The trans-nasal Kirschner wire as a method of fixation of the unstable fracture of the zygomatic complex

A technique for the fixation of the unstable zygomatic complex is described and compared with other methods currently available.     

In-vitro cultural parameters and protein and prostaglandin secretion of epithelial cells derived from porcine rests of Malassez.

Cultured epithelial cells (E-cells) derived from the rests of Malassez exhibited a diploid karyotype with a modal number of 38 chromosomes, which is the number reported for the pig. Unlike the cell rests in vivo, which appear to be quiescent, E-cells in culture secreted several proteins. The doubling time of E-cells was 36 h. 80 per cent remained sufficiently viable to attach to the culture dish after extensive trypsinization. Their size distribution was unchanged over 9 subcultures. The E-cells secreted prostaglandins of the E and F series into the culture medium. As prostaglandins have been implicated in bone resorption associated with dental cysts, prostaglandin production by epithelial cells derived from the rests of Malassez may contribute to the mechanism of cyst growth.     

Effects of 3 months frequent consumption of hydrogenated starch hydrolysate (Lycasin), maltitol, sorbitol and xylitol on human dental plaque.

Lozenges containing hydrogenated starch hydrolysate (Lycasin), maltitol, sorbitol or xylitol were consumed 4 times daily during 3 months by 4 groups of persons (in all 85 subjects). In the maltitol-, sorbitol- and xylitol-group the plque wet weights were of the same magnitude before and after the test period. In the Lycasin-group, a higher value was found after than before the 3-month period (p less than 0.01). The acid production in suspensions of dental plaque material from Lycasin, maltitol and sorbitol expressed as per cent of that from glucose was approximately the same before and after the test period. From xylitol no acid production could be demonstrated either before or after the 3-month period. There were no statistically significant differences between the plaque pH-changes induced by rinsing with 50% solutions of Lycasin, maltitol, sorbitol or xylitol before and after the test period. However, there was a tendency (p less than 0.05) towards lower pH-values induced by the maltitrol and sorbitol rinse after the 3-month period compared with before. No difference in the relative numbers of facultative anaerobic streptococci. Streptococcus mutans or facultative anaerobic lactobacilli before and after the test period was found.     

Systemic tuberculosis initially seen as an oral ulceration: report of case.

A 67-year-old white man was seen for the treatment of a painful oral ulceration. His medical history was highly suggestive of systemic disease. Radiographs of the chest and cultures of sputum were positive for tuberculosis. The incidence, appearance, and characteristics of oral tubercular lesions have been presented. The diagnosis of tuberculosis should be considered along with carcinoma, syphilis, fungal disease, and trauma whenever granulomatous ulcerations appear in the oral cavity.     

The effects of diphenylhydantoin and vitamin D deficiency on developing teeth in the rat.

The effects of short-term (21 days) and long-term (116 days) treatment with oral diphenylhydantoin (DPH, 6 g/kg diet) on the development of rat teeth was investigated. Long-term DPH reduced the size of the incisors and of all the molars except the upper first. There was also a reduction in tooth weight and both changes were shown to be independent of body weight. Short-term DPH reduced the size of the incisors and upper third and second molars only.The relationship of these lesions to the shortened tooth roots found in epileptics on chronic anticonvulsant therapy and the stunted root development seen in hypoparathyroidism is discussed. It is suggested that DPH may induce a state of “pseudohypoparathyroidism” by inhibiting the action of parathyroid hormone on bone and tooth. This complication would appear to be additional to the so-called “anticonvulsant-induced osteomalacia”.     

Comparative study of healing and remodeling in various bones.

The effects of normal physiologic stimuli on healing and remodeling in various bones of different embryogenic origin in the rabbit and dog were compared. The findings disclosed that the healing and remodeling of the tibia and mandible were consistent with the magnitude of the forces that act on these bones; namely, the tension created by muscle contraction and the compression exerted by body weight in the tibia, and masticatory compression in the mandible. The slower healing and remodeling in the maxilla was attributed to the selection of the excision of bone in the edentulous site with minimal masticatory compression and muscle-pull tension. The excision of the bone in the skull appeared to heal by fibrous tissue with no evidence of remodeling, which is consistent with the minimal external forces that act on this bone.     

Dental informatics for Australia

Dentistry is undergoing significant changes with need for the dentist to manage a larger body of knowledge and information. There will be increasing reliance on electronic information systems in education, research, and dental practice. Dental informatics is concerned with computer and information science and technology and communications. Goals, that could be adopted for Australia, were proposed in the USA in 1989. Specific action steps that could meet those goals are proposed for Australia.