Subluxation of the atlanto-axial joint

A case of post operative atlanto-axial dislocation is presented which was diagnosed on CT scan although the clinical signs and symptoms should have suggested the diagnosis. It is recommended that all patients who present with torticollis in the early post operative period should be considered to have C1-C2 dislocation and an orthopaedic opinion should be sought.     

The pathogenesis and microbiology of idiopathic cervicofacial abscesses

Sixty-three cases of idiopathic cervicofacial abscesses were surveyed. Several debilitating conditions, probably responsible for diminished resistance to infection, were found in association with the abscesses. The condition mainly affected children under two years of age, and the submandibular and submental regions were the most common sites of occurrence. The predominant infecting organism was Staphylococcus aureus. The abscess cavity was a statistically significant source of S. aureus, but the nose, ear, mouth, and skin did not appear to be significant sources of the pathogen. Antibiotics such as Dalacin C and gentamicin were found to be active against all the strains of S. aureus. Although incision and drainage was the most effective method of treatment for the abscesses, appropriate antibiotics may be prescribed for those cases where suppuration has not yet taken place.     

Effects of bone grafting on maxillary bone healing in the growing pig

The healing of defects of the lateral wall of the maxilla was studied in the growing pig. In Series I the effect on bone healing of AAA-bone and Kiel bone was compared with that of autografts, and in Series II a comparison was made between autografts and AAA-bone implants. It was found that both autografts and AAA-bone implants improved the rate of healing, but the Kiel bone had no effect. Comparison between autografts and AAA-bone implants in Series II did not show any significant differences. Therefore, it was concluded that AAA-bone can be a useful substitute for autografts in grafting procedures in the maxilla.     

Some properties of current composite materials.

This article reviews the physical and mechanical properties of fourteen currently available composite materials along with one silicate and one acrylic product for comparison.     

Tumors of the salivary glands: clinical analysis of 68 cases

Sixty-eight cases of tumors of the salivary glands treated at one institution over a six-year period were classified according to the World Health Organization criteria (Thackray AC, Sobin LH: Histological Typing of Salivary Gland Tumours. WHO, Geneva, 1972). Parotid, submandibular, and minor tumors were classified as epithelial, nonepithelial, or unclassified tumors or as allied conditions. Symptoms, demographic features, and management of the tumors are discussed.     

Evaluation of hydroxylapatite root implants in baboons

To determine if there is a need for close conformation of a hydroxylapatite implant to the root socket for successful prevention of alveolar ridge resorption after tooth extraction, second premolars and lateral incisors of six mature baboons were extracted bilaterally, and custom-fitted root replicas or half-length, plug-shaped forms of hydroxylapatite were implanted in the fresh sockets. Results showed that precise fit, as achieved by a custom-fitted implant, was not necessary for success. All implants were completely accepted, with evidence of new bone formation continuing for up to six months, the duration of the study. No resorption of the alveolar ridge was observed by gross or microscopic examination.     

Spontaneous regeneration of the condyle following hemimandibulectomy by disarticulation

A rare case of spontaneous regeneration of the mandibular condyle following hemimandibulectomy by disarticulation is described.     

Ankylosis of the mandible: analysis of 76 cases

A survey of 76 cases of ankylosis of the mandible in Nigerians is presented. Etiology, clinical features, radiographic findings, anesthetic techniques, surgical treatment, complications, and results are discussed. The operative technique used in each case depended on the site, extent, and type of ankylosis. Five-year follow-up data are reported. Of the 47 patients who were followed, the postoperative interincisal opening was retained in 25 (53.2%), varying degrees of reduction of mouth opening were observed in 17 (36.2%), and ankylosis recurred in five (10.6%). Lack of jaw opening exercise was believed to be responsible for relapse.     

Suspension and traction appliance for nasal,zygomatico-maxillary complex,and zygomatic arch fractures

The early reduction of fractures of the nasal bones, zygomatico-maxillary complex, and zygomatic arch is relatively simple in most cases. Frequently, however, patients suffer from concomitant head injuries that make immediate therapy inadvisable. Reduction after fibrosis has formed is not only difficult but often unsuccessful. Extraoral traction, suspension, supportive packing, or maxillomandibular fixation may be required in order to effect a good reduction.The traction or suspension appliances that have been used to date have been extraoral devices such as a plaster head cap, Kazanjian splint, and extraskeletal pin fixation with or without head frames.¹ The appliance to be discussed is different from those in that intraoral anchorage is used for extraoral suspension or traction.     

Proliferation of pulpal tissues following early transplantation of developing teeth

The responses of pulpal tissues were assessed histologically in teeth that had been transplanted as soon as crown formation was completed. The teeth were unerupted at the time of surgery and were transferred to other bony crypts, where attempts were made to reproduce their natural alignment. The pulpal tissues remained viable, although variations occurred in cellularity, vascularity and texture. There was widespread production of intrapulpal bone and osteodentine, and confluence of these tissues with proliferating apical and adjacent bone often resulted in ankylosis. The view was supported that transplanted dental tissues have a strong likelihood of surviving if the procedure is undertaken relatively early during tooth development; however, structural variations and ankylosis may compromise their subsequent value.     

Responses of periodontal tissues and cementum following transplantation of teeth

Responses of periodontal tissues, particularly cementum, were assessed histologically in teeth which had been transplanted after root formation was moderately well advanced. When the epithelial root sheath persisted, it was associated with continued root formation. In instances where the sheath disintegrated prematurely, either as a consequence of the surgery or of functional factors such as occlusal forces, normal root formation did not proceed, but there was rapid and extensive production of cellular cementum apically and along the root of the tooth. A zone of imperfect cementum formation was frequently seen between the preoperative cementum and that which developed postoperatively. Dilaceration of the tip of the root, with subsequent envelopment in a bulbous mass of cementum, commonly resulted.     

External fixation of the unstable zygomatic arch fracture

Fixation of unstable zygomatic arch fractures may be accomplished with a relatively noninvasive approach using 24-gauge wire and modification of a readily available material, the orthopedic finger splint.     

Blood pressure fluctuations in hypertensive patients during oral surgery

The lability of blood pressure during oral surgical procedures and the effects of antihypertensive drugs on this lability have not been investigated sufficiently to evaluate potential medical risks. The purpose of this study was to accurately evaluate blood pressure fluctuations during oral surgical procedures in three groups of patients: normotensive patients; stratum I hypertensive patients not taking medication; and stratum I hypertensive patients taking antihypertensive medication. Blood pressure measurements were recorded by an American Heart Association certified technician at baseline, immediately prior to surgery, during administration of the local anesthetic, during the surgical procedure, and 15 minutes after surgery. Analysis of variance indicated that the blood pressure fluctuations (systolic and diastolic) among these five intervals were not statistically significant for any of the groups. The clinical significance of the above findings is that stratum I hypertensive patients experience minimal fluctuations in blood pressure that are no greater than those in normotensive patients and, therefore, may present no greater clinical risk during the dental stress associated with certain oral surgical procedures.     

Acinic cell tumor of the minor salivary glands

The histologic characteristics and clinical features of six new cases of ACT of the minor salivary glands are reported. These neoplasms accounted for 3.8% of all the minor salivary gland tumors examined by our service.Three cell types were identified: acinar, vacuolated, and intercalated duct-cell. Those cell types were organized in three growth patterns: solid, papillary, and microcystic. Tumor cells were PAS positive both before and after treatment with diastase. Occasionally, they were slightly positive to mucicarmine staining.According to our study, ACT occurs in adult life, apparently without sex preference. Asymptomatic swelling was the most frequent presenting symptom; however, on occasion pain and ill-fitting dentures were reported. Most of the tumors in were described as fixed soft tissue masses, less than 1.5 cm in diameter. No recurrences or metastases were seen in any of the patients for a mean period of four years. Simple surgical removal was the therapeutic measure used in all cases.     

Bilateral pseudoankylosis of the temporomandibular joint due to synostoses between the mandible and maxilla

The occurrence of pseudoankylosis of the temporomandibular joints secondary to maxillary-mandibular synostoses is rare. These authors know of only two cases, previously reported and both were unilateral. A case is presented that is bilateral and symmetrical with a possible familial component.     

The biometry of mandibular osteotomy repair

The healing of experimental mandibular osteotomies in monkeys was monitored by biometric testing. Results indicate that full strength returns to the osteotomy site in 20 weeks. The implications for the treatment of osteotomies and fractures of the mandible in humans are discussed.