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286


Shear bond strengths of gluma bonding systems to dentin. [Meeting Abstract]

Ritter, AV; Bertoli, C; Swift, EJ
ISI:000084937001849
ISSN: 0022-0345
CID: 4144372

Conservation of collagen cross-links during dentin acid conditioning [Meeting Abstract]

Ritter, AV; Yamauchi, M
ISI:000084937002192
ISSN: 0022-0345
CID: 4144382

Shear bond strengths of one-bottle adhesives to oil-contaminated enamel

Rosa, B T; Heymann, H O; Swift, E J; Perdigão, J; Ritter, A V
PURPOSE/OBJECTIVE:To evaluate resin bond strength to enamel contaminated with handpiece oil. MATERIALS AND METHODS/METHODS:Bovine teeth were randomly assigned to six groups of 20 teeth each for treatment with one of six different bonding systems (five one-bottle and one multibottle). For each system, 10 enamel specimens were contaminated with handpiece oil before acid-etching and 10 were contaminated after acid-etching. The enamel was etched for 15 seconds using 35% phosphoric acid. Following adhesive application, composite resin was bonded using a gelatin capsule technique. Shear bond strengths from the two contaminated groups were compared to bond strengths to uncontaminated enamel obtained from a previous study that was performed by the same group of investigators, using the same facility, materials, and methods. RESULTS:Two-way analysis of variance (ANOVA) showed that the factor "surface contamination" did not have a significant effect on bond strength (p > .542). The type of adhesive and the interaction of adhesive and surface contamination were significant (p < .0001 and p < .003, respectively). When oil was applied before etching, mean bond strengths ranged from 18.0 +/- 4.8 MPa for OptiBond SOLO (Kerr Corp., Orange, California) to 25.3 +/- 5.6 MPa for Tenure Quik with Fluoride (Den-Mat Corp., Santa Maria, California). With oil applied after etching, bond strengths ranged from 18.4 +/- 8.0 MPa for Tenure Quik with Fluoride to 27.4 +/- 5.4 MPa for Single Bond (3M Dental Products, St. Paul, Minnesota). For the same adhesive, comparing uncontaminated and "oil-before-etch" contaminated groups, the only statistically significant difference in bond strengths was for OptiBond SOLO: 21.8 +/- 4.0 MPa (uncontaminated) versus 18.0 +/- 4.8 MPa (oil before etch). Comparing uncontaminated and "oil-after-etch" groups, the only statistically significant difference was for Tenure: 24.5 +/- 5.7 MPa (uncontaminated) and 18.4 +/- 8.0 MPa (oil after etch).
PMID: 11324082
ISSN: 1040-1466
CID: 4142752

Effects of different re-wetting techniques on dentin shear bond strengths

Ritter, A V; Heymann, H O; Swift, E J; Perdigäo, J; Rosa, B T
PURPOSE/OBJECTIVE:For contemporary hydrophilic resin adhesive systems, bonding to dentin is improved if the substrate is maintained in a hydrated state following acid-etching. The purpose of this study was to compare the dentin shear bond strengths of two single-bottle adhesives (one acetone-based and one ethanol-based) applied under different etched-dentin conditions: dry, wet, or dry and re-wetted with different solutions. MATERIALS AND METHODS/METHODS:Bovine incisors (N = 120) were mounted in acrylic, polished to 600-grit, and randomly assigned to 12 groups (n = 10). Dentin was etched for 15 seconds using 35% phosphoric acid, rinsed, and either blot-dried, air-dried, or air-dried and re-wetted with different solutions (distilled water, Gluma Desensitizer, Aqua-Prep, and 5% glutaraldehyde in water). Two adhesives (Single Bond and Prime & Bond NT) were applied to each of the surface conditions following manufacturers' instructions. After adhesive application and curing, composite was applied in a No. 5 gelatin capsule and light-cured. Specimens were loaded in shear, using an Instron at 5 mm per minute. Shear bond strengths were calculated by dividing the failure load by the bonded surface area. Data were subjected to analysis of variance (ANOVA) and a post hoc Tukey test. RESULTS:Mean shear bond strengths ranged from 12.5 to 26.6 MPa for Single Bond and from 5.6 to 14.7 MPa for Prime & Bond NT. Significant differences were found in both groups of materials (p < .001). The three highest mean bond strengths were obtained (in order) on dentin that was re-wetted with Gluma Desensitizer, re-wetted with Aqua-Prep, or never dried. Differences between these surface conditions were not statistically significant for either material.
PMID: 11326508
ISSN: 1040-1466
CID: 4142762

A clinical, radiographic, and scanning electron microscope evaluation of adhesive restorations on carious dentin in primary teeth

Ribeiro, CCC; Baratieri, LN; Perdigao, J; Baratieri, NM; Ritter, Andre V
ORIGINAL:0014423
ISSN: n/a
CID: 4155532

Teaching of posterior composite resin restorations in Brazilian dental schools [Meeting Abstract]

Gordan, VV; Ritter, Andre V; Mjor, IA; Veiga-Filho, LC
ORIGINAL:0014413
ISSN: 0022-0345
CID: 4155432

A clinical, radiographic, and scanning electron microscopic evaluation of adhesive restorations on carious dentin in primary teeth

Ribeiro, C C; Baratieri, L N; Perdigão, J; Baratieri, N M; Ritter, A V
OBJECTIVE:The purpose of this project was to evaluate the performance of a dentin adhesive system on carious and noncarious primary dentin in vivo. METHOD AND MATERIALS/METHODS:Forty-eight primary molars with carious lesions were randomly assigned to 2 different treatments: group 1 (control, n = 24)--All identifiable, irreversibly infected dentin was removed prior to the application of the bonding agent and restorative material; group 2 (experimental, n = 24)--Irreversibly infected dentin was partially removed prior to the application of the bonding agent and restorative material. The control and experimental teeth were clinically monitored every 3 months and evaluated 12 months after restoration. The teeth were extracted around the time of exfoliation and processed for scanning electron microscopy. RESULTS:Retention rate, marginal integrity, and pulpal symptoms were identical in both groups. Radiographically, the radiolucent area associated with the experimental restorations did not increase with time in 75% of the cases. For the control group, the adhesive system formed a hybrid layer. In the experimental group, there was morphologic evidence of the formation of an acid-resistant "altered hybrid layer." An acid-resistant tissue, resulting from the interdiffusion of adhesive resin within the area of carious dentin, was observed adjacent to and under the altered hybrid layer. CONCLUSION/CONCLUSIONS:Application of an adhesive restorative system to irreversibly infected dentin did not affect the clinical performance of the restoration.
PMID: 10765864
ISSN: 0033-6572
CID: 4142712

The effect of finishing and polishing on the decision to replace existing amalgam restorations

Cardoso, M; Baratieri, L N; Ritter, A V
OBJECTIVE:The purpose of this investigation was to evaluate the influence of finishing and polishing procedures on the decision to replace existing amalgam restorations. METHOD AND MATERIALS/METHODS:Twenty Class I and Class II amalgam restorations, free from obvious defects, were selected in 6 patients. The restorations were photographed before and after being submitted to a standard finishing and polishing procedure. In the first phase, the preoperative slides were examined by 27 clinicians and senior dental students, who were instructed to inspect each restoration and answer a questionnaire indicating if and why the restoration needed to be replaced. Two weeks later, the postoperative slides were presented to the same examiners, who were asked to answer the same questionnaire as before. RESULTS:At the first phase, there were 236 decisions (44%) to replace existing amalgam restorations. Following the finishing and polishing procedures, 114 decisions (21%) were made to replace existing amalgam restorations. This difference was statistically significant. Secondary caries was the most common reason for replacement. CONCLUSION/CONCLUSIONS:The finishing and polishing procedure reversed the decision to replace old amalgam restorations.
PMID: 10635277
ISSN: 0033-6572
CID: 4142702

Enamel phenotype in three families with amelogin gene point mutation [Meeting Abstract]

Ravassipour, DB; Hart, S; Hart, TC; Ritter, Andre V; Yamauchi, M; Gibson, C; Wright, JT
ORIGINAL:0014419
ISSN: 0022-0345
CID: 4155492

Ceramic restorations for posterior teeth: guidelines for the clinician

Ritter, A V; Baratieri, L N
UNLABELLED:Metal-free ceramic restorations are increasingly popular for restoring posterior teeth. These restorations are generated through a variety of techniques (e.g., CAD-CAM, copy-milling, heat-pressing, and firing). When appropriately indicated and made, ceramic inlays or onlays can be reliable and provide a highly serviceable restoration. The aim of this article is to review and present updated information regarding indications, restorative technique, and maintenance for this class of restorations, with emphasis to fired ceramic inlays or onlays. The information presented is based on 15 years of controlled clinical experience with this category of restorations. Clinical cases that represent some applications also are presented. CLINICAL SIGNIFICANCE/CONCLUSIONS:The fired ceramic inlay/onlay technique is presented as a viable option for the esthetic and adhesive restoration of posterior teeth.
PMID: 10530270
ISSN: 1040-1466
CID: 4142682