Characterization and Anti-Caries Effect of an Experimental Adhesive Containing Natural Antimicrobial Agents.

PURPOSE: To characterize experimental adhesives containing natural antimicrobial agents (proanthocyanidins, apigenin, tt-farnesol) in the primer and to evaluate their anti-caries effect. MATERIALS AND METHODS: Natural agents were incorporated in the primer of an experimental adhesive: 4.5% proanthocyanidins (PA), 1 mM apigenin (API), 1 mM apigenin + 5 mM tt-farnesol (API + FAR), and primer without antimicrobial agent (control). Microtensile bond strength (µTBS) to dentin and nanoleakage were measured immediately (n = 7) and after 1 year of storage (n = 7). Water sorption (WS), solubility (SO), and degree of conversion (DC%) of the adhesives were measured. The hardness loss of enamel (n = 6) and dentin (n = 6) at the restorative margin was evaluated after biofilm formation. RESULTS: DC%, nanoleakage, and immediate µTBS were similar for all groups. After 1 year, API + FAR showed higher nanoleakage and lower µTBS than the other groups, which were similar. WS and SO of API + FAR were lower than in the other groups. PA, API, and API + FAR presented less hardness loss than did the control group. At enamel, PA and API presented less hardness loss than the control and API + FAR groups at distances 50 µm and 100 µm; the hardness loss of enamel was similar for all groups 150 µm from the margin. CONCLUSION: The addition of proanthocyanidins and apigenin to the adhesives decreased the hardness loss of dentin and enamel submitted to biofilm formation, without jeopardizing the physical properties of the adhesives. The combination of apigenin + tt-farnesol decreased the hardness loss of dentin but not of enamel, and decreased the µTBS after 1 year of storage.

Factors Associated with Noncarious Cervical Lesions in Different Age Ranges: A Cross-sectional Study.

OBJECTIVES: Understanding the possible risk factors of noncarious cervical lesion (NCCL) is important for prevention and clinical management of the condition. The aim of this study was to investigate the factors associated with the prevalence of NCCL among adolescents, adults, and elderly people. MATERIALS AND METHODS: A cross-sectional study involving 501 participants aged 15 years or older was conducted. Participants were examined to assess the number of natural teeth and the prevalence and severity of NCCL by calibrated examiners. Data on age, gender, harmful toothbrushing habits, and acidogenic diet were collected through individual interviews. Multivariate Poisson's regression models were used to evaluate the association between the independent variables and the prevalence of NCCL according to the three age groups: 15 to 39, 40 to 64, and 65 years or older. RESULTS : The prevalence of NCCL among participants was 62.5% (95% confidence interval: 58.2-66.7). Among 15- to 39-year-old participants, the mean of NCCL was higher in males, those with lower number of teeth and acidogenic diet intake. Males aged 40 to 64 years and those with harmful brushing habits were more likely to present higher mean of NCCL. Elderly people with harmful toothbrushing habits had a greater mean of NCCL. CONCLUSION: Demographic (age and gender), clinical (number of teeth), and behavioral characteristics (harmful brushing habits and acidogenic diet) were meaningful factors associated with NCCL severity. The above-mentioned relationships varied between age groups.

Resin-dentin bond stability of etch-and-rinse adhesive systems with different concentrations of MMP inhibitor GM1489.

Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher µTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.

Characterization and Antibacterial Effect of an Experimental Adhesive Containing Different Concentrations of Proanthocyanidin.

PURPOSE: To evaluate the degree of conversion (DC%), water sorption (Sp), solubility (Sl), dentin bond strength (µTBS) (immediate and after 12 months of storage), and the antibacterial effect of an experimental adhesive containing different concentrations (%) of proanthocyanidin (PA): 0, 1%, 2%, 4.5%, and 6% (PA0, PA1%, PA2%, PA4.5% and PA6%, respectively). MATERIALS AND METHODS: DC% was measured by FT-IR and the Sp and Sl were determined based on the ISO 4049 specification. For µTBS, resin composite buildups were constructed incrementally and specimens (n = 8) were sectioned to obtain sticks (1 mm2). The µTBS was evaluated after 24 h and 12 months of water storage at 37°C. The failure mode was analyzed. The antibacterial effects were evaluated by analyzing the bacterial growth (S. mutans) (n = 5) and antibiofilm activity (n = 5) of the adhesives by spectrophotometry. RESULTS: The incorporation of PA did not affect the Sp, Sl, or DC%. Immediate µTBS was similar for all groups. After 12 months, PA4.5% presented significantly higher µTBS than PA0, while the other groups did not differ from PA0 and PA4.5%. Groups PA0 and PA1% underwent significant reduction in µTBS. In the experimental groups PA2%, PA4.5% and PA6%, µTBS was maintained after storage. All groups showed antibacterial activity. CONCLUSION: Incorporation of 2%, 4.5%, and 6% PA maintained the dentin µTBS after 12-month storage, without affecting the Sp, Sl, or DC% of experimental adhesives. PA4.5% presented higher µTBS values than PA0 after 12 months. The adhesive presented antibacterial effect irrespective of PA concentration.

Resin-dentin bond stability of etch-and-rinse adhesive systems with different concentrations of MMP inhibitor GM1489

Abstract Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher μTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.

Bond stability of conventional adhesive system with MMP inhibitors to superficial and deep dentin.

PURPOSE: To evaluate the microshear bond strength (µSBS) to deep (DD) or superficial (SD) dentin (µSBS) overtime, nanoleakage (AG%), degree of conversion (DC%), water sorption (WSp), and solubility (WSl) of an adhesive system [Adper Single Bond 2(ASB)] containing matrix metalloproteinases (MMP) inhibitors [GM1489 (ASB-GM), Batimastat (ASB-BAT), or Chlorhexidine diacetate (ASB-CHX)]. ASB without inhibitor was used as control (CONTROL). MATERIALS AND METHODS: WSp and WSL were calculated based on ISO4049. DC% was analyzed using FT-IR spectroscopy. Dentin discs were used for µSBS evaluation. For AG%, resin-dentin beams were analyzed under scanning electronic microscopy. Data were analyzed using three-way ANOVA (AG% and µSBS) or ANOVA (DC%, WSp, WSl) and Tukey's HSD test. RESULTS: ASB-CHX presented the lowest DC%, lowest WSp, and highest WSl. ASB-GM reached the highest immediate µSBS in SD, only different from ASB-CHX. In DD, ASB-BAT and ASB-GM had the highest µSBS, statistically different from ASB-CHX. After twelve months, ASB-GM and ASB-BAT presented higher µSBS in SD when compared to CONTROL and ASB-CHX. In DD, ASB-GM reached the highest value, which was statistically different from CONTROL and ASB-CHX. CONTROL at both dentin depths and ASB-CHX at DD did not maintain bond stability. In SD after 12 months, ASB-BAT and ASB-GM decreased AG%. In DD, only ASB-GM reduced AG%. CONCLUSION: The ASB containing Batimastat and GM1489 maintained resin-dentin bond stability after 12 months for both dentin depths, without jeopardizing WSp, WSl, or DC% of the adhesive system. The ASB-GM presented greater µSBS after 12 months when compared with ASB. CLINICAL SIGNIFICANCE: Batimastat and GM1489 could be suitable for inclusion as an MMP-inhibitor into Single Bond to improve the bond stability to superficial and deep dentin, without jeopardize the physic-mechanical proprieties.

Sodium fluoride and casein phosphopeptide-amorphous calcium phosphate cream plus sodium fluoride efficacy in preventing enamel erosion in a simulated oral environment study model.

AIM: The aim of this study was to evaluate the effectiveness of dentifrices containing high concentrations of sodium fluoride (NaF) and casein phosphopeptide-amorphous calcium phosphate cream plus fluoride (CPP-ACPF) in prevention of the erosion in a simulated oral environment study model. SUBJECTS AND METHODS: Fifteen flat human enamel specimens were polished and half of the surfaces were protected with adhesive tape. Initial Knoop microhardness (KHN) and surface roughness (SR) were measured, and specimens were assigned to four groups: Control (placebo toothpaste - G1); CPP-ACPF (G2), NaF 1450 ppm (G3), and NaF 5000 ppm (G4). Enamel surfaces were brushed 3 times daily in association with demineralization-remineralization cycles (5s in cola drink + 5s in artificial saliva/10 cycles/twice daily) and the specimens were maintained in a salivary flow simulator apparatus. After 14 days, KHN and SR were measured again, and the enamel surfaces were analyzed by scanning electronic microscopy (SEM). STATISTICAL ANALYSIS USED: Data were analyzed using the two-way ANOVA and Student-Newman-Keuls multiple range test (α =0.05). RESULTS: All the tested groups presented a decrease in KHN after 14 days (P < 0.05). There was no statistical significance among materials tested. Significant increase in SR was observed for all groups. SEM analysis showed morphological alterations with honeycomb structures in enamel surfaces in the four experimental groups. CONCLUSIONS: It was concluded that tooth brushing with dentifrices with high concentration of NaF and CPP-ACPF cream was not able to prevent enamel erosion in simulated oral environment.