Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Aim: Sufficient polymerization remains as crucial for composites to prevent discoloration. Both LEDs and halogen units are used for polymerization and different curing modes are improved to overcome inadequate polymerization. This in vitro study investigated staining susceptibility of a nano-hybrid resin composite light-cured in different modes and immersed in different staining media. Methods: Disc-shaped specimens were prepared from nano-hybrid resin composite (Filtek Z550) and light-cured according to following modes: Halojen (GI), LED standard (GII), LED pulse (GIII) or LED ramp (GIV). Half of the specimens of each group (n=7)  were stored in one of the staining media (red wine or coffee) for 10 min/day during experimental period. Measurements were performed using spectrophotometer according to CIEL*a*b system at baseline and on 7, 28 and 56 days. Colour differences (∆E) between groups were submitted to statistical analysis. Results: Regarding 7-day evaluation, colour change values of specimens immersed in coffee revealed no remarkable difference among curing modes (p>0.05); whereas specimens in GIV were significantly less stained compared to specimens in GII and GIII when immersed in red wine. Regarding 56-days of evaluation, specimens of GIV showed statistically significant colour change in red wine compared to other groups. However specimens in GI revealed the least staining after 56-days of coffee immersion, and this result was statistically different from LED groups. Conclusion: This study suggest that light-curing mode influences the staining susceptibility of the tested composite. Composites polymerized with halogen unit showed lower staining than all LED modes. Despite novel light sources, halogen units may still used reliably at clinics.

The purpose of this study was to evaluate the effect of the use of the combined auxiliaries of oral hygiene with whitening agents on the micro-hardness and micro-morphology of dental enamel. Materials and Methods. 40 human incisors were used and sectioned to obtain 4x4mm samples and divided into four study groups. Group 1: Electric brushing with Toothpaste (BTP); Group 2: Electric brushing with Toothpaste+mouthwash (BTP+MW); Group 3: Electric brushing with Toothpaste+whitening pen (BTP+WP); Group 4: Electric brushing with Toothpaste+mouth wash+whitening pen (BTP+MW+WP). Samples were submitted toVickers micro-hardness test and visualized using scanning electron microscopy (SEM). Results. All groups, with the exception of group 1, showed a decrease in micro-hardness values after applying the treatments (p<0.05). Likewise, when comparing the values after the treatments between the groups, significant statistical differences were found in all of comparisons except for those of groups 2 and 4. SEM images showed changes in the morphology in all the study groups with the exception of group 1. Conclusion. Significant changes such as decrease in micro-hardness as well as in the topography of the enamel surface such as elevations, craters, porosities and etching patterns were founded after the use of the combination of auxiliaries of oral hygiene with whitening agents.  

The aim of this study was to evaluate mechanical properties of six new-generation all-ceramic materials for CAD/CAM (Lava Ultimate [LU], VITA Mark II [VM], InCoris TZI [IC], IPS e.max CAD [EM], VITA Suprinity [VS], IPS Empress CAD [EC]) and two different provisional restoration CAD/CAM materials (Telio CAD [TC], Vita CAD-Temp [VC]) after different storage conditions. 36 bar-shaped samples of 4 mm in width and 14 mm in length with 1.2 mm thicknesses were prepared from each material group (N=288). The specimens from each material were kept under three different storage conditions (n=12): under dry conditions at room temperature; 37°C distilled water for 7 days; and 37°C distilled water for 7 days followed by 10,000 thermal cycles. All specimens were subjected to a 3-point flexural test with a crosshead speed of 1.0 mm/min. The specimens were loaded until failure. Twelve fractured specimens after the flexural test from each group were used for the Vickers hardness test (under 300 gf of loading in 15 seconds). The flexural modulus, flexural strength and Vickers hardness values were separately analyzed with two-way analysis of variance, Tukey’s multiple comparison tests at a significance level of p<0.05. There were statistically significant differences between materials and storage conditions according to flexural modulus, flexural strength and Vickers hardness values (p<0.05).  The flexural strength, flexural modulus and Vickers hardness values of LU, VC, TC, VS and IC decreased after water storage followed by thermal cycling (p<0.05). The mechanical properties of provisional restoration CAD/CAM materials had showed a significantly decrease after water storage followed by thermal cycles but their mechanical properties were acceptable for fabrication of provisional restorations. The mechanical properties of VM, EC and EM were not affected by different storage conditions whereas IC and VS were affected.

We evaluated an infiltration anesthesia simulation model (IAM) and a conduction anesthesia simulation model (CAM) on the perception of learning by Mexican dental students. Our aim was to compare the perception of learning by dental students trained with two distinct dental anesthesia simulation model (DASM) with dental students who were not trained with a DASM. 3 groups participated in the study: G1 (N=12 students) learned to block the mental nerve (BMN) by participating in a theoretical lecture (stage 1) and a clinical demonstration (stage 2); G2 (N=12 students) learned the BMN by participating in the stage 1, stage 2, and training with the CAM; G3 (N=12 students) learned the BMN by participating in the stage 1, stage 2, and training with the IAM. The groups performed the BMN in a clinical exercise. Working-time of all participants was timed. Perception of learning for all participants was evaluated with a 5-point Likert Scale. The results showed that statistically significant differences were found between score of G1 and score of G2 and score of G3 (P<0.05).  No statistically significant differences were found between scores of G2 and scores of G3. G1, G2 and G3 showed an average working-time of 12:42 minutes, 9.75 minutes and 8:03 minutes, respectively (P<0.05). We concluded that the IAM and CAM showed a positive impact on the perception of learning, and the students trained with the IAM showed a shorter working time compared with the students trained with the CAM.

Objective: Bruxism is a jaw muscle activity disorder characterized by clenching or grinding of the teeth and can be seen in both children and adults. The purpose of this study is to evaluate the parental knowledge about bruxism in children. Methods: A cross-sectional study was conducted with 265 parents whose children were attended at University of Mersin pediatric dentistry and oral and maxillofacial surgery clinics. Children’s ages varied from 6 months to 16 years old. A 20-questioned questionnaire was used to collect the data. IBM SPSS Statistics 22 for statistical analysis (SPSS IBM, Turkey) program was used for the analysis. Results: A total of 265 parents (159 were female and 106 were male) participated in the study. The majority of the parents were between the ages of 31-40 (60.8%). The rate of clenching and grinding of teeth during sleep (21.5%) was higher than the rate when they were awake (7.2%). The ratio of the parents seeking treatment for their children because of this harmful habit was very low (3.8%). The majortiy of parents  (37.7%) reported that they seek help from dentists. The participants believed that bruxism was associated with dental problems (33.6%) and emotional factors (32.8%). A significant difference was found between the educational background of the parents and the ability to define bruxism. Conclusion: Parents had inadequate knowledge about bruxism in children and this was mostly related to the educational background of the parents.

Introduction: The prevalence of pathological conditions that appear as radiopacities at the level of the soft tissues in panoramic radiographs is a problem that occurs worldwide in the population, being this radiographic finding the initial diagnosis of other systemic affections. Objectives: the aim of this research was to identify the frequency of mineralized radiopacities that are found at the soft tissue level in panoramic radiographs. Material and methods: it was analyzed 347 radiographs of patients over 20 years of age, treated in the “Clínica Docente Odontológica” of the Universidad Católica de Cuenca, Sede Azogues, Ecuador from December 2017 to may 2018. Results: a prevalence of 0% of tonsillolith and atheroma was found, 1% of calcified lymph nodes and of electrolytes, 2% of sialolith, 4% of unilateral stylohyoid ligament calcification, 23% of calcification of bilateral stylohyoid ligament and 65% did not present calcifications of the soft tissues. Conclusion: it was possible to identify that the most frequent radiopacity at soft tissue level is the calcified bilateral stylohyoid process.

Understanding the possible effects that a patient’s psycho-neurobiological processes (such as the nocebo effect) may have on the every-day dental treatments, could assist the clinicians in preventing the onset of adverse events not related directly with the clinical procedure. At the same time, employing pathways to trigger plausible placebo effects could aid the clinician to enhance the outcome of ordinary clinical procedures and the patient’s perspective. Identified factors, which could lead both to positive or negative effects, may be present in different ways. Prior personal experiences, second-hand information, alternative medicine, catastrophizing or patient motivation; all could have an indirect effect in the treatment outcome. A well-informed clinician should use such factors to individualize each patient treatment.

.

Social health inequalities (or inequities) continue to represent a great challenge for public health research worldwide. Since 1991, the World Health Organization established that the study and analysis of health inequalities represented a priority for all countries. To better guide methodological and practical implications of health inequalities, research on this topic should present a solid theoretical model, able to impact future public health policies.  Previous studies of health inequalities in Latin America are often inspired from abroad experiences, encouraging the reproduction of mainly European theoretical positions and methodologies. However, especially when it comes to  this topic, it is known the important role of the social context and culture, playing an important role in promoting differences in health outcomes. From this perspective, to operationalize the different social determinants in health, a critical perspective and thoughtful analysis of the context is mandatory.  In order to provide a critical analysis and useful tools for both research and health decision making, we recommend that the theoretical and methodological approaches used in social health inequalities research must be well adapted to the specific contexts; that health social stratification must be assessed as a priority; that individual and the wider health determinants must be well characterized; and that the theoretical justification of the methodological decisions made in the studies and the selected measures must be explicit and should answer specific hypotheses.  This research provides a brief historical background, to share the basis for the conceptual evolution of social health inequalities; the main underlying concepts related to the definition of health inequalities (social determinants, equity, justice, stratification and social gradient in health); and some recommendations for the future perspectives of health inequalities research in Latin America.

The use of phosphate buffered saline (PBS) as an intracanal medication triggers a biomineralization process within mineral trioxide aggregate (MTA) apical plugs during the apexification process in teeth with incomplete rhizogenesis. However, no consensus is available in the literature regarding a restorative protocol for this type of treatment. Thus, the objective of this study was to use scanning electron microscopy (SEM) to evaluate the processes of biomineralization and adhesion in a restorative protocol for teeth with simulated incomplete rhizogenesis. Methodology: Root sections with a thickness of 2mm and cavities with a diameter of 2mm were used. The sections were randomly prepared and filled with the following materials: Group 1 (n=12), ProRoot MTA; and Group 2 (n=12): MTA Exp. Subsequently, the samples were immersed in PBS for 35 days. Every 5 days, the PBS was replaced, and the precipitates were collected, dried, and weighed. Two samples from each group were analyzed by SEM. Moreover, 24 single-rooted teeth were standardized, incomplete rhizogenesis was simulated, and 5-mm-long apical plugs were created with Pro Root MTA. As an intracanal medication, PBS was used for different periods of time: Group 1:48 h; Group 2:7 days; and Group 3:15 days. Then, fiberglass posts were cemented with the REBILDA® Post System. The samples were prepared and analyzed by SEM. Results: ProRoot MTA and MTA Exp effectively promoted the formation of carbonated apatite precipitates and biomineralization with dentin. ProRoot MTA yielded more carbonated apatite precipitates compared to MTA Exp (p=0.0536). The use of PBS as an intracanal medication for 7 and 15 days promoted intratubular mineralization (MIT), and treatment for 15 days was more effective (p < 0.05). The REBILDA® Post System effectively promoted the microimbrication of the adhesive system and the formation of resinous tags with lateral adhesive branches. Conclusion: Apexification with MTA associated with the use of PBS as an intracanal medication for 15 days, in addition to the use of the REBILDA® Post System, seems to be a feasible restorative protocol.