Dental caries in children participating in a dentistry for infants program

To assess the impact of the "Dentistry for Infants" early dental care program run by Jacareí County (SP) by comparing the caries of individuals participating and not participating in this program. Methods: In total, 300 children between 0 and 48 months old were assessed in the following two groups: infants not participating in the program (G1, n = 100) and infants participating in the program (G2, n = 200). Each group was further divided according to age in subgroups of 0 to 24 months and 25 to 48 months. All children were clinically assessed for carious lesions using the visual-tactile method. The data were statistically analyzed using a paired Student's t-test, Mann-Whitney test, and c 2 test at a 5% significance level. Results: There was a significant difference in the prevalence (P) and mean index of deciduous teeth (deft) (C) that were decayed, indicated for extraction and filled, and the highest values were observed in G1 (p < 0.0001). The values were as follows: PG1, 73%; PG2, 22%; CG1, 3.45 ± 3.84; and CG2, 0.66 ± 1.57. Conclusion: Participating in the program positively impacted the infants' oral health.

Esthetic dental anomalies as motive for bullying in schoolchildren

Facial esthetics, including oral esthetics, can severely affect children's quality-of-life, causing physical, social and psychological impairment. Children and adolescents with esthetic-related dental malformations are potential targets for bullies. This study was aimed to present and discuss patients who suffered from bullying at school and family environment due to esthetic-related teeth anomalies. Providing an adequate esthetic dental treatment is an important step in their rehabilitation when the lack of esthetic is the main source of bullying. After dental treatment, we noted significant improvement in self-esteem, self-confidence, socialization and academic performance of all patients and improvement in parental satisfaction regarding the appearance of their children. It is imperative that both family and school care providers be constantly alert about bullying in order to prevent or interrupt aggressive and discriminatory practices against children and adolescents. Clearly, dental anomalies may be a motive for bullying.

Responses of dental pulp cells to a less invasive bleaching technique applied to adhesive restored teeth

To assess the cytotoxicity of 35% hydrogen peroxide (HP) bleaching gel applied for 15 min to sound or restored teeth with two-step self-etching adhesive systems and composite resin. Materials and Methods: Sound and restored enamel/dentin disks were stored in water for 24 h or 6 months + thermocycling. The disks were adapted to artificial pulp chambers and placed in compartments containing culture medium. Immediately after bleaching, the culture medium in contact with dentin was applied for 1 h to previously cultured odontoblast-like MDPC-23 cells. Thereafter, cell viability (MTT assay) and morphology (SEM) were assessed. Data were analyzed by two-way ANOVA and Tukey's test (a = 5%). Results: In comparison to the negative control group (no treatment), no significant cell viability reduction occurred in those groups in which sound teeth were bleached. However, a significant decrease in cell viability was observed in the adhesive-restored bleached groups compared to negative control. No significant difference among bleached groups was observed with respect to the presence of restoration and storage time. Conclusion: The application of 35% HP bleaching gel to sound teeth for 15 min does not cause toxic effects in pulp cells. When this bleaching protocol was performed in adhesive-restored teeth, a significant toxic effect occurred.

Microbiological analysis of dental casts stored long-term

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tratamento da classe II divisão 2 com aparelho de Herbst após o pico de crescimento puberal

Patients with Class II division 2 malocclusion and mandibular retrusion have limited treatment options after the growth peak, such as surgical-orthodontic treatment or mandibular advancement devices. Among bite-jumping devices, the Herbst appliance allows greater increase of mandibular growth since it does not require patient compliance and allows continuous use. This case report presents the treatment of a Class II division 2 malocclusion in a patient after growth peak, performed in two stages. The first stage included the upper incisors proclination and overjet increase with multibracket appliance to benefit next stage. The second stage involved mandibular advancement using Herbst appliance aiming to correct the Class II molar relationship. The treatment resulted in a stable occlusion with periodontal health, normal functions and facial aesthetics improvement. Dental and skeletal changes arising from treatment could be assessed by cephalometric analysis and superimposition of pretreatment and post-treatment cephalometric tracings. Antero-posterior discrepancy was corrected by means of dental movement as well as by mandibular growth increment stimulated by the Herbst appliance.

Estabilidade oclusal a longo prazo de Classe II, divisão 1, após tratamento com extração de pré-molares

Patients are looking for esthetic and functional changes when seeking orthodontic treatment and expect the remaining of a stable occlusion. Occlusion stability is one of the goals of the orthodontist; however, dental relationships changes in long-term can occur leading to a relapse of the treatment. Teeth and shape of arches tend to return to the original form, been the retention phase important after the appliance removal, even after several years of post-treatment. This article approaches a submission of a clinical case of Class II division 1 treated with extraction of premolars analyzing its long-term stability.

Modificação de forma e dimensões dos arcos superior e inferior obtidas em modelos de estudo após expansão rápida da maxila com o aparelho hyrax

The aim of an orthodontic treatment is the achievement of a balanced, esthetic and, most of all, stable, intra and inter arches relationship. A common problem observed in occlusion is posterior crossbite and atresic maxilla. This problem may be treated by slow expansion, rapid expansion or surgically assisted expansion. For the present study cast models of 14 children between 7 and 11 years old were evaluated. There were 7 male and 7 female subjects that presented posterior crossbite and needed rapid maxillary expansion. The Hyrax appliance performed the therapy for correction of this transversal alteration, which is a common possibility in the treatment of this malocclusion. It was observed that the distance between the upper first molars and upper cuspids increased significantly; the length of the upper arch decreased and its perimeter increased significantly. At the lower arch there were no dimensional changes.

Efecto del blanqueamiento dental con peroxido de hidrógeno al 35% en la resistencia de unión de dientes restaurados con resina compuesta

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of different bleaching protocols on dental enamel and composite resin

To evaluate changes in microhardness, roughness and surface morphology of dental enamel and composite resin after different tooth bleaching techniques. Material and Methods: Dental fragments from bovine incisors with composite resin restorations were submitted to different bleaching protocols: G1 – daily 8 hours application of a 10% carbamide peroxide (CP) gel during 21 days; G2: 3 applications of 15 minutes of a 38% hydrogen peroxide (H2O2) gel; G3: 38% H2O2 gel associated to irradiation with LED (470nm) during 6 minutes. The Knoop micro hardness of enamel and composite resin were evaluated at 1, 7, 14 and 21 days for G1, and after 1, 2 and 3 sessions for G2 and G3. The roughness and superficial morphology (atomic force microscopy) were evaluated before and at the end of the bleaching treatment. The data were analyzed by Mann-Whitney and Wilcoxon tests (=5%). Results: Significant reduction on enamel hardness was observed after 2 and 3 sessions for G2 and G3. For composite, the reduction occurred after 21 days for G1, and after 3 sessions for G2 and G3 (p<0.05). Significant reduction on roughness and superficial morphology were observed only for enamel of G1 group (p<0.05). Conclusion: The 10% CP gel promoted only superficial alterations on dental enamel, while the 38% H2O2 gel promoted mineral reduction of this dental tissue. All the bleaching protocols promoted reduction on hardness of composite resin.

Effect of hydrogen-peroxide-mediated oxidative stress on human dental pulp cells

To evaluate the effect of the oxidative stress on human dental pulp cells (HDPCs) promoted by toxic concentrations of hydrogen peroxide (H2O2) on its odontoblastic differentiation capability through time. Methods HDPCs were exposed to two different concentrations of H2O2 (0.1 and 0.3 μg/ml) for 30 min. Thereafter, cell viability (MTT assay) and oxidative stress generation (H2DCFDA fluorescence assay) were immediately evaluated. Data were compared with those for alkaline phosphatase (ALP) activity (thymolphthalein assay) and mineralized nodule deposition (alizarin red) by HDPCs cultured for 7 days in osteogenic medium. Results A significant reduction in cell viability and oxidative stress generation occurred in the H2O2-treated cells when compared with negative controls (no treatment), in a concentration-dependent fashion. Seven days after H2O2 treatment, the cells showed significant reduction in ALP activity compared with negative control and no mineralized nodule deposition. Conclusion Both concentrations of H2O2 were toxic to the cells, causing intense cellular oxidative stress, which interfered with the odontogenic differentiation capability of the HDPCs. Clinical significance The intense oxidative stress on HDPCs mediated by H2O2 at toxic concentrations promotes intense reduction on odontoblastic differentiation capability in a 7-day evaluation period, which may alter the initial pulp healing capability in the in vivo situation.

Bone-implant contact around crestal and subcrestal dental implants submitted to immediate and conventional loading

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES