Acidogenic fermentation of pentose alcohols by human dental plaque microorganisms.

The potential non-cariogenicity of the pentose sugar alcohols xylitol, l-arabinitol and ribitol was estimated by determining their fermenting properties with 50 separate samples of dental plaque, collected from people of different ages. Sucrose and control cultures were included for comparison. For most subjects, sucrose was more acidogenic than the pentitols. Lactobacilli or propionibacteria which fermented xylitol were isolated in pure culture from 2 out of 50 plaque samples whereas lactobacilli which fermented l-arabinitol were purified from another. Tests were made for pentitol metabolism by saliva collected from 8 subjects: 3 carried lactobacilli or propionibacteria which fermented xylitol and at least 2 contained lactobacilli that used l-arabinitol anaerobically. Candida albicans isolated from 2 subjects metabolized xylitol aerobically. Thus xylitol-utilizing oral microorganisms may be widespread. Further research is desirable before encouraging the widespread substitution of xylitol for sucrose.     

Histometric analysis of interradicular bone in protein deficient animals

A histometric analysis of bone density was made in the interradicular bone of rats fed either a powdered protein free diet, pair-fed with an isocaloric 27 % casein diet or fed control diets, ad libitum, of either soft or hard consistencies. A marked osteoporosis was found in the two nutritionally restricted groups. The pair fed animals showed a greater osteoporosis than the protein deficient animals. These results were statistically significant (p = 0.001).     

Clinical evaluation of the Carisolv chemomechanical caries removal technique according to the site/stage concept,a revised caries classification system

The objective of the present study was to assess the efficiency and benefit of a chemomechanical system for carious dentin removal, Carisolv, in general practice. A revised caries classification, the site/stage concept, was used to describe the clinical situations of all carious lesions treated. The study was performed by 12 investigators, and 120 carious lesions were treated with Carisolv. Sixty percent of the cases were treated without anaesthesia, and we found a significant correlation between chemomechanical treatment without anaesthesia and absence of pain ( P=0.01). In 78.3% of the cases, carious dentin was totally removed with Carisolv, and in 21.7%, the dentin treatment was completed by drilling. In cases performed with Carisolv alone, the time required to remove carious dentin was 11.1+/-9.51 min (mean+/-SD). Treatment time was equivalent for all sites and increased significantly with each successive stage of lesion progression ( P<0.001). In 82.5% of cases, the clinicians were satisfied with Carisolv, and in 99.2%, so were the patients. We conclude that, using clinical examination methods, Carisolv seems to remove carious dentin at all sites and stages of carious lesions but must be made more efficient for use in general practice.     

Immunolocalization of a human cementoblastoma-conditioned medium-derived protein

Little is known about the molecular mechanisms that regulate the cementogenesis process, because specific cementum markers are not yet available. To investigate whether a cementoblastoma-conditioned medium-derived protein (CP) could be useful as a cementum biological marker, we studied its expression and distribution in human periodontal tissues, human periodontal ligament, alveolar bone, and cementoblastoma-derived cells. In human periodontal tissues, immunoreactivity to anti-CP was observed throughout the cementoid phase of acellular and cellular cementum, cementoblasts, cementocytes, cells located in the endosteal spaces of human alveolar bone, and in cells in the periodontal ligament located near the blood vessels. Immunopurified CP promoted cell attachment on human periodontal ligament, alveolar bone-derived cells, and gingival fibroblasts. A monoclonal antibody against bovine cementum attachment protein (CAP) cross-reacted with CP. These findings indicate that CP identifies potential cementoblast progenitor cells, is immunologically related to CAP species, and serves as a biological marker for cementum.     

Dentine bonding agents--a review of adhesion to dentine.

Although constant innovation has improved the performance of dentine adhesives, the true mechanism of resin adhesion to dentine is still not clear and the optimal dentinal surface pretreatment has yet to be determined for adhesive integrity of resin to dentine. The integrity of the collagen fibrils left exposed upon acid etching seem to play a major role in the mechanism of adhesion and intermingling of the adhesive monomers with the filigree of collagen fibers or hybrid layer should be considered the paramount dentine bonding mechanism. Definite trends are emerging but more research is necessary before general conclusions can be made about the functions of different bonding agents. The all-in-one self-etching/self-primer bottle systems are relatively new to the market and need more research before they can be advocated as the agent of choice.