A randomized controlled 5-year prospective study of two HEMA-free adhesives,a 1-step self etching and a 3-step etch-and-rinse,in non-carious cervical lesions

Objective

The aim of this study was to evaluate the 5 year clinical dentin bonding effectiveness of two HEMA-free adhesives in Class V non-carious cervical lesions.

Material and methods

A total of 169 Class V restorations were placed in 67 patients with a self-etching adhesive (G-Bond; 67), a 3-step HEMA and TEGDMA free etch-and-rinse (cfm; 51) and a control HEMA-containing etch-and-rinse adhesive (XP Bond; 51) in non-carious cervical lesions without intentional enamel involvement. The restorations were evaluated at baseline and yearly during a 5 year follow-up with modified USPHS criteria. Dentin bonding efficiency was determined by the percentage of lost restorations.

Results

During the 5 years, 159 restorations could be evaluated. Good short time dentin retention was observed for the three adhesives, there all adhesives fulfilled at 18 months the full acceptance ADA criteria. At 5 years a cumulative number of 22 lost restorations (13.8%) was observed. The HEMA-free adhesives showed significantly higher dentin retention compared to the HEMA-containing one. Loss of retention was observed for 5 G-Bond (7.9%), 4 cfm (8.3%) and 13 XP Bond (27.1%) restorations (p < 0.05). No post-operative sensitivity was reported by the participants. No secondary caries was observed.

Significance

The durability in non-carious cervical lesions of the HEMA-free adhesives was successful after 5 years. Despite concerns which have been raised, showed the 1-step SEA one of the best reported clinical dentin bonding effectiveness.     

Effect of different adhesive systems and laser treatment on the shear bond strength of bleached enamel

Purpose

This study determined the shear bond strength of a nanohybrid composite resin to bleached enamel immediately or 15 days later using different adhesive systems and laser application.

Methods

One hundred and forty enamel specimens were prepared from human molar teeth and bleached either with 16% carbamide peroxide (CP) or 30% CP according to the manufacturer's (Vivastyle/Vivadent) recommendations. After bleaching treatments specimens were divided into two groups according to the treatment time of the adhesive procedures: immediately or 15 days after the bleaching treatments. The four groups were then divided into five subgroups due to the surface treatments: using a two-step self-etching adhesive (AdheSe, Ivoclar Vivadent G, Schaan, Liechtenstein) or a two-step etch and rinse adhesive (Excite, Ivoclar Vivadent G, Schaan, Liechtenstein) and application of laser prior to adhesive procedures or not. After adhesive procedures nanohybrid composite resin cylinders of 4 mm × 2 mm (Tetric Evo Ceram/Vivadent) were bonded to the enamel surfaces. All specimens were subjected to shear bond strength test after thermocycling and 24 h of storage in water. Data were analyzed statistically.

Results

Mann–Whitney U-test analysis showed no significant difference in the mean bond strength values of enamel bleached with either 16% CP or 30% CP (p > 0.05). There was no difference between the groups bonded immediately or 15 days after bleaching (p > 0.05). Application of the etch and rinse adhesive after 15 days showed the highest bond strength values, whereas self-etching adhesive and laser application showed the lowest values in both bleaching treatments.

Conclusions

The results suggested that following the bleaching treatments, the use of etch and rinse adhesive system may provide higher bond strengths than self-etching adhesive and laser application.     

One-year evaluation of two hybrid composites placed in a randomized-controlled clinical trial

Objective

The aim of this prospective randomized-controlled clinical trial is to assess the long-term performance of two direct composite resins in posterior teeth. This study provides a survey of the one-year results.

Materials and methods

A total of 1805 restorations were placed by students in stress-bearing Class I/II cavities (including cuspal-coverage) in molars and premolars in 456 patients. Clinical evaluation was performed at baseline and after one year using modified USPHS criteria. The restorations in each patient were performed either with Ceram X/Prime&Bond NT or Tetric Ceram/Optibond Solo Plus.

Results

After one year 528 fillings with Ceram X and 580 with Tetric Ceram were available for evaluation of substance loss, contact point, color match, marginal staining, marginal adaptation, secondary caries and radiographic examination (if necessary). This represents a recall rate of 61.18% (279 patients). The failure rate per material was 5.3% in the Ceram X group and 6.1% in the Tetric Ceram group. Most of the failures were associated with marginal adaptation/integrity of the filling. A significant influence on the occurrence of a failure was observed for the number of treated teeth per patient, the age of the patient, the mesio-distal extension of the restoration and the tooth position. Gender, material, a previous root canal treatment, the bucco-lingual extension of the filling or cuspal-coverage did not significantly influence the failure rate. Patients attending the first recall were significantly older and had more fillings than patients not attending.

Conclusions

In a group of Class I/II restorations (including cuspal-coverage), there was no significant difference in failure rates between ormocer-based and bis-GMA-based restorative systems after one year. A previous root canal treatment had no negative influence on the failure rate. A longer observation period is indicated to get clear evidence of the long-term performance of these composite resin systems.     

Correlation between microtensile bond strength data and clinical outcome of Class V restorations

Objective

To determine if the results of resin-dentin microtensile bond strength (μTBS) is correlated with the outcome parameters of clinical studies on non-retentive Class V restorations.

Methods

Resin-dentin μTBS data were obtained from one test center; the in vitro tests were all performed by the same operator. The μTBS testing was performed 8 h after bonding and after 6 months of storing the specimens in water. Pre-test failures (PTFs) of specimens were included in the analysis, attributing them a value of 1 MPa. Prospective clinical studies on cervical restorations (Class V) with an observation period of at least 18 months were searched in the literature. The clinical outcome variables were retention loss, marginal discoloration and marginal integrity. Furthermore, an index was formulated to be better able to compare the laboratory and clinical results. Estimates of adhesive effects in a linear mixed model were used to summarize the clinical performance of each adhesive between 12 and 36 months. Spearman correlations between these clinical performances and the μTBS values were calculated subsequently.

Results

Thirty-six clinical studies with 15 adhesive/restorative systems for which μTBS data were also available were included in the statistical analysis. In general 3-step and 2-step etch-and-rinse systems showed higher bond strength values than the 2-step/3-step self-etching systems, which, however, produced higher values than the 1-step self-etching and the resin modified glass ionomer systems. Prolonged water storage of specimens resulted in a significant decrease of the mean bond strength values in 5 adhesive systems (Wilcoxon, p < 0.05). There was a significant correlation between μTBS values both after 8 h and 6 months of storage and marginal discoloration (r = 0.54 and r = 0.67, respectively). However, the same correlation was not found between μTBS values and the retention rate, clinical index or marginal integrity.

Significance

As μTBS data of adhesive systems, especially after water storage for 6 months, showed a good correlation with marginal discoloration in short-term clinical Class V restorations, longitudinal clinical trials should explore whether early marginal staining is predictive for future retention loss in non-carious cervical restorations.     

Influence of chlorhexidine digluconate on the clinical performance of adhesive restorations: A 3-year follow-up

Objectives

The aim of this clinical study was to evaluate the long-term clinical performance of non-carious Class V restorations with and without application of chlorhexidine digluconate to acid-etched dentine.

Methods

After the approval of the Ethics and Informed Consent Committee, 70 non-carious cervical lesions were selected and randomly assigned into two groups, according to the split mouth design. The control group was restored with a two-step etch-and-rinse adhesive (Adper Single Bond 2) following manufacturer's instructions; whereas in the experimental group 2% chlorhexidine digluconate solution was applied to acid etched dentine for 30 s after etching and prior to the adhesive application. All lesions were restored with a nanofilled composite resin (Filtek Supreme XT) and polymerized with a light-curing unit operating at 600 mW/cm². Clinical performance was recorded after 1 week, 6, 12, and 36 months using modified Ryge/USPHS criteria in terms of retention, marginal discoloration, marginal integrity, post-operative sensitivity, and secondary caries incidence. Data were analyzed using Chi-Square, Fisher's exact test and McNemar tests (α = .05).

Results

After 36 months the control group showed a success rate of 88% in comparison to 76% of experimental group; however, no statistically difference between them was found (p = .463). Moreover, no statistical differences were observed between groups in the criteria post-operative sensitivity, marginal discoloration, marginal integrity, and secondary caries incidence between the two groups.

Conclusion

The addition of 2% chlorhexidine digluconate conditioning step does not improve the clinical durability of adhesive restorations.     

Clinical evaluation of the bulk fill composite QuiXfil in molar class I and II cavities: 10-year results of a RCT

Objective

The objective of this RCT was to compare the 10-year clinical performance of QuiXfil with that of Tetric Ceram in posterior single- or multi-surface cavities.

A 6-year prospective evaluation of a one-step HEMA-free self-etching adhesive in Class II restorations

Objective

The aim of this study was to evaluate the clinical effectiveness of a one-step HEMA-free self-etching adhesive (SEA) placed with a micro-fine hybrid resin composite in Class II restorations. The restorations were compared intraindividually with 2-step HEMA containing SEA-giomer restorations.

Material and methods

Fifty-four patients with at least one pair of two similar Class II cavities participated (30 men, 24 women; mean age 57.1 yrs). A total of 115 Class II composite restorations were placed with (1) a one step HEMA-free adhesive and a micro-fine hybrid resin composite (Gbond/Gradia Direct: 60; GG) and (2) a 2-step HEMA-containing SEA and a giomer (FL Bond/Beautifil: 55; FB). Each participant received in a randomized way at least one restoration with each of the experimental materials. The restorations were evaluated at baseline and yearly during a 6 year followup using modified USPHS criteria.

Results

During the 6 years, 111 restorations could be evaluated. No post-operative sensitivity was reported by the participants. Fourteen failed restorations (12.6%) were observed during the follow up, 5 GG (8.5%; 4 premolar and 1 molar teeth) and 9 FB (17.7%; 1 premolar and 8 molar teeth) (p < 0.05). Annual failure rate at 6 years were 1.4% for GB and 3.0% for FB. Main reasons of failure were bulk fracture of resin composite for FB and tooth fracture for GB.

Significance

The HEMA-free SEA-hybrid RC restorations showed good clinical durability in Class II cavities after 6 years. The HEMA-containing SEA-giomer restorations showed a rather high failure frequency.     

A split-mouth randomized clinical trial of conventional and heavy flowable composites in class II restorations

Objective

The aim of this study was to evaluate the 2-year clinical performance of class II restorations made with a composite resin with two different viscosities.

Methods

47 patients received two class II restorations (n = 94), one made with GrandioSO (conventional viscosity – CV), and the other with GrandioSO Heavy Flow (flowable viscosity – FV), subjecting both materials to the same clinical conditions. The self-etching adhesive Futurabond M was used for all restorations. The composites were inserted using the incremental technique. The restorations were evaluated using the modified USPHS criteria according to the periods: baseline, 6 months, 1 year and 2 years after restorative procedures.

Results

After 24 months, 40 patients attended the recall and 78 restorations were evaluated. In all periods, no secondary caries was observed. After 6 months, there were slightly overall changes of scores for most parameters. After 24 months, the higher number of changes from score Alfa to Bravo was observed for marginal discolouration (32.5% – CV and 39.5% – FV) and colour match (15% – CV and 31.6% – FV), followed by proximal contact (25% – CV and 23.7% – FV) and marginal adaptation (20% – CV and 21.1% – FV). For wear, surface texture and postoperative sensitivity the changes were very small. Just two restorations were lost during the 24-month follow up. Less than 5% of all restorations showed postoperative sensitivity. Chi-square test showed no significant differences between the two materials for all parameters analysed.

Conclusion

After 2 years of clinical service, no significant differences were observed between GrandioSO conventional and GrandioSO Heavy Flow for the parameters analysed. Both materials provided acceptable clinical behaviour in class II restorations.

Clinical Significance

This study presents the possibility of using a flowable composite with high filler content, for performing class II restorations.     

Four-year clinical evaluation of Class II nano-hybrid resin composite restorations bonded with a one-step self-etch and a two-step etch-and-rinse adhesive

Objective

The objective of this prospective clinical trial was to evaluate the 4-year clinical performance of an ormocer-based nano-hybrid resin composite (Ceram X; Dentsply/DeTrey) in Class II restorations placed with a one-step self-etch (Xeno III; Dentsply/DeTrey) and two-step etch-and-rinse adhesive (Ivoclar Vivadent).

Methods

Seventy-eight participants received at random at least two, as similar as possible, Class II restorations of the nano-hybrid resin composite bonded with either a single step self-etch adhesive or a control 2-step etch-and-rinse adhesive. The 165 restorations were evaluated using slightly modified USPHS criteria at baseline and then yearly during 4 years.

Results

162 restorations were evaluated at 4 years. Postoperative sensitivity was observed in 6 patients (3 Xeno III, 3 Exite) between 1 and 3 weeks. Eleven failed restorations (6.8%) were observed during the follow up. Seven in the one-step self-etch adhesive group (7.7%) and four in the 2-step etch-and-rinse group (5.6%). This resulted in non-significant different annual failure rates of 1.9% and 1.4%, respectively. Fracture of restoration was the main reason for failure.

Conclusion

The ormocer-based nano-hybrid resin composite showed a good clinical performance in Class II cavities during the 4 year evaluation. No significant difference was seen in overall clinical effectiveness between the two adhesives.     

Five-year clinical performance of the dentine Deproteinization Technique in non-carious cervical lesions

Objective

The aim of this study was to evaluate the 5-year clinical performance of composite restorations of non-carious cervical lesions (NCCL) using a total-etch adhesive system with or without collagen removal with 10% sodium hypochlorite (NaOCl).

Methods

In this study randomized controlled split-mouth clinical trial, one-hundred and thirty-eight NCCL were restored into 30 patients. Each patient received at least one pair of composite restorations (Filtek A110/3M ESPE), bonded either with 2 techniques: Conventional Technique – acid etching with 37% phosphoric acid + Prime & Bond NT (Denstply DeTrey); Deproteinization Technique – acid etching with 37% phosphoric acid + 10% NaOCl for 1 min + Prime & Bond NT. The two techniques were evaluated using the United States Public Health Service (USPHS) criteria at baseline, 18 months, 3 and 5 years. After five years, one-hundred and six restorations were evaluated in 24 patients. Data were analyzed using the Chi-Square test (p < 0.05).

Results

There were no statistically significant differences between the two techniques regarding the evaluated parameters (p > 0.05).

Conclusion

After 5 years, the application of 10% NaOCl deproteinization on etched dentine did not affect the clinical performance of composite restorations placed in NCCL when compared to the conventional total-etch technique.

Clinical significance

Clinical studies evaluating the performance of the Deproteinization Technique are scarce. In this study, this technique showed similar clinical performance at the end of 5 years when compared to a conventional total-etch technique.     

Two-year clinical evaluation of three adhesive systems in non-carious cervical lesions

Objectives

Adhesive systems are continuously being introduced to Dentistry, unfortunately often without sufficient clinical validation. The aim of this study was to evaluate the clinical performance of cervical restorations done with three different adhesive systems.

Material and methods

158 non-carious cervical lesions of 23 patients were restored with a nanofilled composite resin (Filtek Supreme, 3M/ESPE) combined with Single Bond (3M/ESPE, group SI), Clearfil SE (Kuraray Medical Inc., group CL) and Xeno III (De Trey Dentsply, group XE). In groups SI-B, CL-B and XE-B, the outer surface of the sclerotic dentin was removed by roughening with a diamond bur before application of the respective adhesive systems. In groups CL-BP and XE-BP, after removal of the outer surface of the sclerotic dentin with the bur, the remaining dentin was etched with 37% phosphoric acid and the self-etch adhesive systems Clearfil SE and Xeno III were applied, respectively. Lesions were evaluated at baseline, and restorations after 3 months, 1 year and 2 years using modified USPHS criteria.

Results

After 2 years, no significant difference was found between the retention rates of the groups (p >0.05). Although groups CL and SI showed significantly better marginal adaptation than group XE (p<0.05) at 2 years, no significant difference was found between the marginal adaptation of the groups SI-B, CL-B and XE-B (p>0.05). After 2 years no significant difference was observed among the marginal staining results of all groups (p>0.05).

Conclusion

Although all adhesive systems showed similar retention rates, Clearfil SE and Single Bond showed better marginal adaptation than Xeno III after 2 years of follow-up.     

Erosion and abrasion of tooth-colored restorative materials and human enamel

Objectives

The aim of this study was to investigate the effects of erosion and toothbrush abrasion on different restorative materials and human enamel.

Methods

Human enamel and 5 kinds of tooth-colored restorative materials were used. The restorative materials included three composite resins (Filtek Silorane, Tetric EvoCeram, and Tetric EvoFlow), a polyacid-modified composite (Dyract Extra), and a conventional glass-ionomer cement (Ketac Fil Plus). For each type of the material, 40 specimens were prepared and embedded in ceramic moulds and divided into four groups (n = 10): control group (C), erosion group (E), abrasion group (A), and erosion–abrasion group (EA). The specimens were subjected to six daily erosive attacks (groups E and EA; citric acid, pH 2.3, 1 min) and/or six abrasive attacks (groups A and EA; toothbrush abrasion, 100 strokes, 1 min), while the control specimens (group C) were maintained in artificial saliva. After 10-day treatment, the substance loss and surface changes were determined by surface profilometry and scanning electron microscopy.

Results

Human enamel presented higher substance loss when compared to restorative materials. Generally, combined erosion–abrasion (EA) caused the highest substance loss, followed by erosion, abrasion, and storage in artificial saliva. Composite resin presented highest durability under erosive and/or abrasive attacks. Enamel and restorative materials showed degradation in groups E and EA through SEM observation.

Conclusions

Toothbrush abrasion has a synergistic effect with erosion on substance loss of human enamel, polyacid-modified composite and glass-ionomer cement. The acid- and abrasive-resistance of human enamel was lower compared to restorative materials.     

Clinical Evaluation of a Nanohybrid and a Flowable Resin Composite in Non-carious Cervical Lesions: 24-Month Results

Purpose: To evaluate the 24-month clinical performance of cervical restorations using a nanohybrid and a flowable resin composite with a one-step self-etching adhesive. Materials and Methods: Twenty-one patients with at least one pair of non-carious cervical lesions participated in this study. A total of 134 non-carious cervical lesions were restored (67 with a nanohybrid resin composite, Grandio; 67 with a flowable resin composite, Grandio Flow) using a one-step self-etching adhesive system, Futura Bond NR, by one dentist. The restorations were evaluated for retention, color match, marginal discoloration, marginal adaptation, surface texture, anatomic form, and secondary caries by two calibrated examiners at baseline and after 6, 12, and 24 months using modified USPHS criteria. The survival rates of the restorations were calculated by the Kaplan-Meier estimator. The comparison of resin composites for each category was performed with the Pearson chi-square test, and the performance of restorations at baseline and after each recall time was evaluated using McNemar's test (p < 0.05). Results: All patients attended the 24-month recall. The retention rates at 6 months were 66% and 58%, and 61% and 57% at 12 months for Grandio and Grandio Flow, respectively. At the 24-month recall, the retention rate was 60% for Grandio and 54% for Grandio Flow. No statistically significant differences were found in retention rates among the restorative materials in any evaluation period (p > 0.05). For marginal discoloration and anatomical form, three Grandio and three Grandio Flow restorations showed Bravo scores at the end of 24 months. The restorations in both groups had Alfa ratings of 100% for the rest of the criteria evaluated. Conclusion: The nanohybrid and flowable resin composites showed similar clinical performances in the restoration of non-carious cervical lesions over 24 months.     

Effectiveness of a new one-step self-etch adhesive in the restoration of non-carious cervical lesions: 2-Year results of a randomized controlled practice-based study

Objectives

The purpose of this practice-based randomized controlled trial was to evaluate the effectiveness of a new one-step self-etch adhesive to restore non-carious cervical lesions following CONSORT guidelines and to test the hypothesis that this adhesive is equally effective with or without beforehand selective etching of enamel.

Methods

Twenty-eight patients each received two restorations randomly assigned to the control or the experimental group. In the control group, the adhesive (Bond Force, Tokuyama) was applied without beforehand enamel phosphoric-acid-etching, whereas the latter was applied first in the experimental group. The restorative composites used for all restorations were Estelite Flow Quick followed by Estelite Sigma (Tokuyama). The clinical effectiveness was assessed at baseline, 6 months, 1 year and 2 years in terms of retention, marginal staining, restoration staining, and post-operative sensitivity.

Results

One restoration loss occurred in the control group before the 6-month recall. At the two-year recall, only 2 secondary endpoints showed significant differences between groups: marginal staining at the enamel occurred more often in the control group (29% vs. 5%) (hierarchical linear regression: p = 0.011) and ‘minor marginal defects’ were significantly more frequent in the control group (29% vs. 0%) (hierarchical linear regression: p = 0.009).

Significance

Although in a practice setting, the effectiveness of this new adhesive was very good after 2 years of clinical service. More minor defects and restoration staining at the enamel margin were noticed when enamel had not been selectively acid-etched. Selective enamel acid-etching might enhance the adhesive properties of this new one-step self-etch adhesive.     

One-step self-etching adhesive polymerization: Influence of a self-curing activator

Objectives

The objectives of this work were to study the spatially resolved extent of photopolymerization and the final volumetric contraction of the self-etching adhesive Xeno IV (Dentsply/Caulk, Milford, DE, USA) in association with the self-curing agent Aurora (Dentsply/Caulk, Milford, DE, USA), using ¹H Stray-Field magnetic resonance imaging (¹H STRAFI-MRI).

Methods

One-dimensional ¹H STRAFI-MRI images (projections along an axis, profiles) were acquired from the adhesive with and without Aurora, before and after solvent removal. Specimens were observed after the irradiation period recommended by the manufacturers and new profiles were recorded. Extent of polymerization and volumetric contraction were obtained by subtracting the profile of the cured adhesive from the profile of the liquid; the profiles were previously normalized using an external reference signal and the highest magnetization intensity recorded from the cured adhesive, respectively. Data were obtained in the presence of oxygen. Solvent evaporation was measured by gravimetry.

Results

High volumetric contraction was observed for Xeno IV and Xeno IV and Aurora mixture mainly related to solvent evaporation. A drying period favourably influenced the extent of photopolymerization of Xeno IV, which did not increase in the presence of Aurora.

Conclusions

The incorporation of Aurora reduced the extent of polymerization of the one-step adhesive, probably due to the increase in the solvent content of the mixture. It may be that enhancing solvent evaporation is important in order to reach a higher extent of polymerization during the bonding procedure.     

Retention of a resin-modified glass ionomer adhesive in non-carious cervical lesions. A 6-year follow-up

OBJECTIVES: The purpose of this study was to evaluate the clinical retention of a new resin-modified glass ionomer cement based adhesive combined with a hybrid resin composite or a poly-acid modified resin composite in non-carious cervical lesions during a 6-year period. METHODS: The resin-modified glass ionomer adhesive (Fuji Bond LC), was placed in 73 cervical lesions, 36 with a universal hybrid resin composite (Tetric Ceram) and 37 with a poly-acid modified resin composite (Hytac). Fifty-one in lesions with sclerotic dentin and 22 in non-sclerotic ones. Of the sclerotic lesions 38 were slightly roughened with a diamond bur before conditioning. The restorations were evaluated with slightly modified USPHS criteria every six months during a 6-year period. RESULTS: All except six restorations were evaluated during the 6 years. Twelve (17.9%) were lost, four Tetric Ceram (11.8%) and eight Hytac (24.2%) (p<0.05). Four were found in non-sclerotic lesions (20.0%) and eight in sclerotic lesions (17.0%). The differences between the sclerotic and non-sclerotic and the roughened and non-roughened lesions were not significant. CONCLUSIONS: The resin-modified glass adhesive showed a superior clinical retention combined with the resin composite material, with an annual failure rate of 2%.     

Clinical comparison of a flowable composite and fissure sealant: A 24-month split-mouth,randomized, and controlled study

Objectives

The aim of this clinical study was to evaluate the retention rate and caries-prevention effect of a flowable composite compared to a conventional resin-based sealant in a young population over a 24-month period.

Methods

Thirty-four patients, ranging in age from 16 to 22 years, diagnosed with at least 2 non-cavitated pit-and-fissure caries in the first and second molars were selected for this randomized split-mouth design trial. A total of 220 sealants, were placed in 117 upper molars and 103 lower molars. The teeth were sealed with a flowable resin composite (Tetric Evo Flow) or a sealant material (Helioseal F). Each restoration was independently evaluated in terms of retention and the presence of caries at baseline and at 1, 6, 12, and 24 months. Data were analyzed using non-parametric Mann–Whitney U and Friedman 1-way ANOVA tests at p < 0.05.

Results

Tetric Evo Flow showed complete retention with 100%, 95.5%, 93.8%, and 88.5% at 1, 6, 12, and 24-month evaluations, respectively, while Helioseal F retention rates were 98.1%, 95.5%, 94.8%, and 85.4%, respectively, for the same evaluation periods. At the 24-month recall, 4 (4.2%) total losses were observed in subjects treated with Tetric Evo Flow and 2 total losses (2.1%) for Helioseal F, respectively. No significant differences were observed between the materials in retention rates or caries incidence for each evaluation period (p > 0.05).

Conclusion

Placement of flowable composite as fissure sealants in the younger population seems to be as effective as conventional fluoride containing fissure sealants for the prevention of fissure caries.

Clinical relevance

The use of a flowable composite as a fissure sealant material, in conjunction with a total-etch, single bottle adhesive, yielded better retention than did the conventional fluoride containing resin-based fissure sealant over a 24-month period in young patients.     

Bond strengths, degree of conversion of the cement and molecular structure of the adhesive-dentine joint in fibre post restorations

Objectives

Because fibre post restorations are influenced by multiple factors such as the types of bonding materials, the dentine region and the time under moist exposure, this study sought to determine the bond strength of endodontic restorations and its relation to the degree of conversion of the cement layer and the molecular structure of the dentine-bonded joints.

Methods

The performance of 2 etch-and-rinse (All-Bond 2 and One-Step Plus) and 2 self-etch (Clearfil SE Bond and Xeno III) adhesives at post spaces regions, after 7 d or 4 m, was evaluated. FRC Postec Plus posts were cemented to the root canal with a dual-cure resin cement (Duo-Link). Transverse sections of the tooth were subjected to push-out testing, to degree-of-conversion measurements and to hybrid layer evaluation through μ-Raman spectroscopy.

Results

Coronal bonding was higher than cervical and middle bonding. The hybrid layer was thicker for the etch-and-rinse systems, with thicknesses decreasing towards the middle region. The degree of conversion measured for the 3-step etch-and-rinse group after 4 m was significantly higher than that for the self-etching groups.

Conclusions

Although not totally stable at the adhesive–dentine interface, the 3-step etch-and-rinse adhesive in the coronal dentine provided the best bond strength, degree of conversion of the cement and hybrid layer thickness in post restorations, in both short- and long-term analyses.     

One-year clinical evaluation of tooth-colored materials in non-carious cervical lesions

The purpose of this study was to assess the clinical performance of bonded composite (Excite/Tetric Ceram - Vivadent) versus a resin-modified glass ionomer cement (Vitremer - 3M) for restoring non-carious cervical lesions. A total of 70 restorations (thirty-five per material) were placed in 30 patients, 18-50 aged, by one operator. Rubber dam was employed in all cases, lesions were pumiced, enamel margins were not beveled, and no mechanical retention was placed. The restorations were directly assessed by two independent evaluators using modified-USPHS criteria for six clinical categories. The ratings for clinical acceptability restorations (alfa plus bravo) were as follows (Tetric Ceram/Vitremer): retention (86%/100%), marginal integrity (100%/100%), marginal discoloration (100%/100%), wear (97%/100%), postoperative sensitivity (100%/100%) and recurrent caries (100%/100%). Statistical analysis was completed with Fisher's exact or Pearson Chi-square tests at a significance level of 5% (P<0.05). Results showed that almost all restorations were clinically satisfactory with no significant differences between materials groups. Five restorations of Excite/Tetric Ceram failed. No restorations of Vitremer have yet failed.