Tricho-dento-osseous syndrome: a scanning electron microscopic analysis.

A large kindred of which multiple members have the Tricho-dento-osseous syndrome is presented. This is an autosomal dominant disorder characterized by defective enamel, taurodontia, unusually curly hair and occasionally mild to moderate skeletal osteosclerosis. Histologic investigation of teeth (by both LM and SEM) demonstrated that there is a uniformly thin enamel covering with randomly distributed depression and pits. The mineral content of this enamel is closer to that of the underlying dentin, which accounts for its lack of radiographic contrast. The dentin was normal. A bizarre finding is that of a periradicular sheath or membrane that enclosed the open apices and extended partway up the root. It was composed of collagen fiber bundles. The anatomical position of this membrane suggested that it may represent the developing peridontal ligament seen in early tooth formation. Recent embryologic evidence provides support for mesenchymal culpability for all reported features of the syndrome.

Effect of cobalt-60 radiation on the pulp of restored teeth.

The effect of cobalt-60 teletherapy on the pulps of restored teeth of monkeys was studied. Gold crowns and amalgam and composite resin restorations were placed in 28 teeth of two Macaca speciosa monkeys. One monkey then received cobalt-60 radiation to both maxillary and mandibular teeth and bones, with a total dose of 7,600 rads. Decalcified semiserial paraffin sections, 7 mum thick, of the teeth and supporting tissues were prepared and stained with hematoxylin and eosin. Microscopically, there was no discernible difference between the irradiated and the non-irradiated pulps.

Long-term study of pulp capping in monkeys with three agents.

The pulps of 40 permanent teeth of two monkeys were mechanically exposed and contaminated with adjacent saliva or plaque for 3 to 5 1/2 hours. The pulps were then capped with either Keflin (an antibiotic), Durelon (a polycarboxylate cement), or Dycal (a calcium hydroxide compound). Varnish and then amalgam were inserted. Each monkey received at least one dose of Procion red H-8BS vital dye. The teeth were extracted from one monkey 23 months after capping and from the other monkey 29 months after capping. Serial, decalcified, 7 mum-thick paraffin sections were prepared. Alternate slides were stained with hematoxylin ane eosin. Unstained sections were examined for Procion labeling, and selected slides were stained by the Brown-Brenn method for bacteria. Of 13 teeth capped with Keflin, only 4 responded satisfactorily. All of the Dycal and Durelon-capped pulps were successful at both time intervals. All of the Dycal-capped pulps showed complete bridging and no inflammation or pulp obliteration. Bridging was complete in only three of the Durelon-capped pulps. The findings of this study support the findings in our previous study3 and further substantiate the effectiveness of Dycal as a pulp-capping agent. The often-repeated claim that calcium hydroxide compounds exert a persistent stimulating effect on the pulp resulting in its eventual obliteration was not supported. Durelon is not recommended for pulp capping since the material apparently lacks an antibacterial effect and does not stimulate reparative dentinogenesis at the exposure site. The low rate of satisfactory responses of pulps capped with Keflin, as used, precludes its use of pulp capping.

Clinical, radiographic, and histological study of endodontically treated retained roots to preserve alveolar bone.

Endodontically treated, submerged roots in two Macaca speciosa monkeys were studied clinically, radiographically, and histologically. The roots were successfully covered by soft tissue, except in two areas. In several sites, radiographic evidence of bone formation was observed; this was confirmed by histologic examination. Bone formation coronal to the submerged roots was not a predictable occurrence. Even though epithelium and inflammation commonly occurred over the amputation sites, their presence did not seem to affect bone formation.

The clinical and histological response of periodontal pockets to root planing and oral hygiene.

The study evaluated, clinically and microscopically, the soft tissue response of suprabony periodontal pockets treated by root planing and oral hygiene or by oral hygiene measures alone. The participants were 22 adults beginning treatment for inflammatory periodontal disease. For each patient, three clinically similar labial or lingual pockets were scored for gingival inflammation, pocket depth, and the extent of plaque and calculus. One pocket in each patient served as a control, and a gingival biopsy was obtained to determine the pretreatment level of inflammation. The second pocket was treated by root planing and by the patient's oral hygiene measures. The third pocket was treated only by the patient's daily oral hygiene measures. Fifty-six to 63 days later, treated areas were reevaluated clinically, and biopsies were secured. Each type of therapy reduced the mean pocket depth and the incidence and severity of gingivitis; however, root planing accompanied by oral hygiene measures resulted in a statistically greater improvement than did oral hygiene measures alone.