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Objective: To study the influence of bracket base meshes on shear bond strength and observe them using a scanning electron microscopy (SEM) before and after debonding., Methods: Ninety brackets were divided into nine groups of 10 samples each: G1-Alexander, G2-Mini Sprint ® Brackets, G3-In-Ovation R CCO, G4-Gemini SL Self-Ligating Bracket, G5-Classic mini 2G Stylus ® , G6-Gemini Metal Brackets, G7-Clarity TM Advanced, G8-Crystall-Ize ® , and G9-Ceramic Series Flexx 2G ® . Groups G1 to G6 and G7 to G9 consisted of metallic and aesthetic brackets, respectively. Initial photographs of all brackets were taken through SEM at 25X magnification. The brackets were then bonded to premolars using Transbond TM XT, and a shear bond strength test was conducted after 24 hours using an Instron machine at 1 mm/min. After debonding, the bracket meshes were observed using SEM., Results: Before bonding, 72.22% of brackets didn't present mesh defects, while 27.77% did. SEM analysis revealed that G4 and G5 presented defects in 100%, G7 in 40%, and G8 in 10%. The average shear bond strength of 9.67 ± 2.84 MPa and 11.21 ± 4.99 MPa were obtained for both metallic and aesthetic brackets, respectively. A Pairwise-Wilcoxon test with Benjamini-Hochberg correction was conducted to determine specific statistical differences between the groups, revealing significant differences based on bracket type and shear bond strength ( P < 0.009)., Conclusions: This study suggested that the shape of bracket meshes influenced shear bond strength.

Evaluate the prevalence and severity of caries in permanent teeth and their association with the treatment needs of 8-12-year-old Mexican schoolchildren. The cross-sectional study was conducted on 1139 8-12-year-old schoolchildren attending two public primary schools in State of Mexico. The study used the International Caries Detection and Assessment System (ICDAS) to examine the prevalence of caries and identify treatment needs in schoolchildren. Other variables considered were age, gender, oral hygiene, dental visits ≤6 months, toothbrushing frequency, and the mother's years of education. A logistic regression model was used to identify the association between independent variables and treatment needs. In all analyses, two-tailed p values ≤ 0.05 were considered statistically significant. The prevalence of caries lesions was 82.1% (82.2% boys vs. 81.9% girls) considering all lesion categories (ICDAS 1-6), while the distribution of the severity of caries was 17.9% (ICDAS 0), 13.9% (ICDAS 1-2), 28.3% (ICDAS 3-4) and 39.9% (ICDAS 5-6). The treatment needs index was 77.3%. The logistic regression model showed that the schoolchildren with moderate (ICDAS 3-4) and extensive carious (ICDAS 5-6) lesions were, respectively, 61% Odds Ratio ((OR) = 1.61; p = 0.036) and 77% (OR = 1.77; p = 0.013) more likely to present treatment needs. Other variables, such as poor oral hygiene (OR = 1.52; p = 0.009), the mother's low level of education (OR = 1.53; p = 0.007), and a lack of dental visits (OR = 1.42; p = 0.030) were associated with dental treatment needs. The results obtained show that the 8-12-year-old Mexican schoolchildren presented a high level of treatment needs for moderate and extensive carious lesions (ICDAS 3-6). These findings reiterate the importance of implementing oral health prevention, promotion, and intervention programs to help protect the oral health of school-age children., Competing Interests: The authors declare no conflict of interest., (©2024 The Author(s). Published by MRE Press.)

Purpose: To examine the association between educational level and the presence of periodontal disease in adults ages ≥ 50 years in Mexico., Materials and Methods: A cross-sectional study was conducted on 2098 Mexican adults, using data from the annual reports of the Epidemiological Monitoring System for Oral Pathologies from 2019-2022. Data were collected on sociodemographic characteristics such as gender, age, educational level, oral hygiene, and diabetes. Periodontal status was evaluated using the Community Periodontal Index (CPI) and was classified into: CPI &#61; 0 (healthy); CPI &#61; 1 (bleeding on probing); CPI &#61; 2 (calculus); and CPI &#61; 3 or 4 (pocket depth ≥ 4 mm). A multinomial regression model was used to estimate the odds ratio (OR) and the 95% confidence intervals (CI), using periodontal status as the result., Results: 39.9% of subjects presented periodontal pockets of ≥ 4 mm, 20.8% presented calculus, and 12.8% presented bleeding, while only 26.4% were classified as healthy. A low level of education (≤ 9 years) (OR &#61; 4.84; p 0.001), age ≥ 65 years (OR &#61; 1.33; p &#61; 0.025), poor oral hygiene (OR &#61; 6.86; p 0.001), smoking (OR &#61; 1.51; p &#61; 0.025), and diabetes (OR &#61; 1.73; p 0.001) were statistically significantly associated with the presence of periodontal pockets ≥ 4 mm., Conclusions: A low level of education is associated with worse periodontal status in adults aged 50 years or more. These findings reiterate the importance of implementing effective strategies and the incorporation of interventions for improving the access to and quality of services targeted at aging communities.

The characteristics of the temporomandibular joint (TMJ) are essential in orthodontic and prosthetic treatments. Previous studies have suggested an association between articular eminence inclinations (AEI) and occlusal plane characteristics using radiographs, but no bilateral analysis has been conducted using cone beam computed tomography (CBCT). Objective: This study aimed to investigate the specific characteristics of the occlusal plane inclinations associated with unilateral and bilateral AEI using CBCT. Methods: We conducted a cross-sectional study to evaluate 200 temporomandibular joints (TMJs) from 100 records obtained at the orthodontic department. We evaluated the association between the AEI, and occlusal plane characteristics like the cant of the occlusal angle, occlusal plane angles, inclination of the upper incisor to the Frankfort plane and palatal plane using both bivariate and multivariate analyses both unilaterally and bilaterally. Results: Our findings suggested statistically significant associations ( p < 0.050) between AEI (bilateral) and occlusal inclination parameters, including the cant of the occlusal plane (Coef. -0.38; 95%CI -0.70:-0.06; p = 0.017), occlusal plane angle (Coef. -0.39; 95%CI -0.740:-0.05; p = 0.024), and position of the upper incisor relative to the palatal plane (Coef. -0.34; 95%CI -0.63:-0.06; p = 0.016). Conclusion: This study suggests an association between dental inclinations and AEI, which reflects the anatomical characteristics of TMJ and its related dental structures.

Purpose: To evaluate the influence of the polymerization distance of monowave and polywave light curing units (LCUs) on the measured irradiance relative to the value reported by the manufacturer in relation to the physical properties of resin-based composites (RBCs)., Methods: Four LCUs were used: one monowave and three polywave. The irradiance was measured with a digital radiometer. Depth of cure (DC) and flexural strength (FS) tests were performed according to ISO 4049:2019 at polymerization distances of 0 mm and 5 mm., Results: The irradiance of all LCUs was higher than that reported by the manufacturer (>25-64%). The irradiance of the four LCUs was reduced when polymerization was performed at between 0 to 5 mm (paired t-test, P < 0.001). The DC at 0 mm was similar in all groups but was significantly decreased at 5 mm distance (ANOVA P < 0.001). FS showed differences among the LCUs at 0 mm (ANOVA P < 0.001) and was affected by the polymerization distance. The elastic modulus was unaffected by the LCU used or the distance (ANOVA P > 0.001)., Conclusions: The LCU must be positioned as near as possible to RBCs during the polymerization process, as increased distance negatively affects the depth of cure and flexural strength.

Objective: To examine the association between the level of marginalization and tooth loss in adults aged ≥50 years in Mexico., Methods: A retrospective cross‑sectional study was conducted on 2098 adults selected from communities presenting both high and medium levels of marginalization, with data obtained from the annual reports of the Epidemiological Surveillance System of Oral Pathologies 2019-2022. Analysis considered sociodemographic characteristics such as sex, age, and years of education. The prevalence of tooth loss was determined using the Decayed, Missing and Filled teeth (DMFT) index. Negative binomial regression was used to estimate rate ratio (RR) and 95% confidence intervals (CIs), using the presence of lost teeth as an outcome., Results: Most (62.4%) participants had lost at least one tooth, of whom 60.3% had a medium level of marginalization, 28.8% a high level, and 10.9% a very high level. More adults who lived in high or very high marginalization communities had lost teeth [RR=1.19 (95% CI 1.08 - 1.30)] than those living in communities with a medium level of marginalization. More males [RR=1.19 (95% CI 1.09 - 1.31)], adults ≥70 years [RR=1.77 (95% CI 1.57 - 1.99)], people who were illiterate [RR=1.60 (95% CI 1.35 - 1.88)] or who had poor oral hygiene [RR=1.26 (95% CI 1.15 - 1.38)] had also lost teeth., Conclusion: High and very high marginalization was associated with tooth loss in adults ≥50 years in Mexico. Effective oral health strategies are required to prevent tooth loss, as are interventions to improve access to and quality of dental services for marginalized communities., (Copyright© 2023 Dennis Barber Ltd.)

Purpose: To evaluate the effect of adding wollastonite and bioactive glass to an experimental mineral trioxide aggregate-like cement (MTA) on the dimensional stability, compressive strength, solubility, bioactivity, and marginal adaptation by scanning electron microscopy (SEM) and X-ray diffraction (XRD)., Methods: Four groups were evaluated at 7, 14, and 21 days: MTA Angelus, experimental MTA-like cement (MTA Exp), BG10 (MTA Exp+10 wt% bioactive glass), and WO20 (MTA Exp+20 wt% wollastonite). To evaluate marginal adaptation, extracted teeth were endodontically obturated and root-end cavities were prepared and filled with the tested materials., Results: Cements with bioactive materials showed minimal dimensional changes. Adding wollastonite or bioactive glass to MTA Exp reduces the compressive strength but does not affect solubility. Bismite (Bi 2 O 3 ), larnite (Ca 2 SiO 4 ), calcite (CaCO 3 ) and carbonated hydroxyapatite (Ca 5 [PO 4 ,CO 3 ] 3 [OH]) were identified in the four cements; ettringite (Ca 6 Al 2 [SO 4 ] 3 [OH] 12 ·26H 2 O) and bismutite ([BiO] 2 CO 3 ) were only observed in MTA Exp, BG10, and WO20. Cement-dentin interfaces were not observed after 14 days on the BG10 and WO20 cement composites due to the ettringite formation., Conclusion: Acicular growing crystals typical of hydroxyapatite were found on the surfaces of all cements. An improved marginal adaptation was observed with the addition of wollastonite or bioactive glass.

Purpose: To explore the relationship between of self-reported health (SRH) and educational attainment with pastyear dental visits in older adults in México., Materials and Methods: For this cross-sectional study, data were derived from the Mexican Health and Aging Study 2018 (MHAS-2018), which used a nationally-representative sample of older adults (50 years or older) in Mexico (n = 14,085). Variables taken from the MHAS questionnaire included residence (rural/urban), years of education, SRH, multimorbidity, pain severity, and past-year dental visits. A logistic regression model was used to identify the association between the variables and past-year dental visits., Results: While the percentage of past-year dental visits reported was 39.8%, this number declined with age [OR=0.76, p < 0.001], with older adults living in rural areas 34% less likely to report past-year dental visits than older adults living in urban areas. Older adults with no formal education were 73% less likely (OR=0.27; p < 0.001) to report past-year dental visits than older adults ≥10 years education. Older adults with poor SRH were 32% less likely (OR=0.68; p < 0.001) to report past-year dental visits than older adults with good/very good/excellent SRH. Sex, degree of multimorbidity, and pain level ([OR=1.37; p < 0.001] [OR=1.37; p < 0.001] and [OR=1.17; p < 0.001]) were all found to be positively associated with past-year dental visits in the study population., Conclusion: The present study highlights the association between poor SRH, a low level of educational attainment, and less frequent past-year dental visits, as well as the finding that past-year dental visits declined with age in the older adults sampled.

Literature reports indicate that during bracket removal there can be enamel damage. We compare the shear bond strength (SBS) and tooth enamel loss of four adhesive systems and identify the Ca/P ratio. Then a total of 20 premolars were divided into four groups of five each. After prophylaxis, photographs were taken at 35× with a scanning electron microscope (SEM) and analyzed with X-ray spectroscopy (EDS) at 250×. Brackets were bonded with Transbond™ MIP(G1), Transbond™ PLUS SEP(G2), Enlight(G3) and Stylus®(G4) adhesives, 24 h after were debonded with a Instron universal testing machine at 1 mm/min. All the brackets were photographed with the SEM. The amount of lost enamel was measured with AutoCad. All the results were measured with a significance level p < .05. The SBS general average at debonding was 7.94 ± 2.26 MPa, meanwhile the SBS for G1, G2, G3 and G4 was 9.38 ± 1.46, 6.28 ± 0.69, 9.08 ± 2.45 and 7.04 ± 2.64 MPa respectively. 90% of the samples had no enamel loss, 10% had enamel loss. Only two samples in G1 presented an enamel loss area of 0.34mm 2 and 0.80mm 2 respectively. From EDS analysis, the Ca/P ratio was 1.6 ± 0.05, 1.61 ± 0.03, 1.64 ± 0.83 and 1.59 ± 0.07 for G1, G2, G3 and G4 respectively; no statistically significant differences were found. We conclude that no association was found between the Ca/P ratio and enamel damage when brackets are removed. HIGHLIGHTS: Where enamel is lost, we observe fractures, steps, horizontal and vertical enamel loss. There is a loss of tooth enamel from 0.34 to 0.80 mm 2 with Transbond PLUS SEP. Structural loss of enamel is almost inevitable during the separation of the bracket., (© 2022 Wiley Periodicals LLC.)

Abstract: The aim of this study was to evaluate the association between sociodemographic factors and noncavitated and cavitated caries lesions in Mexican schoolchildren.This cross-sectional study was conducted in 2020 on 8-to-12-year-old schoolchildren of different socioeconomic status (SES). The caries was evaluated using ICDAS II, SES was evaluated using three categories---a high, middle, or low-income level---of the CONAPO. Multinomial logistic regression analyses were performed in order to ascertain the associations between socioeconomic factors and noncavitated and cavitated caries lesions.The prevalence of noncavitated lesions was 38.0% and cavitated lesions was 43.4% in permanent dentition. In all the samples, 50.6% of schoolchildren had poor oral hygiene. About 52.5% of the mothers and 64.7% of the fathers had less than 9 years of education. Schoolchildren with a low-income level have more cavitated lesions (ICDAS II 4-6) than schoolchildren with high-income level (56.3% vs 15.8%, P = .009). The multinomial logistic regression models showed that mother's level of education <9 years and low-income level were significantly associated with cavitated caries lesions (ICDAS II 4-6), [odds ratio = 1.79 (1.17 - 2.75); P = .007], [OR = 2.21 (1.23 - 3.97); P = .008], respectively. The socioeconomic level was not associated with noncavitated caries lesions (ICDAS II 1-3).An association was found between the presence of cavitated caries lesions and the subject's mother's level of education and a low-income level. Socioeconomic factors were found to be associated with inequalities in caries distribution in the age group studied., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

The clinically adequate shear bond strengths (SBS) should be from 2.8 to 10 MPa. The aim of this research is to observe tooth enamel loss through a scanning electron microscope (SEM) during the debonding of braces of four adhesive systems. Then, 100 premolars were used in 4 groups of 25 specimens each, for Transbond MIP (G1), Enlight (G2), Stylus (G3), and Transbond Plus SEP (G4). The research was done under the NOM ISO/TS 11405:2015. Gemini 3M were placed under the manufacturer's recommendations. The SBS test was done at 24 hr in an Instron electromechanical universal testing machine at 1 mm/1 min. Adhesive remnant index (ARI) was measured, all of the brackets where examined in the SEM. For the shear bonding strength G1 = 10.09 ± 2.73 MPa, G2 = 9.27 ± 3.99 MPa, G3 = 7.83 ± 4.46 MPa, and G4 = 6.40 ± 2.85 MPa statistically significant differences were found when comparing the four groups (p = .002). In the Tukey post hoc test, G1 versus G4 and G2 versus G4, statistically significant differences were found. For the ARI a value of 1 in 46%, followed by a value of 2 in 38%, a value of 3 in 13% and a value of 0 in 3% of the total samples, finding statistically significant differences (p < .001). In relation to the tooth enamel loss due to SBS, statistically significant differences were found (p = .326). G1 and G4 had not statistically significant differences. Even though our results concur with the appropriate clinical values, we observed tooth enamel loss with Transbond Plus SEP and Stylus., (© 2020 Wiley Periodicals LLC.)

Clinical procedures when shear forces are applied to brackets suggest adhesion forces between 2.8 and 10.0 MPa as appropriate. In this study dental enamel was evaluated by scanning electron microscopy (SEM) before and after removing the brackets. Thirty bicuspids (previous prophylaxis) with metallic brackets (Roth Inovation 0.022 GAC), Transbond Plus SEP 3M Unitek adhesive and Transbond XT 3M resin were used. The samples were preserved to 37°C during 24 hr and submited to tangential forces with the Instron Universal machine 1.0 mm/min speed load strength resistance debonding. Also the Adhesive Remanent Index (ARI) test was made, evaluating the bracket base and the bicuspid surface. All the bracket SEM images were processed with AutoCAD to determine the enamel detached area. The average value was 6.86 MPa (SD ± 3.2 MPa). ARI value 1= 63.3%, value 2= 20%, value 3= 13.3% and 33% presented value 0. All those samples with dental enamel loss, presented different situations as fractures, ledges, horizontal, and vertical loss in some cases, and some scratch lines. There is no association between the debonding resistance and enamel presence. Less than half of the remanent adhesive on the dental enamel was present in most of the samples when the ARI test was applied. When the resin area increases, the debonding resistance also increases, and when the enamel loss increases, the resin free metallic area of the bracket base decreases in the debonding., (© 2017 Wiley Periodicals, Inc.)