line in patients with a history of MMR. In addition, perioperative CPK values of more than 20,000 IU are highly suggestive of MH susceptibility. Patients exhibiting MMR should be evaluated for MH susceptibility and myopathies-S. J. MCKENNA Reprint requests to Dr. Rosenberg: Professor and Chairman, Department of Anesthesiology, Hahnemann University Hospital. Broad and Vine Streets, Philadelphia. PA 19102-I 192.
Dacron Mesh Tray and Cancellous Bone in Reconstruction of Mandibular Defects. Albert TW, Smith JD. Everts EC, et al. Arch Otolaryngol 112:January 1986 The treatment of 17 mandibular continuity defects with a Dacron-urethane mesh tray filled with cancellous bone for mandibular reconstruction is presented. The tray is malleable but stiff, can easily be cut with scissors, and may be used to replace any missing portion of the mandible. The technique for placing the tray is discussed in detail. The authors state that the Dacron mesh tray overcomes several of the disadvantages of the metal trays used previously for reconstruction. There is little concern about galvanic effect from contact of dissimilar metals if stainless steel wires are utilized. The edges are not sharp, and the tray is enmeshed with the graft. The patient may be irradiated after surgery without upsetting symmetry calculations or scattering radiation. The Dacron-urethane tray has more elasticity than bone and thus allows the transmission of normal stress and strain to the graft, which is important in healing and remodeling. The authors state that their success or lack thereof with immediate reconstruction is similar to that of others. The major factor in failure seems to be the intraoral contamination resulting from breakdown of the overlying muCOW-DONALDM.PRIMLEY Reprint requests to Dr. Smith: 3181 S.W. Sam Jackson Road, Portland, OR 97201. Parasagittal
of the Head and Neck. Cahill DR.
Mayo Clin Proc 61:127-139,
Although almost every anatomic atlas or textbook contains drawings of midsagittal plane dissections, only a few contain anatomic information about the parasagittal planes. In this article the author presents a series of illustrations depicting the anatomic features of the head and neck in four parasagittal sections to the left of the midline, which were drawn from photographs of carefully dissected sections from a frozen, embalmed cadaver. Because of the profusion of anatomic structures in these
sections, two to four drawings of each section are presented, labeled according to system, such as nervous, muscular. skeletal, visceral, and vascular. This series of anatomic illustrations is an excellent review of sectional anatomy and demonstrates complex anatomic relationships that are often directly applicable to the diagnosis of clinical problems or to the planning of surgical procedures. With new magnetic resonance imaging techniques, the sagittal plane is one of the most frequently selected planes for the imaging of head and neck anatomy. Since considerable attention has been given to the details of each of the major systems, the illustrations should be particularly useful for clinicians and surgeons alike.Donald M. Primley Reprint requests to Dr. Cahill: Department of Anatomy. Mayo Clinic, Rochester,
Mandibular Augmentation with Hydroxyapatite. Beirne 0, Curtis T, Greenspan J. J Prosthet Dent 55:3 1986 Two separate studies were reported in this article. The clinical study involved nine female patients with severe mandibular alveolar atrophy. The authors investigated the success of hydroxyapatite augmentation in improving denture stability. Also, in five patients in whom secondary vestibuloplasty was necessary, biopsy specimens were obtained to study the histologic response around the hydroxyapatite implants. Five patients experienced paresthesia or anesthesia of the lip that had resolved in only one of the patients at 13 months. The interval between augmentation and biopsy in the five patients requiring secondary vestibuloplasty procedures was 3 months for two patients. and 5, 6, and 13 months for the remaining three. Direct bone-hydroxyapatite interface was not found in any of the specimens. Instead, the implanted material was found to be surrounded by a fibrous scar and a few inflammatory cells. It did bear the stress of the mandibular denture and improve stability, however. The animal study consisted of the placement of a mixture of hydroxyapatite and collagen in mandibular defects in ten Charles River rats to determine whether the collagen would act as a binder and improve the bone-implant interface to prevent migration of the material. The results suggested that the collagen neither interfered with the healing of the bone around the hydroxyapatite nor stimulated bone formation at the implant-bone interface.JAMESB.MURPHY Reprint requests to Dr. Beirne: University of Washington, School of Dentistry SB-24. Seattle. WA 98195.