Stabilization Splint Treatment of TMD (TMD)

Efficacy of Stabilization Splint Treatment on Facial Pain - One-year Follow-up

The aim of this randomized controlled trial was to assess the efficacy of stabilization splint treatment on TMD-related facial pain and oral health-related quality of life during a one-year follow-up. Eighty TMD patients were randomly assigned to two groups: splint group (n=39) and control group (n=41). The patients in the splint group were treated with a stabilization splint and received counseling and instructions for masticatory muscle exercises. The controls received only counseling and instructions for masticatory muscles exercises.

The outcome variables were the intensity of facial pain (as measured with visual analogue scale, VAS), patients' subjective estimate of symptoms and treatment outcome, as well as Oral Heath Impact Profile (OHIP)-14. The differences in variables between the groups at each follow-up points (1 month, 3 months, 6 months and 1 year after baseline) were analyzed using regression models. Group status and presence of psychosocial symptoms were included as the explanatory factor and baseline VAS, gender, age, length of treatment and general health status as confounders.

Study Overview

• Status: Completed
• Conditions: Facial Pain; Temporomandibular Disorder
• Intervention / Treatment: Device: Stabilization splint treatment

Detailed Description

DESIGN OF THE STUDY The study sample consisted originally of 80 patients (18 men, 62 women) who were referred to the Oral and Maxillofacial Department in Oulu University Hospital, Oulu, Finland, for treatment of TMD-related facial pain. The patients were examined between March 2008 and August 2010. The inclusion criteria were the following: 1. clinically diagnosed TMD as defined by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) (1), 2. minimum of 20 years of age and 3. lack of long-term illnesses (i.e. rheumatoid arthritis) that may affect TMJs or the masticatory muscles.

Using computer generated random numbers, the patients were randomly assigned to two groups: splint group and control group. Patients in the control group (n=41) were given counseling and guidance for masticatory muscle exercises. In addition to these, the patients in the splint group (n=39) were also treated with a stabilization splint.

DATA COLLECTION The patients had four follow-ups: at about 1 month, 3 months, 6 months and one year after the baseline evaluation. The same dentist specialized in stomatognathic physiology (KS) conducted all of the follow-up examinations, being unaware of the group status of the patients. At baseline the psychosocial screening (depression symptoms, non-specific physical symptoms, pain-related disability) was performed using RDC/TMD Axis II instruments. At baseline and at all the follow-ups the intensity of the facial pain was assessed using Visual Analogue Scale (VAS). The patients' subjective estimates of the effects of the treatment were evaluated with a questionnaire, using a scale from 1 to 4 (1= Very good effect, 2= Treatment has helped to some extent, 3= No difference / Cannot tell and 4= Symptoms worsened). The patients' general health status was also inquired by a questionnaire (on a scale of 1-5, 1=excellent, 2=very good, 3=good, 4=moderate, 5=poor). The patients filled in the Oral Health Impact Profile-14 (OHIP-14) questionnaire before treatment and at 3 months, 6 months and 1 year.

TREATMENT PROCEDURES The stabilization splints were made of heat-cured acrylic by the same dental technician. The occlusion of the splint was defined in the centric relation occlusion using wax (Astynax, Associated Dental Products Ltd, UK). The patients were instructed to use the splint every night during the course of the study.

All the patients in both groups were instructed to perform a standardized program for masticatory muscle exercises as described by Carlsson and Magnusson (1992). At the beginning of the training program, active mouth openings, laterotrusion and protrusion movements were performed. The mandible was held in the maximal positions for a few seconds on each movement. Thereafter, these movements were made towards resistance (using the patient's own fingers). After jaw exercises, the patients were suggested to open the jaw wide, stretching it with fingers a few times for 10 to 20 seconds. These movements were repeated 7 to 10 times per training session, and the sessions were performed 2-3 times per day. The patients received written instructions, and the movements were also demonstrated by the dentist before the treatment, and reprised if necessary. The instructions for masticatory muscle exercises were given by the same dentist (KS) at the first visit. At every examination the patients were reminded to use the splint and/or to perform the exercises at a regular basis.

The stabilization splint treatments were performed by two other dentists who were instructed in the treatment method.

ATTRITION All of the patients in the total sample were defined as belonging to the "intention-to-treat" (ITT) population. Thus, the ITT also included those who switched groups or those who in whichever group received other treatment than initially planned based on the group criteria. In the analysis, the number of days each patient had stayed in the assigned groups was taken into account. The patients who had stayed in their assigned groups for the whole follow-up period were defined as forming the "per-protocol" (PP) population.

STATISTICAL ANALYSIS Statistical significances of the differences in patients' estimate of the effects of the treatment between the groups were analyzed using chi-square test. Differences in means of the change in VAS between the groups were tested using ANOVA. VAS change was calculated by subtracting VAS at one-year follow-up from baseline VAS. The fluctuation of facial pain during the study (VAS) was demonstrated with a box-plot diagram. At first, linear regression analysis was used to analyze factors associated with change in VAS after one-year follow-up in both the ITT and PP populations. Group status was included as the explanatory factor and baseline VAS, gender, age, length of treatment and general health status were included as confounders. Linear mixed-effect regression model was used to analyse factors associated with change in OHIP severity during the 1-year follow-up, taking into account treatment time, age, gender and group status. The effect of depression and non-specific physical symptoms on the intensity of facial pain, as measured with visual analogue scale (VAS) was estimated with linear mixed models.

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria

• clinically diagnosed TMD according to the RDC/TMD
• age > 20 years

Exclusion Criteria:

• Presence of any chronic diseases, such as rheumatoid arthritis, that may affect the TMJ or the masticatory muscles

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Stabilization splint group; The patients in the splint group were treated with a stabilization splint and received counseling and instructions for masticatory muscle exercises	Device: Stabilization splint treatment; The stabilization splints were made of heat-cured acrylic by the same dental technician. The occlusion of the splint was defined in the centric relation occlusion using wax (Astynax, Associated Dental Products Ltd, UK). The patients were instructed to use the splint every night during the course of the study. The patients were instructed to perform a standardized program for masticatory muscle exercises. At the beginning of the training program, active mouth openings, laterotrusive movements and protrusive movements were performed. The mandible was held in the maximal positions for a few seconds on each movement. Thereafter, these movements were made towards resistance (using the patient's own fingers). After jaw exercises, the patients were suggested to open the jaw wide, stretching it with fingers a few times for 10 to 20 seconds. These movements were repeated 7 to 10 times per training session, and the sessions were performed 2-3 times per day.
NO_INTERVENTION: Control group; The controls received only counseling and instructions for masticatory muscles exercises.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in facial pain intensity	The change of the intensity of the facial pain, assessed using Visual Analogue Scale (VAS) on a 0 (no pain) to 10 (pain as bad as could be) rating	from baseline to 1-year follow-up
Subjective estimate on treatment outcome	The patients' subjective estimates of the effects of the treatment were evaluated with a questionnaire, using a scale from 1 to 4 (1= Very good effect, 2= Treatment has helped to some extent, 3= No difference / Cannot tell and 4= Symptoms worsened).	1 month follow-up
Subjective estimate on treatment outcome	The patients' subjective estimates of the effects of the treatment were evaluated with a questionnaire, using a scale from 1 to 4 (1= Very good effect, 2= Treatment has helped to some extent, 3= No difference / Cannot tell and 4= Symptoms worsened).	3 month follow-up
Subjective estimate on treatment outcome	The patients' subjective estimates of the effects of the treatment were evaluated with a questionnaire, using a scale from 1 to 4 (1= Very good effect, 2= Treatment has helped to some extent, 3= No difference / Cannot tell and 4= Symptoms worsened).	6 month follow-up
Subjective estimate on treatment outcome	The patients' subjective estimates of the effects of the treatment were evaluated with a questionnaire, using a scale from 1 to 4 (1= Very good effect, 2= Treatment has helped to some extent, 3= No difference / Cannot tell and 4= Symptoms worsened).	1 year follow-up
Subjective estimate on symptom severity	The subjective assessment of the severity of TMD symptoms after treatment was assessed by means of a scale on 1 to 5 (1= 'no symptoms'/ 'symptoms not significant', 2 = 'mild symptoms', 3 = 'moderate symptoms', 4 = 'severe symptoms', 5 = 'intolerable symptoms')	1 month follow-up
Subjective estimate on symptom severity	The subjective assessment of the severity of TMD symptoms after treatment was assessed by means of a scale on 1 to 5 (1= 'no symptoms'/ 'symptoms not significant', 2 = 'mild symptoms', 3 = 'moderate symptoms', 4 = 'severe symptoms', 5 = 'intolerable symptoms')	3 month follow-up
Subjective estimate on symptom severity	The subjective assessment of the severity of TMD symptoms after treatment was assessed by means of a scale on 1 to 5 (1= 'no symptoms'/ 'symptoms not significant', 2 = 'mild symptoms', 3 = 'moderate symptoms', 4 = 'severe symptoms', 5 = 'intolerable symptoms')	6 month follow-up
Subjective estimate on symptom severity	The subjective assessment of the severity of TMD symptoms after treatment was assessed by means of a scale on 1 to 5 (1= 'no symptoms'/ 'symptoms not significant', 2 = 'mild symptoms', 3 = 'moderate symptoms', 4 = 'severe symptoms', 5 = 'intolerable symptoms')	1 year follow-up
Change of Oral health related quality of life (OHRQoL)	Change of Oral health related quality of life was assessed using Oral Health Impact Profile (OHIP-14, sum score from 0 to 56, the higher value indicating poorer OHRQoL)	from baseline to 1-year follow-up

Collaborators and Investigators

• Sponsor: University of Oulu
• Investigators: Principal Investigator: Kirsi Sipilä, Professor, Research Unit of Oral Health Sciences, University of Oulu, Finland

Publications and helpful links

General Publications

• Dworkin SF, LeResche L. Research diagnostic criteria for temporomandibular disorders: review, criteria, examinations and specifications, critique. J Craniomandib Disord. 1992 Fall;6(4):301-55. No abstract available.
• Huttunen J, Qvintus V, Suominen AL, Sipila K. Role of psychosocial factors on treatment outcome of temporomandibular disorders. Acta Odontol Scand. 2019 Mar;77(2):119-125. doi: 10.1080/00016357.2018.1511057. Epub 2018 Sep 28.
• Kokkola O, Suominen AL, Qvintus V, Myllykangas R, Lahti S, Tolvanen M, Sipila K. Efficacy of stabilisation splint treatment on the oral health-related quality of life-A randomised controlled one-year follow-up trial. J Oral Rehabil. 2018 May;45(5):355-362. doi: 10.1111/joor.12622.
• Qvintus V, Suominen AL, Huttunen J, Raustia A, Ylostalo P, Sipila K. Efficacy of stabilisation splint treatment on facial pain - 1-year follow-up. J Oral Rehabil. 2015 Jun;42(6):439-46. doi: 10.1111/joor.12275. Epub 2015 Jan 17.

Study record dates

Study Major Dates

• Study Start (ACTUAL): March 1, 2008
• Primary Completion (ACTUAL): August 31, 2010
• Study Completion (ACTUAL): August 31, 2010

Study Registration Dates

• First Submitted: January 20, 2022
• First Submitted That Met QC Criteria: February 3, 2022
• First Posted (ACTUAL): February 15, 2022

Study Record Updates

• Last Update Posted (ACTUAL): February 15, 2022
• Last Update Submitted That Met QC Criteria: February 3, 2022
• Last Verified: February 1, 2022

More Information

Terms related to this study

• Keywords: treatment; clinical trial; TMD; facial pain; temporomandibular disorders; stabilization splint
• Additional Relevant MeSH Terms: Pathologic Processes; Pain; Neurologic Manifestations; Disease Attributes; Joint Diseases; Musculoskeletal Diseases; Muscular Diseases; Stomatognathic Diseases; Jaw Diseases; Craniomandibular Disorders; Mandibular Diseases; Myofascial Pain Syndromes; Temporomandibular Joint Disorders; Temporomandibular Joint Dysfunction Syndrome; Facial Pain; Facies
• Other Study ID Numbers: 29/2007

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No