Adhesive dentistry: Current concepts and clinical considerations.

OBJECTIVES: To address contemporary concepts in adhesive dental materials with emphasis on the evidence behind their clinical use. OVERVIEW: Adhesive dentistry has undergone major transformations within the last 20 years. New dental adhesives and composite resins have been launched with special focus on their user-friendliness by reducing the number of components and/or clinical steps. The latest examples are universal adhesives and universal composite resins. While clinicians prefer multipurpose materials with shorter application times, the simplification of clinical procedures does not always result in the best clinical outcomes. This review summarizes the current evidence on adhesive restorative materials with focus on universal adhesives and universal composite resins. CONCLUSIONS: (a) Although the clinical behavior of universal adhesives has exceeded expectations, dentists still need to etch enamel to achieve durable restorations; (b) there is no clinical evidence to back some of the popular adjunct techniques used with dental adhesives, including glutaraldehyde-based desensitizers and matrix metalloproteinase inhibitors; and (c) the color adaptation potential of new universal composite resins has simplified their clinical application by combining multiple shades without using different translucencies of the same shade. CLINICAL SIGNIFICANCE: New adhesive restorative materials are easier to use than their predecessors, while providing excellent clinical outcomes without compromising the esthetic quality of the restorations.

Surgical Treatment of Polyostotic Craniomaxillofacial Fibrous Dysplasia Associated With Acromegalia: The McCune - Albright Syndrome.

INTRODUCTION: The McCune-Albright syndrome (MAS) is a complex congenital disorder caused by the embryonic post-zygotic somatic activating mutations in the GNAS1 gene. In such syndrome, phenotypes are heterogeneous and comprised polyostotic/monostotic fibrous dysplasia, café au lait macules, and hyperfunctioning endocrinopathies as the excess growth hormone. Likewise, acromegaly, as a manifestation of the endocrine hyperfunction, is unusual and affects about 20% of patients with MAS. CASE PRESENTATION: This research study describes a case of a 31-year-old female subject presenting polyostotic fibrous dysplasia with severe facial involvement, along with acromegaly and the MAS. The case was satisfactorily managed by surgical re-alignment and presented no clinical signs of relapse in a 12-year follow-up period. Finally, a literature review was conducted to discuss the standard protocols and the controversies when treating such cases. CONCLUSION: Patients with craniomaxillofacial fibrous dysplasia associated with acromegaly may present significant facial deformities that can be satisfactorily treated by cosmetic treatment, especially in patients with psychological problems and severe social acceptance.

Prefabricated composite resin veneers--a clinical review.

OBJECTIVE: This clinical technique article is focused on the use of prefabricated veneers to enhance the esthetic appearance of the anterior dentition in patients who needed an alternative esthetic solution more affordable than traditional porcelain veneers. CLINICAL CONSIDERATIONS: Because prefabricated composite veneer systems have been recently introduced, they are not widely used. The Componeer system (Coltene, Altstätten, Switzerland) contains thin pre-polymerized hybrid composite shells, several shades of a direct hybrid composite resin, an etch-and-rinse adhesive system, and restorative accessories including finishing points and disks. The prefabricated restorations can be customized in the mouth for color and shape. The technique described in this article can be used to restore function and esthetics in one office visit. CONCLUSIONS: The prefabricated composite veneer technique has some of the advantages of direct composite restorations, as only one session is required without the need to take impressions to send to the dental laboratory. This new treatment option may open new opportunities for dental professionals and their patients. However, it is paramount to carry out controlled clinical studies with this restorative technique prior to recommending it without restrictions in general practice. CLINICAL SIGNIFICANCE: The clinical technique described in this paper has the potential for being used routinely to lengthen anterior teeth, to correct malpositioned teeth, to mask discolorations, and to close diastemas. The technique can also be used to restore extensive caries lesions and tooth fractures, and to refurbish large old anterior restorations, especially when other treatment options are out of reach for the patient for financial reasons.

Microtensile bond strengths and interfacial examination of a polyalkenoate-based 1-step adhesive.

PURPOSE: To study the effect of acid etching and the application of a hydrophobic bonding resin on the microtensile bond strengths (microTBS) and marginal sealing of the 1-step self-etch adhesive Adper Easy Bond (AEB). METHODS: Middle dentin was exposed in 30 extracted molars and randomly divided into six groups: (1) AEB applied as per manufacturer's directions; (2) as in AEB, but one coat of hydrophobic resin (HR) was applied and cured over AEB (AEB+HR); (3) etching with 35% H3PO4 for 15 seconds followed by AEB (Etch+AEB); (4) as in group Etch+AEB, but one coat of HR was applied and cured over AEB (Etch+AEB+HR); (5) Adper Single Bond Plus, the 2-step etch-&-rinse adhesive control (ASB); (6) Adper Scotchbond Multi-Purpose, the 3-step etch-&-rinse adhesive control (SBMP). Buildups were constructed with Filtek Z250 and cured in three increments of 2 mm each. Specimens were sectioned with a slow-speed diamond saw under water in X and Y directions to obtain bonded sticks with a cross section of 0.8 +/- 0.2 mm2 and tested to failure in tension mode at a crosshead speed of 1 mm/minute. Statistical analyses were computed using one-way ANOVA followed by Duncan's post-hoc test at P<0.05. For marginal sealing, 36 Class V preparations were restored with one of the six adhesive combinations and processed with 50% ammoniacal silver nitrate. After sectioning, specimens were observed under a backscattered FE-SEM to evaluate silver infiltration into the resin-dentin interface, which was measured in ranks (0-4) and compared with non-parametric statistical tests (P<0.05). RESULTS: AEB resulted in statistically lower mean microTBS than all other groups at P0.05. All the remaining groups resulted in statistically similar mean microTBS. For marginal sealing, data were grouped in three statistical subsets: Groups AEB and AEB+HR resulted in statistically less silver infiltration than groups Etch+AEB and Etch+AEB+HR. Groups ASB and SBMP resulted in similar silver infiltration compared to Groups AEB and AEB+HR. The nanoleakage pattern consisted of agglomerates of silver deposits located predominantly in the hybrid layer, while reticular or water-tree silver deposits were observed in both the AEB and ASB adhesive layers.

Bonding ability of three ethanol-based adhesives after thermal fatigue.

PURPOSE: To study the effect of thermal fatigue on the microTBS and interfacial morphology of three ethanol-based etch-&-rinse 2-bottle adhesives. METHODS: microTBS - 24 third molars were randomly assigned to one of three adhesive systems: (1) Adper Single Bond Plus (SBP, 3M ESPE); (2) Ambar (AMB, FGM); (3) Excite (EXC, Ivoclar Vivadent), and restored with a hybrid resin composite. For each adhesive, half of the specimens were thermocycled (TC) for 20,000 cycles (5-55 degrees C) while the other half was kept in distilled water for 24 hours at 37 degreesC (control). Specimens were sectioned in X and Y directions and the resulting sticks were tested to failure in tension mode at a crosshead speed of 1 mm/minute. Statistical analysis was computed using ANOVA and Tukey's post hoc for the microTBS; and non-parametric cross-tabulation with Chi-Square for the pre-testing failures at P< 0.05. Interfacial morphology -The occlusal enamel was removed from 12 extracted molars perpendicular to the long axis of the tooth. Teeth were equally assigned to one of the three adhesives and restored with a 1 mm-thick layer of a hybrid composite resin. A 2 mm-thick disk was sectioned from each specimen and cross-sectioned in two identical halves. Half of the each specimen was TC for 20,000 cycles (5-55 degrees C) while the other half was kept in distilled water for 24 hours at 37 degrees C (control). Specimens were chemically challenged and prepared for FESEM observation to observe the integrity of the hybrid layer before and after thermal fatigue. Micrographs were recorded digitally at standard magnifications and measurements were taken with the microscope embedded image software. RESULTS: microTBS - SBP and AMB resulted in statistically similar mean microTBS regardless of thermal fatigue. EXC resulted in statistically lower mean microTBS than SBP and AMB for the control (P< 0.001) and for the TC specimens (P< 0.0001). Interfacial morphology - The hybrid layers of SBP and AMB were densely infiltrated without interfacial failure. For EXC, extensive areas of debonding were observed between the adhesive layer and the hybrid layer both for the control and the TC groups. Thermal fatigue did not influence the bonding ability of AMB and SBP, but was detrimental for EXC.

In vitro sealing potential of a self-adhesive pit and fissure sealant.

OBJECTIVE: To study the sealing ability of a self-adhesive sealant. METHOD AND MATERIALS: Thirty-five extracted molars were assigned to seven groups: group 1, 35% phosphoric acid (PA) followed by Clinpro Sealant (CL) as the control group; group 2, Enamel Loc (EL), a self-adhesive sealant; group 3, PA followed by EL; group 4, Adper Prompt L-Pop (AP) followed by CL; group 5, AP followed by EL; group 6, PA followed by Adper Single Bond Plus (SB) and CL; and group 7, PA followed by SB and EL. Specimens were thermocycled and immersed in 50 wt% ammoniac silver nitrate. Silver leakage was measured in ranks from 0 to 4 and analyzed with Kruskal-Wallis and Mann-Whitney tests at P < .05. One additional tooth per group was used to study the enamel etching pattern. Specimens were observed under a field-emission SEM. RESULTS: The least silver infiltration was measured for group 1 (control group), which was significantly different from all other six groups. Etching enamel prior to the application of EL resulted in significantly less leakage than all other groups, except for the control group. EL alone resulted in similar leakage to EL with either AP or SB. None of the groups resulted in perfectly sealed interfaces. Under SEM, EL was unable to etch enamel. The self-etch adhesive AP resulted in a less defined etching pattern than the etch-and-rinse adhesive SB. CONCLUSION: Etching enamel with phosphoric acid is still essential for sealing the enamel-sealant interface. The self-adhesive sealant tested in this study may not be indicated for clinical use.

Sealing ability of three fiber dowel systems.

PURPOSE: To study the sealing ability of two new fiber dowel systems. MATERIALS AND METHODS: Thirty-six extracted single-rooted teeth were endodontically treated and randomly assigned to two new fiber dowel systems and a control group: (1) an E-glass-based dowel, everStick-POST, cemented with ParaCem Universal DC resin cement (EV); (2) a glass-fiber dowel, RelyX Fiber Post, cemented with RelyX Unicem self-adhesive resin cement (RX). The control group was restored with a glass-fiber dowel, ParaPost Fiber Lux, cemented with ParaCem Universal DC resin cement (PP). The roots were isolated and immersed in a 50 wt% ammoniacal silver nitrate solution for 24 hours followed by 8 hours in a photo-developing solution. The roots were sectioned in 1-mm-thick disks perpendicular to the long axis of the root. The specimens were processed for backscattered FESEM observation. For each tooth, the depth of silver infiltration into the root canal was measured by ranks from 0 to 8. For each disk, silver infiltration was measured as the percentage of leakage around the adhesive interface. Data were analyzed with Kruskal-Wallis nonparametric tests at a significance level of 95%. RESULTS: When the silver infiltration was computed from the coronal to the apical aspects of the root, RX resulted in the lowest degree of silver infiltration, but not statistically different from that of EV (p < 0.148). RX, however, resulted in a lower depth of silver infiltration than the control group PP at p < 0.023. EV resulted in a statistically similar depth of penetration to PP (p= 0.492). Although the total mean percentage of silver infiltration at the dentin-resin cement interface was statistically similar for all groups (p= 0.632), EV resulted in the greater number of disks with silver infiltration (23 out of 96), followed by PP (21 out of 96) and RX (14 out of 96). None of the specimens showed leakage around the dowel-resin cement interface. CONCLUSION: The use of the E-glass dowels in EV did not improve the root-wall sealing ability compared with the control group PP. The system RX, which uses a new simplified self-adhesive protocol, resulted in a lower depth of silver infiltration than the control group PP.

In vitro enamel sealing of self-etch adhesives.

OBJECTIVE: The use of self-etch adhesives has increased in spite of reports of deficient enamel bonding. Some clinicians etch enamel separately to circumvent this shortfall. Therefore, the objective of this study was to assess the influence of acid-etching on the enamel sealing of 3 self-etch adhesives after thermal fatigue. METHOD AND MATERIALS: Two box-type preparations were restored in each of 30 bovine incisors with 1 of 3 self-etch adhesives: Adper Prompt L-Pop (3M ESPE); Clearfil SE Bond (Kuraray America); or iBond (Heraeus Kulzer), with and without phosphoric acid enamel etching, followed by Filtek Z250 (3M ESPE). After half of the restorations were fatigued for 1,500 thermal cycles, marginal sealing was challenged with 50% ammoniacal silver nitrate. Silver penetration was ranked from 0 to 4 and interfaces analyzed under a field-emission scanning electron microscope (FESEM) with a backscattered detector. Nonparametric statistical analyses were carried out at a 95% confidence level. RESULTS: Clearfil SE Bond resulted in significantly less enamel leakage than the other 2 self-etch adhesives. Acid etching significantly reduced silver infiltration for all adhesives when specimens were thermocycled. When specimens were not thermocycled, acid etching only reduced silver infiltration for iBond. Under the FESEM, silver deposition was observed inside the adhesive layer for Adper Prompt L-Pop and iBond. For Clearfil SE Bond only 2 of 10 specimens displayed silver infiltration along the enamel-adhesive interface. CONCLUSION: Etching with phosphoric acid improved the enamel marginal sealing of the 3 self-etch adhesives when specimens were subjected to thermal fatigue.

Restoring teeth with prefabricated fiber-reinforced resin posts.

The use of fiber-reinforced resin (FRR) posts to restore endodontically treated teeth has gained popularity as an alternative to cast or pre-fabricated metal posts. This may be due to the two important characteristics of fiber posts: (1) their modulus of elasticity, which is similar to that of dentin, and (2) their ability to be adhesively cemented. The following article will discuss these characteristics, clinical indications for FRR posts, as well as increased fracture resistance, adhesion to root dentin, and guidelines for placement.

In vitro bonding performance of self-etch adhesives: II--ultramorphological evaluation.

OBJECTIVE: To study the interfacial ultra-morphology formed by "all-in-one" self-etch adhesives. METHODS: Forty-nine extracted molars were assigned to one of five all-in-one adhesives: Adper Prompt L-Pop (AP, 3M ESPE); Clearfil S3 Bond (S3, Kuraray); G-Bond (GB, GC America); iBond (iB, Heraeus Kulzer) and Xeno IV (XE, Dentsply Caulk). Adper Single Bond Plus (SB, 3M ESPE), a two-step etch&rinse adhesive, and Clearfil SE Bond (SE, Kuraray), a two-step self-etch adhesive, were used as controls. Dentin, unground enamel and ground enamel were used as bonding substrates. Dentin specimens were processed for FESEM and TEM analyses. Enamel specimens were processed for FESEM. RESULTS: Dentin: GB, iB, S3, SE and XE resulted in a submicron-thick hybrid layer (0.2-0.7 microm), but only S3 and SE did not result in interfacial gaps. AP resulted in the thickest hybrid layer (1.7-2.9 microm) among the self-etch adhesives. SB resulted in a 3.4-5.2 pm thick hybrid layer. Unground enamel-GB, iB and SE resulted in a mostly featureless morphology resembling that of untreated enamel with areas in which the superficial enamel layer was removed without dissolving the subsurface enamel. XE resulted in areas of intra-prismatic etching and areas without any etching pattern. S3 resulted in frequent shallow intra-prismatic etching, while AP was able to unveil the enamel crystallites across the entire enamel surface. Phosphoric acid in SB resulted in the deepest intra- and inter-prismatic demineralization. Ground enamel--AP resulted in a well-defined inter-prismatic etching pattern. iB, GB, SE and S3 resulted in islands of superficially dissolved enamel within areas without evidence of enamel dissolution. XE resulted in etched enamel areas with mild intraprismatic exposure of crystallites. Phosphoric acid in SB resulted in deep enamel etching. CONCLUSIONS: Only AP, an aggressive self-etch adhesive, showed enamel morphological features that resemble those created by etch & rinse adhesives. S3 and SE were the only self-etch adhesives that did not result in dentin interfacial debonding.

Restoring teeth with prefabricated fiber-reinforced resin posts.

UNLABELLED: The use of fiber-reinforced resin (FRR) posts to restore endodontically treated teeth has gained popularity as an alternative to cast or prefabricated metal posts. This may be due to the two important characteristics of fiber posts: I) their modulus of elasticity, which is similar to that of dentin, and 2) their ability to be adhesively cemented. The following article will discuss these characteristics, clinical indications for FRR posts, as well as increased fracture resistance, adhesion to root dentin, and guidelines for placement. LEARNING OBJECTIVES: This article reviews recent research on prefabricated fiber-reinforced resin (FRR) endodontic posts. Upon completing this article, the reader should: Understand clinical guidelines for the selection and cementation of FRR posts. Realize the importance of fracture resistance to the long-term performance of an endodontically treated tooth.

The effect of dowel space on the bond strengths of fiber posts.

PURPOSE: The purpose of this study was to evaluate the effect of the degree of mismatch between post space and post diameters on the bond strength of a fiber-reinforced resin post. MATERIALS AND METHODS: Thirty-two extracted human maxillary central incisors and canines were endodontically treated and assigned to four groups: Group 1--Canal prepared with a D.T. Light Post #1 drill (control); Group 2--Canal prepared with a D.T. Light Post #2 drill; Group 3--Canal prepared with a D.T. Light Post #3 drill; Group 4--Canal prepared with a Gates Glidden #6 drill. A D.T. Light Post size 1 was then luted into the canal using One-Step Adhesive and Post Cement Hi-X. A push-out test was performed on three sections of each root to measure push-out bond strengths. Data were analyzed with ANOVA and Bonferroni's test at p < 0.05. Two extra teeth for each group were restored in the same fashion and processed for SEM observation. RESULTS: (in MPa): Group 1: 15.7 +/- 6.9; Group 2: 14.7 +/- 6.5; Group 3: 14.0 +/- 5.0; Group 4: 14.0 +/- 5.1. The variable "post space" resulted in no statistically significant difference in mean bond strengths (p > 0.05). For the variable "root region," the coronal third (17.5 +/- 6.0) resulted in statistically greater mean bond strengths than the apical third (12.3 +/- 6.0) at p < 0.008. The middle third (14.0 +/- 5.3) resulted in no statistically significant different mean bond strengths from the coronal third at p > 0.119 and from the apical third at p > 0.999. Under the SEM, some areas of the canal system still displayed residual gutta-percha, which resulted in debonding of the interface between the resin cement and dentin. Areas with incomplete dentin hybridization were observed in localized areas of all groups. CONCLUSIONS: The diameter of the post space did not affect the push-out bond strengths. Bonding at the coronal level of the root canal is more reliable than bonding at the apical level. The presence of residual gutta-percha and the deficient dentin hybridization may result in deficient seal of the resin-dentin interface.

Interfacial adaptation of adhesive materials to root canal dentin.

Extracted single-rooted maxillary teeth were endodontically treated and filled with gutta-percha/AH-26 (GP), Resilon points/RealSeal (RS), AdheSE DC/Multicore Flow (ADH, self-etch control), or Excite DSC/Multicore Flow (EXC, total-etch control). Specimens were analyzed with electron microscopy using three methods: (a) field emission scanning electron microscopy (FESEM) of the interface; (b) transmission electron microscopy (TEM) of the interface; and (c) FESEM of the material fitting surface. The three adhesive materials (RS, ADH, and EXC) formed a dentin hybrid layer, which nonetheless resulted in interfacial separation. Gaps were more frequent for GP, which did not hybridize dentin. The fitting surfaces exhibited resin tags at all levels for EXC. Tags were less frequent with ADH, especially in the apical third. For RS, resin tags were rare and virtually absent from the apical half, whereas GP did not form tags. Despite the hybridization, a tight seal of the root canal is difficult to achieve because of the complexity and the mechanical challenge of the substrate.

Effect of instrument lubricant on the cohesive strength of a hybrid resin composite.

OBJECTIVES: The purpose of this study was to evaluate the effect of instrument lubricant on the cohesive strength of resin composite layers. METHOD AND MATERIALS: Clear acrylic molds were filled with 3 increments of a hybrid resin composite using a metal instrument. The first increment (shade A2) was inserted to a height of 4 mm and light cured, followed by a 1-mm-high second increment (shade A1). The composite instrument was then wiped with 1 of 7 lubricants before insertion of a 1-mm-high third increment (shade A1): (1) isopropyl alcohol gauze, 70% v/v (AL); (2) acetone (AC); (3) Adper Single Bond Adhesive (SB); (4) One-Step Adhesive (OS); (5) D/E Bonding Resin (DE); (6) Scotchbond Multi-Purpose Adhesive (SP); (7) Tescera Sculpting Resin (TE). No lubricant was used in the control group (CT). A final 4-mm-high increment (shade A2) was inserted and light cured. The blocks were sectioned to obtain 48 sticks for each group. Sticks were fractured with an Instron machine. Statistics were computed using 1-way analysis of variance and Duncan's test. RESULTS: Outcomes were as follows (mean +/- SD, MPa; same letters indicate significant differences at a confidence level of 95%): TE = 96.7A +/- 17.8; SP = 93.6AB +/- 9.6; DE = 93.4AB +/- 16.2; OS = 91.9AB +/- 19.5; AC = 90.1ABC +/- 12.2; SB = 89.9ABC +/- 14.5; AL = 88.8BC +/- 16.8; CT = 84.7C +/- 8.3. CONCLUSIONS: Although the difference between Tescera Sculpting Resin and alcohol was statistically significant, Tescera Sculpting Resin is recommended only for indirect composite restorations. The lubricant used to reduce stickiness between the resin composite used for direct restorations and the composite instrument did not significantly reduce bond strengths.

The effect of silane on the bond strengths of fiber posts.

OBJECTIVES: Esthetic posts have been developed to maximize the foundation of esthetic restorations. The purpose of this study was to evaluate the effect of silane on the bond strength of three fiber-reinforced resin posts (fiber posts). METHODS: Fifty-four extracted human maxillary central incisors and canines were endodontically treated. D.T. Light Post (DT, Bisco), FRC Postec (FR, Ivoclar Vivadent), and ParaPost Fiber White (PP, Coltène/Whaledent) were inserted using the resin adhesive system provided by the respective manufacturer. For half of the specimens in each group, the fiber posts were treated with a silane solution (Monobond S, Ivoclar Vivadent). A push-out test was performed on three different sections of each root to measure bond strengths. Data were analyzed with ANOVA and Bonferroni's post hoc test at P<0.05. RESULTS: The use of silane did not result in any statistically significant difference at any level of the root. Silane did not result in any significant different bond strengths (MPa) for each of the posts. When the data were pooled, the use of silane did not result in statistically significant different bond strengths at P>0.403: No silane=12.7+/-8.4; Silane=14.1+/-7.0. The coronal third of the root (17.5+/-6.7) resulted in statistically greater bond strengths than the medium third (12.9+/-6.8) and than the apical third (9.8+/-7.3) at P<0.002 and P<0.0001, respectively. The medium third and the apical third resulted in no statistically significant different bond strengths from each other at P>0.07. The type of post did not result in statistically significant different bond strengths at P>0.417: DT=14.7+/-6.8 MPa; FR=13.3+/-6.6 MPa; PP=12.2+/-6.6 MPa. SIGNIFICANCE: The use of a silane coupling agent did not increase the push-out bond strengths of the three fiber posts used in this study. All posts bonded to root dentin at the same magnitude. Bonding is more predictable at the most coronal level of the root.

Influence of conditioning time on enamel adhesion.

OBJECTIVE: The aim of this study was to calculate enamel bond strengths of 4 self-etch adhesives in function of conditioning time. METHODS AND MATERIALS: Sixty proximal surfaces of 30 extracted human molars were roughened and assigned to 4 self-etch adhesives: AdheSE (Ivoclar Vivadent), Adper Prompt L-Pop (3M Espe), Clearfil SE Bond (Kuraray America), and Tyrian SPE/One-Step Plus (Bisco). Prime & Bond NT (Dentsply) was used as the total-etch control. For 30 surfaces, the adhesives were applied per the manufacturers' directions. For the remaining 30, enamel was conditioned for twice the time recommended by the manufacturer. Buildups were constructed with Filtek Z250 (3M ESPE). Bonded specimens were sectioned in sticks and tested to tensile failure. Data were analyzed with 2-way ANOVA and Duncan's test at P < .05. The pH of the self-etch solutions and the phosphoric acid gel was measured with a pH meter. A correlation coefficient was computed to measure the linear association between pH and bond strengths. RESULTS: Tyrian SPE and Prime & Bond NT, the adhesives whose acidic conditioners yielded the lowest pH, ranked in the highest subset regardless of application time. AdheSE and Clearfil SE Bond, which had the highest pH, were the only adhesives for which double application time resulted in statistically higher bond strengths than the recommended time. When means were pooled for application time, Tyrian SPE and Prime & Bond NT resulted in bond strengths that were significantly higher than those of the remaining adhesives. AdheSE resulted in statistically lower bond strengths than any other adhesive. A significant correlation was found between pH and mean bond strengths. CONCLUSION: Doubling the enamel conditioning time might increase bond strengths for specific self-etch adhesives.

In vitro bonding performance of all-in-one adhesives. Part I--microtensile bond strengths.

PURPOSE: The objective of this project was to compare the microtensile bond strengths (microTBS) of five "all-in-one" adhesives using two 2-step adhesives as controls. MATERIALS AND METHODS: Eighty-four extracted human molars were randomly assigned to one of three substrates: dentin, unground enamel, or ground enamel. For each substrate, specimens were randomly assigned to one of five all-in-one adhesives: (1) Adper Prompt L-Pop (AP, 3M ESPE); (2) Clearfil S3 Bond (S3, Kuraray); (3) G-Bond (GB, GC America) (4) iBond (iB, Heraeus Kulzer); (5) Xeno IV (XE, Dentsply Caulk). Adper Single Bond Plus (SB, 3M ESPE) was used as a two-step etch-and-rinse control, while Clearfil SE Bond (SE, Kuraray) was used as a two-step self-etching control. Crowns were built with Filtek Z250 (3M ESPE) and sectioned in x and y directions. The resulting sticks were fractured in tension at a crosshead speed of 1 mm/min. Statistical analysis was computed for each substrate with one-way ANOVA and Duncan's post-hoc test at p < 0.05. RESULTS: Means+/-SD are given in MPa; pretesting failures are shown in brackets. Dentin--SE: 79.1+/-20.5, [0/85]; SB: 76.3+/-19.3, [0/82]; AP: 51.6+/-21.9, [0/90]; XE: 40.5+/-22.9, [7/81]; S3: 27.8+/-13.2, [7/91]; iB: 17.4+/-15.6, [25/91]; GB: 11.7+/-7.4, [5/92]. Unground enamel--SB: 33.1+/-10.5, [0/69]; AP: 27.6+/-7.5, [0/66]; S3: 24.6 +/-12.0, [0/70]; SE: 16.8+/-11.7, [3/60]; XE 15.4+/-14.1, [16/63]; iB: 11.2+/-11.5, [18/64]; GB: 9.5+/-12.4, [31/63]. Ground enamel--SB: 33.7+/-9.1, [0/69]; AP: 33.2+/-7.9, [0/77]; SE: 26.4+/-9.5, [0/67]; S3: 25.5+/-8.9; [0/56]; XE: 21.0 +/-8.9, [3/68]; GB: 18.2+/-10.3, [4/68]; iB: 12.3+/-8.9, [11/52]. For dentin, the Duncan's test ranked the means in 6 statistical subsets: GB

Enamel bond strengths of pairs of adhesives from the same manufacturer.

Most manufacturers of dental adhesives have both a total-etch adhesive and a simplified self-etching adhesive available on the market. This study measured the enamel microtensile bond strengths of five pairs of enamel adhesives as a function of enamel roughness. The proximal surfaces of 25 extracted mandibular molars were sectioned with a diamond saw to obtain 50 enamel rectangles with an area of 8x4 mm2. The enamel rectangles were divided in two equal parts via a groove to obtain 4x4 mm2 squared bonding surfaces. One half was roughened with a coarse diamond bur under water for five seconds, while the other half was kept intact. The enamel surfaces were randomly assigned to 10 enamel adhesives grouped into five pairs. Each pair included one self-etch adhesive and one total-etch adhesive from the same manufacturer: Adper Prompt and Adper Single Bond (PLP and SB, 3M ESPE); AdheSE and Excite (ADH and EXC, Ivoclar Vivadent); OptiBond Solo Plus SE and OptiBond Solo Plus (OPTSE and OPT, Kerr); Tyrian SPE/One-Step Plus and One-Step (TYR and OST, BISCO, Inc); Xeno III and Prime&Bond NT (XEN and PBNT, Dentsply). The adhesives were applied according to the manufacturers' instructions. Buildups were constructed with Filtek Z250 (3M ESPE). The specimens were sectioned in sticks with a cross section of 0.8+/-0.2 mm2 and tested to failure in tension at a crosshead speed of 1 mm/minute. Two-way ANOVA followed by Duncan's post-hoc test at p<0.05 was computed. The highest mean bond strengths were obtained with total-etch adhesives. For "roughened enamel," three pairs of materials had statistically different means in which the total-etch adhesive resulted in statistically higher bond strengths (MPa) than the corresponding self-etch adhesive: EXC (36.6) > ADH (23.0) at p<0.026; OPT (34.5) > OPTSE (25.3) at p<0.028; PBNT (36.6) > XEN (19.5) at p<0.0001. For "intact enamel," four pairs of materials resulted in statistically different means: SB (31.7) > PLP (20.9) at p<0.049; EXC (37.9) > ADH (16.3) at p<0.0001; OST (30.1) > TYR (18.0); PBNT (43.8) > XEN (16.0) at p<0.0001. When the same adhesive was compared on intact vs roughened enamel, all the self-etch materials resulted in lower bond strengths on intact enamel, but this difference was only significant for TYR (p<0.042) and ADH (p<0.050). For total-etch materials, only OPT resulted in statistically lower bond strengths when applied on intact enamel p<0.011).