Olof Eckerdal

Changes in the temporomandibular joint after oblique sliding osteotomy of the mandibular rami

Changes in the temporomandibular joint following oblique sliding osteotomy of the mandibular rami were studied using axial, frontal and lateral radiographs. The condyle/fossa relationship was also studied with regard to the effect of intraosseous wiring of the proximal fragment. Antero-inferior displacements of the condyles were regularly seen after the osteotomies. The use of intraosseous wiring had no adverse effects on the temporomandibular joint.

Skeletal remodelling in the temporomandibular joint after oblique sliding osteotomy of the mandibular rami.

Skeletal remodelling of the temporomandibular joints took place in 80% of cases after oblique sliding osteotomies of the rami. The new bone formation was found in both the condylar and temporal parts of the joint. It was mostly located on the posterior surface of the condyle and in the roof of the temporal part of the joint. No differences in skeletal remodelling were found between wiring and nonwiring cases.

A Method for Combined Microradiography and Histological Analysis of Non-Decalcified Hard Tissues

Sectioning of non-decalcified specimens of hard tissue from adult subjects is described. Frozen sectioning using the Jung K microtome was employed. Sections 10 to 50 μm, in special cases 5 μm in thickness were obtained. The entire specimen as well as sections of it could be roentgenographed by different methods including microradiography. The sections could then be histologically stained in the usual way. Thus the same section can be made to yield more than one type of information, and interesting correlation studies become feasible.

Intraosseous wiring in ramus osteotomy

The value of intraosseous wiring of the fragments after oblique osteotomy of the mandibular rami was studied. A wired group (14 patients) and a nonwired group (15 patients) were compared cephalometrically. There were only small differences between the groups but there was a tendency toward a smaller postoperative posterior rotation of the mandible in the wired group. It was concluded that in routine cases of mandibular prognathism wiring is not necessary.

Thin bony walls of the temporomandibular joint. Morphologic properties and tomographic reproduction.

The morphology of two thin bony walls in the medial third of the mandibular fossa is described on the basis of successive microtome sections of undecalcified temporomandibular joint specimens. The requirements for reproduction on thin bony walls at tomography with hypocycloidal movement are defined and discussed.

Thickness of the articular soft tissue of the temporal component in temporomandibular joints with and without disk displacement

OBJECTIVE The purpose of this investigation was to test the hypothesis that temporomandibular joint disk displacement is associated with significant functional adaptive changes of the articular soft tissue of the articular eminence. STUDY DESIGN Thirteen temporomandibular joint autopsy specimens with normal superior disk position and 12 with complete anterior disk displacement were cryosectioned, and sections were stained and photographed. At a magnification of x20 the soft tissue was measured (1) at the inflection point, (2) on the posterior slope, (3) at the apex, and (4) on the anterior slope of the articular eminence. RESULTS Displacement of a deformed or nondeformed temporomandibular joint disk without perforation of the posterior disk attachment was associated with significantly increased thickness of the articulating soft tissue at the apex and on the posterior and anterior slopes of the articulating eminence. When disk displacement was associated with a perforation of the posterior disk attachment, the soft tissue was not significantly thicker than in joints with normal superior disk position. CONCLUSIONS Increase in articulating soft tissue thickness is interpreted as an adaptive mechanism to maintain the condyle path and withstand excessive loading at interposition of the temporomandibular joint components. When the plasticity of the tissues is surpassed, the adaptation will be thwarted and replaced by tissue breakdown.

External bony auditory canal and the tympanic bone. Morphologic properties and influences on the tomographic reproduction.

The external bony auditory canal is morphologically defined as concerns the shape and calibre in successive plane parallel histologic sections of the petrous bone. The sagittal dimensions and structural appearances of the tympanic bone are demonstrated. The morphologic properties defined constitute a basis for the evaluation of the tomographic image formation in this region.