engleski

Disk position of the temporomandibular joint in asymptomatic subject

Disc displacement (DD) is the most frequent form of temporomandibular disorders (TMD). The purpose of this study was to determine the disk position of the temporomandibular joint (TMJ) in young asymptomatic individulas. A magnetic resonance imaging (MRI) examinations was carried out in 50 TMJs of 25 dental school students (7 male and 18 female) with a mean age of 23, 4 years. Students were clinically examined by means of manual functional analysis and any clinical signs or history of DD or degenerative joint disease were excluded. The quantitative analysis of the position and the relationship between the disk and the condyles was described using Kurita et all&#8217; s method of measuring the relative and absolute distances of reference points (Fig 1). The TP tangent is defined by the intersections of points on the lowest part of the articular eminence (T) and the highest part of the external auditory canal (P). The intersections of the TP tangent and the perpendiculars drawn from the back edge of the disk and the condyles make out the C and D points. The TP, TC and TD distances are measured in milimeters. MR images revealed anterior disk position in 5 (20%) individuals, or 6 (12%) examined joints (Fig. 2). DD with reduction was revealed in three joints (Fig. 3) and in three TMJ DD without reduction (Fig. 4). There was statistically significant difference to the relative disk position (Kruskal-Wallis test KW(1, 50)=15, 297, p<0, 001), but there was no statistically significant difference to the relative condyle position (Kruskal-Wallis test KW(1, 50)=1, 092, p=1, 092) between joints with the physiological disk position and joints with DD. MRI of the TMJ can provide essential information about the position of the disc in groups of well-selected asymptomatic subjects. A considerably high prevalence of different DD types has been observed in subjects without either ID medical history or clinical findings of the DD. The prevalence rate has amounted to as much as 12-33% of the examined population, that is, 8-45% of the individually examined TMJs. Asymptomatic DD may signify a potential risk factor for later occurrence of symptoms and signs of TMD. Since the ethiopathogenesis of TMD has not been explained as well as that of artrogenic form of TMD &#8211; internal derangements, a possible cause of temporomandibular pain at TMD patients is also the anterior displacement of articular disk.

temporomandibular joint; disk displacement; asymptomatic subject; magnetic resonance imaging

nije evidentirano