Biomedical subjects

L N Baratieri

Publications and source records attributed to L N Baratieri.

At least 19 recordsLinked to original sources

PubMed2001

Four-year clinical evaluation of posterior resin-based composite restorations placed using the total-etch technique.

PURPOSE: To report the 4-year clinical performance of posterior resin-based composite restorations placed using the total-etch technique. MATERIALS AND METHODS: Over a period of 1 year, 726 restorations (248 molars, 478 premolars; 260 Class I, 466 Class II; 540 replacements, 186 primary decay) were placed on conservative preparations, using the incremental placement technique in a clinical environment. Baseline data were collected, and the restorations were evaluated after 4 years. Z100 and Scotchbond Multi-Purpose (SBMP) (3M Dental Products, St. Paul, Minnesota) were used as the restorative system. The criteria evaluated were color match, marginal adaptation, anatomic form, cavosurface marginal discoloration, axial contour, interproximal contact, secondary caries, postoperative sensitivity, and tooth vitality. RESULTS: At baseline, 24% of the teeth restored presented postoperative sensitivity; 86% of the sensitive teeth were from the replacement group. At 4 years, all teeth were vital to cold test. Eighteen restorations (2.5%) presented clinically detectable marginal fracture. The shade was acceptable in all restorations. Cavosurface marginal discoloration was observed in 47 restorations (6.5% bravo scores). Axial contour, interproximal contact, and marginal adaptation received 100% alfa scores. No secondary caries was diagnosed in any of the teeth examined. None of the examined restorations required replacement. CLINICAL SIGNIFICANCE: Under controlled clinical conditions, posterior resin-based composite restorations placed with the total-etch technique and restorative Z100/SBMP have the potential to present a high success rate at 4 years. None of the examined restorations required replacement, and there was no clinically detectable wear in any of the restorations. Simultaneous etching of enamel and dentin followed by the application of a resin adhesive can be considered an adequate modality of pulp protection in nonexposed tooth preparations.

Acid Etching, Dental↗

PubMed2001

All-ceramic post core, and crown: technique and case report.

UNLABELLED: The functional and esthetic restoration of severely compromised anterior teeth is a challenge to clinicians in their daily practice. The duplication of the optical characteristics of an intact tooth, including shade, translucency, and fluorescence, is often made difficult by the use of metal infrastructures, such as post-and-cores and copings. The development of reinforced ceramics and non-metallic post systems made possible the generation of metal-free ceramic restorations in severely compromised anterior and posterior teeth. This article discusses one available technique for the generation of a single all-ceramic restoration involving the use of a zirconia- or leucite-reinforced post-and-core system and of an all-ceramic crown system. A representative clinical case is presented illustrating the potential of the technique. CLINICAL SIGNIFICANCE: Modern ceramic restorative systems offer the possibility to closely match the natural optical characteristics of lost tooth structure. Posts, cores, and copings fabricated in ceramic materials represent a promising alternative to metals in the restoration of severely compromised anterior teeth.

Adult↗

PubMed2000

Influence of post placement in the fracture resistance of endodontically treated incisors veneered with direct composite.

STATEMENT OF PROBLEM: Veneer preparations are considered to weaken endodontically treated maxillary incisors. Prefabricated posts have been controversially indicated to reinforce endodontically treated teeth before final restoration. PURPOSE: This in vitro study evaluated whether (1) veneer preparation in enamel or in enamel/dentin weakens endodontically treated maxillary incisors, (2) bonding of direct composite veneer restores the original strength of the unprepared teeth, and (3) use of prefabricated metal posts increases fracture resistance of prepared and restored teeth. MATERIAL AND METHODS: Ninety extracted human maxillary central incisors were submitted to conventional root canal treatment. Specimens were randomly divided into 8 experimental groups (veneer preparation in enamel or dentin with/without post and with/without direct composite veneer restoration) and a control group (n = 10). Specimens were loaded to fracture, and the data were analyzed statistically. RESULTS: Statistical analysis revealed that a conservative veneer preparation does not significantly reduce maxillary incisors' fracture resistance. For prepared incisors, bonding of direct composite veneer restored their original strength, and the use of posts did not increase their fracture resistance. CONCLUSION: Conservative veneer preparations involving enamel and enamel/dentin did not significantly reduce the fracture resistance of endodontically treated maxillary incisors. In addition, restoration of the intraenamel preparations with direct composite resulted in teeth more resistant to fracture than teeth having restorations in dentin. The use of posts did not improve fracture resistance of endodontically treated maxillary incisors reduced and veneered with direct composite.

Analysis of Variance↗

PubMed2000

Direct resin composite veneers: masking the dark prepared enamel surface.

A technique for manufacturing direct resin composite veneers is presented. Described are the advantages of using an acrylic resin matrix, made before the preparation is begun, to copy anatomic details. An additional step to mask previously prepared dark enamel with opaquers is also described. The advantages and limitations of the procedures are discussed.

Composite Resins↗

PubMed1999

Laboratory evaluation and clinical application of a new one-bottle adhesive.

PURPOSE: The purposes of this project were to compare the enamel and dentin bond strengths of a new nanofilled one-coat adhesive system with its predecessor, an unfilled two-coat adhesive system; to analyze the dentin interfacial ultramorphology, using scanning and transmission electron microscopy (SEM and TEM); and to illustrate the clinical technique associated with the use of the new nanofilled one-coat adhesive system. MATERIAL AND METHODS: Twenty flat dentin surfaces and 20 flat enamel surfaces were polished on the labial surface of bovine incisors mounted in acrylic resin. The specimens were equally and randomly assigned to four bonding groups: (1) dentin with Prime & Bond 2.1; (2) dentin with Prime & Bond NT; (3) enamel with Prime & Bond 2.1; and (4) enamel with Prime & Bond NT. A composite post was then adapted to the treated area and light-cured. After thermocycling, shear bond strengths were determined by testing the shear strength of the specimens. The data were analyzed using one-way analysis of variance (ANOVA) and Student's t-test. For SEM and TEM, six dentin disks were obtained from middle dentin of human third molars and assigned equally to each adhesive. The adhesives were applied to dentin according to manufacturer's directions. The hybrid layer and resin penetration into dentin tubules were analyzed at an ultramorphologic level, and the observations were compared. RESULTS: Shear bond strengths were as follows: group 1: 17.8 +/- 4.1 MPa; group 2: 20.5 +/- 3.5 MPa; group 3: 24.7 +/- 6.7 MPa; and group 4; 27.0 +/- 5.4 MPa. Electron microscopy showed that both adhesives penetrated the dentin tubules and formed a fully infiltrated hybrid layer. The nanofiller included in the new one-application adhesive penetrated the dentin tubules and infiltrated the microspaces between the collagen fibers within the hybrid layer. CLINICAL SIGNIFICANCE: The new one-application nanofilled adhesive tested in this study resulted in bond strengths and dentin hybridization comparable to those obtained with the corresponding two-application system. The clinical sequences presented illustrate the ease of use of the newest simplified adhesives.

Adhesives↗

PubMed1999

Ceramic restorations for posterior teeth: guidelines for the clinician.

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: The fired ceramic inlay/onlay technique is presented as a viable option for the esthetic and adhesive restoration of posterior teeth.

Bicuspid↗

PubMed1999

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

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: 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: The finishing and polishing procedure reversed the decision to replace old amalgam restorations.

Chi-Square Distribution↗

PubMed1999

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

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: 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: Application of an adhesive restorative system to irreversibly infected dentin did not affect the clinical performance of the restoration.

Child↗

PubMed1998

Direct posterior composite resin restorations: current concepts for the technique.

Due to the development of sound clinical procedures and evolution of advanced restorative materials, composite resins are being used with increasing frequency for direct posterior applications. When the clinical protocol for the use of composite resin is performed properly, this material can be utilized with success and predictability. This article presents the advantages and limitations of this restorative modality. It also reviews the characteristics of contemporary composite resin materials and demonstrates the treatment protocol that is utilized to achieve aesthetic restorations in the posterior segment.

Acid Etching, Dental↗

PubMed1998

The use of liners under amalgam restorations: an in vitro study on marginal leakage.

OBJECTIVE: Marginal leakage of amalgam restorations may lead to secondary caries and pulpal damage. The purpose of this study was to determine the effect various cavity liners might have on microleakage. METHOD AND MATERIALS: Mesio-occlusodistal amalgam restorations with margins on enamel and dentin were treated with different liner materials (an adhesive system, a topical fluoride gel, a cavity varnish, and a glass-ionomer cement) in vitro. Following restoration, the teeth were submitted to thermocycling in a stained solution and sectioned to allow assessment of microleakage. RESULTS: On enamel, the control group (no liner) and the glass-ionomer-lined group had equivalent leakage scores and were superior to every other group. On dentin, only the glass-ionomer specimens had superior performance. The cavity varnish and fluoride-lined specimens exhibited the highest leakage scores. CONCLUSION: The use of liners does not reduce microleakage on amalgam restorations when the cavity margins remain on enamel. On dentin margins, a glass-ionomer liner can reduce microleakage.

Adhesives↗

PubMed1996

Posterior resin composite restorations: a new technique.

A new technique for the performance of resin composite direct restorations on posterior teeth is presented. A clear acrylic resin matrix, fabricated prior to the preparation of the occlusal and proximal surfaces, is employed. The matrix allows the fast and accurate reproduction of the anatomic details from the original occlusal surface of the tooth, as well as the marginal ridges in the case of Class II (occlusoproximal) restorations. Advantages and limitations of the procedure are discussed.

Acrylic Resins↗

PubMed1996

Influence of finishing and polishing procedures on the decision to replace old amalgam restorations: an in vitro study.

The purpose of this study was to establish the influence that finishing and polishing of existing amalgam restorations might have on the decision to replace them. Forty extracted teeth, in which amalgam restorations had been placed in vivo, were individually examined by 60 practitioners and students prior to and following standard finishing and polishing procedures. Examiners, who had not been informed of the study's methodology or objective, opted either for maintaining or replacing the restoration in question. The main reasons for replacement were also registered. Finishing and polishing significantly reduced the number of decisions to replace restorations in all groups and for all practitioners. "Appearance" (anatomic shape) was the most frequently cited reason for replacing restorations before finishing and polishing, followed by marginal defects and secondary caries.

Dental Amalgam↗

PubMed1995

Nonvital tooth bleaching: guidelines for the clinician.

The combination of intracoronal and extracoronal bleaching represents a conservative treatment to restore esthetics to darkened or stained nonvital teeth. Notwithstanding the eventual risks and difficulties accompanying such technique, nonvital teeth often can be successfully lightened. This article presents a few guidelines for bleaching nonvital teeth as well as a clinical case to illustrate the indications and clinical protocol for the technique.

Clinical Protocols↗

PubMed1994

Influence of acid type (phosphoric or maleic) on the retention of pit and fissure sealant: an in vivo study.

Two hundred twenty permanent young molars in 60 children aged 8 to 13 years received only one application of a light-activated resinous sealant. The retention rate was assessed 6 and 12 months later. The teeth were divided into 2 groups of 110 each. In one of the groups the pits and fissures were etched with 37% phosphoric acid before being sealed (group 1); in the other (group 2) these areas were etched with 10% maleic acid. The retention rate of group 1 was 98.4% at 6 months, and 96.8% at 12 months. Group 2 had retention rates of 97.5% at 6 months and 95% at 12 months. There was no statistically significant difference between the two groups in the two test periods, nor were there differences in the same group at the different periods.

Acid Etching, Dental↗

PubMed1994

Clinical evaluation of composite resin tunnel restorations on primary molars.

Twenty children, presenting 66 proximal carious lesions in 60 primary molars, were selected to receive composite resin tunnel restorations. Thirty of these teeth were expected to exfoliate within 6 months (group I); in the remaining 30 teeth exfoliation was expected within 1 year (group II). All teeth received tunnel preparations, which were then restored with a posterior composite resin. The restorations were evaluated after 6 months and after 1 year through each of the following methods: bitewing radiographic examination, clinical examination with a probe and mirror, and direct examination of proximal surfaces after tooth extraction. The occlusal portions of the restorations were considered to be excellent both after 6 months and 1 year. Radiographic examinations and direct examinations (performed after extraction of teeth) did not reveal the same percentages of secondary caries in the proximal portion of restorations. Fracture of the marginal crest reached 3% during the first 6 months, but fracture was absent during the subsequent 6 months.

Bisphenol A-Glycidyl Methacrylate↗

PubMed1994

Reattachment of a tooth fragment with a "new" adhesive system: a case report.

A maxillary central incisor fractured, invading the biologic width. The biologic width was surgically restored, and in the same session the fragment was reattached to the tooth remnant with a "new" dentinal adhesive system. Short-term results indicate that esthetics, function, and oral health have been maintained.

Adult↗

PubMed1994

Adhesive restorations with amalgam: guidelines for the clinician.

The adhesive amalgam restoration technique combines the good properties of amalgam with the principles of tooth structure preservation and marginal seal inherent to adhesive materials. In spite of lack of longitudinal data, results of early clinical and laboratory tests are encouraging. If the present research is substantiated by clinical confirmation of their results, bonded amalgam restorations will become routine. The purpose of this article is to present a brief literature review on adhesive amalgam restoration and to introduce guidelines for its use.

Dental Amalgam↗

PubMed1993

Coronal fracture with invasion of the biologic width: a case report.

To repair a coronal fracture with invasion of the biologic width, flap surgery with osteotomy and osteoplasty localized on the fractured tooth was performed, and the crown was reattached to the tooth remnant with a composite resin system. Results after 6 years revealed optimal periodontal health and reasonable esthetics.

Adult↗