Resumo em Inglês:

Abstract Aim: To evaluate the relationship between palatal bone height and facial types using cone beam computed tomography (CBCT) images. Methods: The study sample consisted of 110 CBCT images. Subjects aged 18 to 35 years old were classified as brachyfacial, mesofacial and dolichofacial, according to SN.GoGn angle, measured in cephalometric analysis with Nemotec 3D software. Three observers evaluated the bone height of the palate in the anterior region, at the level of the maxillary first premolars. The measurements were performed in sagittal and coronal views, in median and paramedian regions of the palate, also using Nemotec 3D software. Measurements were repeated after 15 days on 25% of the sample to analyse intra and interobserver agreements by CCI test. Analysis of variance was performed to calculate statistical differences between the bone heights of the three facial types, with a significance level of 5%. Results: The correlation level of intra-observer agreement was excellent. No significant differences were observed between the palatal bone height in the region of first premolars and the different facial types (p>0.05). Conclusions: Based on CBCT evaluations, there is no association between palatal bone height and facial morphological patterns.

Resumo em Inglês:

Abstract Aim: To compare the masticatory performance associated with different rehabilitation strategies for patients with edentulous mandibles. Methods: one portion of the test food "Optocal" was provided to groups: Natural Dentition (n = 15), Mandibular Fixed Implant-Supported Prosthesis with Maxillary Fixed Prosthesis (n = 8), Mandibular Fixed Implant-Supported Prosthesis with Maxillary Removable Prosthesis (n = 14), Mandibular Implant-Retained Overdenture with Maxillary Removable Prosthesis (n = 16), and Complete Dentures (n = 16). The portion was collected after 40 chewing strokes, and then passed through a stack of eight sieves with decreasing apertures. Masticatory performance was determined by weighing the portion of food on each sieve. Results: the masticatory performance was: 71.00% for Natural Dentition, 41.57% for Mandibular Fixed Implant-Supported Prosthesis with Maxillary Fixed Prosthesis, 31.44% for Mandibular Fixed Implant-Supported Prosthesis with Maxillary Removable Prosthesis, 27.70% for Mandibular Implant-retained Overdenture, and 14.33% for Complete Dentures. The data were statistically compared using Student's t-test (p < 0.05). Natural Dentition and Complete Denture groups were statistically different from all other groups, with the Natural Dentition and Complete Denture groups exhibiting the highest and lowest masticatory performance values, respectively. Conclusions: Osseointegrated implants improved the masticatory performance of all implant-supported groups compared to the Complete Dentures group.

Resumo em Inglês:

Abstract Aim : To compare the retention of glass ionomer cement (GIC) used as fissure sealant with a resinbased sealant. Methods: Six- to nine-year-old children (n=96) with all permanent first molars in occlusion were examined and assigned to two groups: GIC sealant or resin-based sealant. The sealants were applied according to the manufacturers' recommendations. The assessment of sealant retention was performed at two-month interval sessions (n=6), when each sample was scored according to the following criteria: complete retention, partial retention or complete loss. The visual and tactile examinations were carried out with a WHO probe, mouth mirror, air syringe and artificial light. The data were submitted to descriptive statistics and survival analysis. Results: A total of 384 occlusal surfaces were analyzed. Independent of the tooth and evaluation time, slightly better results were achieved by the resin-based sealant, but the difference was not statistically significant. Conclusions: GIC and resin-based sealants achieved similar results with regards to retention during a one-year follow-up period.

Resumo em Inglês:

Abstract Aim: To evaluate the presence of failures in prosthetic screws and whether these failures are related to the type of prosthesis, abutment angulation and presence or not of intermediate. Methods: Two-hundred and sixty-seven patients were evaluated at the Federal University of Santa Catarina, totaling 971 external hexagonal implants in place for at least one year. A Tobit regression model for censored variables was used and the explanatory variables were subjected to percentage analysis. Results: The results demonstrated a relationship between the failure in prosthetic screws and the investigated factors with a significance of F=0.003 and p<0.05. The percentage analysis showed that the prosthetic screw failed in 8.82% of 238 unitary prostheses and 10.1% of 773 multiple prostheses. Among 912 abutments, 9.43% failed and in the 59 angled abutments, failures appeared in 15.25%. A total of 200 prostheses were placed over the implant platform and 13% failed. A total of 771 prostheses were made over abutment and 8.95% of these screws failed. Conclusions: Through multiple linear regression it could be concluded that the type of prosthesis showed no significant influence on the prosthetic screw failure, but other variables were related to this mechanical failure. There was a significant relationship among the variables, demonstrating the need for greater attention in choosing the type of prosthesis, the abutment angulation and whether the prosthesis will be placed directly on the implant platform or on the abutment.

Resumo em Inglês:

Abstract Aim: To evaluate if gypsum mixed with different water types, with their different compositions influence the dimensional change, surface roughness and compressive strength of type IV and V gypsum specimens. Methods: Sixty specimens were fabricated from metal matrices and divided into six groups (n=10) according to the used type of gypsum and water: G1, G2 and G3 - type IV gypsum and tap, mineral and distilled water, respectively; G4, G5 and G6 - type V gypsum and tap, mineral and distilled water, respectively. Water/powder ratio followed the manufacturer's recommendations (19 mL/100 g) in all groups. The same specimens were used for all tests. A micrometer dial evaluated the dimensional change. The surface roughness of three random points was determined with a rugosimeter; a universal testing machine performed the compressive strength test. The data were subjected to analysis of variance (ANOVA). Results: There was no statistically significant difference (p>0.05) between the three types of water in the studied variables. There was statistically significant difference (p<0.05) between the gypsum mixes for the dimensional change variable. Conclusions: The different water types, with their different compositions, did not influence the analyzed physical and mechanical properties.

Resumo em Inglês:

Abstract Aim: To assess the profile, quality of life and the presence of Temporomandibular Disorders (TMD) in elderly caregivers. Methods: Thirty-nine caregivers who worked in six long-stay institutions for the elderly in three different municipalities participated in the study. The research instruments were the WHOQOL-BREF, the Fonseca questionnaire and the socio-demographic questionnaire. The Kruskal-Wallis test with the Dunn's correction was performed at a level of 5%. Results: Females accounted for 94.9% of the sample. The average monthly wage was R$ 832.00. The average working week was 39 hours. The WHOQOL dominions showed the following averages: 74.25 Physical; 70.33 Psychological; 65.79 Social Affairs; 58.38 Environment. Mild DTM was present in 43.6% of the caregivers, of which 7.7% were moderate, 5.2% severe, 23.0% of the professionals were asymptomatic and 20.5% did not answer. The association between TMD and the quality of life showed p=0.6752. Conclusions: It was concluded that there was no relationship between the quality of life and symptoms of temporomandibular dysfunction among the caregivers of elderly in this study.

Resumo em Inglês:

Abstract Aim: To investigate whether the removal and reseating of the abutment influences the retention of Morse taper implant system. Methods: Two Morse taper implant systems were selected: Bicon Dental ImplantTM system (Bicon, LLC, Boston, MA, USA) and Kopp Implant(r) system (Kopp(r), Curitiba, PR, Brazil). In both systems, the abutment is connected to the implant with a locking taper. To seat the abutment, the same vertical force was applied in both systems. It was measured the compressive force necessary to engage effectively the locking taper connection and the tensile force to displace it. Results: The compressive force was determined by four activations in each abutment-implant set, and the sum of these forces was 21 N and 17 N in the BiconTM and Kopp(r) systems, respectively. Next, a tensile test was performed, revealing that the BiconTM system presented a 208 N resistance, whereas it was 194 N in the Kopp(r) system. Other three rounds of compression and tensile loads were applied, removing and reseating the abutment. We obtained the following tensile values: 367 N, 500 N and 756 N in the BiconTM System and 336 N, 360 N and 420 N in the Kopp(r) system. Conclusions: When the sets were subjected to repeated rounds of compressive and tensile forces, displacing and reseating the abutment, the tensile value increased.

Resumo em Inglês:

Abstract Aim: To evaluate canal transportation and centering ability of Protaper and WaveOne systems in curved root canals by cone-beam computed tomography. Methods: Twenty human molars were randomly divided into two groups according to the system used: Group GP (ProTaper Universal(r)) and group GW (WaveOne(tm)). CT scans were performed before and after the chemo-mechanical preparation on three points: 2 mm, 3 mm and 4 mm from the tooth apex. The cuttings in dentin were measured and results were statistically analyzed. Results: In GP, there was higher percentage in transport at 2 mm and 4 mm toward the mesial wall of the tooth root compared to GW (p<0.05). There was no difference between the systems regarding their centering ability. Conclusions: None of the systems was able to touch all the dentin walls and stay centered during the chemical-mechanical preparation.

Resumo em Inglês:

Abstract Aim: To evaluate the sorption, solubility and color change in two lining materials after 120 days of immersion in either sodium perborate or artificial saliva. Methods: Thirty disk-shaped specimens (15×3 mm) of each material, Mucopren(r) soft (MS) and Elite(r) soft (ES) were manufactured and divided into two groups. The specimens in the control group (CG, n=15) were stored in artificial saliva at 37 °C. The specimens in the experimental group (EG, n=15) were stored in artificial saliva at 37 °C and immersed in sodium perborate daily for 5 min. The analysis of sorption and solubility was based on the initial dry weight and on the wet and dry weights after immersion. The color was assessed with a portable spectrophotometer and the NBS system. ANOVA and Tukey test (p<0.05) were used to analyze color and sorption. The solubility was analyzed by KruskalWallis test (p<0.05). Results: Sorption was higher in the EG group (0.31±0.08) than in the control group (0.26±0.05), and higher in Elite(r) soft relining (0.34±0.07) than in Mucopren(r) soft (0.23±0.06). There was no interaction between the factors. Elite(r) Soft presented a higher solubility when immersed in artificial saliva (CG: 0.16±0.07 and EG: 0.13±0.06; p=0.00). Mucopren(r) soft showed no solubility in either treatment. Regarding the color changes, there was a significant difference between the groups (CG: 9.2±1.2 and EG: 9.9±1.2; p=0.025) but not between the materials (Mucopren(r) soft: 9.4±1.3 and Elite(r)soft: 9.7±1.0; p=0.34). Using the NBS system, we verified that both materials presented a high color change. Conclusions: The daily use of sodium perborate promoted changes in the liners' sorption and color. Elite(r) soft relining was more prone to changes than Mucopren(r) soft.

Resumo em Inglês:

Abstract Aim: To evaluate the experience, knowledge and attitudes of dentists and oral health technicians (OHTs) who work in Basic Health Units in the city of Curitiba, PR, Brazil, regarding cases of abuse against children and adolescents. Methods: In this observational study, three hundred eighty-three questionnaires (validated for Brazilian Portuguese) were sent to dentists and OHTs who work in public health units. The response rate was 38.12% (n = 146) for dentists and 40% (n = 77) for OHTs. Results: The mean age of the dentists was 40±8.29 years, and 53.43% treated more than 10 children per week. The OHTs' mean age was 45.39±9.71 years, and 62.35% attended to more than 10 children per week. Although the dentists perceived 185 suspected cases of maltreatment, only 35.67% were reported to authorities. In the OHT group, 22.08% were reported to authorities. Sixty-eight dentists (47%) and 11 OHTs (14.28%) reported having treated at least one case of orofacial trauma in the previous 6 months, totalizing 166 orofacial traumas. About the mechanism for reporting suspected cases, 83% of the respondents knew how to report. Over 50% of the responses concerning why the professionals did not report cases of physical violence against children included fear of retaliation and difficulties in diagnosis. Conclusions: Suspected cases of maltreatment against children and adolescents are underreported. More information is required to recognize suspected maltreatment cases and notify authorities.

Resumo em Inglês:

Abstract The cementation of thin ceramic veneers employing fluid light-activated resin-based materials is a common procedure in the dental practice. Aim: To evaluate the influence of ceramic thickness and shade on the degree of conversion (DC) of a flowable light-activated material. Methods: flowable resin composite (Tetric N-Flow - shade A1) was light-activated through ceramic discs of two shades (IPS Classic - A1 and A3) in three thicknesses (0.5, 0.7 and 1.0 mm). For control, the resin composite was light-activated without ceramic interposition. DC was evaluated by FTIR (n=5). Data were analyzed by one-way ANOVA and Dunnett's T3 test (α=0.05). Results: Statistically significant differences between groups were observed (p<0.001). Control group (without the interposition of ceramic) showed the highest mean for DC (71.9± 1.7). Considering the interposed ceramic disc groups, the highest DC values were obtained when 0.5 and 0.7 mm A1 ceramics were used (64.6±1.2 and 64.4 5.0, respectively) and the lowest DC values were obtained for 0.7 and 1 mm A3 ceramics (61.74±0.9 and 62.0±1.9, respectively). Conclusions: No flowable resin composite group with interposing ceramics reached a DC similar to the control group.

Resumo em Inglês:

Abstract Aim : To demonstrate the feasibility of enabling trained acupuncturist as professionals able to detect oral lesions, with a role in the screening of oral cancer. Methods: This study was conducted in two phases. In the first, 11 acupuncturists were trained for visual detection of oral lesions and support content available on : <www.kankou.com.br>, especially developed for this study. They were evaluated at the end of training by a written exam. The inclusion criteria were to sign the consent form and to obtain a minimum of 90% of correct answers in the assessment. Four acupuncturists fulfilled both criteria and were included as study subjects. In the second phase, the subjects and the researcher (gold standard) examined 43 volunteer patients. The inclusion criterion for volunteers was just to sign the consent form. The volunteers' sample was established by saturation. Volunteers with changes deemed suspicious by the subjects were reexamined 15 days after the first examination. Results: First exam: mouth alterations were detected in 56% (n=24) of the volunteers. Among the alterations, 21% (n=5) were deemed suspicious by the subjects and 8% (n=2) by gold standard. Second exam: two mouth alterations remained suspicious and these volunteers were referred to the Dental Specialty Center for diagnosis and treatment. Compared to the gold standard, no injury remained undetected by the subjects. Conclusions: This study concluded for the feasibility of enabling trained acupuncturist to visually detect oral lesions and have a role in oral cancer screening.

Resumo em Inglês:

Abstract Aim: To isolate and identify in a Chilean population,Enterococcus spp. from root canals with persistent chronic apical periodontitis (CAP) and to investigate the potential correlation between the bacteria and the observed clinical features. Methods: Twenty patients with indication for endodontic retreatment due to persistent CAP were selected. Data from patient general health and dental clinical history were recorded. During retreatment, a microbial sample was obtained from the root canal and inoculated in a selectiveEnterococcus medium. Using bacterial cultivation methods, bacterial isolates belonging to the genusEnterococcus were identified. The relationship between the number of colony-forming units of Enterococcus spp. and patient clinical data was assessed statistically by the Pearson Chi square and Fisher exact tests. Finally, a Polymerase Chain Reaction (PCR) assay to determine the most prevalent species of Enterococcus spp. was conducted in the clinical samples, and the results were analyzed by a proportion comparison test. Results: Enterococcus spp. strains were isolated in 70% of the patients. Most of them (98.8%) accounted for Enterococcus faecalis and only 1.2% for Enterococcus faecium. A high frequency of E. faecalis was found in teeth with inadequate endodontic treatment or dental crown restorations. Conclusions: This study concluded that E. faecalis is prevalent in root canals with persistent CAP in a Chilean population. E. faecium as found in a single case with the poorest root canal filling. Further studies are still required to investigate the presence of other species, which may be linked to persistent chronic apical periodontitis.

Resumo em Inglês:

Abstract Aim: To evaluate the long-term post push-out bond strength to dentin, water sorption, solubility and swelling of conventional and self-adhesive dual-cure resin cements. Methods: Forty-eight bovine roots were prepared for fiber post cementation with RelyX ARC and RelyX U100. According to resin cement and storage time (24 h and 6 months), 4 groups were assessed using the push-out test. Water sorption and solubility were performed according to ISO 4049:2009. The swelling coefficient was obtained using cement disks of each material immersed in distilled water until the swelling equilibrium was reached. The mass of dry and swelled polymer and solvent density were used to calculate the coefficient. Statistical data analysis was performed using Student's t-test for water sorption, solubility and swelling coefficient and the Kruskal-Wallis and Dunn multiple comparison tests for push-out analysis with a significance level of 0.05. Results: The immediate bond strength was not significantly different between RelyX ARC (3.09 MPa) and RelyX U100 (3.78 MPa) (p>0.05). RelyX U100 showed higher (p<0.05) bond strength after six months of storage (9.60 MPa) than RelyX ARC (6.65 MPa). The water sorption and solubility values were not significantly different (p>0.05) between groups. The swelling coefficient of the RelyX U100 group was significantly higher than that of the RelyX ARC group (p<0.05). Conclusions: RelyX U100 resin cement showed a higher swelling coefficient than RelyX ARC, and the longitudinal push-out bond strength increased after six months. Clinical significance: The clinical longevity of restorative treatment in root-filled teeth is dependent on the long-term properties and behavior of the cement used for post luting. Results of this study suggest that the selfadhesive resin cement may be a reliable alternative.

Resumo em Inglês:

Abstract Aim : To assess the surface topography and chemical composition of three brands of as-received mini-implants (SIN(r), Morelli(r), and Conexao(r)). Methods: Twelve mini-implants of each brand were analyzed by scanning electron microscopy and energy dispersive X-ray (EDX). Results: There was no significant differences among SIN(r), Morelli(r), and Conexao(r) mini-implants comparing their surface topography by visualization of SEM micrographs and analysis of scores. The EDX analysis showed statistically significant difference among them for the amount of Ti, Al and V. Miniimplants SIN(r)presented also N and O in their composition. Conclusions: In conclusion, the miniimplants Morelli(r), SIN(r) and Conexao(r) presented Ti as main component of the alloy. Remaining components, such as Al and V, were also observed in all the analyzed brands, with differences among them. Only SIN(r)mini-implants presented N and O. As far as surface topography is concerned, there are no differences among the three brands of mini-implants.