Five-year Clinical Evaluation of Universal Adhesives in Noncarious Cervical Lesions.

OBJECTIVES: To compare the clinical performance of mildly acidic universal adhesives Scotchbond Universal (SU, 3M Oral Care, St Paul, MN, USA) and Prime & Bond Elect (PBE, Dentsply Sirona, Charlotte, NC, USA) in the restoration of noncarious cervical lesions (NCCLs). METHODS AND MATERIALS: A total of 63 patients in need of 203 NCCL restorations participated in this randomized controlled clinical trial. Notch-shaped lesions were restored with Kalore (GC Corporation, Tokyo, Japan) after application of either SU or PBE, following the etch-and-rinse (ER) or self-etch (SE) techniques. Subjects were followed up for 60 months. The focus of the statistical analyses was on the change of outcome over time as assessed by the Modified USPHS rating system (ie, Alfa vs Bravo + Charlie outcomes). Logistic regression was performed for each outcome separately with compound symmetric variance-covariance structure assumed to consider a correlation of restorations within subjects. All analyses were conducted using SAS 9.4 (SAS, Cary, NC, USA). RESULTS: One-hundred twenty-nine teeth in 35 subjects were assessed at the 60-month follow-up. In addition, three restorations that failed prior to the 60-month evaluation, two of which were in subjects who did not present for the 60-month follow-up, were included in the statistical analysis. In total, two restorations in the SU_ER group and three restorations in the PBE_SE group failed the retention category. Statistically significant differences were obtained for the comparison of restorations in the PBE_SE and PBE_ER groups, where the former was 58% less likely to maintain a score of Alfa for marginal discoloration than the latter. CONCLUSIONS: SU and PBE demonstrated acceptable clinical performance at 60 months with regard to restoration retention. Phosphoric-acid etching of the NCCLs prior to adhesive application significantly improved the performance of PBE in regard to marginal discoloration.

Color Repair of a Composite Resin Restoration.

Fractured teeth with both enamel and dentin involvement might be treated with adhesive composite resin restorations. In cases where a perfect color match between the composite restoration and the remaining tooth structure is not achieved, a repair might be carried out to correct the color of restoration. This procedure avoids the restoration replacement, preserving tooth structure without compromising the esthetic outcome.

Effect of Surface Sealants and Polishing Time on Composite Surface Roughness and Microhardness.

The objective of this study was to evaluate the effect of surface sealants and polishing delay time on a nanohybrid resin composite roughness and microhardness. Eighty disc specimens were made with a nanohybrid resin (Esthet-X HD, Dentsply). The specimens were divided into two groups (n=40) according to polishing time: immediate, after 10 minutes; delayed, after 48 hours. Each group was subdivided into four groups (n=10), according to the surface treatment: CG, control-rubber points (Jiffy Polishers, Ultradent); PP, rubber points + surface sealant (PermaSeal, Ultradent); PF, rubber points + surface sealant (Fortify, Bisco); PB, rubber points + surface sealant (BisCover, Bisco). Surface roughness (Ra) and microhardness (50 g/15 seconds) were measured. Surface morphology was analyzed by scanning electron microscopy and atomic force microscopy. The data were analyzed statistically using one-way analysis of variance and the Games-Howell post hoc test (α=0.05). PermaSeal roughness (G2) in the delayed polishing group was significantly higher ( p=0.00) than that of the other groups. No difference was observed among the groups between immediate and delayed polishing ( p=1.00), except for PermaSeal ( p=0.00). Moreover, PermaSeal showed the lowest microhardness values ( p=0.00) for immediate polishing. Microhardness was higher at delayed polishing for all the surface treatments ( p=0.00) except Fortify ( p=0.73). Surface smoothness similar to polishing with rubber points was achieved when surface sealants were used, except for PermaSeal surface sealant, which resulted in a less smooth resin composite surface. However, surface sealant application did not significantly improve composite resin microhardness.

Eighteen-month Clinical Study of Universal Adhesives in Noncarious Cervical Lesions.

OBJECTIVE: To evaluate the clinical performance of Scotchbond Universal (3M Oral Care) and Prime & Bond Elect (Dentsply Sirona) in the restoration of noncarious cervical lesions (NCCLs). METHODS AND MATERIALS: This was a randomized controlled clinical trial involving 63 subjects. Two hundred and three NCCLs were restored using Scotchbond Universal and Prime & Bond Elect using both an etch-and-rinse and a self-etch technique. Lesions were notch-shaped NCCLs, and the restorations were placed without any mechanical retention. Restorations were finished immediately after placement and scored with regard to retention, marginal discoloration, marginal adaptation, and secondary caries. Similar assessment of the restorations was performed 18 months after placement. Logistic regression was performed for each outcome separately with a compound symmetric variance-covariance structure assumed to consider a correlation of restorations within subjects. All analyses were conducted using SAS version 9.4 (SAS Inc). RESULTS: One hundred and fifty-eight teeth (77.8% of the restorations placed) in 46 subjects (73% of subjects enrolled) were available for the 18-month follow-up. A statistically significant difference was reached only for the comparison Scotchbond Universal/self-etch (SU_SE) and Prime & Bond Elect/etch-and-rinse (PBE_E&R) groups ( p=0.01), where a restoration with SU_SE was 66% less likely to maintain a score of Alpha for marginal discoloration than a restoration performed with PBE_E&R. CONCLUSIONS: Scotchbond Universal and Prime & Bond Elect presented acceptable clinical performance after 18 months of clinical service. However, Scotchbond Universal, when applied with a self-etch approach, did demonstrate a relatively high level of marginal discoloration when compared to the other groups.

A Conservative Technique for Repairing Class IV Composite Restorations.

Composite resin may make a restoration noticeable as time passes, on account of its color instability. The repair technique is a minimally invasive treatment for class IV composite resin restorations that show unsatisfactory coloration. Thus, the objective of the present article was to report a clinical case involving a conservative technique used for repairing a class IV composite resin restoration in the left maxillary central incisor and the replacement of a class IV restoration in the right maxillary central incisor.

Microtensile Bond Strength of Composite Cement to Novel CAD/CAM Materials as a Function of Surface Treatment and Aging.

OBJECTIVES: To evaluate the effect of different surface treatments on the bond strength to a composite and a polymer-infiltrated ceramic CAD/CAM block after six-month artificial aging. METHODS AND MATERIALS: Two types of CAD/CAM blocks (Cerasmart, GC; Enamic, Vita Zahnfabrik) were cut in slabs of 4-mm thickness, divided into six groups, and subjected to the following surface treatments: group 1: no treatment; group 2: sandblasting (SB); group 3: SB + silane (Si); group 4: SB + Si + flowable composite (see below); group 5: 5% hydrofluoric acid etching (HF) + Si; and group 6: 37% phosphoric acid etching (H3PO4) + Si. Sections of the same group were luted together (n=3: 3 sandwich specimens/group) using a dual-cure self-adhesive cement for all groups, except for the sections of group 4 that were luted using a light-curing flowable composite. After three weeks of storage in 0.5% chloramine at 37°C, the sandwich specimens were sectioned in rectangular microspecimens and trimmed at the interface to a dumbbell shape (1.1-mm diameter). One half of the specimens was subjected to a microtensile bond strength (µTBS) test, and the other half was tested after six months of water storage (aging). Data were statistically analyzed with a linear mixed-effects model for the factors surface treatment, material type, and aging, together with their first-degree interactions (α=0.05). RESULTS: The lowest bond strengths were obtained in the absence of any surface treatment (group 1), while the highest µTBSs were obtained when the surface was roughened by either SB or HF, this in combination with chemical adhesion through Si. Loss in bond strength was observed after six-month aging when either surface roughening or silanization, or both, were omitted. CONCLUSIONS: Both the composite and polymer-infiltrated ceramic CAD/CAM blocks appeared equally bonding-receptive regardless of the surface treatment used. Creating a microretentive surface by either SB or HF, followed by chemical adhesion using Si, is mandatory to maintain the bond strength after six months.

Ceramic Veneers and Direct-Composite Cases of Amelogenesis Imperfecta Rehabilitation.

The aim of this article is to present two case reports for the treatment of patients affected with amelogenesis imperfecta. One case was treated with composite resin and the other case with ceramic veneers. Esthetic and functional results were achieved using both treatments, and a review of advantages and disadvantages is presented.

Tooth fragment reattachment: a case report.

The aim of this article is to present a case report for the multidisciplinary treatment of anterior tooth fractures with invasion of the biologic width and pulpectomy. Successful esthetic and functional results were achieved by bonding the crown fragment, without any form of preparation or the utilization of intracanal posts.

Cracked tooth syndrome in an unrestored maxillary premolar: a case report.

Cracked tooth syndrome is known to occur most frequently in heavily restored teeth. Nevertheless, when the symptoms occur in intact teeth, there is difficulty in obtaining a correct diagnosis because it is difficult for the dentist to find where the crack is located. This clinical report describes the diagnostic procedures and the direct bonded composite restoration used to restore an incompletely fractured unrestored maxillary premolar in a 22-year-old female patient. To achieve a correct diagnosis, the following were performed: periapical and bitewing radiographs, percussion and thermal vitality tests, a bite test, and the placement of a stainless steel band. Once the symptoms ceased with band placement, cone beam computed tomography, transillumination, macro photographs, and isolation with a rubber dam helped to visualize the crack line along the occlusal surface involving distal and mesial marginal ridges. The crack was traced using a high-speed tungsten carbide bur until the fracture line was not visible. The tooth was restored with a direct composite resin, associated with a total-etch adhesive system, and the symptoms were immediately eliminated.

Clinical effectiveness of a hydrophobic coating used in conjunction with a one-step self-etch adhesive: an 18-month evaluation.

The purpose of this randomized clinical trial was to evaluate the clinical performance of a one-step self-etch adhesive in noncarious cervical lesions with inclusion of a hydrophobic bonding layer not included in the original bonding system as a test of potentially improved bonding. Patients with noncarious cervical lesions received two or four restorations after being randomly assigned to two adhesive technique protocols (n=32): EB, application of Adper Easy Bond (3M ESPE) following manufacturer's instructions; and EB+B, application of Adper Easy Bond, immediately followed by the application of a hydrophobic resin coat (Scotchbond Multi-Purpose Bonding Agent, 3M ESPE). All restorations were restored with a microhybrid composite (Filtek Z250, 3M ESPE). Clinical effectiveness was recorded in terms of retention, marginal discoloration, marginal integrity, postoperative sensitivity, recurrent caries, periodontal health, and pulpal vitality, according to the modified USPHS criteria, for 18 months. Data were analyzed using chi-square, Fisher exact, and McNemar tests at α=0.05. Two restorations of each group were debonded after six months, leading to an overall clinical success rate of 93.8% for both groups. At the 18-month evaluation period, no new restoration was debonded. However, one restoration of the EB group displayed recurrent caries at the dentin margin, decreasing the overall success rate to 90.6% in comparison to 93.8% of EB+B. The success rate between EB and EB+B was not statistically significant (p=0.5). The application of a hydrophobic resin coat over EB did not increase bonding effectiveness in noncarious cervical lesions after 18 months.

A photoelastic assessment of residual stresses in zirconia-veneer crowns.

Residual stresses within the veneer are linked to the high prevalence of veneer chipping observed in clinical trials of zirconia prostheses. We hypothesized that the thermal mismatch between the zirconia infrastructure and the veneer porcelain, as well as the rate used for cooling zirconia-veneer crowns, would be directly proportional to the magnitude of residual stresses built within the veneer layer. Two porcelains with different coefficients of thermal expansion were used to veneer zirconia copings, to create high or low thermal mismatches. The crowns were cooled according to a fast- or a slow-cooling protocol. The retardation of polarized light waves was used to calculate the residual stress magnitude and distribution across the veneer, according to the photoelasticity principle, in 1.0-mm-thick crown sections. While thermal mismatch was an important factor influencing the maximum stress development in the veneer, cooling rate had a minor role. Curved surfaces were preferential sites for stress concentration regardless of thermal mismatch or cooling rate.

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.

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.

Does clinical experience affect occlusal caries diagnosis and sealant recommendation? An in vitro study.

The purpose of this in vitro study was to evaluate the effect of the length of clinical experience on clinician's diagnosing caries and recommending sealants on the occlusal surfaces of permanent/caries free third molars. The third molars involved in this study had been extracted prior to eruption. There were three study groups: dental students, clinicians with five to ten years experience, and clinicians with fifteen to twenty years of practice. Twenty-four percent of the entire sample diagnosed caries. Clinicians with five to ten years of practice diagnosed occlusal caries significantly more than clinicians with fifteen to twenty years of practice, but not significantly differently than senior dental students. Clinicians recommended sealants significantly more than dental students. The most frequent reason for sealant indication was prevention. The results indicate that clinical experience alone does not impart better caries diagnosis and sealant recommendation criteria.

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.

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.

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.

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.

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.