Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been assumed that dentin adhesives can prevent root surface caries. The aim of this study was to determine the caries-protective effect of two different dentin bonding systems on the demineralization of root surfaces in vitro. The root surfaces of 60 freshly extracted caries-free human molars were thoroughly cleaned and polished, thereby removing the cementum. The teeth were then coated with acid-resistant nail varnish, exposing two rectangular windows of 6 mm2 each. One window served as an untreated control, while the other window was treated with a dentin bonding system. The specimens were distributed among the following experimental groups--Group 1: Syntac, Heliobond (no air thinning); Group 2: Syntac, Heliobond (as recommended); Group 3: Syntac, without Heliobond; Group 4: Prime & Bond 2.0 (no air drying); Group 5: Prime & Bond 2.0 (as recommended); Group 6: Prime & Bond 2.0 (dentin pretreated with 36% phosphoric acid). Subsequently, all specimens were demineralized for 6 days with acidified gel (HEC, pH 4.8, 37 degrees C). From each tooth, three dentinal slabs were cut perpendicular to the polished surface of the windows. The slabs were ground to a thickness of 80 microns and imbibed with water. The depth of the respective demineralized areas was determined using a polarized light microscope. All control specimens exhibited lesions with a mean depth of 67 microns. In Groups 2, 3, and 5 the lesion depth was reduced significantly, while in Groups 1, 4, and 6 no lesions could be detected. It was concluded that the demineralization of the root surface can be impeded by application of the dentin adhesives tested.
 ...
PMID:Influence of two dentin bonding systems on the demineralization of the root surface. 1082 83

Recently several long-term studies have reported evidence of the hydrolytic degradation of collagen fibrils based on fractured surface observations after bond testing. Those studies suggested that one cause of the decline in the bond strength was the degradation of the collagen fibrils within the bonds. However, one concern has been raised that the dentinal collagen fibrils may be stable in water that does not contain oral bacteria or enzymes. Therefore, the present study aimed to clarify the micromorphological change in naked collagen fibrils after 500 days of water storage. To prepare exposed collagen fibrils, sectioned and polished human dentin surfaces were acid conditioned for 15 s with the use of two commercially available acid conditioners: All-Etch (10% phosphoric acid) and Uni-Etch (32% phosphoric acid) (Bisco, Inc.). Those specimens were stored in distilled water at 37 degrees C for 1 day (control) for 500 days. After the storage periods, the samples were examined with the use of SEM and TEM. Under SEM and TEM examination, micromorphological alterations (disarrangement of collagen web, widening the interfibrillar space, and the thinning diameter of collagen fibrils) were found in the specimens after 500 days in water.
 ...
PMID:SEM and TEM analysis of water degradation of human dentinal collagen. 1280 86