A 15-year follow-up of temporomandibular joint symptoms and magnetic resonance imaging findings in whiplash patients: a prospective, controlled study.

OBJECTIVE: This study aimed to determine the incidence, prevalence, and progression of temporomandibular joint (TMJ) magnetic resonance (MR) imaging findings and symptoms in patients over a 15-year period after whiplash trauma, compared with control participants. STUDY DESIGN: Sixty consecutive patients were enrolled directly after whiplash trauma. The study protocol included TMJ MR imaging at inception and 15 years later, as well as a questionnaire and interview at inception, at 1-year follow-up, and at 15-year follow-up. Fifty-seven patients (95%) participated in all three examinations (85% for MR imaging). Fifty matched control participants were examined. RESULTS: The prevalence of TMJ symptoms was significantly higher in patients compared with control participants at inception (44% vs 20%, P = .0055) and remained significantly higher throughout the study period. The prevalence of disk displacement did not differ significantly between groups either at inception (63% vs 53%) or at 15-year follow-up (63% vs 55%). CONCLUSIONS: This prospective 15-year follow-up suggests that the development of TMJ symptoms, both immediate and delayed, is common in whiplash patients.

Temporomandibular joints in asymptomatic and symptomatic nonpatient volunteers: a prospective 15-year follow-up clinical and MR imaging study.

PURPOSE: To determine the incidence, prevalence, and progression of temporomandibular joint (TMJ) magnetic resonance (MR) imaging findings and symptoms during 15 years in adult asymptomatic and symptomatic volunteers (nonpatients). MATERIALS AND METHODS: A regional committee for medical research ethics approved the study, and informed volunteer consent was obtained. Fifty-three volunteers were examined at study inception. For clinical assessment, a self-administered questionnaire was given, followed by an interview with each volunteer at study inception, at 1 year later, and at 15 years later. Bilateral TMJ MR imaging and clinical examination were performed at inception and at 15-year follow-up. The MR images were assessed for disk position, bone status, and joint fluid. All 53 volunteers participated at 1-year follow-up, and 50 of 53 volunteers participated at 15-year follow-up; of these 50 volunteers, 47 underwent MR imaging. The Fisher exact test was used to determine differences between groups, and the Wilcoxon signed-rank test was used to determine differences in prevalence of TMJ symptoms among the three examination times. RESULTS: At study inception, TMJ disk displacement was observed in 31% of asymptomatic volunteers (nine of 29) compared with 89% of symptomatic volunteers (16 of 18, P < .001). Inceptive TMJ status was maintained after 15 years in 91% (43 of 47). Unilateral progression was observed in four volunteers (9%); one was symptomatic and three were asymptomatic. Progression involved development of new disk displacement (n = 1), development of new bone changes (n = 2), and aggravation from reducing to nonreducing disk displacement (n = 1). Prevalence of TMJ symptoms did not change significantly between examination times (P = .77). TMJ clicking was the most common clinical symptom. CONCLUSION: Volunteers with mild symptoms had a prevalence of disk displacement of the same magnitude as that reported in patients, although most volunteers, symptomatic as well as asymptomatic, maintained their TMJ status during 15 years.

Titanium screw implants in optimization of radiographic evaluation of facial growth in longitudinal animal studies.

The aim of this study was to develop a method that optimizes the reliability of longitudinal radiographic evaluation of small and fast-growing animals, such as the rabbit. Because the use of conventional cephalometric methods, including superimposition of serial radiographs, is more problematic in small animals than in humans, two titanium-alloy screws were placed 10 mm apart in the sagittal crest of the parietal bone in 10 growing New Zealand white rabbits. The anterior screw served as holder for a steel pin that, in turn, secured the fixation of the rabbit's head to a specially designed cephalostat. A lateral cephalogram of each animal was exposed on four occasions at one-month intervals. Computer-aided superimpositions were made of all four cephalograms from each animal using the screws in the calvarium as reference structures. To evaluate the method, the superimpositions were repeated after three to eight weeks, and the superimposition reproducibility was calculated. From the results, it can be concluded that the method allows congruent positioning of the animal skull relative to the film-focus assembly at repeated radiographic examinations. Furthermore, it introduces readily identified reference structures in the animal skull that can be used at high-precision superimposition of serial radiographs.