Biomedical subjects

Barbara Boyan

Publications and source records attributed to Barbara Boyan.

2 recordsLinked to original sources

PubMed2005

Differential regulation of osteoblasts by substrate microstructural features.

Microtextured titanium implant surfaces enhance bone formation in vivo and osteoblast phenotypic expression in vitro, but the mechanisms are not understood. To determine the roles of specific microarchitectural features in modulating osteoblast behavior, we used Ti surfaces prepared by electrochemical micromachining as substrates for MG63 osteoblast-like cell culture. Cell response was compared to tissue culture plastic, a sand-blasted with large grit and acid-etched surface with defined mixed microtopography (SLA), polished Ti surfaces, and polished surfaces electrochemically machined through a photoresist pattern to produce cavities with 100, 30 and 10 microm diameters arranged so that the ratio of the microscopic-scale area of the cavities versus the microscopic-scale area of the flat region between the cavities was equal to 1 or 6. Microstructured disks were acid-etched, producing overall sub-micron-scale roughness (Ra=0.7 microm). Cell number, differentiation (alkaline phosphatase; osteocalcin) and local factor levels (TGF-beta1; PGE(2)) varied with microarchitecture. 100 microm cavities favored osteoblast attachment and growth, the sub-micron-scale etch enhanced differentiation and TGF-beta1 production, whereas PGE(2) depended on cavity dimensions but not the sub-micron-scale roughness.

Biocompatible Materials↗

PubMed2002

Coverage of carious roots by a subepithelial connective tissue graft.

PURPOSE: To assess whether coverage of an untreated or restored carious root lesion with a subepithelial connective tissue graft would provide a predictable, esthetically acceptable result and prevent further caries progression. MATERIALS AND METHODS: Twenty-seven teeth from 13 patients with root caries and gingival recessions of 3.4 +/- 0.2 mm (mean +/- SEM) were treated with subepithelial connective tissue grafts. Eighteen teeth had untreated caries, and the other nine had composite or glass-ionomer restorations. The carious dentin and the plastic restorations were removed prior to the surgical procedure. The exposed roots were thoroughly planed and covered by a subepithelial connective graft with no further root treatment or conditioning. The teeth were examined periodically from 1-6 years post-treatment for retention of root surface coverage and presence of carious lesions. RESULTS: The mean root coverage recession left after the treatment was 0.3 +/- 0.1 mm, with coverage of 92.4 +/- 2.4%. Significant differences (P< 0.05) were found between the coverage of roots with carious lesions that had not been restored and those that had restorations removed. However, since the number of teeth with restorations was limited, further study is required to confirm this difference. In 18 cases, complete coverage of the recession was achieved. The results were stable, and no further recessions or recurrent caries were detected.

Adult↗