Acta odontologica latinoamericana : AOL最新文献

The aim of this study was to investigate the internal root canal anatomy of maxillary and mandibular premolars in a Brazilian subpopulation, in order to establish the prevalence of the different configurations proposed by Vertucci. Three hundred and ninety-eight cone-beam computed tomography scans were collected from a private imaging clinic database in Rio de Janeiro, including 217 maxillary and 226 mandibular scans. A total 1316 premolars (594 maxillary and 722 mandibular) were evaluated using an image viewer, and classified according to Vertucci. Two calibrated examiners determined the frequency of each morphological Type. A third examiner reviewed discordant cases. The Kappa test was applied to verify inter-rater agreement, and Fisher's Exact Test to verify gender-related differences. The most frequent root canal configurations of maxillary first and second premolars were Type IV (73.86%) and Type I (47.18%), respectively. Type I was the most prevalent in mandibular first and second premolars (80.59% and 95.86%, respectively). Only Types I and VIII presented a statistically significant difference between sexes. Type I was more frequent in females and Type VIII in males. A highly significant frequency of Type I was found in both mandibular first and second premolars, whereas the most frequent maxillary premolar root canal configuration was Type IV for first premolars and Type I for second premolars.

Acidic conditions can cause hydrolysis and accelerate degradation of resin composites (RCs). Since there are limited and controversial data on the effect of acids on bulk-fill RCs, this study assessed the surface roughness (SR) and flexural strength (FS) of these RCs under simulated carious and erosion conditions. Bars of Filtek Bulk Fill (FBF, 3M/ESPE), X-tra fil (XTF, Voco), Tetric N-Ceram Bulk Fill (TBF, Ivoclar/Vivadent), and Aura Bulk Fill (ABF, SDI) and a conventional RC [Filtek Z350XT (FZ, 3M/ESPE)] were allocated (n=15) to undergo caries or erosion conditions. The control group was kept in artificial saliva (AS). The bars were evaluated for SR change (final-baseline) and for three-point FS. Data were analyzed using ANOVA and Tukey's test. At the baseline (p <0.001), the SR of RCs ranked as follows: (TBF = XTF) < FBF (none differed from FZ) < ABF. The interplay between RCs and conditions affected SR change (p = 0.025). While after storage in AS, there was no difference among RCs, following carious and erosive conditions, ABF showed higher SR change. For FS (p <0.001), XTF > (FBF = FZ) > (TBF = FZ) > ABF, with no difference among control, carious and erosive conditions (p = 0.148). Depending on the restorative bulk-fill RCs, carious and erosive conditions roughen the surface but do not affect the FS of these materials.

Hypomineralization (MH) are controversial. The aim of this study was to compare need for treatment and status of restorations performed on first permanent molars in patients with and without MH. Retrospective design based on the clinical records of 153 patients who had received comprehensive care in 2014 at the Clinic of the Children's Comprehensive Dentistry Department (FOUBA) by 3 pediatric dentists (Kappa MH 0.94), and who attended periodical follow-up visits for at least 24 months. Need for treatment in first molars, and type and longevity of treatment were recorded (modified Ryge criteria /USPHS, Kappa 0.78). Results were compared between patients with MH and without MH. The Kruskal Wallis test was used to compare follow-up time, the asymptotic test was performed to compare proportions, and relative risk (RR) was calculated to compare need for treatment. Mean follow-up times for the 595 teeth analyzed were 61.7±20.1 months for Group without MH, and 57.5±23.9 months for Group with MH (p=0.0504). The percentages of teeth requiring at least one treatment were 7.2% in Group without MH and 27.5% in Group with MH (RR = 3.80, p <0.001). Of the teeth treated in Group with MH 23.1% required retreatment, while none of the teeth in Group without MH did. The need for treatment was approximately 4 times higher in molars affected with MH, with greater probability of retreatment.

The aim of this study was to analyze oral health actions in four municipalities in Brazil during the COVID-19 pandemic according to a theoretical framework model on oral healthcare management. It was a qualitative study carried out in two stages. A theoretical-empirical model on the significance of oral healthcare management was developed, following the Grounded Theory method. Fourteen dentists and five healthcare managers participated, through open interview. Subsequently, collaborative research was performed, and the model was applied to analyze the documents produced to address the pandemic by each of four municipalities in Santa Catarina State. The model provided a framework for analyzing actions for coping with the pandemic regarding oral health services. Actions were identified in all dimensions of the model: reduction in supply of dental care due to restricted access to elective services; search for biosafety care standards; dissemination of standardized science-based guidelines; attempt to maintain comprehensive dental assistance through re-adaptation of specialized services and collective actions; and relocation of oral health professionals to assist in other sectors. The oral health care management framework can serve as a reference for redesigning oral health actions and services in other municipalities during the COVID-19 pandemic, in a broader perspective.

The SARS-Cov-2 (COVID-19) pandemic changed the educational structure of dentistry courses and highlighted the importance of online tools. Understanding students' perception regarding these changes is essential to establishing future teaching-learning strategies to accommodate students' needs in higher education. The aim of this study was to assess students' perceptions of the Oral Radiology teachinglearning process before and during the COVID-19 pandemic. The sample consisted of students (n = 111) of the 2nd, 4th and 6th semesters of the dentistry course, who answered a questionnaire with 21 items: A) Students' demographic data (5 questions); B) Students' teaching-learning experiences during the pre-pandemic period (8 questions); and C) Students' teaching-learning experiences during the post-pandemic period (8 questions). Stuart-Maxwell tests revealed statistically significant differences between students' opinions before and during the pandemic when they were asked about the structure of the Oral Radiology module (p = 0.008); their previous experience with e-learning and teaching (p < 0.001); their thoughts about the importance of e-learning in Oral Radiology (p < 0.05); and the time they spent online for academic purposes (p < 0.05). Students seem to prefer on-campus activities (before COVID-19), but the pandemic increased their awareness of the importance of e-learning, the time they spent on online studies, and their knowledge of online educational tools.

The aim of this study was to compare the impact of the first year of wearing of a fixed orthodontic appliance on the Oral Health-Related Quality of Life (OHRQoL) between boys and girls, by means of a condition-specific instrument. The study included 69 adolescents aged 10 to 18 years, who were undergoing orthodontic treatment with a fixed appliance. Of the 69 adolescents, 38 were girls (55.1%) and 31 were boys (44.9%). They answered the Brazilian version of the Impact of Fixed Appliance Measure (B-IFAM) questionnaire three months (T1) and one year (T2) after the fixed appliance was installed. This questionnaire contains 43 questions, distributed across nine domains. The higher the scores, the more negative the perception of the adolescent concerning the impact of the fixed appliance on his/her OHRQoL. Sociodemographic and clinical variables were also analyzed, and statistical analysis was performed. For the domains, the effect size (the magnitude of the difference between girls and boys) and the minimal clinically important difference were also calculated. The adjusted regression showed that there was a significantly greater increase in the overall B-IFAM score in girls than in boys, indicating a more negative perception of the OHRQoL over the study time [Coefficient=11.77 (3.47- 20.60), p=0.006]. From T1 to T2, there was a significantly greater increase in the scores (more negative perception of OHRQoL over time) in girls than in boys for the domains aesthetics (p=0.034) and physical impact (p=0.011). These differences were clinically significant. The effect size (the magnitude of the difference) was moderate. The impact of wearing a fixed appliance on the OHRQoL was more negative in girls than in boys during the first year of orthodontic treatment.

Melatonin (MLT) is a hormone responsible for regulating several physiological processes. It has been shown that MLT can be an important mediator in bone formation and stimulation, promoting osteoblast differentiation. In clinical practice, in tissue regeneration procedures, it is necessary to use membranes or barriers, associated with biomaterials, or not. The aim of this in vitro study was to assess the effect of melatonin on the activity of osteoblastic cells, associated, or not, with a resorbable collagen membrane (Bio-Gideä). For this, mice-derived pre-osteoblastic cells MC3T3 obtained from the ATCC (American Type Culture Collection) were used. Cultured cells were subject to the following treatments: MLT with a concentration of 1mM, a Bio-Gideä membrane and a membrane associated with MLT (Bio-Gideä + MLT). Proliferation and cell viability assays and protein lysate (ELISA test) quantification for the BMP-2 protein were carried out, in periods of 72 hours, 7 days and 10 days. After analyzing the data (one-way ANOVA, alpha=5%) it was observed that when MLT was used in isolation, there was an increase in cell proliferation and viability in osteoblastic cells (p<0.05). But, when MLT was associated with resorbable membranes, there was an inverse behavior, both in terms of proliferation and viability (p<0.05). In the case of the ELISA test, no secretion of BMP-2 was detected in any of the analyzed groups. It is concluded that MLT has a stimulatory effect on osteoblasts, but, when associated with Bio-Gideä resorbable membranes, it does not show any viable action in osteoblastic cell stimulation.

The aim of this study was to measure the fluoride (F) and silver (Ag) ion concentration and the pH, over time, of 2 solutions of 38% silver diamine fluoride (SDF) produced in Argentina. The brand Fluorsilver® was established as Group 1 (G1) (Densell), and the brand FAgamin® (Tedequim) as Group 2 (G2), each with two different lots. The following were determined at time 0 (t0) and 30 days after opening (t30): a) fluoride concentration (w/v) by visible spectrophotometry b) Ag content (w/v) by atomic absorption spectrophotometry c) pH. Results: The data in the freshly opened bottles were for G1 lot1/lot2: a) 0.96/1, b) 8.3/7.8, c).11.5/11.3; G2 lot1/lot2: a) 11.5/9.9, b) 39/39, c) 7/6,9; and after 30 days, G1 lot1/lot2: a) 0.85/0.81, b) 7.2/8.2, c) 11.3/11.6; G2 lot1/lot2: a) 9.35/8.43, b) 38/38, c) 7.6/7.6. Conclusion In relation to the expected values (5.0-5.9% fluoride and 24.4-28.8% silver), the average concentration of fluoride and silver ions was lower for G1, but higher for G2. The pH was alkaline for G1 and neutral for G2. Over the 30 days, the content of fluoride and silver tended to decrease.

The aim of this study was to test two low-level laser therapy protocols by evaluating pain control, swelling and trismus in the postoperative period of lower third molar surgeries. This was a randomized, double-blind, placebo-controlled, crossover trial. Patients presenting two symmetrically impacted mandibular third molars were included. One side was randomly assigned for LLLT applied immediately after surgery (T1) and then after 24 (T2) and 48 hours (T3) (Protocol A). The other side received LLLT applied immediately after surgery and placebo after 24 and 48 hours (Protocol B). LLLT was given by intraoral application (660nm, 5 J/cm2, 10 s, 20 mW, 4 points) followed by extraoral application (789 nm, 30 J/cm2, 20 s, 60 mW, 8 points). The placebo application was similar to that of the experimental side but with laser simulation. The primary outcomes were pain control, swelling and trismus intensity at T1, T2, T3 and 7 days after surgery (T4). Data were analyzedbyANOVArepeated measures and Wilcoxon test (p<.05). The final sample consisted of 21 patients (42 teeth). There were no statistical differences for pain level between protocols A and B over time (p= .909), although the amount of analgesic medication was lower with protocol A at T2 (p=.022). There were no differences in swelling (p=.958) or trismus (p=.837) between the protocols used over time. Both protocols performed similarly for pain control, swelling and trismus. Therefore, for practical reasons, a single laser application in the immediate postoperative period could be indicated for the management of postoperative discomfort in lower third molar surgery.

The aim of this study was to evaluate the osseointegration of implants placed in rat tibia sites grafted with Deproteinized Bovine Bone (DBB) and Native Bone (NB). Twenty-eight rats were divided into two groups according to the type of substrate in which the implants were to be placed: NB - implants placed in native bone; DBB - implants placed in areas grafted with DBB. In the DBB group, the bone defect was made and filled with the bone substitute 60 days before placing the implant. The animals were euthanized 15 or 45 days after implant placement. Osseointegration was assessed by the removal torque, volume of mineralized tissues around the implants (BV/TV), bone-implant contact (%BIC), and bone between threads (%BBT). The implants placed in NB presented higher removal torque (8.00 ± 1.26 Ncm vs. 2.33 ± 0.41 Ncm at 15 days and 22.00 ± 2.44 Ncm vs. 4.00 ± 1.41 Ncm at 45 days), higher %BV/TV (47.92 ± 1.54% vs. 33.33 ± 4.77% at 15 days and 70.06 ± 0.91% vs. 39.89±5.90%at 45 days), higher %BIC (39.68 ± 5.02% vs. 9.12 ± 5.56% at 15 days and 83.23 ± 4.42% vs. 18.81 ± 7.21% at 45 days), and higher %BBT (34.33 ± 5.42% vs. 13.24 ± 8.72% at 15 days and 82.33 ± 3.13% vs. 22.26 ± 8.27% at 45 days) than the implants placed in DBB grafted areas. The degree of osseointegration was lower in implants placed in the area grafted with DBB than in NB in rat tibias.