Barry H. Hendler

The Use of Ultrasound to Determine the Position of the Mandibular Condyle

A randomized, single blind study of 20 patients examined the accuracy of ultrasound in establishing the position of the mandibular condyle in relation to the glenoid fossa. The sonographic technique is described. The temporomandibular joint was imaged sonographically with the patients in an open- and a closed-mouth position as a model for condylar sag and proper condylar seating, respectively, during mandibular ramus osteotomy procedures. One radiologist identified condylar position correctly in 38 of 40 still ultrasound images, with a sensitivity and a specificity of 95%. During real time ultrasound examination, it is possible to visualize varying degrees of condylar movement in relation to the glenoid fossa. The results of this study support the potential use of ultrasound as an adjunct to mandibular orthognathic surgery.

Holmium: YAG laser arthroscopy of the temporomandibular joint

A new pulsed midinfrared laser has become available for use in arthroscopic surgery of the temporomandibular joint (TMJ). This article reviews holmium:YAG (yttrium-aluminum-garnet) laser physics, its tissue effects, and reports initial experience with its use in TMJ arthroscopy. Because the Ho:YAG laser can precisely and rapidly resect cartilaginous tissues with only moderate necrosis, can function in a saline environment, and can be transmitted through conventional optical fibers, it has the potential of becoming a useful and adaptable system for TMJ arthroscopic surgery.

Odontogenic myxoma: Surgical management and an ultrastructural study

Odontogenic myxoma is a tumor of primitive mesenchyme, probably derived from the dental apparatus. Surgical management of this benign but locally aggressive tumor is either by curettage or en bloc resection. Two cases of odontogenic myxoma of the mandible are reported. In one case, en bloc resection. Two cases of odontogenic myxoma of the mandible are reported. In one case, en block resection with immediate reconstruction was undertaken. In the second case, the neoplasm was thoroughly curetted. The first case was studied by electron microscopy. Six ultrastructural studies of seven odontogenic myxomas have been previously reported. The ultrastructural features of odontogenic epithelium that may be present in myxomas of the jaws have been examined by electron microscopy once before. Our observations are in agreement with those of other workers who suggest that the connective tissue cell is the proliferating component of the tumor and is very similar to a fibroblast but has enough ultrastructural and functional features to deserve the term myxoblast. The majority of the tumor cells are metabolically active and secretory and there is adequate evidence that the tumor matrix consists of large amounts of mucopolysaccharides. It is reasonable, therefore, to conclude that myxoblasts secrete the mucoid matrix that is so characteristic of odontogenic myxomas. Unlike normal or neoplastic fibroblasts, the myxoblasts are not engaged in abundant synthesis of banded collagen throughout the entire lesion.

Mortised genioplasty in the treatment of obstructive sleep apnea: an historical perspective and modification of design.

We describe a modified technique for mortised genioglossus advancement for treating obstructive sleep apnea and review the history of osteotomies in this region. This new osteotomy technique allows for greater soft tissue advancement of the hypopharyngeal region. Anatomical data from a previous study were used to evaluate the dimensions of the anterior mandible and design an osteotomy that overcomes shortcomings of previous designs. These anatomic measurements enabled us to estimate the size and formulate a design utilized in the anterior mandible for the treatment of obstructive sleep apnea. We believe this design offers the greatest amount of muscular advancement by including genioglossus, geniohyoid, digastric, and mylohyoid. This advancement results in increasing the posterior airway space by volumetric expansion. Custom-designed fixation was utilized to increase stability laterally and decrease the risk of mandibular fracture. The design should be a significant aid in reconstruction of the hypopharyngeal airway in patients with obstructive sleep apnea.

Use of auricular cartilage in the repair of orbital floor defects

Various materials have been used to repair orbital defects. This article advocates the use of autogenous conchal cartilage, especially in the repair of large posttraumatic defects, where contour, biocompatibility, and strength are most important. The technique for harvesting the cartilage is reviewed, and a case demonstrating its successful use is reported.