Sterilisation of extracted human teeth for educational use.

Sixty intact, non-carious and unrestored teeth extracted due to periodontal disease were used to determine the most effective method of sterilisation. The teeth were divided into six groups, each containing 10 teeth. Group 1 teeth were immersed in 10% formalin for seven days, group 2 teeth were immersed in 3% hydrogen peroxide for seven days, group 3 teeth were immersed in 2.6% sodium hypochlorite for seven days, group 4 teeth were boiled in water at 100 degrees C for 20 minutes, group 5 teeth were autoclaved at 121 degrees C at 15 lbs psi for 30 minutes, and group 6 teeth were immersed in normal saline for seven days. After the treatment, the teeth were individually inoculated into trypticase soy broth and incubated for 48 hours. A questionnaire survey was also conducted to determine the awareness of dental students regarding infection due to extracted human teeth and the common disinfection/sterilisation methods used. Autoclaving at 121 degrees C, 15 lbs psi for 30 minutes and immersion in 10% formalin for seven days were effective in disinfecting/sterilising extracted human teeth. Chemicals such as 2.6% sodium hypochlorite, 3% hydrogen peroxide and boiling in water were not effective. The results indicate that autoclaving for 30 minutes or immersion in 10% formalin for seven days could be effectively used for disinfection/sterilisation of extracted human teeth.

Loss of deciduous teeth and germs of permanent incisors in a 4-year-old child. An atypic prepubertal periodontitis? A clinical, microbiological, immunological and ultrastructural study.

A 4-year-old child was referred, in April 1988, to Rennes Dental School (France) for deciduous tooth mobility with premature loss of 4 deciduous teeth and germs of 2 permanent incisors. Microbiological examinations by culture revealed the presence of the periodontal pathogen Actinobacillus actinomycetemcomitans. Immunofluorescence of plaque samples revealed the presence of Porphyromonas gingivalis that had not been isolated by culture. Neutrophil functions were within normal ranges. Transmission electron microscopy of gingiva showed a disorganised epithelium. The connective tissue was infiltrated by inflammatory cells. The basement membranes were normal, but the connective tissue-epithelium interface was mainly composed of short rete pegs. Scanning electron microscopy of extracted deciduous teeth revealed lack of cementum, lacunae in the cementum and lack of fibrillar insertion on the middle part of the root. Skin lesions, mainly situated on face, were observed. Treatment was by extraction of mobile deciduous teeth combined with 3-week courses of metronidazole. Clinical and microbiological follow-up was continued over a 7-year period. No periodontal lesions have been detected since eruption of the permanent teeth. The present subgingival and lingual microflora (December 1995) is composed of bacteria associated with periodontal health. However, the future appearance of a hitherto undetected systemic disease is still possible.

Can the presence of erupting or exfoliating teeth increase the salivary lactobacillus count?

The salivary lactobacillus count was assessed during school attendance among 1734 7-15-yr-old children and related to the number of teeth erupting within each age group. The prevalence of extremely low lactobacillus counts (less than or equal to 10(3)) was inversely correlated with the number of erupting teeth (P less than 0.001) but the differences were small. High counts differed only by 7% between ages with the lowest and the highest mean number of erupting or exfoliating teeth tend to elevate the lactobacillus count in individuals. On a population level the effect is small.

Laboratory studies of a family manifesting premature exfoliation of deciduous teeth.

In a previous publication, we described the clinical and radiographic findings of a family in which the children manifested premature exfoliation of the deciduous teeth. We now report for the same family the results of extensive laboratory studies performed on blood and urine, analysis of periodontal microflora, and a family pedigree. We demonstrated the presence of putative periodontal pathogens in the subgingival microflora, elevated levels of serum antibodies reacting to Bacteroides gingivalis, Capnocytophaga gingivalis, and C. sputigena in 2 of the children, and significantly suppressed monocyte chemotaxis in all 3 children. Phosphoethanolamine was found in the urine of the father and all 3 children, but not in the mother. Likewise, serum alkaline phosphatase was abnormally low for all 3 children, and was at the extreme low end of normal range for the father, but was normal for the mother. On the basis of the alkaline phosphatase and phosphoethanolamine measurements, we assigned a diagnosis of hypophosphatasia to the 3 children. Phosphoethanolamine and alkaline phosphatase were also abnormal in the paternal grandmother and her brother. The son of this brother who was deceased had a daughter manifesting premature loss of the primary teeth. The data are consistent with an autosomal dominant mode of transmission. In the light of our findings, hypoplastic cementum must be considered in the etiology of some forms of early-onset periodontitis.