RESUMO A similaridade entre o tecido da mama e o da glândula salivar está bem estabelecida. A porção das estruturas acinares e ductais destes órgãos são basicamente semelhantes. Estes aspectos, associados ao fato de que uma coexistência de carcinomas da mama e de glândula salivar, têm sido relatados em uma incidência maior do que a esperada. Guiaram estudos tentando determinar a importância dos receptores de estrógeno e progesterona em adenomas pleomórficos (AP). A neoplasia é mais freqüente nas glândulas salivares e exibe uma predileção para o sexo feminino. Recentemente a presença do receptor de estrógeno (RE) e do receptor de progesterona (RP) tem sido investigada no AP, entre outras neoplasias de glândula salivar, questionando-se a possibilidade da existência da dependência hormonal. A expressão dos receptores hormonais nos carcinomas de mama é importante para determinar o prognóstico e a probabilidade de responder à manipulação hormonal. Neoplasias que apresentam positividade para ambos os receptores, estrógeno e progesterona, exibem maior probabilidade de resposta à terapia anti-estrogênica do que as neoplasias que são negativas para estes receptores. Baseando-se na literatura científica pertinente, o presente trabalho se propõe a investigar a presença da proteína RE e da proteína RP em APs humanos, relacionando-os com a proliferação de linhagens celulares sob a influência destes hormônios. A técnica utilizada foi a imuno-histoquímica para a pesquisa dos RE e RP em 10 APs emblocados em parafina pertencentes ao arquivo do Serviço de Patologia Cirúrgica da FOUSP, e de duas linhagens de APs estabelecidas no mesmo serviço: uma derivada de um paciente do sexo masculino e a outra de um paciente do sexo feminino. No meio de cultivo onde subculturas destas células proliferavam foram diluídos 17-b-estradiol e progesterona. Através de contagens destas células em períodos pré-determinados (24 horas, 48 horas e 72 horas), pretendeu-se verificar a influência dos respectivos hormônios na multiplicação celular. Como controle positivo utilizou-se uma linhagem denominada T-47D, que foi largamente estudada na literatura. A T-47D é derivada de um carcinoma metastático de mama, reconhecidamente hormônio dependente. E como controle negativo, utilizou-se de uma linhagem de carcinoma epidermóide, denominada HN30. Encontrou-se positividade para o RE em 7 de 10 APs estudados (4 em homens e 3 em mulheres) e positividade para o RP em 8 Aps estudados (4 em mulheres e 4 em homens). Pela análise estatística, constatou-se que existe uma diferença significativa no índice proliferativo entre o controle e as células submetidas à ação do 17-b-estradiol e da progesterona. Para a linhagem derivada do paciente do sexo masculino houve diferença entre o controle e as células expostas ao 17-b-estradiol e a progesterona somente nas últimas 72 horas. Para a linhagem derivada do sexo feminino constatou-se uma diferença significativa entre o controle e as células sob a influência da progesterona, a partir de 48 horas de proliferação celular. A diferença significativa entre o controle e as células sob a ação do 17-b-estradiol ocorreu somente a partir das 72 horas, sugerindo que o AP poderia ser uma neoplasia influenciada pela ação hormonal. / SUMARY It is well established the similarity between mammary and salivary glands especially between the acinic and ductile structures. These aspects, associated to the fact of coexistence of breast carcinomas and of salivary gland tumors been described, leaded studies in attempt to determine the importance of the ERs and Pr in pleomorphic adenomas (PA), the most frequent salivary gland tumor and with predilection for the females. Lately, the presence of ERs and of the PRs has been investigated in PA and other salivary gland tumors pointing out their hormonal dependency. The expression of hormone receptors in breast carcinomas is crucial to determine a presence for both receptors. These tumors exhibit better response to anti-estrogenic therapy than the negative ones. Basing on the pertinent scientific literature, the present study proposes to investigate the presence of the RE and of the RP in humans PA and connecting them with cellular proliferation in vitro, under the influence of these hormones. Immunohistochemistry technique was used for the detection of RE and RP in paraffin embedded 10 PAs from the files of the Department of Oral Pathology, School of Dentistry, University of São Paulo, and two PA cell lines one from a male patient and other female. The culture midia was supplied with, 17-b-estradiol and progesterone. A growth curve was performed (24 hours, 48 hours and 72 hours) to verify the influence of the respective hormones in the cellular proliferation. As a positive control T-47-D cells derived from a hormone dependent metastatic breast carcinoma were used, and as negative control HN30 cells, derived from a tongue squamous cell carcinoma. 7 of 10 PAs were positive (4 in men and 3 in women) for RP and 8 of 8 PAs (4 in women and 4 in men) for RE. The statistical analysis verified a significant difference in the proliferative index between the control cells and the ones submitted to the action of the 17-b-estradiol and of the progesterone: for male derived lineage a difference was only observed in the last 72 hours. In the other hand, for the female derived lineage a significant difference was verified starting from 48 hours, suggesting that PA can be influenced by hormonal action.

As lesões ósseas são doenças raras, mas com um grande destaque, que afetam a região maxilofacial. Dentre elas podemos destacar as Lesões Centrais de Células Gigantes e as Lesões Fibro-Ósseas Benignas (Displasia Cemento-Ossificante, Fibroma Ossificante e Displasia Fibrosa). O presente estudo teve como objetivo descrever e analisar os dados encontrados nas fichas de encaminhamento clínico presentes no Serviço de Patologia Oral e Maxilofacial da Faculdade de Odontologia da Universidade de São Paulo. Foram avaliados 89.265 casos em um período que variou de 1950 até 2016, utilizando as categorias de gênero, idade, etnia, sintomatologia, hipótese diagnóstica e localização anatômica. Após as exclusões, os casos selecionados somavam 773 casos divididos em: 267 casos de Lesão Central de Células Gigantes, 231 casos de Displasia Cemento Ossificante, 142 casos de Fibroma Ossificante e 133 de Displasia Fibrosa. Os resultados do estudo estão de acordo com o que está descrito na literatura, exceto nos casos de Displasia Fibrosa que foi encontrado uma predileção maior sexo feminino do que o masculino, mesmo que a literatura expresse que não existe tal predileção. Já nos casos de Displasia Cemento-Ossificante, o presente estudo mostrou que a maior prevalência de idade é entre a 4ª e 5ª década de vida e não entre a 3ª e 4ª como encontrado na literatura. Os casos de Displasia Cemento-Ossificante, em relação à etnia dos pacientes, mostraram que a maioria dos pacientes encontrados pelos autores eram leucodermas e não melanodermas como relata a literatura. Os resultados mostraram que mesmo em um centro de referência como o Serviço de Patologia Oral da Faculdade de Odontologia da Universidade de São Paulo, as lesões ósseas são raras e alguns fatores como idade em pacientes com Displasia Fibrosa e Displasia Cemento-Ossificante e etnia em pacientes com Displasia Cemento-Ossificante não correspondem ao encontrado na literatura mundial. / Bone lesions are rare but important diseases that affect the maxillofacial region. Among them we can highlight the Central Giant Cells Lesion and the Benign Fibro-Osseous Lesions (Cemento-Osseous Dysplasia, Ossifying Fibroma and Fibrous Dysplasia). The objective of this study was to describe and analyze the data found in the clinical referral forms present at the Oral and Maxillofacial Pathology Service of the Faculty of Dentistry of the University of São Paulo. We evaluated 89.265 cases in a period ranging from 1950 to 2016, using the categories of gender, age, ethnicity, symptomatology, diagnostic hypothesis and anatomical location. After the exclusions, the selected cases totaled 773 cases divided into 267 cases of Central Giant Cell Lesion, 231 cases of Cemento-Osseous Dysplasia, 142 cases of Ossyfing Fibroma and 133 cases of Fibrous Dysplasia. The results of the study are in agreement with what is described in the literature, except in the cases of Fibrous Dysplasia that a predilection was found greater female than the male, even if the literature expresses that there is no such predilection. In the cases of Cemento-Osseous Dysplasia, the present study showed that the highest prevalence of age is between the 4th and 5th decade of life and not between the 3rd and 4th as found in the literature. The cases of Cemento-Osseous Dysplasia, in relation to the ethnicity of the patients, showed that the majority of the patients found by the authors were white and not black as reported in the literature. The results showed that even in a reference center such as the Oral Pathology Service of the Faculty of Dentistry of the University of São Paulo, bone lesions are rare and some factors such as age in patients with Fibrous Dysplasia and Cement-Ossificante Dysplasia and ethnicity in patients with Cement-Ossific Dysplasia do not correspond to that found in the world literature.

In vivo and in vitro degradation of resin-dentin interfaces can occur and accounts for poor clinical performance of adhesive dentin interfaces/restorations. Interfacial degradation results from several factors, to include, but not limited to: water sorption, hydrolysis of ester linkages of methacrylates resins, and activation of endogenous dentin matrix metalloproteinases (MMPs) in non-infiltrated collagen fibrils. Reduction of collagenolytic and gelatinolytic activity in dentin has been shown to be effective both in vivo and in vitro upon application of proteases inhibitors, such as chlorhexidine. This study compared the in vitro durability of resin-dentin bonds using microtensile testing over 12-month of water storage among five adhesive systems, including an experimental adhesive system, which had 2% chlorhexidine incorporated into the material. The results showed that all adhesive systems had a significant decrease in bond strength after 6 months, and that this reduction in bond strength was not significant different among the five adhesive systems studied. It is possible that chlorhexidine might have its inhibitory activity against MMPs lost or reduced due to chemical interaction with the adhesive system components. Also, to assess resin-dentin bonds degradation process, laboratorial studies use long-term water storage, which is labor-intense and time consuming process, therefore this study tested the possibility of accelerating the resin-dentin degradation process using water storage at 50° C. A significant reduction in microtensile bond strength occurred for specimens after 12-month storage at 50° C. The higher temperature may have increased the rate of water sorption and hydrolytic activity within the polymer network leading to adverse consequences to the interface.

The purpose of this study was to determine which type of bevel in a class IV dental composite restoration is the most esthetic and has the best blend to natural tooth structure via clinical and spectrophotometric evaluations. The null hypotheses were as follows: (1) there is no difference in visual evaluation rank scores among five groups of evaluators for each type of bevel; (2) there is no agreement in the visual evaluation rank scores of the seven groups of bevels among all evaluators or within each group of evaluators; (3) there is no difference in the lightness values among seven types of bevels at each of eight measurement points or for the whole tooth as measured by a spectrophotometer; and (4) there is no correlation between the visual evaluation and the spectrophotometric evaluation. The class IV samples were made via CAD/CAM milling for standardization. There were seven groups: negative control (no bevel); short (1mm) and straight bevel; short (1mm) and scalloped bevel; long (2mm) and straight bevel; long (2mm) and scalloped bevel; infinite (3+mm) and straight bevel; and infinite (3+mm) and scalloped bevel. The fractures were restored with the same type of dental composite via a digitally designed mold fabricated with a 3D printer. Once completed, the samples were randomized and evaluated visually by 91 people in five groups (faculty, graduate residents, pre-doctoral dental students, assistants/hygienists, and auxiliary staff). Evaluators placed the samples in the order they deemed least to most esthetic within a lightbox set to CIE Standard Illumination D65. After the visual evaluation, the lightness (L*) values were measured optically with a reflectance spectrophotometer at eight points on each of the seven bevel groups, as well as on an un-prepared typodont tooth used for reference. One-way ANOVA on ranked data with the post-hoc Bonferroni test was conducted to detect a significant difference in median rating score among five groups of evaluators, and Kendall’s W was used to evaluate an agreement among multiple raters. One-way ANOVA with the post-hoc Tukey’s HSD was used to find a significant difference in mean lightness values among seven types of bevels. Dunnett’s test was used to compare the reference group with each of the seven bevel groups when evaluating the lightness values. Pearson Correlation test along with the simple linear regression analysis were used to determine whether a significant relationship existed between visual evaluation scores and lightness values. The groups were ranked from least to most esthetic as follows: no bevel, short and straight bevel, short and scalloped bevel, long and straight bevel, long and scalloped bevel, infinite and straight bevel, and infinite and scalloped bevel by the 91 evaluators and Kendall’s W was 0.80 (strong agreement). Moreover, no significant difference in rating scores was found among the five groups of evaluators regarding each type of bevel (p>0.05). The overall mean lightness values observed in groups 1-3 were significantly higher than those in groups 6 and 7 (P< 0.05), but no significant difference was noted among groups 1-5 or among groups 4-7. As the lightness values measured by the spectrophotometer decreased, the overall visual evaluation score increased. The Pearson Correlation Coefficient of -0.89 indicated there was a strong negative correlation between the two variables (p=0.0066). Linear regression analysis revealed that the predictor of lightness was significant (strong negative correlation, R-square 0.99, p< 0.0001). The first null hypothesis was accepted and the second, third, and fourth were rejected. There was no difference in median visual evaluation rank scores among five groups of evaluators for each type of bevel, however, there was agreement in the ranked order as the findings of this study indicated that infinite and scalloped bevel was the most preferred and no bevel was the least preferred via a strong agreement the evaluators. There was a significant difference in lightness values among the seven bevel groups; the shorter bevels had higher L* values that were closer to the L* values of the reference tooth while the longer bevels had lower L* values. The correlation data showed that placing a longer bevel (3+mm) allowed for a more gradual transition and better blending capabilities between the tooth structure and dental composite. The overall conclusion from this study was the longer the bevel, the more gradual the change in Lightness (L*), which correlated to the more esthetic restoration, as determined by the evaluators.

Current hydrophilic resin adhesives undergo hydrolytic degradation and show a decrease in bond strength over time. Nanoleakage and ultrastructure studies suggest that inadequately infiltrated collagen leads to enzymatic degradation and resin-dentin bond failure. Adequate degree of conversion (DC) of resin adhesives is also critical to resin-dentin bond strength and durability. The long-term goal of this dissertation is the realization of durable resin-dentin bond. It is hypothesized that ethanol-wet bonding technique (EW) may effectively facilitate the infiltration of hydrophobic monomers into hydrophilic acid-etched dentin by maintaining interfibrillar spacing, stiffening collagen matrix, and improving adhesive resin-demineralized dentin matrix miscibility. Chlorhexidine (CHX), Matrix Metalloproteinase-inhibitor (MMP-inhibitor), should further preserve collagen integrity and resin-dentin bond strength. Moreover, efficient photoinitiator systems that broaden light absorptivity and provide more reactive radicals may enhance polymerization. In this dissertation, a clinically-relevant EW protocol, 3×15s absolute ethanol rinsing, provided significantly higher microtensile bond strength (πTBS) of a hydrophobic resin (70%BisGMA/30%TEGDMA) to dentin as compared to water-wet bonding (WW). All groups showed no significant drop of πTBS after 1-year storage except EW without CHX application, showing marginally significant reduction in πTBS (p=0.0558) suggesting MMP-inhibition by CHX in EW. These results were consistent with subsequent experiments. EW maintained interfibrillar width and hybrid layer thickness for resin infiltration and retention. Monomer molar concentration across the hybrid layer was significantly higher in EW than WW. An application of 2% CHX diacetate further preserved collagen banding in EW. WW showed more generalized spotted nanoleakage, while EW presented localized reticular nanoleakage. The use of Irgacure 819 (BAPO) alone and in combination with benzoyl peroxide (BPO) or camphorquinone (CQ) increased DC of hydrophobic and hydrophilic resins over resins containing the CQ/amine (4E) control. Only BAPO and BAPO/BPO demonstrated significantly higher immediate shear bond strength than CQ/4E. Within the limitations of these studies, EW improved resin-dentin bond durability by maintaining collagen interfibrillar spaces for efficient infiltration of a hydrophobic BisGMA/TEGDMA resin resulting in significantly higher πTBS and monomer molar concentrations with less nanoleakage distribution within the hybrid layer than WW. CHX further maintained collagen integrity and πTBS in EW. BAPO is a potential alternative photoinitiator of dental resins.

The precise role that genes play in early craniofacial development and postnatal craniofacial growth are essential to understand dento-facial development overall. However, genotype-phenotype correlations between genetic variation of early craniofacial genes and adult craniofacial phenotypes is poorly understood. Thus, this thesis focused on identifying the genetic etiology underlying phenotypic variations present in malocclusion conditions. First, we performed genotype-phenotype association analyses between common variants in 82 craniofacial genes and phenotypic variations extracted from 2D and 3D pre-treatment dental records of individuals with malocclusion. This effort identified that variant rs2189000 upstream of TWIST1 is highly associated with mandibular body length and inclination and cranial base angulations which can lead to malocclusion. Next, via cell based functional assays, we discovered that rs2189000 disrupts a PITX2 binding site and also showed the direct regulation of TWIST1 expression by the PITX2 gene. Finally, we identified abnormal craniofacial phenotypes and malocclusion in Twist1 deleted mice including asymmetric snouts, domed cranial vaults, and changes in size and inclination of the cranial base, palate and mandible resulting in malocclusion and resembling the human phenotypes observed. Also, premature calcification of calvarial sutures and cranial base synchondroses were also observed in the mutant mice indicating a possible biological mechanism for the abnormal phenotypes detected. These results confirm that TWIST1 is an important regulator of postnatal growth and that genetic variation in TWIST1 can result in malocclusion. The continued identification of genetic etiological factors and their role in craniofacial growth will impact treatment and prevention of malocclusion and other craniofacial conditions

Objective: The purpose of this study was to evaluate the accuracy of surgical guides for dental implant placement fabricated by additive and subtractive techniques. Methods: A standardized mandible model (BoneModels, Castellón, Spain) was duplicated and the proposed implant position was performed from a diagnostic wax-up. An implant was placed in the printed model as a reference. Cone beam computed tomography (CBCT) was made with the radiographic surgical guide to design a surgical guide on BlueSky Plan 4 software. The .stl file of the surgical guide was exported and fabricated by two different techniques: additive (3D printing) and subtractive (milling). Fifteen surgical guides per group were used to place implants in the printed models. The angular deviations, differences in depth, coronal and apical deviations were measured using GeoMagic Control X software. Results were analyzed by Wilcoxon-Mann-Whitney (Wilcoxon Rank Sum) test and PERMANOVA (Permutational Multivariate Analysis of Variance). Intraclass correlation was used to analyze the reproducibility. A 0.05 level of significance was used, with Bonferroni multiple adjustment as needed. Results: There were no significant differences in accuracy of implant placement using additive technique vs subtractive techniques. The mean angular deviations between planned and actual position of implant in mesio-distal cross-section were 0.780±0.803 degrees for printed group and 0.772±0.724 degrees for the milled group. The analogous results in bucco-lingual cross-section were 1.601±1.223 degrees in in printed group and 1.767±0.762 degrees in the milled group. The differences in depth (mm) were measured in four aspects including mesial, distal, buccal and lingual. The mean differences in depth in the group that using printed surgical guides were 0.373±0.285 mm, 0.325±0.230 mm, 0.240±0.228 mm, and 0.247±0.168 mm in those 4 aspects, respectively. The mean differences in depth in the group that using milled surgical guides were 0.511±0.326 mm, 0.396±0.316 mm, 0.215±0.230 mm, and 0.230±0.122 mm in those four aspects, respectively. The mean coronal deviation showed 0.32 mm in the printed group and 0.27 mm in the milled group. For the apical deviation, the results of this study showed mean apical deviation 0.84 mm in the printed group and 0.80 mm in the milled group. Conclusions: No statistically significant difference was identified between the position of implant placed using surgical guide fabricated by the additive technique (3D printing) vs surgical guides fabricated by subtractive technique (milling). The 3D-printed surgical guide could be an alternative for guided-implant surgery with the benefits of high accuracy, ease of fabrication and reduction of laboratory time and materials, thereby increasing cost-effectiveness.

Introduction: The use of CBCT to visualize the relationship between the inferior alveolar canal and the mandibular third molar roots continues to grow as it is becoming the standard of care. It becomes important to understand the impact that luminance, one of the factors that affects the viewing conditions of digital images, has on appropriately assessing the third molar-canal relationship. To date, no study has assessed the impact of luminance on visualizing anatomic structures on CBCT. The aim of this study is to determine if there is a difference in the ability to appropriately assess the root development and the third molar-canal relationship on a medical grade monitor with four different luminance settings on CBCT. Materials and methods: 285 scans were randomized and evaluated by three calibrated and masked evaluators. The evaluations were completed on a Barco MDNC-3321 Nio Color 3MP monitor (Kortrijk, Belgium) monitor at four different luminance settings; 200 cd/m2, 300 cd/m2, 400 cd/m2, and 500 cd/m2. The gold standard was established by two board-certified oral and maxillofacial radiologists. All evaluations were performed in a controlled subdued environment lighting of less than 15 lux. There was a washout period of at least one week between each of the four evaluations by an observer. Results: The accuracy of two of the three evaluators was substantial to almost perfect independent of luminance. None of these assessments showed any statistical significance (P = 0.05). The accuracy of one evaluator was moderate to almost perfect for all evaluations with one assessment of one canal showing statistical significance (P = 0.05). Conclusion: There is no difference in the ability to appropriately assess the third molar canal relationship or the root development of third molars on a medical grade monitor at luminance settings between the range of 200 cd/m2 and 500 cd/m2 when viewed in a dimly lit room.

No description available.

POTENTIAL ANTIMICROBIAL METHODS FOR PROVISIONALIZING TEETH AFTER ENDODONTIC TREATMENT By Laura T. Garden, DDS A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University. Virginia Commonwealth University, 2018 Thesis Advisor: Garry Myers, DDS Department of Endodontics Objective:To evaluate the effectiveness of a Chlorhexidine soaked cotton pellet on bacterial leakage. Methods: Fifty-one extracted teeth, including six controls, were instrumented, obturated, and sealed with either a cotton pellet (CP), 2% Chlorhexidine soaked cotton pellet (CHX), or a Permaflo orifice barrier (OB). Each root was suspended between two chambers: the coronal chamber inoculated with brain heart infusion broth and colony-forming units of Enterococcus faecalis, the apical chamber with brain heart infusion broth and phenol red. The latter was checked daily for turbidity, indicating bacterial leakage. Results: All open and closed control groups had leaked by day 7. The average CP tooth survived for 13.1 days whereas the CHX and OB teeth leaked by an average of 5.8 days. Conclusion:There is insufficient evidence to support the use of a Chlorhexidine soaked cotton pellet. The results were not as expected and the study design should be re-evaluated.