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Aims: To compare the effects of repeated use of two one-bottle adhesives with that of two all- in- one adhesives (with acetone solvent) on bond strength to dentin. Materials and Methods: A flat dentin surface was prepared on 120 bovine incisors using 600- grit abrasive pape. The teeth were randomly assigned into 12 equal groups. The four adhesive systems [Prime and Bond NT (P&B NT), One-Step Plus (OS), iBond (iB), and G-Bond (GB)] were used at baseline, after the lid of the container had been opened 30 times, and after it had been opened 60 times. Before each use of the adhesives, the lids of the containers were left open for 1 min. The resin composites were applied on the dentin in a cylindrical split mold. After thermocycling, shear bond strength test was performed with a universal testing machine at 1 mm/min. We used Kruskal-Wallis and Dunn tests for statistical analysis. Results: There was no statistically significant difference among bond strength (MPa) of the groups of P&B NT (31.9 ± 4.6, 31.8 ± 6.5, 26.1 ± 6.7) and OS (33.2 ± 5.1, 30.9 ± 7, 29.3 ± 5.9), respectively (P > 0.05). The mean of the bond strength of iB and GB after 60 times (15.3 ± 4.1 and 12.2 ± 3.9, respectively) was significantly lower than that of iB and GB at baseline (23.5 ± 4.8 and 22.2 ± 4.5, respectively) (P < 0.05). Conclusions: Repeated use (60 times) of the all-in-one adhesive led to a decline in the dentin bond strength. To avoid this problem it would be advisable to have containers with smaller amounts of adhesive or perhaps those with only a singe dose.

Background: The main disadvantage of silver diamine fluoride (SDF) is its persistent dark coloring. The aim of this study was to cover this discoloration on affected primary tooth dentin with different materials and subsequently measure their shear bond strength (SBS). Materials and Methods: In this in vitro study total of 60 primary teeth were demineralized and randomly divided into five groups (n = 12). The tooth surfaces were treated with 38% SDF, and restorative cylinders were built on the dentin as follows: (1) phosphoric acid etching + GLUMA Universal Adhesive (GUA; etch-and-rinse mode) + composite resin (CR); (2) GUA (self-etch mode) + CR; (3) resin-modified glass ionomer (RMGI; Fuji II); (4) Surefil One (self-adhesive CR); and (5) TheraCem (self-adhesive resin cement) + CR. After restoration, the specimens were tested for SBS. Failure mode was determined by digital analysis and scanning electron microscopy. Data were analyzed by one-way analysis of variance and Tukey's honest significant difference post hoc test. P <0.05 indicated statistical significance. Results: Group 1 had significantly higher mean SBS (P < 0.05) compared to Groups 2-5, while Group 5 had the least SBS (P < 0.001). Mean SBS differences between Groups 2 and 3 were not significant (P = 0.328). Group 4 had lower mean SBS than Groups 1 (P < 0.001) and 2 (P = 0.17). Most groups showed adhesive failure. Conclusion: CR associated with the universal adhesive in etch-and-rinse mode had much higher SBS than the other groups; therefore, we recommend it to cover the dark discoloration generated by SDF. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to review the in vitro literature on shear bond strength (SBS) and microleakage of pit and fissure sealant materials in contaminated (water, human, or artificial saliva) and non-contaminated conditions. Methods: PubMed®, Web of Science™, Scopus®, Embase™, and Cochrane Library databases were used as data sources. Of the 974 studies identified, 56 were considered eligible for full-text screening and 32 were selected for data extraction. Results: The meta-analysis demonstrated that contaminated conditions decreased the SBS of the sealants by 4.33 MPa. In the contaminated subgroup analysis, both unfilled (Clinpro™, 3M™) and filled (FluroShield®, Dentsply) resin-based sealants achieved a similar SBS (P=0.82). Regarding the outcome measurements, extensive methodological heterogeneity was found among the studies for SBS measurements (I 2 equals greater than or equal to 84 percent; P<0.001), whereas homogeneity was found for microleakage (I 2 equals 84 percent; P=0.85). When evaluating resin-based sealants, the level of microleakage in the contaminated and noncontaminated groups was not significantly different (P=0.1). Conclusion: Surface contamination decreases the bond strength between contaminated enamel and both unfilled and filled resin-based sealants, which affects the clinical effectiveness of sealants. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Management of dental caries during early stages is considered a clinical problem in young children. OBJECTIVES: The current in-vitro study assessed the influence of four home oral care products on re-mineralization of early caries lesions using enamel micro-hardness (EMH) test and morphological changes with scanning electron microscopy (SEM). MATERIAL AND METHODS: Sixty primary canine teeth were selected and randomly divided into 5 groups (n = 12 in each group). Samples were de-mineralized, and toothpaste slurries were prepared to treat de-mineralized enamel with a pH-cycling model. The groups were divided as follows: Group 1. Control (no intervention); Group 2. Fluoridated toothpaste; Group 3. Tooth mousse containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP); Group 4. Toothpaste containing bio-active glass and fluoride; Group 5. Tooth cream containing nano-hydroxyapatite, fluoride, and xylitol. EMH was evaluated in fifty specimens (each group, n = 10) at three times: before and after de-mineralization, and after 28 days of pH-cycling and treatment. Two samples from each group were observed with SEM. Data were analyzed with multiple-sample repeated measures ANOVA and Tukey's HSD post-hoc tests (p < 0.05). RESULTS: There was a significant difference in EMH between mean baseline values and de-mineralized enamel (p < 0.001). Re-mineralization significantly increased EMH in all treatment groups (p < 0.001). In group 5, the percent of EMH recovery was significantly greater than in other groups (p < 0.001). There were significant differences among the other three treatment groups (all p < 0.001). SEM images showed minerals deposited on the dissolved prismatic enamel in all groups. CONCLUSIONS: The nano-hydroxyapatite-based tooth cream was the most effective home oral care product for re-mineralization of primary tooth enamel. [ABSTRACT FROM AUTHOR]

This study investigated the effect of dentin-desensitizing treatment with a casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) paste on shear bond strength (SBS) of two types of self-adhering (SA) restorative materials: resin-modified glass-ionomer (Fuji II LC, GC) and self-adhering flowable composite resin (Vertise Flow, Kerr). Flat and smear layer–free dentin surfaces from 48 extracted molars were prepared and divided into four groups (n = 12 per group) according to Fuji II LC or Vertise Flow and CPP–ACP pretreatment or not. After SBS testing, data were statistically analyzed. The adhesive interfaces were examined by scanning electron microscopy. SBS was significantly affected by CPP–ACP treatment (P < .001) and SA material (P < .05). The interaction of the two factors was not significant. The results suggested that the CPP–ACP pretreatment of the exposed dentin could have a beneficial effect on bonding ability and interfacial integrity of both SA materials so that intimately adapted interfaces were observed in CPP–ACP groups. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the remineralization of enamel caries lesions using the self‐assembling peptide P11‐4 associated with different materials. Artificial early enamel lesions were prepared on 154 primary teeth. The samples were randomly divided into eight groups: (1) control, (2) P11‐4, (3) fluoridate toothpaste (FT), (4) P11‐4 + FT, (5) casein phosphopeptide–amorphous calcium phosphate (CPP–ACP), (6) P11‐4 + CPP–ACP, (7) fluoridate bioactive glass toothpaste (BT), and (8) P11‐4 + BT. The surface enamel microhardness (EMH) and energy‐dispersive X‐ray spectroscopy (EDS) of the teeth were then measured at the baseline, after demineralization, and after 28 days of remineralization. The enamel surfaces were assessed by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The data were analyzed with one‐way analysis of variance (ANOVA) (p <.05). EMH after demineralization was significantly lower than the baseline value (p <.001). The interventions led to an enhanced percentage of EMH recovery (%REMH), which was higher in Groups 6 and 7. There was no significant difference between Groups 3 and 4. Groups 1 and 2 had the lowest %REMH. The mean calcium/phosphate weight percentage ratio of P11‐4 was significantly lower than the others (p <.001). The FESEM and AFM images revealed mineral deposition on the eroded enamel and reductions in surface roughness in Groups 5 and 7. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate microleakage from an antibacterial adhesive and bonding agent added to the fissure sealant on intact enamel. Materials and Methods: One hundred twenty sound third mandibular molars were randomly divided into 6 groups of 20 teeth each. Occlusal pits and fissures were sealed with unfilled sealant material (Clinpro, 3M) after pretreatment with 1. phosphoric acid etching (control); 2. acid etching + Adper Single Bond 2 (SB, 3M); 3. chlorhexidine digluconate (CHX, Ultradent) + acid etching; 4. CHX + acid etching + SB; 5. acid etching + Clearfil Protect Bond (CPB, Kuraray) 6. CPB alone. After 6-month water storage and thermocycling, the specimens were placed in 0.5% fuschin, sectioned and evaluated under a digital microscope. The data were compared between groups with Kruskal-Wallis and Mann-Whitney tests. Results: Differences between groups were statistically significant at P < 0.05. Acid etching alone and with SB showed the lowest microleakage, followed by acid etching + CPB. Chlorhexidine with and without bonding agent showed the greatest microleakage. Conclusion: Conventional acid etching alone or with a one-bottle adhesive were the two most effective methods of reducing microleakage from fissures. Acid etching together with a self-etching adhesive showed better results than self-etching alone. Appling CHX increased microleakage in sealed teeth. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical performance of polyethylene fiber for anterior primary teeth restorations in children after 2.5 years, according to modified Ryge criteria. Materials and Methods: Fifty-five maxillary incisors with extensive caries in 24 Iranian patients (mean age 4.2 years) were restored. All teeth were treated endodontically. First, 4-mm layer of paste at the entrance of canal was removed, and a thin base layer of polycarboxylate cement was placed at the bottom of the prepared canal. All tooth surfaces were etched, rinsed and dried, and the dentin adhesive Single Bond (3M ESPE, St Paul, MN, USA) was applied. The teeth received intracanal fiber-reinforced resin (Ribbond Triaxial, Seattle, WA, USA) fixed with a flowable composite and the crowns were reconstructed with microhybrid composite resin (Z250, 3M). All restorations were evaluated every 6 months for 30 months by 2 independent evaluators. Statistical analysis was done with McNemar's test. Results: The surface textures for most of the restorations were judged as excellent. There was no evidence of significant changes in marginal integrity. Most restored incisors (81%) received an Alpha rating for retention. The baseline and recall retention scores differed significantly (p=0.002). Conclusion: Polyethylene fiber posts associated with extensive composite restoration showed excellent clinical performance after 2.5 years in primary anterior teeth after pulp therapy. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated sealants placed on permanent molars in first-grade students in Shiraz primary schools during 2008 under a school oral health programme.Materials and Methods: A total of 420 sealed first permanent molar teeth in 179 students (mean age 8 years, 6 months) were evaluated for fissure sealant retention, occlusal caries status and Feigal criteria. All teeth were examined 1.5 years after application. The fissure sealants (Conceal F, SDI) were placed on occlusal surfaces after traditional acid etching. Statistical analysis was done with the chi-square test (P < 0.05).Results: 57.5% of the seals were completely retained, 29.6% partially lost and 12.9% completely lost. There were no signs of carious lesions in 77.1% of the teeth. According to the Feigal criteria, success rates based on marginal integrity, marginal discolouration and anatomical form were 98.2%, 95.5% and 58.6%, respectively. The overall success rate with all three criteria was 54.14%. There were no significant relationships between the results and patient gender or tooth position in the arch.Conclusion: Although fissure sealants are an effective method for preventing tooth caries, the results of this study indicate that public oral health programmes need to be implemented more carefully and that follow-up programmes are advisable. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to evaluate the adhesion of Scotchbond Universal Adhesive to primary tooth dentin by measuring shear bond strength (SBS) and observing morphological changes with scanning electron microscopy (SEM). Materials and Methods: In this in vitro study, a total of 60 primary canine teeth were randomly divided into 5 groups (n = 12). The study groups were (1) Phosphoric acid etching + Adper Single Bond 2 (control), (2) phosphoric acid etching + Scotchbond Universal (etch-and-rinse), (3) Scotchbond Universal (self-etch), (4) phosphoric acid etching + Scotchbond Universal + resin, and (5) Scotchbond Universal + resin. Composite cylinders were built on the tooth surface, and 10 samples in each group were selected for SBS testing and identification of the failure modes. Two samples from each group were observed by SEM. One-way ANOVA and Tukey honestly significant difference post hoc test were used for data analysis P value < 0.05 was considered statistically significant. Results: The results showed that SBS in Group 1 was significantly lower than in Groups 2, 3, and 4 (all P < 0.001). There was no significant difference between Groups 2 and 3 (P = 0.98), or between Groups 3 and 4 (P = 0.97). There was no significant difference between Groups 2 and 4 (P = 0.999) or between Groups 1 and 5 (P = 0.156). Mixed and cohesive failures were more frequent in Groups 2, 3 and 4. SEM observations showed that applying phosphoric acid to the dentin before Scotchbond Universal adhesive resulted in more open dentinal tubules and more resin tag impregnation. Conclusion: There was no significant difference in SBS between Scotchbond Universal Adhesive in etch-and-rinse and self-etching modes. The SBS of Scotchbond Universal Adhesive in etch-and-rinse mode was greater than Adper Single Bond 2. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to investigate the sealing ability of three different resin cements for the luting of a porcelain laminate veneer (PLV) to the enamel and dentin of fluorosed teeth. Materials and method: Thirty incisors with moderate fluorosis according to the Thylstrup-Fejerskov Index (TFI = 4 to 6) received a veneer preparation with dentin margins at the gingival third. The IPS Empress (Ivoclar Vivadent) veneers were luted to the teeth of three groups (n = 10) using three different resin cements: Group 1: Excite DSC/Variolink II -- etch-and-rinse (E&R); Group 2: ED Primer II/Clearfil Esthetic -- self-etch (SE); Group 3: RelyX Unicem -- self-adhesive (SA). After 24 h of water storage and thermocycling, marginal microleakage was evaluated on three slices from each tooth using the dye penetration technique under a digital microscope. Results: Data (microleakage percentage over the entire preparation length) were analyzed using the Kruskal-Wallis and Mann-Whitney tests (P < 0.05). Mean microleakage percentage was 0.8% to 18% at the enamel and dentin margins, respectively. On the enamel, Group 1 (E&R) exhibited significantly less microleakage compared to Groups 2 (SE; P = 0.03), and 3 (SA; P = 0.005). On the dentin, microleakage in Group 3 (SA) was significantly less than that in Groups 1 (E&R; P = 0.001), and 2 (SE; P = 0.03). The difference between the latter two groups was significant, with Group 1 (E&R) exhibiting the greatest microleakage. Conclusion: The best enamel and dentin sealing of the cemented veneers was obtained with the E&R and SA luting agents, respectively. [ABSTRACT FROM AUTHOR]

Background: Obtaining optimal marginal adaption with prefabricated stainless steel crowns (SSCs) is difficult, especially after removing dental caries or defects in cervical areas. This situation requires the use of an SSC after tooth reconstruction. This study evaluated microleakage and material loss with five restorative materials at SSC margins. Materials and Methods: One hundred and twenty primary molar teeth were randomly divided into six groups (n = 20). Class V cavities were prepared on the buccal surfaces of the teeth in groups 1-5. Cavities were restored with amalgam, resin-based composite, glass ionomer (GI), zinc phosphate, or reinforced zinc oxide eugenol (Zonalin). Group 6 without cavity preparation was used as a control. Restorations with SSCs were prepared according to standard methods. Then, SSCs were fitted so that the crown margins overlaid the restorative materials and cemented with GI. After thermocycling, the specimens were placed in 0.5% fuchsin and sectioned. The proportions of mircoleakage and material loss were evaluated with a digital microscope. Statistical analysis was performed with Kruskal--Wallis and Mann--Whitney tests. Results: The groups differed significantly (P < 0.001). Amalgam and GI showed the least microleakage. Amalgam restorations had significantly less microleakage than the other materials (P < 0.05). Microleakage was greatest with resin-based composite, followed by Zonalin. Material loss was greater in samples restored with Zonalin and zinc phosphate. Conclusion: When SSC margins overlaid the restoration materials, cavity restoration with amalgam or GI before SSC placement led to less microleakage and material loss. Regarding microleakage and material loss, resin-based composite, zinc phosphate, and Zonalin were not suitable options. [ABSTRACT FROM AUTHOR]