A three-year clinical evaluation of two-bottle versus one-bottle dentin adhesives

BACKGROUND: The authors conducted an in vivo investigation to compare the clinical performance of two commercial one-bottle adhesives and a two-bottle adhesive for restoration of noncarious cervical lesions (NCCLs). METHOD: The patient pool consisted of 57 patients and 171 teeth (three teeth per patient), with one NCCL per tooth. Each patient received three resin-based composite restorations, each with a different adhesive: one tooth with a two-bottle, water-based adhesive as the control; another tooth with a one-bottle, ethanol-based adhesive; and a third tooth with a one-bottle, solvent-free adhesive. The authors assessed restorations in terms of retention, marginal integrity, margin discoloration and air sensitivity at baseline, six months, one year, two years and three years after initial placement. RESULTS: The retention rates at 36 months were 88 percent for the first adhesive, 81 percent for the second adhesive and 90 percent for the third adhesive. No statistically significant differences in retention rates could be shown, with 86 percent of restorations retained overall. Measures of marginal integrity, marginal discoloration and sensitivity also had no statistically significant differences between the three adhesives (P > .05). CONCLUSIONS: All three adhesives performed with acceptable outcomes after a 36-month period, with small differences between the one- and two-bottle systems and between the various solvents. Retention rate was moderately high and air sensitivity was markedly reduced; however, superficial marginal discoloration and marginal degradation was notable. Certain lesion, tooth and patient characteristics may predispose restorations to retention failure. CLINICAL IMPLICATIONS: The type of solvent may not be a major factor in retention of Class V restorations in NCCLs. Both single-bottle adhesives and conventional two-bottle adhesives performed acceptably.     

One-year clinical evaluation of an ethanol-based and a solvent-free dentin adhesive

PURPOSE: To analyze the clinical performance of adhesives with various solvents for restoration of non-carious cervical lesions. METHODS: The patient pool consisted of a total of 57 patients and 171 teeth (3 teeth per patient), with one non-carious cervical lesion per tooth. For each patient, one tooth was restored with a water-based, two-bottle adhesive (Scotchbond Multi-Purpose - SM), and another tooth with an ethanol-based, one-bottle adhesive (Single Bond - SB), and the other tooth with a solvent-free, one-bottle adhesive (One Coat Bond - OCB), all with resin-based composites (Silux Plus or Synergy). Restorations were assessed by retention, marginal integrity, margin discoloration and air sensitivity, according to modified USPHS criteria. The evaluations were performed at baseline, 6 months and 12 months after initial placement. RESULTS: The retention rates at 12 months were 98% for the SM adhesive, 91% for the SB adhesive, and 93% for the OCB adhesive. The differences in retention rates were not statistically significant, with 94% restorations retained overall. Measures of marginal integrity, marginal discoloration and sensitivity also had no statistically significant differences between the three adhesives. Overall, for the restorations still retained after 12 months, 80% had non/slightly detectable margins, 80% had no marginal discoloration and 90% had none/mild sensitivity. All three adhesives performed comparably with excellent outcomes after a 12-month period, with no significant differences between the water-based, ethanol-based and solvent-free adhesives, nor between the one-and two-bottle systems. Retention rate was high, air sensitivity was markedly reduced, and marginal integrity was good. Although superficial marginal discoloration was notable, no deep staining was evident. Certain lesion, tooth and patient characteristics may predispose restorations to retention failure.     

Effect of dentine conditioners on the bonding efficacy of one-bottle adhesives

The bonding efficacy of four one-bottle adhesives (OptiBond Solo Plus, Gluma Comfort Bond, One Step and Prime & Bond NT) and a multi-step adhesive (Clearfil Photo Bond) as a control was evaluated. The dentine cavity wall was conditioned with phosphoric acid or ethylenediaminetetraacetic acid (EDTA) and the marginal integrity was estimated by measuring the wall-to-wall contraction gap width between the composite and the dentine cavity surface. In the positive control group, the adhesive was applied following glyceryl methacrylate (GM) priming. The analyses were performed by Kruskal-Wallis and Mann-Whitney U-tests. One-bottle adhesives were clearly inferior to the multi-step bonding system in marginal integrity when dentine was conditioned with EDTA. The present findings also suggested that the marginal sealing ability of ethanol-based one-bottle systems was better than acetone-based one-bottle systems when dentine surfaces were conditioned with EDTA. Nevertheless, further investigations are needed on the function of fillers in one-bottle adhesives for the prevention of contraction gaps.     

Eighteen-month clinical evaluation of a filled and unfilled dentin adhesive

OBJECTIVE: The purpose of this study was to evaluate the performance of a filled (OptiBond Solo) and an unfilled (Prime & Bond 2.1) "one-bottle" adhesive in Class V restorations after 18 months of clinical service. METHODS: Thirty-three patients with non-carious cervical lesions were enrolled in the study. A total of 101 lesions were restored using one of the adhesives and a hybrid composite resin. Enamel was not beveled, nor was any mechanical retention placed. The restorations were evaluated at baseline, and at 6 and 18 months after placement using modified USPHS criteria. RESULTS: Cumulative 18-month retention rates were 93.6% for OptiBond Solo and 98.0% for Prime & Bond 2.1. The difference in retention rates was not statistically significant. For OptiBond Solo, the only notable problems were interfacial staining and marginal adaptation, both of which were less than ideal in 9% of restorations. Marginal problems were slightly less frequent for Prime & Bond 2.1 restorations, but the difference was not significant. CONCLUSIONS: Both adhesives provided Class V retention rates exceeding the 18-month, full acceptance guidelines set by the American Dental Association. Any additional benefit provided by the use of a filled adhesive was not detected in this 18-month clinical trial.     

Influence of enamel wetness on resin composite restorations using various dentine bonding agents: part I-effects on marginal quality and enamel microcrack formation

OBJECTIVES: To investigate the influence of enamel wetness on marginal quality and enamel microcrack formation using various dentine bonding adhesives; and to determine the changes of marginal quality and enamel microcracks over time. METHODS: Forty extracted molars were each prepared with a cylindrical cavity and divided into five groups. Groups 1-4 were acid-etched and treated separately with either an ethanol-based adhesive (Single Bond) or an acetone-based adhesive (Prime&Bond NT) on either dry or wet enamel. Teeth in Group 5 were treated with a self-etching adhesive (Clearfil SE Bond). Epoxy replicas of different stages were taken after cavity preparation, after restoration, after 24 h storage, and after thermocycling test. These replicas were examined under a scanning electron microscope for their restorative marginal quality and enamel microcrack. Quantitative measurement was performed to measure the length ratio of different margin patterns, and enamel microcracks. RESULTS: There was no difference in the marginal quality when ethanol-base adhesive was applied on dry or wet dentin. The group using acetone-based adhesive on the dry enamel presented higher intact margin ratio than the group on wet enamel did only after restoration. Using self-etching primer led to higher open margin ratio at all stages. Enamel microcracks were found in all five groups and were higher in groups using acetone-based adhesives. CONCLUSION: Enamel wetness did not show a significantly adverse effect on the marginal quality of the restorations using either acetone- or ethanol-based adhesive. Using self-etching adhesive may lead to high incidence of margin deterioration.     

A 36-month evaluation of self-etch and etch-and-rinse adhesives in noncarious cervical lesions

BACKGROUND: There are two bonding strategies for composite restorations: the etch-and-rinse (ER) approach and the self-etch (SE) approach. Few clinical trials have evaluated the SE approach in Class V restorations for a 36-month period. The authors conducted a study to evaluate whether the SE system can provide retention rates and marginal discoloration similar to that of the ER system. METHODS: Twenty-five patients, each having at least two pairs of equivalent noncarious cervical lesions under occlusion, were enrolled in this study. Two calibrated operators placed 78 restorations, one-half for ER and one-half for SE. Two independent examiners evaluated the restorations at baseline and after six-, 12-, 18- and 36-month periods according to the slightly modified U.S. Public Health Service criteria. Statistical analysis between materials in each period was conducted using a Fisher exact test (alpha = .05), and the performance of the materials at baseline in comparison with each period was evaluated by a McNemar test (alpha = .05). RESULTS: Five SE restorations and one ER restoration were lost after 36 months. After 36 months, 10 SE and five ER restorations were rated Bravo in marginal adaptation (P > .05). Fourteen SE and five ER restorations were rated Bravo in marginal discoloration (P < .05). CONCLUSIONS: Although a significantly increased marginal discoloration was observed with SE, both adhesives showed retention rates in noncarious cervical lesions that were not statistically different after 36 months. CLINICAL IMPLICATIONS: The ER and SE adhesive systems can be used with confidence; however, SE adhesive showed a faster and more progressive enamel marginal degradation.     

Comparative clinical evaluation of different treatment approaches using a microfilled resin composite and a compomer in Class III cavities: two-year results

This study evaluated the 24-month clinical performance of a microfilled composite using a one-bottle bonding system and a compomer that uses one-bottle bonding systems, which include a non-rinse conditioner or 36% phosphoric acid gel in Class III cavities. Each patient received three restorations due to primary caries of the anterior teeth, resulting in a total of 96 restorations. Three types of restoration/adhesive combinations were used: a microfilled resin composite (Filtek A110) with a one-bottle bonding system (Single Bond); a polyacid-modified resin composite (compomer) (Dyract AP) with a filled one-bottle bonding system (Prime & Bond NT) using 36% phosphoric acid pretreatment and a polyacid-modified resin composite (compomer) (Dyract AP) with a filled one-bottle bonding system (Prime & Bond NT) using a non-rinse conditioner (NRC) and a self-priming pretreatment. At baseline and one- and two-year recalls, color match, marginal discoloration, wear or loss of anatomical form, caries, marginal adaptation and surface texture of the restorations were evaluated by two experienced, calibrated examiners using the modified Ryge criteria. After two years, one restoration from each group had a rating of Charlie (C) for both color match and marginal discoloration and needed to be replaced. Therefore, the failure rate was 3.6% (success rate: 96.4%) for each group at the end of two years. Statistical analysis showed no significant differences among the three groups in color match, marginal discoloration, wear or loss of anatomical form, marginal adaptation and surface texture after two years. Also, no statistically significant differences were determined for each group with respect to color match, marginal discoloration, wear or loss of anatomical form, marginal adaptation and surface texture at the end of two years.     

Application of etch-and-rinse adhesives on dry and rewet dentin under rubbing action: a 24-month clinical evaluation

BackgroundResearchers conducting laboratory investigations have reported that bonding to dry demineralized dentin can be feasible technically as long as the adhesives are rubbed vigorously onto the dentin surface. The authors aimed to evaluate the 24-month clinical performance of resin–based composites in noncarious cervical lesions (NCCLs) in teeth restored with two etch-and-rinse adhesives that had been applied with a vigorous rubbing action to both dry and rewet dentin.MethodsThe authors enrolled 40 patients in this study. They inserted 160 restorations and evaluated them at baseline and at six, 12 and 24 months of service. They divided the restorations into four groups: One-Step (OS) Universal Dental Adhesive System (Bisco, Schaumburg, Ill.) (acetone-based adhesive) with rewet dentin; OS with dry dentin; Adper Single Bond (SB) Plus Adhesive (3M ESPE, St. Paul, Minn.) (ethanol/water–based adhesive) with rewet dentin; and SB with dry dentin. The authors used the same resin–based composite for all restorations. They evaluated the restorations according to modified U.S. Public Health Service criteria.ResultsThe 24-month retention rates for the rewet and dry conditions, respectively, were 95.0 percent and 97.5 percent for SB and 97.5 percent and 91.9 percent for OS. The authors detected no significant difference between rewet and dry groups for either adhesive (P > .05). In terms of marginal discoloration, OS performed significantly worse than did SB, irrespective of dentin moisture (P > .05).Conclusions and Clinical ImplicationsDentin moisture seems not to be important for the retention of etch-and-rinse adhesives as long as the adhesives have been rubbed vigorously onto the dentin surface. The ethanol/water–based adhesive showed a better overall performance than did the acetone–based system.     

Influence of water-storage time on the sorption and solubility behavior of current adhesives and primer/adhesive mixtures

This study evaluated the effects of water-storage on the water sorption and solubility behavior of five commercially available dental adhesive systems and two primer/adhesive mixtures. The adhesives comprised three different approaches to bonding to hard tooth tissues: a one-step self-etching adhesive (One-up Bond F), two two-step self-etching primers (Clearfil SE Bond and Clearfil Protect Bond) and two etch-and-rinse systems: a water/ethanol-based (Single Bond) and an acetone-based filled adhesive (Prime&Bond NT). The bonding agents and primers of the two-step self-etching systems were mixed in a 1:1 volume ratio. Water sorption and solubility values were determined after 1, 7, 30, 90 and 180 days. The results showed that, except for SB, all adhesives presented increased water sorption with increased storage time. The one-step self-etching adhesive and self-etching primer/adhesive mixtures presented the highest water sorption and solubility values. Equilibrium in the water sorption values was observed for all adhesives after 90 days of water-storage. However, solubility values continued to increase for some materials until 180 days. The sorption and solubility behavior of the materials tested seem to be related to hydrophilicity of the adhesive resin solution and might influence the long-term performance of resin-based composite restorations.     

Effect of solvent type on microtensile bond strength of a total-etch one-bottle adhesive system to moist or dry dentin

This study evaluated the effect of organic solvent (acetone or ethanol) on the microtensile bond strengths (MTBS) of an adhesive system applied to dry and moist dentin. Sixteen extracted human third molars were ground to expose a flat occlusal dentin surface and acid etched for 20 seconds (20% phosphoric acid gel, Gluma Etch 20 Gel, Heraeus/Kulzer). After rinsing the acid etchant, an ethanol-based one-bottle adhesive system was applied to the mesial half of the occlusal dentin surface. An acetone-based, one-bottle adhesive system was applied to the distal half of the ground dentin surface. The teeth were randomly assigned to groups. In Group 1, the etched dentin was thoroughly air dried and an ethanol-based one-bottle adhesive system was applied (Gluma Comfort Bond, Heraeus/Kulzer) (GCB). In Group 2, the etched dentin was thoroughly air dried and an acetone-based one-bottle adhesive system was applied (Gluma One Bond, Heraeus/Kulzer)(GOB). In Group 3, excess moisture was removed after acid etching, leaving a moist dentin surface and a one-bottle ethanol-based adhesive was applied (Gluma Comfort Bond). In Group 4, excess moisture was removed after acid etching, leaving a moist dentin surface and an acetone-based adhesive was applied (Gluma One Bond). A hybrid resin composite (Venus, Heraeus/Kulzer) was applied to the bonded surface in four 1-mm increments and light cured according to manufacturer's directions. The specimens were then sectioned with a slow-speed diamond saw in two perpendicular directions to obtain sticks with a cross-section of 0.5 +/- 0.05 mm2. The microtensile bond strength (MTBS) test was performed with a Bencor device in an Instron machine at a crosshead speed of 0.5 mm/minute. The data were subjected to a two-way ANOVA and Scheffé Post hoc test (p < 0.05). The experimental MTBS measured for dry dentin were Group 1 = 37.0 +/- 10.6 and Group 2 = 34.7 +/- 9.0 in MPa (mean +/- SD); and on moist dentin, Group 3 = 50.7 +/- 11.0 and Group 4 = 38.5 +/- 10.5 in MPa (mean +/- SD). The ethanol based adhesives resulted in higher MTBS than acetone-based adhesive (p < 0.008) and bonding to moist dentin resulted in higher MTBS (p < 0.001). GCB applied on moist dentin resulted in statistically higher bond strengths than the other groups. The highest MTBS were achieved with the use of an ethanol-based adhesive to moist dentin.     

Eighteen-month clinical evaluation of two dentin adhesives applied on dry vs moist dentin

PURPOSE: To evaluate the influence of substrate moisture on the clinical behavior of two dentin adhesives after 18 months. The null hypothesis tested was that drying dentin with air upon rinsing off the acid would not influence the clinical performance of two dentin adhesives as compared to leaving the preparation visibly moist. MATERIALS AND METHODS: Thirty-five patients were enrolled in this study. One hundred twenty-eight restorations divided into 4 groups were inserted and evaluated at baseline: (1) NT/Moist - Prime & Bond NT, an acetone-based adhesive, applied on moist dentin; (2) NT/Dried - Prime & Bond NT applied on dentin dried with air for 3 to 4 s; (3) SB/Moist - Single Bond, an ethanol- and water-based adhesive, applied on moist dentin; (4) SB/Dried - Single Bond applied on dentin dried with air for 3 to 4 s. A microfilled composite resin was used for all restorations. Patients were recalled at 6 and 18 months. RESULTS: At 18 months after initial placement, 110 restorations (86% recall rate) were re-evaluated. Retention rates at 18 months were 92% for NT/Moist, 93% for NT/Dried, 100% for SB/Moist, and 89% for SB/Dried. No statistically significant differences were found among groups for retention rate. Both NT/Moist and SB/Moist resulted in a significant decrease in sensitivity to air from baseline to 18 months. When data were pooled for the variable "substrate moisture", SB resulted in an overall retention rate of 95%, while NT resulted in a retention rate of 92% (statistically similar). The marginal adaptation with SB was significantly worse at 18 months than at baseline. CONCLUSION: The moisture level of the dentin substrate in noncarious cervical lesions does not influence retention of composite restorations, but moist conditions caused less sensitivity to air. When applied as per manufacturers' instructions (moist dentin), both adhesives resulted in Class V retention rates exceeding the ADA 18-month full acceptance guidelines.     

Dentin bond strength and marginal adaptation: direct composite resins vs ceramic inlays.

The aim of this in vitro study was to compare the dentin bond strength and marginal adaptation of directly and indirectly inserted restorations. A conically modified push-out test was designed to consider polymerization shrinkage and facilitate inlay placement. A total of 260 cavities were prepared into disks of freshly extracted human third molars and filled with direct composite resins or with adhesively luted ceramic inlays. Dentin adhesives of the third--(with self-etching primer: ART Bond, Syntac Classic), fourth--(with total etching: Scotchbond Multi-Purpose Plus), and fifth-generation (one-bottle adhesives: Syntac Single Component, Prime & Bond 2.1) were used in combination with one hybrid composite (Tetric) or luting composite (Variolink Low). Control groups did not use an adhesive. Polymerization of the bonding agent was carried out prior to insertion of the filling/inlay or afterwards simultaneously with the composite/luting composite. The thickness of the adhesive layer and luting composite was recorded, and after 7 days of storage and 24 hours of thermocycling (1150 cycles) replicas were made and extrusion testing performed. Fracture modes were determined and replicas were examined regarding marginal adaptation using SEM (X200 magnification). Precuring of the bonding resin increased dentin bond strength independent of the material combination or insertion mode (P < 0.05). In general, third- and fourth-generation dentin adhesives produced better results in bond strength and marginal adaptation than one-bottle systems (P < 0.05). In the third generation, ART Bond achieved significantly higher push-out values than Syntac (P < 0.05), but no better marginal adaptation. Cohesive fractures within the dentin were only observed in the inlay groups with precured resin. Precuring of the bonding resin is an important factor for both direct and indirect restorations. Nevertheless, precuring of the bonding resin prior to insertion of adhesive inlays cannot be recommended clinically, because the 120-micron luting spaces were too large. In simulated cavities, direct composite fillings with precuring achieved bond strengths similar to inlays without precuring. One-bottle adhesive systems performed poorly compared with multi-step adhesives of the third and fourth generation.     

The clinical performance of one- and two-step self-etching adhesive systems at one year

BACKGROUND: The author compared the clinical performance of a two-step self-etching adhesive system and a one-step self-etching adhesive system over one year. METHODS: Thirty-five patients with noncarious cervical lesions were enrolled in the study. The author restored 163 lesions using a two-step (Clearfil Protect Bond, Kuraray, Osaka, Japan) or a one-step (Xeno III, Dentsply/DeTrey, Konstanz, Germany) self-etching adhesive system. Enamel margins were not beveled, and no mechanical retentions were placed. The author evaluted the restorations at baseline and at three, six, nine and 12 months after placement using modified Ryge criteria for color-matching ability, marginal discoloration, marginal adaptation, initial caries formation, anatomical form, postoperative sensitivity and retention loss. RESULTS: The author assessed the changes in the parameters using the Cochran Q test and the McNemar test at a significance level of .05. At one year, the retention rates for the restorations in the two-step group were 100 percent; they were 96 percent for the restorations in the one-step group. Of the retained 75 restorations from the one-step group, two had marginal discoloration and slight anatomical form problems. In both groups, color-matching ability and postoperative sensitivity remained excellent. CONCLUSION: The performance of both self-etching adhesive systems was excellent during this one-year clinical trial. However, the two-step system exhibited slightly better retention than the one-step system. CLINICAL IMPLICATIONS: The one- and two-step self-etching adhesive systems evaluated in this study provided excellent clinical retention in noncarious lesions without mechanical retention.     

Two-year clinical evaluation of resinous restorative systems in non-carious cervical lesions

This controlled clinical trial evaluated the 2-year clinical performance of a one-bottle etch-and-rinse adhesive and resin composite system (Excite/Tetric Ceram) compared to a resin-modified glass ionomer cement (RMGIC) (Vitremer/3M) in non-carious cervical lesions. Seventy cervical restorations (35 resin composite - RC- restorations and 35 RMGIC restorations) were placed by a single operator in 30 patients under rubber dam isolation without mechanical preparation. All restorations were evaluated blindly by 2 independent examiners using the modified USPHS criteria at baseline, and after 6, 12 and 24 months. Data were analyzed statistically by Fisher's exact and McNemar tests. After 2 years, 59 out of 70 restorations were evaluated. As much as 78.8% retention rate was recorded for RC restorations, while 100% retention was obtained for RMGIC restorations. Fisher's exact test showed significant differences (p=0.011) for retention. However, there were no significant differences for marginal integrity, marginal discoloration, anatomic form and secondary caries between the RC and RMGIC restorations. The McNemar test detected significant differences for Excite/TC between baseline and the 2-year recall for retention (p=0.02), marginal integrity (p=0.002) and anatomic form (p=0.04). Therefore, the one-bottle etch-and-rinse bonding system/resin composite showed an inferior clinical performance compared to the RMGIC.     

A randomized controlled clinical trial of a HEMA-free all-in-one adhesive in non-carious cervical lesions at 1 year

OBJECTIVES: One-step self-etch adhesives are the most recent generation of adhesives introduced onto the market. The objective of this randomized controlled clinical trial was to test the hypothesis that a one-step self-etch adhesive performs equally well as a conventional three-step etch&rinse adhesive (gold standard). METHODS: Fifty-two patients had 267 non-carious cervical lesions restored with Gradia Direct Anterior (GC). These composite restorations were bonded either with the 'all-in-one' adhesive G-Bond (GC) or with the three-step etch&rinse adhesive Optibond FL (Kerr). The restorations were evaluated after 6 and 12 months clinical service regarding their retention, marginal integrity and discoloration, caries occurrence, preservation of tooth vitality and post-operative sensitivity. Retention loss, severe marginal defects and/or discoloration that needed intervention (repair or replacement) and the occurrence of caries were considered as clinical failures. A logistic regression analysis with generalized estimating equations was used to account for the clustered data (multiple restorations per patient). RESULTS: The recall rate at 1 year was 98%. The statistical analysis revealed a relatively low patient factor, indicating that supplementary information could be obtained from the additional restorations placed per patient. The retention rate for G-Bond was 98.5% compared to 99.3% for Optibond FL, due to the retention loss of two and one restorations, respectively. There were no significant differences between the two adhesives regarding the evaluated parameters except for the presence of small enamel marginal defects with G-Bond. CONCLUSIONS: After 12 months, the simplified one-step G-Bond and the three-step Optibond FL were clinically equally successful, even though both adhesives were characterized by progressive degradation of marginal adaptation, and G-Bond exhibited more small enamel marginal defects.     

Clinical evaluation of three adhesive systems in class V non-carious lesions.

OBJECTIVES: The purpose of this study was to evaluate the clinical retention of three new adhesive systems in non-carious cervical lesions during a 3-year period. METHODS: The adhesive systems, a three-step (EBS/Pertac Hybrid), a one-bottle resin bonding agent (One-Step/Pertac Hybrid) and a resin-modified glass ionomer cement (Fuji II LC) were placed in 148 non-carious cervical lesions, 87 with sclerotic dentin and 61 non-sclerotic. Of the sclerotic lesions treated with the two resin bonding systems, 37 were slightly roughened with a diamond bur before conditioning. The restorations were evaluated every 6 months during a 3-year period. RESULTS: All except six restorations were evaluated during the 3 years. The cumulative loss rates for EBS, One-Step and Fuji II LC were, at 1 year: 2, 24 and 2% and at 3 years: 10, 49, 7%, respectively. The one-bottle adhesive showed significantly more failures. The five lost EBS restorations were found in non-sclerotic lesions, while the three lost Fuji II LC restorations had been placed in sclerotic lesions. For the One-Step material the loss frequency for non-sclerotic versus sclerotic lesions was 31.8 and 65.2%, respectively. Slight roughening of the sclerotic dentin surfaces with a diamond bur did not increase retention of the restorations. SIGNIFICANCE: The three-step resin adhesive and the RMGIC showed clinically acceptable retention rates, while a high failure rate was registered for the one-bottle adhesive.     

Three-year clinical performance of a HEMA-free one-step self-etch adhesive in non-carious cervical lesions

Despite the fact that one-step adhesives are currently used routinely in clinical practice, long-term studies on their clinical performance are scarce. The objective of this randomized controlled clinical trial was to test the hypothesis that a 2-hydroxyethyl methacrylate (HEMA)-free one-step self-etch adhesive performs worse than a conventional multistep etch-and-rinse adhesive. Two-hundred and seventy-six non-carious cervical lesions in 52 patients were restored with a micro-hybrid composite (Gradia Direct; GC). These restorations were bonded in random order either with the HEMA-free one-step adhesive G-Bond (GC) or with the 'gold-standard' (control) three-step adhesive Optibond FL (Kerr). The restorations were evaluated after 6, 12, 24, and 36 months of clinical service regarding retention, marginal adaptation, microleakage, caries occurrence, and sensitivity. After a medium-long period of 3 yr, similar success in clinical performance was observed for the simplified all-in-one adhesive and the conventional three-step adhesive. However, the one-step adhesive exhibited significantly more incisal marginal defects and discolorations. Whereas marginal degradation appeared to arrest for the multistep etch-and-rinse adhesive after 12 months, the enamel margins of the restorations bonded with the one-step self-etch adhesive continued to deteriorate. These incisal marginal defects were, however, small and could easily be removed by polishing. For both adhesives, large and sclerosed lesions appeared to be at higher risk of retention loss.     

Clinical evaluation of etched porcelain onlays: a 4-year report

Etched porcelain-bonded-to-enamel restorations (porcelain veneers) have demonstrated a low incidence of debonding, fracture, microleakage, and discoloration. In addition, laboratory and short-term clinical studies have shown satisfactory results with posterior etched porcelain-bonded restorations. This study evaluated the 4-year clinical performance of posterior all-ceramic onlays and overlays bonded with a dual-cure luting resin and a self-cure acetone-based dentinal adhesive. Twenty-one posterior porcelain overlay restorations were fabricated from a high-leucite-content porcelain and bonded to the teeth of 12 adults using a dual-cure luting resin and an acetone-based self-cure N(P-tolyl) glycine-glycdyl methacrylate (NTG-GMA), pyromellitic acid dianhydride and 2-hydroxyethyl methacrylate (PMDM) dentinal adhesive. Restorations were examined for retention, marginal caries, marginal microleakage, sensitivity, discoloration, restorative fracture, and patient satisfaction. Data collected at 4 years revealed 100% retention of the restorations with no marginal discoloration, marginal ditching, caries, or sensitivity. A small gap (Ryge UPHS rating of Bravo) was detected at the facial margin of one restoration but was not sufficient enough to require repair or replacement. Each patient reported a very high level of satisfaction with the restorations. This study demonstrates that porcelain overlays with supragingival margins entirely on enamel that rely primarily or entirely on bonding for their retention can provide excellent esthetics, good function, and perhaps long-term durability if properly designed, fabricated, and bonded. Porcelain overlays fabricated from high-leucite-content porcelain bonded to sound enamel and dentin with a dual-cure luting resin and a fourth generation dentinal adhesive provide satisfactory clinical results and high patient satisfaction.     

自酸蚀和酸蚀-冲洗粘结剂对Ⅰ类洞复合树脂充填的2年临床评价

目的:评价酸蚀-冲洗粘结剂和自酸蚀粘结剂在后牙I类洞修复中的临床效果。方法:共25名后牙患龋的患者入选了本次临床试验。每位患者随机接受了至少2颗后牙I类洞的修复,68例患牙随机分为2组,实验组采用自酸蚀粘结剂+复合纳米树脂修复(Adper Easy One+Filtek Z350,3M ESPE)38例,对照组使用全酸蚀牙本质粘结剂+复合纳米树脂修复(Adper Single Bond 2+Filtek Z350,3MESPE)30例。在充填后即刻、术后6个月、1年和2年时,根据改良的USPHS量表,从保存率、术后敏感、颜色匹配、边缘染色、边缘完整性、解剖形态、继发龋和表面质地7个方面对每个修复体都进行评分。结果:在复查的2年内,全酸蚀和自酸蚀组的保存率分别为100%和90.6%,其他各项指标亦均无显著性差异。结论:自酸蚀粘结剂和全酸蚀粘结剂用于修复后牙Ⅰ类洞均可获得较理想的临床效果。