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The purpose of this study is to compare the effect of a demineralization model on the microhardness, surface roughness, and topography of giomers.Seventy‐two discs of six different dental materials in three different presentations (pit and fissure sealant (PFS), flowable and restorative materials) were divided into six groups (n = 12 p/g). Three experimental groups (giomers) consisted of BeautiSealant, Beautifil Flow Plus, and Beautifil II, and three control groups (resin‐based materials) were formed using ClinproTM, FiltekTM Z350 XT Flow, and Filtek™ Bulk Fill materials. Vickers microhardness, surface roughness, and topographic analysis with atomic force microscopy were measured at the beginning (0) after four (1) and 7 days (2) of immersion in a demineralizing model. Statistical analysis was performed using One‐way and Repeated Measures ANOVA and Pearson's correlation coefficient (p ≤.05). The microhardness values showed significant variations, except for the G_RM group. All the groups presented significant increases in roughness through the experiment stages, except for RB_PFS in the Ra parameter. The topographic analysis showed variations in the micromorphology, especially in the experimental group at the end of the demineralization model. Finally, there was no correlation between microhardness and surface roughness. The demineralization model decreased the microhardness, with the lowest reductions in the giomers groups. The effect of the demineralizing model on the surface roughness and topography showed an increase in specific patterns for the experimental and control groups. Therefore, their clinical use is recommended. Research Highlights: The demineralization model decreased the microhardness property of the evaluated materials, with better performance for the giomer groups.The effect of the demineralizing model on surface roughness showed an increase with specific patterns for the experimental and control groups.Although the materials presented changes in their microhardness, roughness, and topography, their clinical use is recommended. [ABSTRACT FROM AUTHOR]

Objective: To describe trends in cases and prevalence at birth rates of cleft lip and/or palate (CL/P) in Mexico between 2003 and 2019. Design: Ecological study. Setting: Multiple data sources systematically collected into a national epidemiological surveillance data warehouse. Participants: National Live Birth Information System. Main Outcome Measure(s): Both cases and prevalence at birth rates of CL/P in Mexico within a 17-year period were used as dependent variables. Results: At the national level there were 23 184 new cases of CL/P (average of 1364 per year) in the 32 states of Mexico, with an average prevalence at birth rate of 0.53 per 1000 live births. The states with the highest prevalence at birth rates of CL/P during the period were Hidalgo (1.59) and Jalisco (1.32), while the states with the lowest rates were Nayarit (0.22) and Durango (0.29). A slight decrease in both cases (z = −2.41, P =.016) and prevalence at birth rates (z = −2.58, P =.010) of CL/P was observed at the national level. States such as Durango, Puebla, Chiapas, Guerrero, Oaxaca, Mexico City, State of Mexico, Coahuila and Jalisco showed a clear downward trend (P <.05) in their prevalence at birth of CL/P between 2003 and 2019, while in Hidalgo its trend was upward (P =.05). Significant differences by sex and region were observed (P <.05). Conclusion: Some states consistently had the highest or lowest prevalence of CL/P. Decreasing trends in the overall prevalence at birth rates were observed. More detailed, epidemiological studies are necessary to adequately characterize CL/P in the Mexican population. [ABSTRACT FROM AUTHOR]

Purpose: To measure the demineralisation changes on human deciduous enamel produced by pH cycling after preventive treatment with Er:YAG laser irradiation, fluoride varnish application and a combination of the two.Materials and Methods: Sixty extracted human anterior primary teeth were assigned to six groups (n = 10). Group C: untreated; group L: Er:YAG laser; group TCP-NaF: Clinpro White (5% sodium fluoride and modified tricalcium phosphate); group CPP-ACP-NaF: MI varnish (5% sodium fluoride with casein phosphopeptide-amorphous and calcium phosphate); group L+TCP-NaF: Er:YAG + 5% sodium fluoride + modified tricalcium phosphate; group L+ CPP-ACP-NaF: Er:YAG + 5% sodium fluoride with casein phosphopeptide-amorphous and calcium phosphate. The samples were subjected to a 10-day pH-cycling regimen to create caries-like lesions, with 8 h in demineralising solution and 16 h in remineralising solution at 37°C. Enamel demineralisation was evaluated by laser fluorescence (DIAGNOdent) before and after pH cycling. The Mann-Whitney U-test and Wilcoxon tests were performed with statistical significance set at p ≤ 0.05.Results: The Wilcoxon test revealed statistically significant differences at baseline and after pH cycling in groups C (p = 0.02), L (p = 0.034) and L+TCP-NaF (p = 0.025) and the lowest percentage of healthy tooth substance compared to the other groups.Conclusions: The results suggest that the treatment protocols employed in groups TCP-NaF, CPP-ACP-NaF, and L+ CPP-ACP-NaF had similar effects in terms of preventing demineralisation, as reflected in a higher percentage of healthy dental structure maintained. Hence, these treatments are recommended for clinical use as an effective preventive measure. [ABSTRACT FROM AUTHOR]

ABSTRACT Sixty samples of human dentin were divided into six groups ( n = 10) and were irradiated with Er:YAG laser at 100 mJ-19.9 J/cm2, 150 mJ-29.8 J/cm2, 100 mJ-35.3 J/cm2, 150 mJ-53.0 J/cm2, 200 mJ-70.7 J/cm2, and 250 mJ-88.5 J/cm2, respectively, at 7 Hz under a water spray. The atomic percentages of carbon, oxygen, magnesium, calcium, and phosphorus and the Ca-to-P molar ratio on the dentin were determined by energy dispersive X-ray spectroscopy. The morphological changes were observed using scanning electron microscopy. A paired t-test was used in statistical analysis before and after irradiation, and a one-way ANOVA was performed ( P ≤ 0.05). The atomic percent of C tended to decrease in all of the groups after irradiation with statistically significant differences, O and Mg increased with significant differences in all of the groups, and the Ca-to-P molar ratio increased in groups IV, V, and VI, with statistically significant differences between groups II and VI. All the irradiated samples showed morphological changes. Major changes in the chemical composition of dentin were observed in trace elements. A significant increase in the Ca-to-P ratio was observed in the higher energy density groups. Morphological changes included loss of smear layer with exposed dentinal tubules. The changes produced by the different energy densities employed could have clinical implications, additional studies are required to clarify them. Microsc. Res. Tech. 78:1019-1025, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To determine and compare the cytotoxicity, odontoblast-like differentiation, shear bond strength (SBS) and Vickers microhardness of four commercial light-cured orthodontic adhesives., Methods: The orthodontic resins selected were Transbond XT - GI, Transbond Plus Color Change - GII (both from 3M Unitek), Enlight - GIII and Blugloo - GIV (both from Ormco). Samples were prepared, and leached monomers were obtained. Cytotoxicity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and deposited calcium was analyzed using Alizarin red staining (ARS). SBS and the adhesive remnant index (ARI) were determined using 120 human premolars. The Vickers microhardness test was performed on the resin discs., Results: All adhesives showed moderate to severe cytotoxicity (21-37%) and promoted similar formation of calcium deposits. A SBS of 6-8 MPa was achieved only by Blugloo (7.1 ± 2.4 MPa), and Enlight showed the lowest Vickers hardness score (40 ± 2.5 HV). Transbond Plus Color Change (score 0 = 42.9%) and Blugloo (score 0 = 46.4%) showed better ARI scores than Transbond XT (score 0 = 7.1%) and Enlight (score 0 = 3.6%)., Conclusion: On the basis of the properties evaluated, Blugloo seems to be the best option.

Objective: To describe trends in cases and prevalence at birth rates of cleft lip and/or palate (CL/P) in Mexico between 2003 and 2019., Design: Ecological study., Setting: Multiple data sources systematically collected into a national epidemiological surveillance data warehouse., Participants: National Live Birth Information System., Main Outcome Measure(s): Both cases and prevalence at birth rates of CL/P in Mexico within a 17-year period were used as dependent variables., Results: At the national level there were 23 184 new cases of CL/P (average of 1364 per year) in the 32 states of Mexico, with an average prevalence at birth rate of 0.53 per 1000 live births. The states with the highest prevalence at birth rates of CL/P during the period were Hidalgo (1.59) and Jalisco (1.32), while the states with the lowest rates were Nayarit (0.22) and Durango (0.29). A slight decrease in both cases (z = -2.41, P  = .016) and prevalence at birth rates (z = -2.58, P  = .010) of CL/P was observed at the national level. States such as Durango, Puebla, Chiapas, Guerrero, Oaxaca, Mexico City, State of Mexico, Coahuila and Jalisco showed a clear downward trend ( P  < .05) in their prevalence at birth of CL/P between 2003 and 2019, while in Hidalgo its trend was upward ( P  = .05). Significant differences by sex and region were observed ( P  < .05)., Conclusion: Some states consistently had the highest or lowest prevalence of CL/P. Decreasing trends in the overall prevalence at birth rates were observed. More detailed, epidemiological studies are necessary to adequately characterize CL/P in the Mexican population., Competing Interests: AcknowledgementsThis study was supported by a scholarship awarded by the National Council of Science and Technology of Mexico (CONACYT) to ECZ. Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: An increase in the acid resistance of dental enamel, as well as morphological and structural changes produced by Er:YAG laser irradiation, has been reported., Purpose: To evaluate the chemical changes associated with acid resistance of enamel treated with Er:YAG laser. Methods. Forty-eight enamel samples were divided into 4 groups (n = 12). Group I (control); Groups II, III, and IV were irradiated with Er:YAG at 100 mJ (12.7 J/cm(2)), 200 mJ (25.5 J/cm(2)), and 300 mJ (38.2 J/cm(2)), respectively., Results: There were significant differences in composition of irradiated groups (with the exception of chlorine) and in the amount of calcium released., Conclusions: Chemical changes associated with an increase in acid resistance of enamel treated with Er:YAG laser showed a clear postirradiation pattern characterized by a decrease in C at.% and an increase in O, P, and Ca at.% and no changes in Cl at.%. An increased Ca/P ratio after Er:YAG laser irradiation was associated with the use of higher laser energy densities. Chemical changes produced by acid dissolution showed a similar trend among experimental groups. Stable or increased Ca/P ratio after acid dissolution was observed in the irradiated groups, with reduction of Ca released into the acid solution.

The purpose of this study was to evaluate the shear bond strength, the adhesive remnant index scores, and etch surface of teeth prepared for orthodontic bracket bonding with self-etching primer and Er:YAG laser conditioning. One hundred and twenty bovine incisors were randomly divided into four groups. In Group I (Control), the teeth were conditioned with 35% phosphoric acid for 15 seconds. In Group II the teeth were conditioned with Transbond Plus SEP (5 sec); III and IV were irradiated with the Er:YAG 150 mJ (11.0 J/cm²), 150 mJ (19.1 J/cm²), respectively, at 7-12 Hz with water spray. After surface preparation, upper central incisor stainless steel brackets were bonded with Transbond Plus Color Change Adhesive. The teeth were stored in water at 37°C for 24 hours and shear bond strengths were measured, and adhesive remnant index (ARI) was determined. The conditioned surface was observed under a scanning electron microscope. One-way ANOVA and chi-square test were used. Group I showed the significantly highest values of bond strength with a mean value of 8.2 megapascals (MPa). The lesser amount of adhesive remnant was found in Group III. The results of this study suggest that Er:YAG laser irradiation could not be an option for enamel conditioning.