The prevalence of temporomandibular disorder signs in people with mental retardation.

The purpose of this study was to determine the prevalence of temporomandibular disorder (TMD) signs and tooth wear levels in a group of hospitalised patients with mental retardation (MR). A total of 118 patients with MR and 104 mentally healthy individuals (control) were included in this study. The groups consisted of equal numbers of male and female patients. TMD signs were evaluated according to the Research Diagnostic Criteria to assess the limitation in maximum mouth opening, the alterations in the mouth opening pathway and temporomandibular joint sounds. In addition, tooth wear was recorded. The frequency of at least one sign of TMD observed in patients with MR (79·7%) was significantly higher than in controls (69·2%) (P=0.03). In addition, 43.2% of the patients with MR had more than one sign of TMD compared with 28.8% of the control group (P = 0·02). Prevalence of each sign exhibited in the MR and control groups was as follows: limitation in mouth opening, 24·6% vs. 13·5% (P=0·02); deviation, 18·6% vs. 26·9% (P=0·001); deflection, 29·7% vs. 10·6% (P=0·001); TMJ sounds, 46·6% vs. 41·1% (P=0·43); bilateral joint sounds 28·8% vs. 16·3% (P=0·05) respectively. Prevalences of TMD signs were not different between genders in both groups (P>0·05). Severe tooth wear was evident in 43·2% of the patients with MR compared with 20·6% of the controls (P=0·001). In conclusion, patients with MR seem to be more prone to having TMD signs compared with the control population.

Evaluation of the slope of the articular eminence and the transverse angle of the glenoid fossa in an Anatolian population.

The purpose of this study was to compare a computer-aided method specially programmed for the measurement of the posterior angle of the articular eminence with formerly used methods, to investigate the angulation differences at different depths of slices, and to evaluate correlation with the transverse angulation. Three slices (central, medial, and lateral) at various depths of the glenoid fossa belonging to 64 dry skulls and two measurement methods were used in this study. The angulation of the articular eminence were measured and the transverse angle of each fossa calculated. No statistical difference was found between the articular eminence results of the two methods. According to the results, the one factor ANOVA central slice was found to be statistically steeper than the other two slices (p < 0.05) (central = 60.33 +/- 10.19, medial = 58.26 +/- 8.6, lateral 58.28 +/- 10.1). No correlation was found between the transverse angle of the inclination of the posterior slope angulation. It was concluded that the computer-aided method is more reliable and accurate and is much easier to use when compared to the manual method. An additional important finding of this study is that the inclination of the articular eminence should be evaluated at various depths of the temporomandibular joint.