Thirty-six-month follow-up of cervical composite restorations placed with an MDP-free universal adhesive system using different adhesive protocols: a randomized clinical trial

Clinical Oral Investigations - To evaluate the influence of different application strategies on the clinical behavior of an MDP-free universal adhesive placed in non-carious cervical lesions...     

Porcelain to dentin bond strength with a dentin adhesive.

Adhesion of porcelain to dentin may be important in those cases with little remaining enamel. The purpose of this study was to determine the bond strength of porcelain to dentin using a dentin adhesive (All-Bond) and compare it to the enamel bond strength. Sixty human molar teeth had either a dentin or enamel bonding site prepared by flat grinding to a 600 grit. The teeth were divided into three groups of 20 each. Sixty porcelain cylinders were prepared, hydrofluoric acid etched on one end and silane treated. Twenty of the cylinders were bonded to enamel, 20 bonded to dentin with a dentin adhesive to be tested at 48 hours, and 20 bonded to dentin with a dentin adhesive to be tested after 24 hours of thermocycling (800 cycles at 6 degrees C to 60 degrees C). The specimens were tested in an Instron at a crosshead speed of 0.5 mm/minute. The following bond strengths were found: enamel (19.0 +/- 2.9 MPa), dentin at 48 hours (14.4 +/- 5.4 MPa), and dentin after thermocycling (10.1 +/- 3.8 MPa). When this data was subjected to statistical analysis (ANOVA), there was a significant difference between the groups. A Scheffe's test found that the dentin-porcelain bond at 48 hours was stronger than the thermocycled group, and that the enamel bond was significantly stronger than the two dentin bonds.     

Bonded amalgam restorations: using a glass-ionomer as an adhesive liner

Due to the lack of adhesiveness of amalgam to tooth structure, several adhesive cements have been utilized in bonded amalgam restorations. This study evaluated whether Fuji-II glass-ionomer cement is an appropriate adhesive liner in bonded amalgam restorations. Two adhesive composite luting cements (Amalgambond Plus and Panavia-21) and Copalite cavity liner were compared. The study was conducted in two phases. In the first part, we quantitatively assessed the tensile bond strengths as well as the failure modes of amalgam bonded to human dentin, using different adhesive liners. In each group, the flat dentin surface was treated with the assigned adhesive cement with a Teflon mold, followed by condensation of amalgam (Valiant PhD) onto it. Each group's mean tensile bond strengths were recorded and the statistical analysis by one way ANOVA showed no significant differences among groups (p > 0.05). Similar to the fracture patterns of the Amalgambond Plus and Panavia-21 groups, the failure mode of Fuji-II group was predominantly adhesive fracture. In the second part, the fracture strengths of amalgam restored teeth were measured using different adhesive liners. Standard MOD cavities were prepared in each tooth except for the intact tooth group. After treatment with the assigned adhesives or varnish, the cavities were restored with amalgam. Fracture strengths were then measured and the fractured interfaces examined using a scanning electron microscope. The fracture strengths of the intact tooth, Amalgambond Plus, Panavia-21 and Fuji-II groups were significantly higher than those of the Copalite and prepared cavity without restoration groups (p < 0.01). Accordingly, Fuji-II glass-ionomer cement, when used as an adhesive liner of amalgam restoration, may effectively reinforce the remaining tooth structure and, therefore, enhance the fracture resistance of the amalgam-restored teeth.     

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.     

The effect of dentin adhesive and cure mode on film thickness and microtensile bond strength to dentin in indirect restorations

This study evaluated the influence of dentin adhesive application technique (pre-curing vs non precuring) on microtensile bond strength (microTBS) to dentin and adhesive layer thickness in indirect resin restorations. Seven proprietary dentin adhesives were tested, including one-step and multistep products. Experimental groups included adhesive pre-cure (PC) with a halogen light source and no pre-cure (NPC) prior to resin cement insertion. Thirty caries-free molars received an MO inlay preparation. Inlays made with Tetric Ceram resin composite were cemented using a dual-cured resin luting agent. Prior to inlay cementation, each tooth was treated with one dentin bonding agent, using pre-cure (PC) or no pre-cure (NPC). After storage in distilled water at 37 degrees C for 24 hours, the teeth were sectioned along their long axis to produce serial sticks for microtensile bond strength testing at 0.5 mm/minute. The results were subjected to statistical analysis by one-way and two-way analysis of variance (ANOVA) and Tukey's multiple comparison test (p < or = 0.05). For the film thickness evaluation, 10 additional teeth were restored and sectioned mesiodistally. The thickness of the adhesive layer was evaluated by SEM at 1000x magnification at the pre-selected locations. The microTBS varied from 11.7 +/- 4.5 MPa to 43.4 +/- 9.8 MPa. The effect of pre-curing the adhesive was material specific. No adhesive layer was visualized for the adhesives used without the pre-curing step. The thickness of the adhesive layer for the pre-cured groups varied according to the different areas analyzed.     

Amalgam and ART restorations in children: a controlled clinical trial

Objectives

The aims of this study were to compare 2-year cumulative survival rates of amalgam and atraumatic restorative treatment (ART) restorations in primary molars and to investigate the determinants of the survival rate of restorations.

Materials and methods

A controlled clinical trial using a parallel group design was carried out on 258 children aged 6–7 years old, allocated to two treatment groups: conventional restorative treatment using amalgam and ART using high-viscosity glass ionomer. A total of 364 amalgam restorations and 386 ART restorations were placed by three pedodontists in 126 and 158 children, respectively, and were evaluated after 0.5, 1, and 2 years. Restorations were placed in vital primary molars with neither pain nor signs of pulp involvement. The survival analysis was conducted using the proportional hazard rate regression model with frailty correction.

Results

The 2-year cumulative survival rates for all amalgam (77.3 %) and ART (73.5 %) restorations were not statistically significantly different, but there was an effect of “type of surface” (single/multiple) and “cavity filling time” on the survival rates. Both amalgam and ART single-surface restorations had higher survival rates than multiple-surface restorations of the same material. Secondary caries was responsible for 36 and 38 % of failures in amalgam and ART restorations, respectively. Mean time for restoring all type of cavities with amalgam and ART restorations was 13.6 and 13.7 min, respectively.

Conclusions

Amalgam and ART restorations presented similar survival rates over a 2-year period for all, single-surface, and multiple-surface restorations.

Clinical relevance

In the cause of finding alternatives to amalgam, ART restorations using high-viscosity glass ionomer might be a suitable option for managing cavitated dentine carious lesions in vital primary molars.     

Effect of a resin-based desensitizing agent and a self-etching dentin adhesive on marginal leakage of amalgam restorations

AIM: The purpose of this study was to compare the marginal leakage of Class II amalgam restorations whose preparations were lined with a resin-based desensitizing agent, a self-etching adhesive system, and copal varnish. METHODS AND MATERIALS: Fifty-six freshly extracted human premolar teeth were divided into four groups. A Class II preparation was prepared with only a proximal box on the mesial and distal surfaces of each tooth. The cavities in one group were lined with a desensitizing agent (VivaSens) and a second group with an adhesive (Clearfil S3 Bond). A third group was lined with copal varnish (Copalite) and a fourth group was used as the control without any cavity liner. Spherical high copper amalgam was hand-condensed into each preparation, specimens were thermocycled, stained, and sectioned. Microleakage was graded using a stereomicroscope. Microleakage scores were calculated and analyzed using the Kruskal Wallis and the Mann-Whitney tests (alpha=0.05). RESULTS: Less microleakage was indicated with the VivaSens liner when compared with the other groups (P<0.05). Clearfil S3 Bond showed less microleakage than the control group (P<0.05), but the leakage with copal varnish and Clearfil S3 Bond was similar (P>0.05). CONCLUSION: VivaSens reduced the microleakage of Class II high copper amalgam restorations significantly more than the Clearfil S3 Bond and copal varnish.     

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.     

Fiber post adhesion to radicular dentin: The use of acid etching prior to a one-step self-etching adhesive

The aim of this study was to evaluate the bond strength of fiber posts luted with a one-step self-etching adhesive with the push-out test after phosphoric acid conditioning of the root dentin. Thirty-six single-rooted teeth were endodontically treated. Teeth were sectioned perpendicularly to the cementoenamel junction, and a 10-mm post space was prepared with a calibrated bur. Specimens were then divided into three groups according to the adhesive protocol: A, total-etch three steps; B, self-etch one step; and C, 32% phosphoric acid conditioning and self-etch one step. Fiber posts were luted with self-curing resin-based cement. Teeth were cut in 1-mm slices and pushed until failure with an Instron machine. Results were statistically analyzed with the ANOVA and Bonferroni tests (P < .05). Two additional specimens from each group were examined under the scanning electron microscope (SEM). The 32% phosphoric acid significantly influenced the push-out bond strength of fiber posts luted with self-etch adhesives (P < .05). SEM analysis showed a continuous hybrid layer with resin tags and lateral branches in groups A and C, while group B showed smear layer dissolution with poor infiltration of the tubules.     

评价新型粘接剂在不同粘接模式下的牙本质粘接性能

目的评价1种新型单瓶型多模式粘接剂在不同粘接模式下与牙本质的粘接强度和粘接耐久性。方法制作3组牙本质/复合树脂粘接试件,其中每组牙本质在粘接前接受不同的表面调节。包括不处理(空白对照),Singlebond Universal粘接剂自酸蚀模式下调节牙本质,Singlebond Universal粘接剂在酸蚀冲洗模式下调节牙本质。测量各组粘接试件水储24 h和180 d的微拉伸粘接强度值并进行统计分析。以扫描电子显微镜观察各组试件的粘接界面。结果不论老化前还是老化后,3组间的粘接强度均存在显著性差异,其中空白组的粘接强度值最低,另两组间则无显著性差异。人工老化使空白组的粘接强度值显著下降,而对另两组则并无显著影响。结论 Singlebond Universal粘接剂在自酸蚀粘接模式和酸蚀冲洗粘接模式下均能够形成与牙本质良好的粘接。     

两种牙本质粘接剂修复牙颈部非龋性缺损两年的临床观察

目的评价两种牙本质粘接系统修复牙颈部非龋性缺损两年的临床效果。方法临床完成23例患者的30颗牙颈部非龋性缺损的修复,其中男性11例,女性12例,年龄35～55岁。修复用两种粘接系统分别为Scotchbond Multi-Purpose和Adper Prompt L-Pop,修复树脂为Z250,以改良的USPHS标准评价修复后两年的随访结果。结果Scotchbond Multi-Purpose和Adper Prompt L-Pop两组在各个复查阶段均没有出现C或D的结果,两年的修复成功率均为100%。结论Scotchbond Multi-Purpose和Adper Prompt L-Pop与相应的修复树脂对牙颈部非龋性缺损的临床修复效果稳定。     

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.     

Long-term use of dentine adhesive as an interfacial sealer under Class II amalgam restorations

An in vitro study was carried out to evaluate the long-term sealing properties of a light-cured dentine adhesive in Class II amalgam restorations. The restorations were subjected to repeated vertical occlusal loads and a number of thermocycling procedures. The results demonstrated significant advantages of using a dentine adhesive as an interfacial sealer in order to reduce microleakage, compared to a conventional Copal varnish.     

Phosphoric acid as a dentin etchant.

This study determined the effect of phosphoric acid (H3PO4) application to dentin on the shear bond strength (SBS) and microleakage of an experimental bonding system. Thirty human maxillary permanent first and second molars were used for the SBS evaluation. In 15 of the teeth the Dentin Conditioner was applied to dentin for 30 seconds (A), while in the remaining 15 teeth the smear layer was removed by the application of a 37% H3PO4 gel for 20 seconds (B). The Primers 1 and 2 were mixed and applied to the conditioned dentin followed by the application of the Dentin Bonding Resin prior to the placement in three increments of the Bisfil-M composite. The specimens were stored in physiological saline at 37 degrees C for 24 hours prior to applying a shear load at a crosshead speed of 0.5 mm. inch-1 in an Instron machine. Shear bond strengths were expressed in MPa. Circular Class V preparations were made on the roots of 30 maxillary permanent canines, 15 restored using the Dentin Conditioner (C) and 15 by removing the smear layer with the H3PO4 gel (D). Microleakage of the restorations was determined quantitatively by means of a spectrophotometric method. The quantitative microleakage was expressed as microgram dye/restoration. The data were analyzed by the Student t-test. The following results were obtained: A: 14.2 +/- 2.2 MPa; B: 7.2 +/- 4.2 MPa; C: 30.0 +/- 28.6 micrograms dye/restoration; (D) 10.3 +/- 8.2 micrograms dye/restoration. Removing the smear layer with H3PO4 reduced the SBS to dentin but decreased the quantitative microleakage significantly.     

Influence of acid etching and enamel beveling on the 6-month clinical performance of a self-etch dentin adhesive

This study tested the hypothesis that beveling and/or etching enamel does not affect the 6-month clinical performance of the self-etch adhesive Clearfil SE Bond in class V noncarious lesions. With Institutional Review Board approval, 34 patients were enrolled in this study. A total of 120 noncarious cervical lesions were selected and assigned to 4 groups: (1) Clearfil SE Bond was applied without any cavity preparation; (2) After the enamel was beveled, Clearfil SE Bond was applied; (3) After the enamel was etched for 15 seconds with 35% phosphoric acid, Clearfil SE Bond was applied; (4) After the enamel was beveled and etched with 35% phosphoric acid for 15 seconds, Clearfil SE Bond was applied. A microfilled composite resin was used for all restorations. Six months after initial placement, 120 restorations (a 100% recall rate) were re-evaluated. Retention rates at 6 months were 100% for all groups. Sensitivity to air improved from baseline to 6 months, but the overall difference was not statistically significant. The 6-month retention rate of the self etch dentin adhesive system Clearfil SE Bond was not improved by enamel beveling or by enamel etching. For the self-etch material Clearfil SE Bond, instrumentation or etching of enamel may not be critical for its clinical performance at 6 months.