Cross-Cultural Validation of the Thai Oral Health Impact Profile for Temporomandibular Disorders

OBJECTIVES

The Oral Health Impact Profile for Temporomandibular Disorders (OHIP-TMDs) is a validated condition-specific outcome measure to help guide decision-making in the management of the condition. There is no Thai version of OHIP-TMDs, and therefore the original English version needs cross-cultural adaptation translation, and validation with a Thai population to reduce the anomalies due to language and cultural differences. This study aimed to develop the Thai-language version of OHIP-TMDs, perform a cross-cultural adaptation to Thailand, and assess its content validity, internal consistency, reliability, and construct validity.

METHODS

The original English version of OHIP-TMDs was forward and backward translated into Thai language using the International Network for Orofacial Pain and Related Disorders methodology (INfORM) protocol for cross-cultural adaptation. The Content Validity Index (CVI) was performed by 5 orofacial pain (OFP) specialists to establish content validity. The OHIP-TMDs-T was then tested in 2 groups of Thai dental patients including 110 TMD patients and 110 control participants. The internal reliability and test-retest reliability (n = 30) were investigated in the TMD group using Cronbach alpha coefficient and intraclass correlation coefficient (2-way mixed effect model), respectively. The difference in OHIP-TMDs-T score between the TMD group and control group was investigated for known group validity.

RESULTS

Cronbach alpha and intraclass correlation coefficients were 0.942 and 0.797, respectively. The CVI collected from the OFP specialists was 0.92. There was a statistical difference in the OHIP-TMDs-T overall score between the TMD group (95% CI, 40-46) and control group (95% CI, 2.0-3.4) (Z = 9.060, r = 1, P < .001).

CONCLUSIONS

The OHIP-TMDs-T is a valid and reliable tool for evaluating the quality of life and the impact on oral health in Thai patients with TMD.

Occlusal splint and combined multiwave locked system laser therapy demonstrated differential patient-reported outcomes and clinical parameters: A randomized controlled trial in patients with temporomandibular disorder

PURPOSE

To evaluate the impact of occlusal splint plus laser therapy (OS + LT) compared with OS alone on the patient-reported outcomes and clinical parameters of patients with temporomandibular disorders (TMDs).

METHODS

Twenty-three patients with TMDs were randomly assigned to two treatment approaches: OS and OS + LT (multiwave locked system). The two outcomes were clinical parameters (mouth-opening distances, number of muscles and TMJs with pain) and patient-reported outcomes (pain score and oral health-related quality of life [OHRQoL] determined using the 14-item oral health impact profile [OHIP-14]). The outcomes were measured at four time points: baseline, 2 weeks, 1 and 3 months after treatment. According to DC/TMD Axis I classification, the participants were diagnosed as having pain only and pain with intraarticular joint disorder. Adjusting for age and sex, the outcome changes were analysed using generalized estimating models at a 5% significance level.

RESULTS

The pain-free mouth-opening distance of the patients who received OS + LT continuously increased from 2 weeks to 3 months. However, the value was significantly increased at 3 months in patients who received OS alone. The unassisted mouth-opening distance significantly increased after 3 months in both groups. In both treatment approaches, the number of muscles and TMJs with pain, as well as the pain and OHIP-14 scores gradually decreased from baseline to 3 months.

CONCLUSIONS

The patients who received OS and OS + LT demonstrated better OHRQoL and clinical parameters during 3 months after treatment. An improvement in the pain-free mouth-opening distance at 2 weeks was found only in OS plus LT group; however, this difference may not be clinically significant.

Wear effects between polymethyl methacrylate occlusal splints and opposing dentin surfaces during bruxism mimicking events

OBJECTIVES

To compare the surface wear rate between polymethyl methacrylate (PMMA)-based occlusal splints and opposing dentin-exposed teeth in bruxism simulating models.

MATERIALS AND METHODS

PMMA-based occlusal splints and extracted premolars were tested on a chewing stimulator at 30,000 or 60,000 cycles. Dentin wear was measured under a stereomicroscope and PMMA wear was determined with an optical profilometer. In addition, wear surface topography was assessed and quantified by scanning electron microscopy (SEM).

RESULTS

Wear rate of PMMA was significantly greater (11 times) than that of dentin specimens at 60,000 cycles, though these findings were not observed at 30,000 cycles. When comparing wear rates within each group at different duration cycles, PMMA surfaces exhibited an average wear rate 1.4 times higher with high duration cycles, while dentin surfaces displayed a marginal decrease in wear. In SEM micrographs, PMMA surfaces displayed more wear abrasion lines with higher duration cycles. However, dentin surfaces did not exhibit major differences between low and high duration cycles.

CONCLUSION

Wear rate on PMMA-based occlusal splints remarkably increases upon high chewing cycles mimicking bruxism comparing with the rate on dentin. Hence, it is reasonable for bruxing patients to wear single-arch PMMA-based occlusal splints to protect opposing dentin-exposed teeth.

Factors associated with the oral health-related quality of life of patients with temporomandibular disorder at the final follow-up visit: a cross-sectional study

OBJECTIVES

To determine the oral health-related quality of life (OHRQoL) of temporomandibular disorder (TMD) patients at the final follow-up visit, and to investigate the associated factors.

MATERIALS AND METHODS

This cross-sectional study comprised 227 TMD patients. Dependent variable was OHRQoL determined by telephone interview using the 14-item Oral Health Impact Profile (OHIP-14) questionnaire after the final follow-up visit. Independent variables were collected from dental records, comprising age, sex, treatment duration, diagnosis, clinical parameters (mouth-opening distances), and pain perception. TMD patients were diagnosed as having masticatory muscle disorders (TMDM), temporomandibular joint (TMJ) disorders (TMDJ), or combined muscle and TMJ disorders (TMDC). Bivariate analyses and multivariable linear regression were used to analyze the factors associated with OHIP-14 scores.

RESULTS

Bivariate analyses demonstrated higher OHIP-14 scores in younger patients, females, having TMDC, and lower mouth-opening distance. Multivariable analysis demonstrated the association of higher OHIP-14 scores with being younger and having TMDC. Participants with TMDC demonstrated greater improvement in unassisted mouth-opening distance, compared with the other clinical diagnosis groups.

CONCLUSIONS

At the final follow-up visit, oral health impact problems were reported mainly in physical pain and psychological discomfort domains. Better OHRQoL was found in older, and TMDM or TMDJ patients.

Altered activity in the nucleus raphe magnus underlies cortical hyperexcitability and facilitates trigeminal nociception in a rat model of medication overuse headache

BACKGROUND

The pathogenesis of medication overuse headache (MOH) involves hyperexcitability of cortical and trigeminal neurons. Derangement of the brainstem modulating system, especially raphe nuclei may contribute to this hyperexcitability. The present study aimed to investigate the involvement of the nucleus raphe magnus (NRM) in the development of cortical and trigeminal hyperexcitability in a rat model of MOH.

RESULTS

Chronic treatment with acetaminophen increased the frequency of cortical spreading depression (CSD) and the number of c-Fos-immunoreactive (Fos-IR) neurons in the trigeminal nucleus caudalis (TNC). In the control group, muscimol microinjected into the NRM increased significantly the frequency of CSD-evoked direct current shift and Fos-IR neurons in the TNC. This facilitating effect was not found in rats with chronic acetaminophen exposure. In a model of migraine induced by intravenous systemic infusion of nitroglycerin (NTG), rats with chronic exposure to acetaminophen exhibited significantly more frequent neuronal firing in the TNC and greater Fos-IR than those without the acetaminophen treatment. Muscimol microinjection increased neuronal firing in the TNC in control rats, but not in acetaminophen-treated rats. The number of Fos-IR cells in TNC was not changed significantly.

CONCLUSION

Chronic exposure to acetaminophen alters the function of the NRM contributing to cortical hyperexcitability and facilitating trigeminal nociception.