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OBJECTIVE: This study aimed to investigate the effects of adding cholesteryl methacrylate (CM) monomer to experimental composite resins and evaluate its impact on polymerization shrinkage force (PSF), Knoop microhardness (KHN), sorption and solubility (SS), vulnerability to spontaneous oxidation (VOE), porosity (BES), viscosity (V), and cross-link density (CLD). CM was synthesized, mixed with varying proportions of Bis-GMA, 70 wt% filler particles, and 40 % TEGDMA. The groups tested were: CM0 (60 % Bis-GMA), CM6 (54 % Bis-GMA/6 % CM), CM12 (48 % Bis-GMA/12 % CM), CM18 (42 % Bis-GMA/18 % CM) and CM24 (36 % Bis-GMA/24 % CM). The PSF was evaluated using a universal testing machine. KHN was measured with a 50 g load for 30 s. SS was determined according to ISO 4049:2009. VOE was measured with a three-electrode system in an electrochemical cell. BES images were obtained using an electron microscope to assess porosity. Viscosity was measured through rheological analysis. CLD was estimated from hardness readings before and after ethanol storage. RESULTS: CM6 (0.34 N) and CM12 (0.34 N) exhibited the lowest PSF values compared to CM0 (0.91 N). For KHN, CM6 (32.03) and CM12 (31.03) had higher values than CM0 (25.83) and were similar to CM18 (29.39) and CM24 (28.64). SS showed no significant differences among the groups. VOE indicated low vulnerability across all groups. CM12 had greater porosity compared to CM0 in BES images. CM0 had the lowest viscosity among the groups. No differences in CLD were observed among CM0, CM12, CM18, and CM24 regarding softening effects. SIGNIFICANCE: Adding CM to Bis-GMA/TEGDMA composite resins can reduce polymerization shrinkage force and increase the initial Knoop microhardness without affecting the other properties studied.

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Background: To analyze through finite element analysis the stress distribution in peri-implant bone tissues, implants, and prosthetic components induced by the socket shield (SS) technique in comparison to other techniques used to treat tooth loss. Materials and Methods: A three-dimensional model of a superior central incisor crown supported by implant was modeled and three different placement conditions were simulated: SS - 2.0-mm-thick root dentin fragment positioned between the alveolar buccal wall and implant; heterologous bone graft (HBG) - bovine bone graft positioned the alveolar buccal wall and implant; and control (C) - implant fully placed in bone tissue of a healed alveolus. The model was restricted at the lateral surfaces of the bone tissue and the following loads were simulated: Both oblique (45°) loads of 100 N on the lingual surface of the crown (maximal habitual intercuspation) and 25.5 N on the incisal edge of the crown (tooth contact during mandibular protrusion) were simultaneously applied. Tensile stress, shear stress, compression, and displacement were analyzed in the cortical bone, trabecular bone, dentin root fragment, and bone graft; while equivalent von Mises stresses were quantified in the implant and prosthetic components. Results: Stress values of SS and HBG in the bone tissues were higher than C, while slight differences within models were observed for dentin root fragment, bone graft, implant, and prosthetic components. Conclusions: The SS technique presented the highest stress concentration in the peri-implant tissues.

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The aim of this study was to evaluate the effect of different die materials used in the indirect resin composite restorative technique on the fracture resistance and failure mode of restored molars and compare it with the direct resin composite restorative technique. Two flexible die silicone materials for dental models (Die Silicone - Voco and Scan die - Yller) and a type IV dental stone material (Fujirock EP - GC) were evaluated. Sixty third molars were selected and divided into four groups: indirect resin composite restoration - Die silicone (IRCR-DS); indirect resin composite restoration - Scan die (IRCR-SD); indirect resin composite restoration - Fujirock EP (IRCR-FR), and direct resin composite restoration (DRCR). Class II MOD cavities were prepared with 5 mm of buccolingual width and depth. The specimens were restored and subjected to an axial compression load until fracture, and the data were analyzed by one-way ANOVA and Tukey's HSD test (α=.05). The fracture mode was classified into restorable and unrestorable fractures. Fracture resistance values were influenced by the die material used for the IRCR fabrication and by the restorative technique (p<.001). Fracture resistance mean values and standard deviation were: IRCR-DS: 1835.5 ± 324.0 A; IRCR-SD: 1732.5 ± 384.1 AB; IRCR-FR: 1419.3 ± 318.8 BC; and DRCR: 1100.6 ± 224.9 C. Restorable fracture was more prevalent. IRCR with flexible die casts promoted higher fracture resistance and lower prevalence of unrestorable fractures.

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Abstract The aim of this study was to evaluate the effect of different die materials used in the indirect resin composite restorative technique on the fracture resistance and failure mode of restored molars and compare it with the direct resin composite restorative technique. Two flexible die silicone materials for dental models (Die Silicone - Voco and Scan die - Yller) and a type IV dental stone material (Fujirock EP - GC) were evaluated. Sixty third molars were selected and divided into four groups: indirect resin composite restoration - Die silicone (IRCR-DS); indirect resin composite restoration - Scan die (IRCR-SD); indirect resin composite restoration - Fujirock EP (IRCR-FR), and direct resin composite restoration (DRCR). Class II MOD cavities were prepared with 5 mm of buccolingual width and depth. The specimens were restored and subjected to an axial compression load until fracture, and the data were analyzed by one-way ANOVA and Tukey's HSD test (α=.05). The fracture mode was classified into restorable and unrestorable fractures. Fracture resistance values were influenced by the die material used for the IRCR fabrication and by the restorative technique (p<.001). Fracture resistance mean values and standard deviation were: IRCR-DS: 1835.5 ± 324.0 A; IRCR-SD: 1732.5 ± 384.1 AB; IRCR-FR: 1419.3 ± 318.8 BC; and DRCR: 1100.6 ± 224.9 C. Restorable fracture was more prevalent. IRCR with flexible die casts promoted higher fracture resistance and lower prevalence of unrestorable fractures.

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This study aimed to report the reasons for replacement of direct composite resin restorations in dental practices in Brazil. The study used a convenience sample of 213 dentists. A questionnaire was developed from previously validated instruments and sent electronically to prospective participants. The questions pertained to professional characteristics; criteria most frequently used in determining whether a direct composite resin restoration warranted replacement; and respondents' choice of treatment options (maintain, repair, or replace the restoration) in various clinical scenarios based on FDI World Dental Federation evaluation criteria, which are categorized into 3 groups: esthetic, functional, and biological properties. The descriptive statistical analysis was conducted using percentage frequencies, and associations between variables were tested using chi-square tests (α = 0.05). According to 47.9% of respondents, staining was the esthetic property that most often warranted replacement. For the functional property, 53.8% of respondents reported that fracture of material and retention was the most important factor indicating the need for replacement. For the clinical scenarios, 41.7% of respondents chose restoration replacement when evaluating esthetic properties, 59.8% when evaluating functional properties, and 64.4% when evaluating biological properties. Replacement, rather than maintenance or repair, was the most frequently reported clinical decision, and the dentists' professional profiles influenced treatment recommendations, with specialists exhibiting a slightly lower frequency of recommendations for replacement of direct composite resin restorations.

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PURPOSE: The aim of this systematic review was to evaluate the influence of zirconia and titanium as abutment materials on peri-implant soft tissue color. MATERIALS AND METHODS: The searched electronic databases included MEDLINE/PubMed, LILACS, Web of Science, Scopus, and LIVIVO. Two types of studies were included: randomized clinical trials (RCTs) and controlled clinical trials (CCTs) that compared zirconia (Zr) and titanium (Ti) abutments. The outcomes measured were as follows: implant crown esthetic index, visual analog scale, esthetic index, gingiva discoloration index-spectrophotometry, papilla index, recession index, and pink esthetic score. Two reviewers selected the records, assessed quality, and extracted data of included studies independently. RESULTS: A total of 323 patients enrolled in 13 studies were included in this analysis with 11 RCTs and 2 CCTs. Due to the wide variety of methodologies used, meta-analysis was only possible for RCTs that performed spectrophotometric analysis. The use of zirconia or titanium for implant abutments does not seem to be the principal factor for influencing peri-implant soft tissue color. The meta-analysis showed no difference between zirconia and titanium abutments. CONCLUSION: This study does not support any better advantage of the use of zirconia in comparison to the use of titanium related to peri-implant tissue color.

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OBJECTIVE: To evaluate facial profile changes promoted by polymethyl methacrylate (PMMA) cement graft to reduce excessive gingival display due to hyperactivity of the elevator muscles of the upper lip during smiling. METHODS: Eleven patients (all females, age range: 20 to 43 years) presenting gingival smile that were treated with PMMA cement grafts in a private clinic were selected for this retrospective study. Three angular and ten linear cephalometric facial profile measurements were performed preoperatively (baseline, T1) and at least 6 months postoperatively (T2). Differences between T1 and T2 were verified by Wilcoxon test, and the correlation between the thickness of the graft and facial profile changes was statistically evaluated by Spearman's Coefficient test. The significance level was set at p< 0.05. RESULTS: The nasolabial angle (p= 0.03) and the labial component of the nasolabial angle showed statistically significant differences (p= 0.04), with higher values in T2. No correlations were found between the graft thickness and the statistically significant facial profile changes (p> 0.05). CONCLUSIONS: The PMMA bone cement graft projected the upper lip forward, thereby increasing the nasolabial angle without affecting the nasal component. No correlations between the graft thickness and the facial profile changes were detected.

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ABSTRACT Objective To compare dimensions of natural maxillary anterior teeth and several denture teeth molds and also address differences between genders. Methods A single examiner with a digital caliper measured dental casts of 41 males and 55 females in order to determine CIW (central incisor width), CIL (central incisor length) and WS (width of anterior teeth on a straight line). In addition, WC (width of anterior teeth on a curve) was measured with a flexible ruler. These parameters were also observed on three denture teeth mold charts: Premium Pala, Vivodent and Trilux. The comparison between genders was analyzed using Student's t-test (?=.05), while absolute frequencies within several ranges were used to compare natural and denture teeth. Results CIW, CIL, WS and WC obtained from males were significantly higher than those found for females (p<0.05). CIW of nearly half of natural and denture teeth were within 8.0-8.5 mm. Almost half of natural teeth presented CIL values within 10.6-11 mm, while the highest frequency of denture teeth was observed within 9.6-10 mm. The majority of natural and denture teeth presented WS values within 42 to 49 mm. Only one denture teeth chart described WC values, which were mainly observed within 44-51 mm, while the majority of WC values obtained from natural teeth ranged from 48 to 55 mm. Conclusion Some commercially available denture teeth present dimensions not observed in natural teeth. Teeth dimensions in function of gender differences must be considered when selecting denture teeth.

RESUMO Objetivo Comparar as dimensões dos dentes anteriores superiores naturais e de diversos dentes artificiais para próteses e também abordar as diferenças entre os gêneros. Métodos Um único examinador mediu com um paquímetro digital dentes naturais de 41 homens e 55 mulheres para determinar CIW (largura do incisivo central), CIL (comprimento do incisivo central) e WS (largura dos dentes anteriores superiores em linha reta). Adicionalmente, CC (largura dos dentes anteriores em uma curva) foi aferida com uma régua flexível. Esses parâmetros também foram observados em três cartas moldes de dentes artificiais para prótese: Premium Pala, Vivodent e Trilux. A comparação entre os sexos foi analisada pelo teste t de Student (?=0,05), enquanto frequências absolutas foram usadas para comparar medidas dos dentes naturais e artificiais. Resultados CIW, CIL, WS e WC obtidos de homens foram significativamente maiores do que aqueles encontrados para mulheres (p<0,05). CIW de quase metade de dentes naturais e artificiais estavam entre 8,0-8,5 mm. Quase metade dos dentes naturais apresentaram valores CIL entre 10,6-11 mm, enquanto a maior frequência de dentes artificiais foi observada entre 9,6-10 mm. A maioria dos dentes naturais e artificiais apresentaram valores WS entre 42-49 mm. Apenas uma carta molde de dentes artificiais descreveu os valores de WC, que foram observados principalmente entre 44-51 mm, enquanto a maioria dos valores de WC obtidos em dentes naturais variaram de 48 a 55 mm. Conclusão Alguns dentes artificiais para próteses disponíveis comercialmente apresentam dimensões não observadas nos dentes naturais. As dimensões dos dentes em função das diferenças de gênero devem ser consideradas na seleção dos dentes artificiais.

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BACKGROUND: Multimode adhesives incorporate the versatility of adapting to various clinical situations by its capacity to be used in different protocols. This study aimed to evaluate the clinical behavior of composite resin direct restorations (Class I and II) performed with different universal dentin adhesive application protocols comparing adapted FDI and adapted USPHS criteria. METHODS: The current study is a randomized, double-blind, split-mouth, and convenience sample controlled clinical trial. The participants (age ≥ 18 years) had restorative need of Class I and/or II due to the presence of carious lesions and/or unsatisfactory restorations in at least three dental elements. Each participant received three application protocols for Scotchbond Universal adhesive (3M ESPE), one in each tooth to be restored: ER = etch-and-rinse + adhesive (n = 50); SEE = selective enamel etch + adhesive (n = 50) and SE = self-etch adhesive (n = 50). All teeth were restored in a similar way using Filtek™ Supreme composite resin (3M ESPE). Restorations were evaluated using the adapted FDI and adapted USPHS criteria, at baseline after 7 to 21 (12.02 ± 5.68) days (T1; n = 50 per group) and after 12 to 20 (15.8 ± 2.7) months (T2; n = 46 per group) by two previously calibrated evaluators (Kappa > 0.80). The statistical tests were performed between groups (Friedman), intragroup (Wilcoxon), and between the criteria considering acceptable and not acceptable restorations (McNemar), α = 0.05. RESULTS: A statistically significant difference was observed only for the property "superficial staining", between groups at T2 (p = 0.01) for ER (n = 13 with score 2 or more) and SEE (n = 3 with score 2 or more) and intragroup for ER (T1, n = 1 with score 2 or more; T2, n = 13 with score 2 or more, p = 0.001) and SE (T1, n = 0 with score 2 or more; T2, n = 8 with score 2 or more p = 0.007). For the other comparisons between groups, intragroup, and between the adapted FDI and adapted USPHS criteria, there were no statistically significant differences (p ≥ 0.05). CONCLUSIONS: It can be concluded that the different application protocols of the universal adhesive resulted in clinically "acceptable" restorations after 15.8 ± 2.7 months of follow-up. Adapted FDI and adapted USPHS criteria provided similar results to each other. TRIAL REGISTRATION: Number in Brazilian Registry of Clinical Trials (ReBEC): RBR-9p3hdp. Registered 24 May 2015.

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PURPOSE: To evaluate the equivalence of the volumes obtained using different anatomic references to measure the nasopharynx and oropharynx on cone-beam computed tomography (CBCT) scans. We hypothesized that no variations would be found in the nasopharynx and oropharynx dimensions when measured using different measurement methods. MATERIALS AND METHODS: A total of 40 CBCT scans of patients with skeletal Class I (age range, 20 to 50 years) were measured independently by 2 of us. The nasopharynx and oropharynx subregions were volumetrically measured using the adopted limits of 5 different measurement methods (3 for the nasopharynx and 2 for the oropharynx) and InVivoDental software, version 5.4 (Anatomage, San Jose, CA). The minimum area and the minimum area of localization were also evaluated. The intra- and interexaminer concordance for the measurements from the different methods were verified using the interclass correlation coefficient (ICC). The analysis of variance for repeated measures was used to compare the measurements from the 3 nasopharynx methods. The paired t test was used to compare the measurements from the 2 oropharynx methods. The statistical tests were performed at the 5% significance level using SPSS software, version 22.0 (IBM Corp, Armonk, NY). RESULTS: The intra- and interexaminer ICC values were greater than 0.8. We found a statistically significant difference in the volume measurements among the 3 nasopharynx methods (P = .001). However, no differences were found in the minimum area or minimum area of localization comparisons. Statistically significant differences were also observed for the volume, minimum area, and minimum area of localization between the 2 oropharynx methods (P = .001). CONCLUSIONS: Studies that have used different methods of measurement should not be directly compared. The different measurement methods used for nasopharynx and oropharynx evaluations should not be compared.

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Introduction: Physical violence became an important global problem in the last decades. This scenario is reflected in the increasing jurisprudence. In specific situations, perpetrators and victims of physical violence may inflict an especial patterned injury named bitemark. Knowing the case characteristics in lawsuits involving human bites and bitemarks is important to understand and encourage the role of Forensic Dentists as expert witness for bitemark analysis in Court. Objectives: The present study aimed to assess the jurisprudence to screen lawsuits that involve human bites and bitemarks in order to extract characteristics that could support research and practice of bitemark analysis. Material and methods: A systematic search was conducted in an open access jurisprudence system with the keywords "bite" and "bitemark". Full-texts of lawsuits were selected and underwent data extraction. Results: A total of 2488 lawsuits were detected, from which 1125 were eligible in the present study. The lawsuits dated between 1997 (n=13, 1.15%) and 2015 (n=202, 17.95%). Forensic expertises were performed in 641 (56.97%) lawsuits, but the identity of suspects was investigated only in 3 (0.26%) cases. Conclusions: An increasing trend of lawsuits involving human bites and bitemarks was observed. Forensic Dentists must be aware of the current bitemark scenario as well the limitations inherent to bitemark analysis to face casework in the field. The present study provides evidence to encourage major education in bitemark analysis.

Introdução: Ao longo dos anos a violência física vem se tornando um grande problema global que tem mostrado seu reflexo no aumento do número de jurisprudências envolvendo o assunto. Em alguns casos o agressor e a vítima podem produzir o mesmo padrão de injúria física, como a marca de mordida. Sabendo que as marcas de mordida e mordeduras humanas podem estar presentes em casos que envolvam ações judiciais é muito importante entender e incentivar a atuação do perito odontolegista para análise das marcas de mordida em processos judiciais. Objetivo: Analisar acórdãos que estivessem relacionados às marcas de mordidas e que pudessem subsidiar a rotina de marcas de mordida e a prática de análise dessas marcas. Materiais e métodos: Foi realizada uma busca sistematizada de acórdãos no Tribunal de Justiça de São Paulo utilizando as seguintes palavras-chave: mordida, dentada e mordedura. Apenas os acórdãos que estavam disponíveis em inteiro teor foram avaliados para captação dos dados que foram tabulados em uma planilha própria da pesquisa. Resultados: Foram detectados 2488 acórdãos, dos quais 1125 foram compatíveis com os critérios de elegibilidade, e datados entre os anos de 1997 a 2015. A análise pericial foi realizada em 641 (56,97%) casos, sendo o agressor identificado pela mordida em apenas 3 (0,26%) casos. Conclusão: Houve um significativo aumento em processos judiciais envolvendo marcas de mordida. Os odontolegistas devem estar cientes da ocorrência das marcas de mordida no cenário das agressões físicas bem como as limitações inerentes à análise dessas marcas frente ao campo de atuação dos peritos odontolegistas. O presente estudo fornece evidências para incentivar o aumento do estudo da análise das marcas de mordida.

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The aim of this study was to evaluate the contribution of cone-beam computed tomography (CBCT) in the decision of surgical management for bone lesions of the maxillofacial region. It is a retrospective cross-sectional observational study that includes a sample of panoramic radiography (PR) and CBCT from patients with some type of bone lesion in the maxillofacial region. PR and CBCT images were evaluated by three previously assessed examiners, specialists in oral and maxillofacial surgery. Each image was evaluated randomly, and a surgical procedure was suggested, initially in PR and then in CBCT. The obtained results were submitted to the McNemar test to evaluate the frequencies of changes in the surgical management between the first and the second evaluation in PR and CBCT, and intra-examiner and inter-examiner agreements were analyzed by the Cohen's kappa test. The level of significance was set at 5% (p < 0.05). Intra-examiner agreement increases when CBCT is used. Inter-examiner agreement was low, independently of the evaluated exam, which shows that the choice of treatment plan is examiner-dependent and not exam-dependent. CBCT increases the certainty of the professional in the evaluation of the bone lesions of the maxillofacial region; however, it does not change the indication of the treatment type.

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PURPOSE: To assess the correspondence of shades between try-in pastes and resin cements and their influence on the final color of veneers. MATERIALS AND METHODS: Bovine teeth (n = 140) were prepared and divided into 2 groups (a or b) according to ceramic veneer thickness (0.35 or 0.70 mm). Seventy teeth (n = 70) were distributed in 7 groups (groups 1 to 7a and groups 1 to 7b; n = 10). Try-in pastes and their corresponding resin cements were used according to the value: groups 1a and 1b (value -3); groups 2a and 2b (-2); groups 3a and 3b (-1); groups 4a and 4b (0); groups 5a and 5b (+1); groups 6a and 6b (+2); groups 7a and 7b (+3). Color measurements were performed with spectrophotometer, and the coordinates L* , a* , and b* were obtained. The final color change (ΔE) was calculated from these coordinates: ΔE0 (trial - substrate), ΔE1 (cementation - substrate), and ΔE2 (cementation - trial). The data were analyzed using the Kolmogorov-Smirnov test, the Wilcoxon test, or t-test for paired samples and repeated-measures ANOVA, post hoc Bonferroni, or the Friedman test (p < 0.05). RESULTS: The results indicated no statistically significant difference between the groups comparing ΔE0 and ΔE1 for 0.35 mm thickness laminate veneers, except for groups 2a and 5a. For 0.70 mm thickness laminate veneers, no statistically significant differences were observed between the groups comparing ΔE0 and ΔE1. ΔE2 values for 0.35 mm and 0.70 mm thickness laminate veneers ranged from 1.77 ± 0.81 to 4.99 ± 3.80 and from 1.01 ± 0.73 to 4.66 ± 2.96, respectively. CONCLUSIONS: Try-in pastes correspond with their respective resin cements for most colors investigated. The color of the resin cement may influence the final color of laminate veneers. Thickness of the ceramic was the most relevant variable for color change.

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ABSTRACT Cranioencephalic trauma which results in extensive edema and / or bruising usually requires surgical treatment through a greater withdrawal of the bone portion. Thus, the absence of bone tissue implies the lack of protection of the brain tissue or even compromises the esthetics especially when located in the frontal or frontoparietal region. The purpose of this case report is to describe a treatment option for head trauma, through the prefabricated part by obtaining the skull model. These bone faults can be reconstructed either by the direct method using polymethylmethacrylate directly on the defects or by means of pre-made pieces such as prototyping or from the skull model. Although other techniques have many good points, some show certain drawbacks, from storage conditions below abdominal fat, preheating due to the release of heat during the high polymerization reaction or the high cost when they are prototyped. The technique described in this work reports its simple performance, eliminating the risk of local heating, allows prior sterilization in autoclave, it is biocompatible, allows perfect anatomical recovery, easy placement, low cost, also highlighs the advantage of the bucomaxillofacial surgeon's performance due to the familiarization with the relevant head and neck procedures. Clinical and tomographic examination after 24 months of treatment showed stability of the polymethylmethacrylate plate, adhesions to the bone margins, and absence of tissue alterations.

RESUMO Os traumatismos cranioencefálicos que resultam em extensos edemas e ou hematomas normalmente, requerem tratamentos cirúrgicos por meio de uma retirada maior de porção óssea. Deste modo, a ausência do tecido ósseo implica na falta de proteção do tecido cerebral ou até mesmo comprometer a estética especialmente, quando localizadas na região frontal ou frontoparietal. O objetivo deste relato de caso é descrever uma opção de tratamento para os traumatismos cranioencefálicos, por meio da peça pré-fabricada mediante a obtenção do modelo do crânio. Estas falhas ósseas podem ser reconstruídas tanto pelo método direto utilizando o polimetilmetacrilato diretamente sobre as falhas ou por meio das peças pré-confeccionadas como a prototipagem ou a partir do modelo do crânio. Embora outras técnicas apresentem muitos pontos positivos, algumas mostram determinados inconvenientes, desde condição de armazenamento abaixo da gordura abdominal, aquecimento prévio devido a liberação de calor durante a reação de alto polimerização ou o alto custo quando são prototipadas. A técnica neste trabalho descrita relata sua facilidade de execução, elimina o risco do aquecimento local, permite a prévia esterilização em autoclave, é biocompatível, permite a perfeita recuperação anatômica, fácil colocação, baixo custo, ressaltando ainda a vantagem da atuação do cirurgião bucomaxilofacial devido sua familiarização com os procedimentos pertinentes a cabeça e pescoço. Em exame clínico e tomográfico após 24 meses do tratamento, observa-se estabilidade da placa de polimetilmetacrilato, aderências às margens ósseas, e ausência de alterações tissulares.

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Tooth loss promotes bone and gingival tissue remodeling, thus breaking the harmony between the residual ridge and natural teeth. This is critical in the anterior region of the mouth, and the integration of several dental specialties is often essential to successful rehabilitation with implants. This article describes a multidisciplinary approach to implant-supported oral rehabilitation in the maxillary anterior region, presenting a new technique for optimizing esthetics in implants. A 19-year-old woman was missing her central and lateral incisors and had 2 dental implants in the lateral incisor sites. The patient exhibited deficient thickness of the alveolar edge, loss of lip support, and absence of gingival architecture, and the implants were improperly placed. A multidisciplinary team created a correct emergence profile through a polymethyl methacrylate-based bone cement graft along with connective tissue grafts. This technique may be a useful therapeutic adjunct in dental implantology, showing good predictability and regular healing procedures.

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The anatomical characteristics of permanent maxillary canines were evaluated through visual examination, periapical radiography, and cone beam computed tomography (CBCT), and measurements obtained from the images and directly on the teeth were compared. Fifty extracted human maxillary canines were classified according to the side of the mouth. The direction of root curvature and location of the apical foramen were also verified. Periapical radiographs and CBCTs of the specimens were obtained. The number of root canals was verified. Tooth length and the mesiodistal and buccopalatal widths of the root were measured directly on the specimens as well as on the radiographs and CBCTs. Data were analyzed by chi-square testing and analysis of variance (α = 0.05). All teeth-26 (52%) from the right side of the dental arch and 24 (48%) from the left-had only 1 main canal each. The apical foramen was located exactly in the root apex in 34 teeth (68%). Root curvature toward the distal side was observed in the apical third in 23 teeth (46%). There were no statistically significant differences between the canines' arch side and either the foramen location (P = 0.104) or the root curvature (P = 0.215). No statistically significant differences were found in measurements of tooth length (P = 0.669), mesiodistal root width (P = 0.517), or buccopalatal root width (P = 0.672) obtained from specimens and images. Both CBCTs and periapical radiographs were reliable for determining the tooth length, mesiodistal root width, and buccopalatal root width of maxillary canines and produced statistically similar measurements.

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Background. The present study aimed to screen the knowledge and attitudes of dentists toward the use of informed consent forms prior to procedures involving operative dentistry. Methods. A research tool containing questions (questionnaire) regarding the use of informed consent forms was developed. The questionnaire consisted of seven questions structured to screen the current practice in operative dentistry towards the use of informed consent forms. Results. The questionnaires were distributed among 731 dentists, of which 179 returned them with answers. Sixty-seven dentists reported not using informed consent forms. The main reasons for not using informed consent forms were: having a complete dental record signed by the patient (67.2%) and having a good relation with patients (43.6%). The dentists who reported using informed consent forms revealed that they obtained them from other dentists and made their own modifications (35.9%). Few dentists revealed contacting lawyers (1.7%) and experts in legal dentistry (0.9%) for the development of their informed consent forms. Conclusion. A high number of dentists working in the field of operative dentistry behave according to the ethical standards in the clinical practice, becoming unprotected against ethical and legal actions.

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Introdução: O boxplot é um recurso gráfico usado regularmente na pesquisa científica para sumarizar e analisar dados quantitativos. Objetivo: Descrever didaticamente a estrutura, interpretação, construção, modificações e aplicações deste recurso visual. Resultados: O boxplot tradicional exibe medidas de tendência central não-paramétrica (mediana), de dispersão (quartis), forma de distribuição ou simetria da amostra (valores pontuais mínimo e máximo), valores atípicos (outliers) e extremos. Modificações podem ser incorporadas para possibilitar a inserção de parâmetros como média, desvio padrão e intervalo de confiança. As aplicações incluem análise exploratória dos dados, detecção de outliers e comparação entre grupos (equivalência). Conclusão: O boxplot é um recurso gráfico aperfeiçoado que cumpre com a análise exploratória e até mesmo inferencial dos dados e pode substituir o uso de tabelas em casos específicos.

Introduction: The boxplot is a graphics feature used regularly in this scientific research in various statistical software. Objective: To describe didactically the structure, interpretation, modifications and applications of this graphic feature. Results: The traditional boxplot displays the central trend data nonparametric (median), dispersion (quartiles), the form of distribution or symmetry (point maximum and minimum values) of the sample, and outlier. The boxplot has been modified with a view to inclusion of other properties such as the arithmetic mean and confidence interval. Applications can be compiled for exploratory data analysis, outlier detection, comparison between groups (equivalence) and multivariate data analysis. Conclusion: The boxplot is a graph feature that can replace the use of tables in specific cases.

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PURPOSE: To evaluate the effect of genioplasty on the size of the pharyngeal airway space (PAS) in a sample of patients without obstructive sleep apnea syndrome (OSAS) undergoing maxillomandibular advancement (MMA) surgery. MATERIALS AND METHODS: Lateral cephalometric radiographs of 52 patients who underwent orthognathic surgery for MMA were obtained before (T1) and after (T2) surgery. The radiographs were digitized and the anteroposterior dimensions of the PAS were measured at the nasopharynx, oropharynx, and hypopharynx levels. The sample was divided into 2 groups: MMA with genioplasty (n = 27; average age, 30.81 yr) and without genioplasty (n = 25; average age, 37.64 yr). Comparisons were made between T1 and T2 in patients with and without genioplasty. Horizontal and vertical changes of the maxilla, mandible, and chin were correlated to changes in the PAS. RESULTS: MMA resulted in an increased anteroposterior PAS at the 3 levels analyzed (P < .05), except in the hypopharynx, in cases without genioplasty (P = .141). When the groups with and without genioplasty were compared, there were no significant differences (P > .05) in the PAS. There was a statistically relevant correlation between horizontal mandibular change and the oropharynx (r = 0.484 and r = 0.509, respectively) and between vertical chin change and the hypopharynx (r = 0.434 and r = 0.455, respectively) for groups with and without genioplasty. There was a statistically relevant correlation between horizontal chin change and the hypopharynx (r = 0.586) for surgeries without genioplasty. CONCLUSION: Considering the limitations inherent to retrospective study designs, the results suggested that MMA surgery, with and without advancement genioplasty, can promote immediate gains to the PAS. A larger gain was possible in the hypopharynx for MMA with genioplasty. MMA without genioplasty could represent a greater gain in the nasopharynx and oropharynx. Further studies should evaluate functional parameters in patients with OSAS to measure the possible benefits of this increase in the PAS.

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OBJECTIVE:: This study evaluated the inflammatory responses of human dental pulp after the use of two bleaching techniques. MATERIAL AND METHODS:: Pulp samples were collected from human third molars extracted for orthodontic reasons and divided into three groups: control - no tooth bleaching (CG) (n=7); at-home bleaching with 15% carbamide peroxide (AH) (n = 10), and in-office bleaching with 38% hydrogen peroxide (IO) (n=12). Pulps were removed and stained with hematoxylin-eosin for microscopic analysis of inflammation intensity, collagen degradation, and pulp tissue organization. Immunohistochemistry was used to detect mast cells (tryptase+), blood vessels (CD31+), and macrophages (CD68+). Chi-square, Kruskal-Wallis, and Mann Whitney tests were used for statistical analysis. The level of significance was set at p<.05. RESULTS:: The inflammation intensity and the number of macrophages were significantly greater in IO than in AH and CG (p<0.05). The results of CD31+ (blood vessels per mm2) were similar in CG (61.39±20.03), AH (52.29±27.62), and IO (57.43±8.69) groups (p>0.05). No mast cells were found in the pulp samples analyzed. CONCLUSION:: In-office bleaching with 38% hydrogen peroxide resulted in more intense inflammation, higher macrophages migration, and greater pulp damage then at-home bleaching with 15% carbamide peroxide, however, these bleaching techniques did not induce migration of mast cells and increased the number of blood vessels.

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