title: Bacterial colonization and degradation of demineralized dentin matrix in situ.
abstract: Lesion formation in dentin involves demineralization followed by degradation of the exposed organic matrix. Proteinases from microorganisms present in the dentin are believed to play an important role in the breakdown of the dentinal collagen. In this study, the microflora colonizing decalcified dentin matrix, placed in situ, was identified. The gelatinolytic activity of the isolated strains was assessed and related to the degradation of the dentin matrix. The predominant species found were Streptococcus mitis. Peptostreptococcus productus, Lactobacillus casei, Propionibacterium species and Veillonella parvula. Marked interindividual variation in the composition of the microflora was observed. The microflora possessed gelatinolytic activity, although no correlation was found with the severity of dentin matrix degradation. The chemically determined loss of collagen varied between 0 and 67 wt% per participant and corresponded with the extent of collagen degradation observed by transmission electron microscopy.
authors.affiliation: Department of Cariology and Endodontology, Academic Centre for Dentistry, Amsterdam (ACTA), The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: van Strijp
authors.forename: T J
authors.initials: TJ
authors.lastname: van Steenbergen
authors.forename: J
authors.initials: J
authors.lastname: de Graaff
authors.forename: J M
authors.initials: JM
authors.lastname: ten Cate
mesh_terms: D000818:Animals; D001419:Bacteria / Q000302:isolation & purification / Q000378:metabolism; D001422:Bacterial Adhesion; D018407:Bacterial Physiological Phenomena; D002417:Cattle; D003094:Collagen / Q000032:analysis / Q000378:metabolism; D003804:Dentin / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology* / Q000648:ultrastructure; D006801:Humans; D007778:Lactobacillus / Q000378:metabolism / Q000502:physiology; D008854:Microscopy, Electron; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000378:metabolism; D010462:Peptostreptococcus / Q000378:metabolism / Q000502:physiology; D013291:Streptococcus / Q000378:metabolism / Q000502:physiology; D017001:Tooth Demineralization / Q000378:metabolism / Q000382:microbiology* / Q000473:pathology; D014678:Veillonella / Q000378:metabolism / Q000502:physiology
chemical_list: D003094:Collagen; D010447:Peptide Hydrolases