A Longitudinal and Comparative Computed-tomographic Study on Osteoarthritic Change of the Temporomandibular Joint between Treatment and Non-treatment Groups in Young Age

Abstract

The aim of this study is to assess the longitudinal change of the temporomandibular joint (TMJ) with osteoarthritis (OA) on computed tomography (CT) comparing treatment group with non-treatment group of Korean temporomandibular disorder (TMD) patients in young age. CT and clinical records of 44 patients diagnosed as TMJ OA based on the evident destructive condylar bone change of the TMJ on CT were reviewed. Treatment group was consisted of 29 patients taken conservative treatments including instruction of behavioral control, physical therapy and occlusal stabilization splint therapy with periodic follow-up. Non-treatment group was consisted of 15 patients taken neither treatment nor additional follow-up but for explanation on diagnosis. OA change of the TMJ was evaluated on two sets of CT images taken with 1.5±0.5 years interval. Clinical information at the time of CT examination including prevalence of self-reported pain, range of maximum and comfortable (painless) mouth opening was also investigated and analyzed. Total 70 joints (47 joints of treatment group and 23 joints of non-treatment group) were divided into 3 categories of improved, no change and worsened CT groups according to the longitudinal OA change on CT images. Joints of improved CT group were more than a half in both treatment (55.3%) and non-treatment groups (60.9%). The overall extent of OA change (destructive change index, DSTI) showed no significant differences by both treatment and time. However, general aspects of DSTI value change were more favorable in treatment group. In treatment group, the initial DSTI of improved OA was higher (3.32, =more destructive) and that of worsened OA was lower (1.86, =less destructive) significantly. And also range of maximum and comfortable mouth opening of treatment group increased significantly (p=0.02 and 0.003) compared to non-treatment group. Prevalence of self-reported pain decreased more in treatment group, not statistically significant, though.

The obtained results are as follows: 1. Improved OA joints were the most in numbers in both treatment and non-treatment groups. 2. The extent of destructive change of TMJ OA was not significantly different by time and treatment. 3. In treatment group, although not statistically significant, general aspects of destructive bone change was more favorable compared to non-treatment group. 4. Analyzed clinical information, the range of mouth opening was significantly increased in treatment group. Prevalence of self-reported pain was also decreased more in treatment group, not statistically significant.

Although the results of this study may imply that the destruction of hard tissue of TMJ OA has its own disease course and less affected by conventional treatment protocols including occlusal stabilization splint therapy than it is expected, to improve not only destructive osseous change of TMJ OA but also clinical symptoms and jaw functioning, conservative treatments including instruction of behavioral control, physical therapy and occlusal stabilization splint therapy with periodic follow-up should be considered.