, 12, 18, 24, and 60 months used the Craniomandibular Index (CMI) and Symptom Severity Index (SSI) for jaw function and TMJ pain respectively. Using an intention-to-treat analysis, we observed no between-group difference at any follow-up for CMI (p > or = 0.33) or SSI (p > or = 0.08). Both outcomes showed within-group improvement (p < 0.0001) for all groups. The findings of this study suggest that primary treatment for individuals with TMJ closed lock should consist of medical management or rehabilitation. The use of this approach will avoid unnecessary surgical procedures.

A randomized clinical trial assessing the efficacy of adding 6 x 6 exercises to self-care for the treatment of masticatory myofascial pain

AIMS

To determine whether Rocabado's 6 x 6 exercise program has an added benefit to self-care alone in reducing myofascial jaw pain and improving forward head posture (FHP) in subjects with myofascial pain and FHP at the end of 4 weeks.

METHODS

In this double-blinded trial, 45 subjects (43 female and 2 male, mean age 24 years) were randomly assigned to self-care or self-care + 6 X 6 exercises. The primary outcome measure was intensity of jaw pain on a numerical graphic rating scale (NGRS). Secondary outcome measures were jaw pain on a verbal rating scale (VRS), neck pain (NGRS and VRS), and change in head posture. Twenty-one subjects per group resulted in 80% power to detect a difference of 2 in the NGRS for intensity of jaw pain. Alpha was set at .05 for statistical significance.

RESULTS

Both groups showed significant statistical (P = .001) and clinical (> 2 on NGRS) improvement in jaw pain intensity. Jaw pain and neck pain improved significantly (P < .01) in both groups. There were no differences between groups for any of the measures. A significant change in head posture was not detected in either group.

CONCLUSION

The 6 x 6 exercises were not significantly more beneficial in reducing the intensity of jaw and neck pain than self-care alone. Furthermore, they were not beneficial in improving head posture within the 4-week duration of this study.

Reliability and validity of a new fingertip-shaped pressure algometer for assessing pressure pain thresholds in the temporomandibular joint and masticatory muscles

AIMS

To test in vitro and in vivo the reliability and accuracy of a new algometer, the pressure algometer for palpation (PAP), for measuring pressure pain thresholds (PPTs) and to compare its features with those of a commercially available pressure algometer.

METHODS

For in vitro accuracy testing, 6 repeated measurements were made at 8 defined test weights from 0.5 to 5 lb. In vivo validity testing compared the PAP to a standard instrument, the hand-held Somedic algometer, at 16 sites including the masticatory muscles, the temporomandibular joints, and the frontalis (as the control site) in 15 temporomandibular disorder (TMD) cases and 15 controls. Intraexaminer reliability was also assessed for both algometers.

RESULTS

In vitro reliability was high, with coefficients of variation of < 5% and a single-measurement standard deviation of 2.1 kPa. Accuracy was also high, with PAP measurements correlating with test weights at r = .99 (P < .001). Repeated measures reliability in vivo was high, with intraclass correlation estimates of 0.73 to 0.96 for the PAP and 0.78 to 0.99 for the Somedic algometer. PPT values correlated moderately between the 2 devices (r ranged from 0.38 to 0.66; P < or = .05) and were consistently higher for the PAP at all sites (P < .001). Differences between controls and TMD cases were also significant for both algometers (P < .006).

CONCLUSION

Both the PAP and the Somedic algometer showed high reliability. Concurrent validity was demonstrated by statistically significant correlations between the devices. Both showed equally high capacity for differentiating TMD cases from controls. The PAP yielded significantly higher PPTs than the Somedic algometer.

The Influence of Dynamic Occlusal Interferences on Probing Depth and Attachment Level: Results of the Study of Health in Pomerania (SHIP)

BACKGROUND

The purpose of this study was to investigate potential associations between dynamic occlusal interferences and signs of periodontal disease in posterior teeth based on dental and medical measurements obtained from a population-based sample in the cross-sectional epidemiological study entitled, "Study of Health in Pomerania" (SHIP).

METHODS

Medical history and dental and sociodemographic parameters of 2,980 representatively selected dentate subjects, 20 to 79 years of age, were collected. The analysis was performed on posterior teeth only using a mixed linear model that considers the clustered structure of the data. The model also was adjusted with respect to known risk factors for periodontal disease.

RESULTS

The presence of non-working side contacts only was significantly related to probing depth (P<0.0001) and attachment loss (P=0.001). The presence of non-working side contacts and working side contacts on the same tooth was significantly related to increased probing depth (P=0.004) but not attachment level. The effect magnitude was a mean increase of 0.13 mm for probing depth and 0.14 mm in attachment loss. Known risk factors for periodontal disease that also showed significant associations with probing depth and attachment loss included male gender, age, smoking, education, and plaque score. Other factors significantly related to probing depth and/or attachment loss were tilted teeth, restored occlusal surfaces versus sound surfaces, elongated teeth, and tooth type (molar versus premolar).

CONCLUSION

The effect of non-working contacts on periodontal disease status was discernible, but weak in terms of magnitude and specificity.

The effect of exogenous glucosamine hydrochloride on the proteoglycan concentration of the articular disc of the rabbit temporomandibular joint

AIMS

To test the effect of glucosamine hydrochloride (glucosamine-HCl) on the proteoglycan (PG) concentration of the articular disc of non-arthritic temporomandibular joints (TMJs) in rabbits.

METHODS

Twenty-four of 48 New Zealand white 10- to 12-week-old male rabbits (2.2 kg average) were injected with the irritant chymopapain in the knee joint. Both groups of 24 rabbits were divided into 3 groups of 8 animals. The rabbits were fed a control diet or a diet supplemented with glucosamine-HCl incorporated at a level to provide 20 mg/kg (approximating the recommended dose 500 mg/tid/70 kg man) or 100 mg/kg, for 8 weeks. Sulfated glycosaminoglycans (GAGs) were assayed in protease K digests of the TMJ articular disc by dimethylmethylene blue method to quantify PG concentration. The groups were compared with 2-way analysis of variance.

RESULTS

Glucosamine-HCl did not cause a significant change in the PG concentration of the TMJ articular disc (P > .8). There was also no detectable effect of chymopapain injection to the knee joint on the TMJ (P > .07) and no interaction between glucosamine-HCl treatment and chymopapain injection (P > .3).

CONCLUSION

Glucosamine-HCl has no effect on PG concentration of the articular disc of non-arthritic TMJ in rabbits.

Long-term study of temporomandibular joint surgery with alloplastic implants compared with nonimplant surgery and nonsurgical rehabilitation for painful temporomandibular joint disc displacement

PURPOSE

The purpose of this study was to determine the long-term objective and subjective outcomes of temporomandibular joint (TMJ) implant surgery for the treatment of painful TMJ disc displacement using temporary Silastic (Dow Corning Corporation, Midland, MI), permanent Silastic, or Proplast (Vitek, Houston, TX) implants to replace the disc. These cases were compared with other cases of the same diagnosis treated with either nonsurgical rehabilitation or nonimplant surgery involving discectomy or disc repair procedures.

MATERIALS AND METHODS

A cross-sectional study was conducted among 466 patients who received treatment for unilateral or bilateral TMJ disc displacement before January 1, 1990. The 5 treatment groups noted above were compared for long-term outcomes. Objective outcome measurements for jaw function were performed using a calibrated examiner and the Craniomandibular Index (CMI). Subjective (self-reported) outcomes were obtained relative to jaw function (Mandibular Function Impairment Questionnaire [MFIQ]), symptom severity (Symptom Severity Index [SSI]), and the impact of pain (Global Pain Impact [GPI] scale).

RESULTS

The results, adjusted for gender, baseline tomogram score, and baseline symptom scores, showed that the nonsurgical rehabilitation group (n = 159) and the group having TMJ surgery without implants (n = 149) had statistically better results than the group who underwent surgery with a Proplast implant (n = 94). These between-group differences included both objective signs (CMI), and subjective reports of jaw function (MFIQ), symptom severity (SSI), and global pain impact (GPI). The MFIQ score associated with the nonsurgical rehabilitation group was also statistically better than for the Silastic implant groups, including both the temporary (n = 31) and permanent (n = 33) implants. Clinical differences between groups were slight.

CONCLUSION

This study suggests that the use of interpositional disc implants in TMJ surgery is not associated with improved outcomes when compared with nonimplant surgery or nonsurgical rehabilitation.

The effectiveness of adding pharmacologic treatment with clonazepam or cyclobenzaprine to patient education and self-care for the treatment of jaw pain upon awakening: a randomized clinical trial

AIMS

To compare the relative effectiveness of a benzodiazepine (clonazepam), a muscle relaxant (cyclobenzaprine), and a placebo for the treatment of jaw pain upon awakening, when each is combined with the recommended nonpharmacological components of initial medical management.

METHODS

Forty-one subjects were recruited with a diagnosis of myofascial pain based on the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). All subjects were given education about TMD and a self-care program. Subjects were randomized into 1 of 3 groups: clonazepam (0.5 mg/night), cyclobenzaprine (10 mg/night), or placebo. The primary outcome measure was the subjects' average intensity of jaw pain upon awakening over the prior week. This was recorded with a visual analog scale at pretreatment and at the completion of the 3-week trial. A secondary outcome measure was sleep quality based on the Pittsburg Sleep Quality Index.

RESULTS

Within-group changes showed a statistically significant (P < .001) decrease in jaw pain upon awakening for all 3 groups. Between-group differences demonstrated a statistically significant difference (P < .016) between cyclobenzaprine and placebo, and between cyclobenzaprine and clonazepam. There was no significant effect on sleep quality in any group.

CONCLUSION

This study suggests that cyclobenzaprine is statistically superior to either placebo or clonazepam when added to self-care and education for the management of jaw pain upon awakening. Based on the subjects' report of sleep quality, these medications failed to significantly improve sleep in the short term.

Preliminary results from disinfection of irreversible hydrocolloid impressions

The virucidal efficacy of germicides acting on an irreversible hydrocolloid surface is not known. Tests that are currently performed on germicides do not simulate the conditions under which the germicides are often used. One major concern for the dental profession is the disinfection of dental impressions, particularly irreversible hydrocolloid impressions. This study was designed to test the biocidal action of germicides against an enveloped virus on an irreversible hydrocolloid surface. The disinfection model, which was developed to simulate clinical conditions, specified the use of vesicular stomatitus virus, an animal virus amenable to safe handling. A 0.5% sodium hypochlorite spray inactivated the virus when the spray was allowed to remain on the impression 3 to 10 minutes. The iodophor disinfectant required a 3- to 10-minute immersion for total inactivation. Although 2% glutaraldehyde achieved total viral inactivation in less than 1 minute, the authors conclude that short disinfectant sprays, in general, are not an appropriate disinfection method.

Current prosthodontic practice: a dental laboratory survey

A survey was distributed to dental laboratory owners at the 1988 annual meeting of the Minnesota Dental Laboratory Association. Current laboratory practice in infection control, the use of nonprecious alloys, the amount of time devoted to complete removable prosthodontics, and complete denture laboratory techniques were surveyed. Responses indicate a moderate level of awareness and compliance with infection control techniques recommended by the American Dental Association, a declining demand for removable prosthodontic services, a high percentage of use of nonprecious alloys, and a very high rate of porcelain occlusion requested by dental practitioners. Comparisons with other laboratory surveys and the implications of these results for undergraduate education in prosthodontics are discussed.