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Marginal Defects (marginal + defect)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Augmentation of Exposed Implant Threads with Autogenous Bone Chips: Prospective Clinical Study

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2000
Göran Widmark DDS
ABSTRACT Background: Autogenous bone chips can be harvested during drilling of implant sites and may be used as a graft material for bone augmentation and coverage of exposed implant threads. Purpose: The aim of this prospective study was to evaluate the possibility of augmenting exposed implant threads with autogenous bone chips. Materials and Methods: Twenty-one consecutive patients treated with screw-shaped oral implants with exposed threads due to buccal fenestration or marginal defects were augmented with autogenous bone harvested with a bone trap during drilling of the implant site. Both marginal (9 sites) and fenestration defects (12 sites), with 4 to 14 exposed implant threads, were registered clinically and with photography. The number of exposed implant threads was measured before and at second-stage surgery 6 months after augmentation. Results: Complete bone coverage of the exposed implant threads was seen in 12 of the 21 implant sites. Six sites showed one to two remaining exposed threads, two showed about 40% coverage, and one showed flattening of the defect but with eight of nine exposed threads at 6 months follow-up. The mean bone gain was 81% in patients with a marginal defect and 82% in patients with a fenestration defect. Conclusion: The results from this clinical study show that it is possible to gain bone over exposed implant threads by augmentation with autogenous bone chips. Conclusion It is concluded that it is possible to achieve coverage of exposed implant threads by augmentation with autogenous bone chips harvested during drilling of implant sites. [source]

Detection of marginal defects of composite restorations with conventional and digital radiographs

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2002
Rainer Haak
The purpose of this study was to determine the validity of detecting approximal imperfections of composite fillings using three intraoral radiographic systems in vitro. Class II composite resin restorations (108) with three radiopacities (264, 306, 443% Al 99.5) of which 27 had marginal openings or overhangs, respectively, were conventionally (Ektaspeed plus) and digitally (Dexis, Digora) radiographed. Images were assessed by 10 observers for the presence of marginal gaps and overhangs, as well as for their need of restorative treatment according to a five-point confidence rating scale. The validity of the observations were expressed as areas under receiver operating characteristic (ROC) curves (Aroc). Repeated measures analysis of variance revealed significant effects of ,radiographic system' and ,diagnostic purpose'. Marginal overhangs (Aroc = 0.90) were significantly easier to diagnose than openings (Aroc = 0.63). Marginal gaps were better detected on conventional and Dexis radiographs than on Digora images. the range of sensitivities and specificities of the treatment decision was 0.53,0.56 and 0.87,0.88, respectively. It was concluded that the validity of detecting marginal defects of composite resin restorations based on radiographs was only slightly affected by the radiographic system being used. The diagnosis of marginal gaps frequently resulted in false-positive and false-negative decisions. [source]

Augmentation of Exposed Implant Threads with Autogenous Bone Chips: Prospective Clinical Study

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2000
Göran Widmark DDS
ABSTRACT Background: Autogenous bone chips can be harvested during drilling of implant sites and may be used as a graft material for bone augmentation and coverage of exposed implant threads. Purpose: The aim of this prospective study was to evaluate the possibility of augmenting exposed implant threads with autogenous bone chips. Materials and Methods: Twenty-one consecutive patients treated with screw-shaped oral implants with exposed threads due to buccal fenestration or marginal defects were augmented with autogenous bone harvested with a bone trap during drilling of the implant site. Both marginal (9 sites) and fenestration defects (12 sites), with 4 to 14 exposed implant threads, were registered clinically and with photography. The number of exposed implant threads was measured before and at second-stage surgery 6 months after augmentation. Results: Complete bone coverage of the exposed implant threads was seen in 12 of the 21 implant sites. Six sites showed one to two remaining exposed threads, two showed about 40% coverage, and one showed flattening of the defect but with eight of nine exposed threads at 6 months follow-up. The mean bone gain was 81% in patients with a marginal defect and 82% in patients with a fenestration defect. Conclusion: The results from this clinical study show that it is possible to gain bone over exposed implant threads by augmentation with autogenous bone chips. Conclusion It is concluded that it is possible to achieve coverage of exposed implant threads by augmentation with autogenous bone chips harvested during drilling of implant sites. [source]

A prospective clinical study of non-submerged immediate implants: clinical outcomes and esthetic results

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2007
Stephen T. Chen
Abstract Objectives: To evaluate healing of marginal defects in immediate transmucosal implants grafted with anorganic bovine bone, and to assess mucosal and radiographic outcomes 3,4 years following restoration. Material and methods: Thirty immediate transmucosal implants in maxillary anterior extraction sites of 30 patients randomly received BioOssÔ (N=10; BG), BioOssÔ and resorbable collagen membrane (N=10; BG+M) or no graft (N=10; control). Results: Vertical defect height (VDH) reductions of 81.2±5%, 70.5±17.4% and 68.2±16.6%, and horizontal defect depth (HDD) reductions of 71.7±34.3%, 81.7±33.7% and 55±28.4% were observed for BG, BG+M and control groups, respectively, with no significant inter-group differences. Horizontal resorption was significantly greater in control group (48.3±9.5%) when compared with BG (15.8±16.9%) and BG+M (20±21.9%) groups (P=0.000). Ten sites (33.3%) exhibited recession of the mucosa after 6 months; eight (26.7%) had an unsatisfactory esthetic result post-restoration due to recession. Mucosal recession was significantly associated (P=0.032) with buccally positioned implants (HDD 1.1±0.3 mm) when compared with lingually positioned implants (HDD 2.3±0.6 mm). In 19 patients followed for a mean of 4.0±0.7 years, marginal mucosa and bone levels remained stable following restoration. Conclusion: BioOssÔ significantly reduced horizontal resorption of buccal bone. There is a risk of mucosal recession and adverse soft tissue esthetics with immediate implant placement. However, this risk may be reduced by avoiding a buccal position of the implant in the extraction socket. [source]