Hybrid layer thickness and resin tag length of a self-etching adhesive bonded to sound dentin

Objectives: the purpose of this study is to employ optical microscopy to measure the thickness of the hybrid layer and the penetration (tags) of an aggressive self-etching adhesive system into sound dentin. Methods: occtusat cavities were prepared in 40 extracted human posterior teeth. The prepared teeth were randomly assigned to four experimental groups with 10 specimens each. The self-etching adhesive system Adper Prompt L-Pop was applied to the dentin surface as follows: Group 1: cavosurface enamel was etched for 60 s and dentin for 20 s with 35% phosphoric acid get, immediately followed by application of the self -etching adhesive with a brush to the entire cavity for 15 s; Groups 2, 3, and 4: no pre-etching was performed, and the self -etching adhesive was applied to both enamel and dentin for 15, 30 and 45 s, respectively. After curing, the cavities were fitted with composite resin Fittek Z250. Afterwards, the teeth were decalcified and the restorations were carefully removed for later embedding in paraffin. The specimens were serially sectioned at 6 mu m of thickness and sequentially mounted in glass slides. These sections were stained with Brown and Brenn staining for posterior analysis and measurement of the hybrid layer and resin tags on a tight microscope with a micrometric ocular 40/075. The results were submitted to analysis of variance at the 5% level. Results: whenever there was significance, the Tukey test was applied at the 5% level. The specimens receiving application of acid etching before the selfetching. adhesive displayed a larger thickness of the hybrid layer; on the other hand, specimens receiving only application of the self -etching adhesive on dentin for 15, 30 and 45 s exhibited similar thickness of the hybrid layer. As regards the resin tags, no statistically significant differences could be found between the study groups. Conclusions: it could be concluded that the increase in the time of application of the self-etching adhesive Adper Prompt L-Pop did not significantly influence the formation and thickness of hybrid layer, as well as its penetration into the sound dentin surface. (c) 2005 Elsevier Ltd. All rights reserved.33867568

Considerations about enamel microabrasion after 18 years

Purpose: To review of the current status of enamel microabrasion method and its results 18 years after the development and application of this method. Methods: A technique performing enamel microabrasion with hydrochloric acid mixed with pumice and other techniques employing a commercially available compound of hydrochloric acid and fine-grit silicon carbide particles in a water-soluble paste have been described. Much has been learned about the application of this esthetic technique, long-term treatment results and microscopic changes to the enamel surface that has significant clinical implications. The latest treatment protocol is presented and photographic case histories document the treatment results. Clinical observations made over 18 years are discussed. Results: According to our findings, the dental enamel microabrasion technique is a highly satisfactory, safe and effective procedure.202677

Microleakage of adhesively bonded cervical amalgam restorations

Purpose: To evaluate dye penetration in adhesively bonded cervical amalgam restorations. Materials and Methods: The specimens were randomly divided into four groups and the adhesives Prime & Bond 2. 1, Prime & Bond 2.1 Dual Cure, Scotchbond Multi Purpose Plus and Amalgambond Plus were tested. After being restored and polished, the teeth were thermocycled 1,000 times at temperatures varying between 5degreesC +/- 2degreesC and 55degreesC +/- 2degreesC. Statistical analysis was carried out using the Kruskal-Wallis test and multiple comparisons. Results: Scotchbond Multi-Purpose Plus demonstrated lower levels of microleakage in enamel and dentin. The dual adhesives were more effective than the "one bottle" adhesive.15317317

In Vitro Evaluation of Surface Roughness and Microhardness of Restorative Materials Submitted to Erosive Challenges

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The aim of this study was to evaluate the effect of different acidic solutions on the microhardness and surface roughness of restorative materials. The 120 specimens of restorative materials (Fuji II LC, Vitremer, Supreme XT, and Supreme XT + Biscover LV) were randomly divided into three groups according to the immersion media: hydrochloric acid, soft drink, or distilled water. Over a period of five weeks, the groups were immersed in the solutions, which were changed weekly. Data were tested using analysis of variance and the Fisher protected least significant difference test (p < 0.05). The results showed that the glass ionomer materials showed the highest surface roughness values (Fuji II LC: 0.111 +/- 0.014 mu m before and 0.139 +/- 0.016 mu m after immersion; Vitremer: 0.177 +/- 0.012 mu m before and 0.084 +/- 0.012 mu m after immersion), whereas the lowest values were found for the resin sealed with Biscover LV before (0.047 +/- 0.011 mu m) and after exposure in distilled water (0.043 +/- 0.007 mu m), soft drink (0.040 +/- 0.005 mu m), and hydrochloric acid (0.045 +/- 0.005 mu m). The Supreme XT showed the highest microhardness values before (44.96 +/- 2.51 KHN) and after the aging process (41.26 +/- 1.22 KHN in water, 35.96 +/- 0.81 KHN in soft drink, and 34.74 +/- 0.97 KHN in HCl), with significant differences from the other materials (p < 0.0001). The lowest microhardness values were found for glass ionomer materials. The solutions used in this study decreased the microhardness of all studied materials, whereas the sealed surface suffered minor changes in microhardness and surface roughness after exposure to acidic solutions.364397402Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2008/54115-5

Microleakage of adhesively bonded cervical amalgam restorations

Purpose: To evaluate dye penetration in adhesively bonded cervical amalgam restorations. Materials and Methods: the specimens were randomly divided into four groups and the adhesives Prime & Bond 2. 1, Prime & Bond 2.1 Dual Cure, Scotchbond Multi Purpose Plus and Amalgambond Plus were tested. After being restored and polished, the teeth were thermocycled 1,000 times at temperatures varying between 5degreesC +/- 2degreesC and 55degreesC +/- 2degreesC. Statistical analysis was carried out using the Kruskal-Wallis test and multiple comparisons. Results: Scotchbond Multi-Purpose Plus demonstrated lower levels of microleakage in enamel and dentin. The dual adhesives were more effective than the one bottle adhesive

Hybrid layer thickness and resin tag length of a self-etching adhesive bonded to sound dentin

Objectives: the purpose of this study is to employ optical microscopy to measure the thickness of the hybrid layer and the penetration (tags) of an aggressive self-etching adhesive system into sound dentin.Methods: occtusat cavities were prepared in 40 extracted human posterior teeth. The prepared teeth were randomly assigned to four experimental groups with 10 specimens each. The self-etching adhesive system Adper Prompt L-Pop was applied to the dentin surface as follows: Group 1: cavosurface enamel was etched for 60 s and dentin for 20 s with 35% phosphoric acid get, immediately followed by application of the self -etching adhesive with a brush to the entire cavity for 15 s; Groups 2, 3, and 4: no pre-etching was performed, and the self -etching adhesive was applied to both enamel and dentin for 15, 30 and 45 s, respectively. After curing, the cavities were fitted with composite resin Fittek Z250. Afterwards, the teeth were decalcified and the restorations were carefully removed for later embedding in paraffin. The specimens were serially sectioned at 6 mu m of thickness and sequentially mounted in glass slides. These sections were stained with Brown and Brenn staining for posterior analysis and measurement of the hybrid layer and resin tags on a tight microscope with a micrometric ocular 40/075. The results were submitted to analysis of variance at the 5% level.Results: whenever there was significance, the Tukey test was applied at the 5% level. The specimens receiving application of acid etching before the selfetching. adhesive displayed a larger thickness of the hybrid layer; on the other hand, specimens receiving only application of the self -etching adhesive on dentin for 15, 30 and 45 s exhibited similar thickness of the hybrid layer. As regards the resin tags, no statistically significant differences could be found between the study groups.Conclusions: it could be concluded that the increase in the time of application of the self-etching adhesive Adper Prompt L-Pop did not significantly influence the formation and thickness of hybrid layer, as well as its penetration into the sound dentin surface. (c) 2005 Elsevier Ltd. All rights reserved

Clinical assessment of postoperative sensitivity in posterior composite restorations

This incidence of postoperative sensitivity was evaluated in resin-based posterior restorations. Two hundred and ninety-two direct restorations were evaluated in premolars and molars. A total of 143 Class I and 149 Class 11 restorations (MO/OD and MOD) were placed in patients ranging in age from 30 to 50 years. After the cavity preparations were completed, a rubber dam was placed, and the preparations were restored using a total-etch system (Prime & Bond NT) and a resin-based restorative material (TPH Spectrum). The patients were contacted after 24 hours and 7, 30 and 90 days postoperatively and questioned regarding the presence of sensitivity and the stimuli that triggered that sensitivity. The Chi-square and Fisher's Exact Test were used for statistical analysis. Evaluation at 24 hours after restorative treatment revealed statistically significant differences among the types of cavity preparations restored and the occurrence of postoperative sensitivity (p=0.0003), with a higher frequency of sensitivity in Class H MOD restorations (26%), followed by Class II MO/DO (15%) and Class I restorations (5%). At 7, 30 and 90 days after restorative treatment, there was a decrease in the occurrence of sensitivity for all groups. The percentage of sensitivity among the groups was not significantly different. This study shows that the occurrence of sensitivity is correlated with the complexity of the restoration.32542142