Reabilitação oral com próteses parciais removíveis após restabelecimento de dimensão vertical de oclusão e tratamento multidisciplinar: relato de caso / Oral rehabilitation with removable partial dentures after restoration of the vertical dimension of occlusion and multidisciplinary treatment: case report

As próteses parciais removíveis (PPRs) são uma alternativa de tratamento viável na prática clínica para reabilitar arcos parcialmente desdentados. Entretanto, o planejamento dessas próteses e preparo bucal prévio são frequentemente negligenciados. O presente artigo tem como objetivo relatar o caso clínico de uma reabilitação oral com PPRs superior e inferior após abordagem multidisciplinar, de modo a enfatizar as fases de um planejamento criterioso e de preparo prévio dos dentes pilares, visando o sucesso e a longevidade da reabilitação. Paciente do sexo masculino de 57 anos de idade compareceu à clínica da Faculdade de Odontologia de Bauru, Universidade de São Paulo, queixando-se da estética de seu sorriso e de algumas ausências dentárias. O indivíduo utilizava uma PPR provisória inferior insatisfatória e apresentava perda de dimensão vertical de oclusão (DVO). Após o exame clínico, radiográfico e estudo do caso em articulador semi-ajustável, realizou-se o planejamento com abordagens restauradoras, endodônticas, periodontais e protéticas. Após tratamento periodontal, foi realizada endodontia dos elementos 12, 15 e 47, confecção de núcleos e coroas nos dentes 12 e 15, restauração a nível gengival para apoio residual no dente 47, restaurações nos dentes 11, 13, 22, 24 e 44 e, por fim, a confecção das PPRs superior e inferior. A abordagem multidisciplinar utilizada neste caso clínico viabilizou o restabelecimento da DVO e possibilitou o sucesso da reabilitação protética(AU)

Removable partial dentures (RPDs) are a viable treatment alternative in clinical practice to rehabilitate partially edentulous arches. However, the planning of these dentures and prior oral preparation are often neglected. This article aims to report the clinical case of an oral rehabilitation with upper and lower RPDs after a multidisciplinary approach, to emphasize the phases of careful planning and prior preparation of the abutment teeth, aiming at the success and longevity of the rehabilitation. A 57-year-old male patient came to the clinic of the Bauru School of Dentistry, University of São Paulo, complaining about the esthetics of his smile and some missing teeth. The subject was using an unsatisfactory lower provisional prosthesis and had a loss of vertical dimension of occlusion (OVD). After the clinical and radiographic examination and the case study in a semi-adjustable articulator, planning was carried out with restorative, endodontic, periodontal and prosthetic approaches. After periodontal treatment, endodontics were performed on elements 12, 15 and 47, creation of cores and crowns on teeth 12 and 15, restoration at the gingival level for residual support on tooth 47, restorations on teeth 11, 13, 22, 24 and 44 and, finally, the making of the upper and lower PPRs. The multidisciplinary approach used in this clinical case enabled the restoration of the OVD and enabled the success of the oral rehabilitation(AU)

A clinical application study of digital manufacturing simple intraoral Gothic arch-tracing device in determining the centric relation of complete dentures / 北京大学学报(医学版)

OBJECTIVE@#To verify the consistency between the digital manufacturing simple intraoral Gothic arch-tracing device and the traditional intraoral Gothic arch-tracing device in determining the centric relation of complete dentures restoration.@*METHODS@#Ten outpatients with edentulous jaws were selec-ted, and the centric relation of the patients was determined by digital manufacturing of simple intraoral Gothic arch-tracing device (T1) and traditional intraoral Gothic arch-tracing device (T2); the difference of clinical operation time between the two methods was recorded; the upper and lower edentulous jaw plaster models were scanned with two kinds of centric relation, the Standard Triangle Language (STL) files imported into Geomagic studio software to apply the best fitting of multiple points of the both upper jaw models, the fitted STL files imported into the 3 shape viewer software, and the maximum position deviations of the vertical, labial (buccal) and lingual directions of the mandibular midline area and molar areas in T1 and T2 groups measured. During the clinical complete dentures try-in, we observed whether there was midline deviation in the mouth of T1 group and T2 group, and whether the occlusion of posterior teeth was stable or not.@*RESULTS@#The mean time spent on determining the centric relation of T1 and T2 groups was (41.90±2.64) min, (57.50±2.37) min respectively. Paired t test was conducted in the two groups, P < 0.01 with significant statistical difference; The mean maximum position deviation between T1 group and T2 group of the midline mandibular region in labial lingual direction was (0.32±0.14) mm, that was (0.40±0.23) mm in vertical direction; the mean maximum position deviation of molar area in buccal lingual direction was (0.35±0.23) mm and that was (0.33±0.20) mm in vertical direction. In the vertical and horizontal directions, the maximum position deviation of mandibles between group T1 and group T2 was controlled within 0.5 mm. In the process of clinical complete dentures try-in, there was no deviation from the center line of dentures. There was not warping, swinging and other poor stability phenomena in T1 and T2 groups.@*CONCLUSION@#The digital manufacturing of simple intraoral Gothic arch-tracing device can be used to determine the centric relation of complete dentures, which can not only save time of clinical operation, but also ensure the accuracy of the centric relation.

The challenges of reconstruction and rehabilitation of atrophic jaw with an autogenous graft from skull cap ­ a case report / Os desafios da reconstrução e reabilitação de mandíbula atrófica com enxerto autógeno de calota craniana ­ relato de caso

Introduction: One of the challenges of maxillofacial surgery is the rehabilitation of patients with severe bone loss, using implant-supported prostheses. This challenge is based on the small remaining bone structure, and on the need to reconstruct the structure for the rehabilitation with autogenous or exogenous grafts. Case report: We report the case of a patient with severe maxillary atrophy, where a skullcap graft was performed associated with implant placement and prosthetic completion 14 months after the start of treatment. Final considerations: We demonstrate clinical safety for the use of extraoral grafts without complications, representing a good alternative treatment for this group of patients.

Introdução: um dos desafios da cirurgia bucomaxilofacial é a reabilitação de pacientes com perda óssea severa, utilizando próteses implantossuportadas. Este desafio baseia-se na pequena estrutura óssea remanescente e na necessidade de reconstrução da estrutura para a reabilitação com enxertos autógenos ou exógenos. Relato de caso: Relatamos o caso de um paciente com atrofia maxilar grave, onde foi realizado enxerto de calota craniana associado à instalação de implante, com finalização protética 14 meses após o início do tratamento. Consideracoes finais: Demonstramos segurança clínica para o uso de enxertos extrabucais sem complicações, representando uma boa alternativa de tratamento para este grupo de pacientes.

Risk analysis and preventive strategies of implant placement in patients with hypertension / 中华口腔医学杂志

Recently, among the edentulous patients who undergo dental implants, the proportion of hypertensive patients remains high, which poses a greater challenge for clinicians to operate and to maintain the therapeutic effect. The present review comprehensively summarized clinical researches about the adverse effects on dental implants, outlined molecular mechanisms of the positive effects of various antihypertensive drugs on bone metabolism, and proposed that clinicians should select preventive strategies during preoperative and intraoperative procedures according to the blood pressure of patients with hypertension.

Application evaluation of prefabricated rigid connecting bar in implants immediate impression preparation of edentulous jaw / 北京大学学报(医学版)

OBJECTIVE@#To compare the operation complexity and accuracy of traditional splint impression technique and impression technique with prefabricated rigid connecting bar system for full-arch implants-supported fixed protheses in vitro.@*METHODS@#Standard mandibular edentulous model with six implant analogs was prepared. The implants were placed at the bone level and multiunit abutments screwed into the implants. Two impression techniques were performed: the traditional splint impression technique was used in the control group, and the rigid connecting bar system was used in the test group. In the control group, impression copings were screwed into the multiunit abutments and connected with autopolymerizing acrylic resin. Open tray impression was fabricated with custom tray and polyether. In the test group, cylinders were screwed into the multiunit abutments. Prefabricated rigid bars with suitable length were selected and connected to the cylinders with small amount of autopolymerizing acrylic resin, and open tray impression was obtained. Impression procedures were repeated 6 times in each group. The working time of the two impression methods were recorded and compared. Analogs were screws into the impressions and gypsum casts were poured. The gypsum casts and the standard model were transferred to stereolithography (STL) files with model scanner. Comparative analysis of the STL files of the gypsum casts and the standard model was carried out and the root mean square (RMS) error value of the gypsum casts of the control and test groups compared with the standard model was recorded. The trueness of the two impression techniques was compared.@*RESULTS@#The work time in the test group was significantly lower than that in the control group and the difference was statistically significant [(984.5±63.3) s vs. (1 478.3±156.2) s, P < 0.05]. Compared with the standard model, the RMS error value of the implant abutments in the test group was (16.9±5.5) μm. The RMS value in the control group was (20.2±8.0) μm. The difference between the two groups was not significant (P>0.05).@*CONCLUSION@#The prefabricated rigid connecting bar can save the chair-side work time in implants immediate loading of edentulous jaw and simplify the impression process. The impression accuracy is not significantly different from the traditional impression technology. The impression technique with prefabricated rigid connecting bar system is worthy of clinical application.

Efeitos da inibição do receptor 1 de cisteinil leucotrieno e da enzima 5-LO sobre o processo de osseointegração / Effects of inhibition of cysteinyl leukotriene receptor 1 and 5-LO enzyme on the osseointegration process

O presente estudo teve por objetivo avaliar os efeitos da inibição do receptor 1 de cisteinil leucotrieno (CisLT1R) e da enzima 5-lipoxigenase (5-LO) sobre o processo de reparo peri-implantar oral em camundongos. Para tanto, um total de 63 camundongos machos da linhagem 129/Sv foram utilizados, com idades variando de 12 a 14 semanas, sendo 42 animais WT (do inglês Wild Type) e 21 animais geneticamente modificados (knockout-KO) para a enzima 5-LO (5-LOKO), a fim de comporem os seguintes grupos: Controle/WT, MTK/WT e 5-LOKO. Todos os animais foram submetidos ao procedimento cirúrgico para instalação de um micro parafuso de titânio (liga Ti-6Al-4V) na região edêntula da maxila, imediatamente à frente do primeiro molar esquerdo. Previamente ao procedimento cirúrgico, os animais do grupo MTK/WT foram medicados 2 mg/Kg/dia de montelucaste (MTK), via oral, em volume de 10ul, iniciando um dia antes do procedimento e continuando até o final dos períodos experimentais, fixados aos 7, 14 e 30 dias pós-operatórios. Os animais dos grupos Controle/WT e 5-LOKO receberam 10ul de solução fisiológica 0,9%, seguindo o mesmo protocolo dos animais MTK/WT. Completados os períodos, os animais foram submetidos à eutanásia para a coleta das amostras e subsequente processamento para análises histológicas e imunohistoquímicas para avaliação do processo de reparo peri-implantar. Após a obtenção dos dados quantitativos, os mesmos foram submetidos a tratamento estatístico considerando o nível de significância de 5% (p< 0,05). Os animais dos grupos MTK/WT e 5-LOKO apresentaram formação precoce de tecido ósseo ao redor dos implantes, maior número de células COX-2+ e menor de células TRAP+, quando comparados com animais do grupo Controle/WT. Concluiu-se que, a inibição do CisLT1R pelo MTK, bem como a ausência do gene para a 5-LO aceleraram o processo de reparação óssea peri-implantar oral no presente modelo experimental(AU)

The present study aimed to evaluate the effects of inhibition of cysteinyl leukotriene receptor 1 (CisLT1R) and 5-lipoxygenase enzyme (5-LO) on the process of oral periimplant repair in mice. For this purpose, a total of 63 male mice of the 129/Sv strain were used, with ages ranging from 12 to 14 weeks, of which 42 WT (Wild Type) and 21 genetically modified (knockout-KO) animals for the 5-LO enzyme (5-LOKO), in order to compose the following groups: Control/WT, MTK/WT and 5-LOKO. All animals were submitted to a surgical procedure to install a titanium micro screw (Ti6Al-4V alloy) in the edentulous region of the maxilla, immediately in front of the first left molar. Previous to the surgical procedure, the animals in the MTK/WT group were medicated 2 mg/Kg/day of montelukast (MTK), orally, in a 10ul volume, starting one day before the procedure and continuing until the end of the experimental periods, set at 7, 14 and 30 postoperative days. The animals in the Control/WT and 5-LOKO groups received 10ul of 0.9% saline solution, following the same protocol as the MTK/WT animals. After the periods were completed, the animals were euthanized for sample collection and subsequent processing for histological and immunohistochemical analysis to evaluate the peri-implant repair process. After obtaining the quantitative data, they were submitted to statistical treatment considering a significance level of 5% (p< 0.05). Animals in the MTK/WT and 5-LOKO groups showed early bone tissue formation around the implants, higher numbers of COX-2+ cells and fewer TRAP+ cells, when compared to animals in the Control/WT group. It was concluded that, the inhibition of CisLT1R by MTK as well as the absence of the gene for 5-LO accelerated the process of oral peri-implant bone repair in the present experimental model(AU)

Análise da concavidade lingual da mandíbula por meio de tomografia computadorizada de feixe cônico: estudo retrospectivo transversal / Lingual analysis of the mandible by means of a cone-beam computed tomography study by means of a cross-sectional retrospective lingual study

O objetivo deste estudo é analisar e correlacionar características anatômicas da mandíbula posterior (presença e grau de inclinação da concavidade lingual, altura e espessura óssea) de mandíbulas edêntulas por meio de tomografias computadorizadas de feixe cônico. Material e Método: Foram selecionados cortes tomográficos transversais das hemimandíbulas, posteriores ao forame mentual 5, 10 e 15mm. Foram analisadas espessura óssea 2mm acima do canal alveolar inferior (Espessura A) e 2mm abaixo da crista alveolar (Espessura B); altura mandibular, angulação e profundidade da concavidade lingual nos gêneros. Além disso a hemimandíbula foi classificada de acordo com seu formato em U, C, P. Resultados: No corte de 10 mm a média de Espessura A foi de 11,2 ± 1,8 mm (F) e 10,5 ± 2,1 (M) (P = 0,057); a média de Espessura B foi 8,8 ± 2,9 mm (F) e 9,6 ± 2,1 mm (M)(P = 0,057); a Altura média foi de 12,7 ± 2,7 mm (F) e 15,5 ± 4,1 mm (M); a média de Ângulos da concavidade lingual foi de 64,2 ± 19,2° (F) e 66,3 ± 29,0° (M) (P = 0,006); a Profundidade da concavidade lingual foi de 3,0 ± 2,0 mm (F) e 6,8 ± 15,8 mm (M) (P = 0,033). O formato C foi o mais comum (51,9%) seguido do formato U (25%) e P (23,0%)(P = 0,001). Na correlação de cortes 5, 10 e 15 mm, a Espessura B aumentou significantemente para posterior nos formatos U e C (P=0,933). Conclusão: a concavidade lingual esteve presente na amostra estudada em 25% das tomografias. A profundidade da concavidade lingual foi maior no gênero masculino. Espessura e Altura de mandíbula posterior não variam de acordo com o gênero(AU)

The objective is to analyze and correlate the anatomical characteristics of the posterior (presence and degree of inclination of the height and bone thickness) of the analyzed mandibles through the study of computerized studies of conical height. Material and Method: Transverse tomographic sections of the hemimandibles were selected, posterior to the mental foramen at 5, 10 and 15 mm. Bone thickness was 2mm above the inferior alveolar canal (thickness A) and 2mm below the alveolar crest (thickness B); mandibular height, angulation and depth of the lingual concavity in the genera. In addition, the hemimandible was classified into U, C, P. Results: In the 10 mm section, the mean thickness A was 11.2 ± 1.8 mm (F) and 10.5 ± 2.1 (M) (P = 0.057); mean thickness B was 8.8 ± 2.9 mm (F) and 9.6 ± 2.1 mm (M) (P = 0.057); the mean height was 12.7 ± 2.7 mm (F) and 15.5 ± 4.1 mm (M); the mean lingual concavity angles were 64.2 ± 19.2° (F) and 66.3 ± 29.0° (M) (P = 0.006); the depth of the lingual concavity was 3.0 ± 2.0 mm (F) and 6.8 ± 15.8 mm (M) (P = 0.033). The C format was the most common (51.9%) followed by the U format (25%) and P (23.0%) (P = 0.001). In the thickness of slices 5, 10 and 15 mm, thickness B increased significantly for posterior and U formats (P=0.933). Conclusion: Lingual research was present in the sample in 25% of the attempts. The depth of the lingual concavity was greater in males. Posterior mandible thickness and height do not diverge according to gender(AU)

Efeitos de customizações da prótese total mandibular sobre a qualidade de vida, força de mordida e eletromiografia de músculos da mastigação de pacientes edêntulos: um estudo clínico analítico intervencional / Effects of mandibular complete denture customizations on quality of life, bite force, and masticatory muscle electromyography in edentulous patients: an interventional analytical clinical study

Objetivo: Avaliar se customizações da prótese total mandibular (reembasamento e restabelecimento da dimensão vertical de oclusão) influenciam na amplitude eletromiográfica dos músculos masseter e temporal, força máxima de mordida e qualidade de vida relacionada à saúde oral de indivíduos edêntulos. Materiais e métodos: Usuários de próteses totais que usavam o mesmo par de próteses por mais do que 5 anos foram incluídos (sem disfunção temporomandibular) (n=15). Avaliações de qualidade de vida (Oral Health Impact Profile for Edentulous ­ OHIP-EDENT), força máxima de mordida, e eletromiografia dos músculos masseter e temporal foram realizadas em 5 tempos diferentes (T1 ­ próteses antigas originais; T2 ­ após 18 dias de uso da prótese mandibular reembasada; T3 ­ após 18 dias do restabelecimento da dimensão vertical de oclusão; e T4 e T5 ­ 30 e 100 dias de uso de novas próteses totais. Resultados: Não houve diferenças significativas entre os pontos de tempo para todos os testes eletromiográficos e de força máxima de mordida. O OHIP-EDENT mostrou que o reembasamento pode contribuir para uma maior adaptação da prótese total mandibular e conforto do paciente (T2), em contrapartida T3 foi associado com o desconforto do paciente (p<0.05). Conclusão: Baseado na avaliação de qualidade de vida relacionada à saúde oral, o reembasamento da prótese total mandibular ocasionou um aumento do conforto mastigatório para os pacientes, e o restabelecimento prévio da dimensão vertical de oclusão causou um desconforto para os pacientes. A amplitude eletromiográfica mostrou que as customizações realizadas neste estudo não aumentaram ou diminuíram o esforço mastigatório significativamente. Além disso, todos os valores de força máxima de mordida observados estavam dentro do clinicamente aceitável(AU)

Objective: To evaluate whether customizations of mandibular complete dentures (relining and restoration of the vertical dimension of occlusion) influence the electromyographic amplitude of the masseter and temporal muscles, maximum bite force and oral health-related quality of life of edentulous individuals. Materials and methods: Complete denture wearers who wore the same pair of dentures for more than 5 years were included (without temporomandibular dysfunction) (n=15). Assessments of quality of life (Oral Health Impact Profile for Edentulous ­ OHIP-EDENT), maximum bite force, and electromyography of the masseter and temporal muscles were performed at 5 different times (T1 - original old dentures; T2 - after 18 days of wearing relined mandibular denture; T3 - after 18 days of restoration of the vertical dimension of occlusion; and T4 and T5 - 30 and 100 days of wearing new complete dentures. Results: There were no significant differences between the time points for all electromyographic and maximum bite force tests. The OHIP-EDENT showed that relining can contribute to greater adaptation of the mandibular denture and patient comfort (T2), in contrast, T3 was associated with patient discomfort (p<0.05). Conclusion: Based on the assessment of quality of life related to oral health, the reline of the mandibular complete denture caused an increase in masticatory comfort for the patients, and the previous definitive restoration of the vertical dimension of occlusion caused discomfort for patients. The electromyographic amplitude showed that the customizations performed in this study did not significantly increase or decrease masticatory effort. In addition, all observed maximum bite force values were within the clinically acceptable range(AU)

Prevalencia del segundo conducto radicular en incisivos inferiores y su importancia clínica / Prevalence of the second root canal in lower incisors and its clinical importance

La alta necesidad de tratamientos de endodoncia en los diferentes grupos dentales continúa siendo un desafío para los profesionales; ya que, es necesario el conocimiento tanto de las técnicas, materiales, equipo e instrumental, así como de las variantes del complejo sistema de conductos, de lo cual depende el éxito o fracaso. Las variaciones anatómicas incluyen la presencia de un segundo conducto radicular en incisivos inferiores (SCRII). La presente investigación es de tipo revisión bibliográfica, incluyéndose estudios del tipo: revisión de literatura y estudios descriptivos, en idioma inglés y español; se realizó la búsqueda entre los meses de enero y julio del 2021, en las bases de datos: Hinari, EBSCO host, Pubmed. Los resultados indican que la prevalencia de dos conductos en los incisivos inferiores varía desde 2% hasta un 77.9%; de manera individual en incisivos centrales inferiores la prevalencia es del 11.90% hasta 32.50% y en incisivos laterales inferiores se encuentran entre el 17.50% y el 58% de los casos. La ubicación de la entrada del SCRII ha sido objeto de múltiples estudios, encontrando que no existe consenso en este punto; pues se han descrito porcentajes similares entre los diferentes tercios (cervical, medio y apical), un factor influyente podría ser la etnia. La tomografía computarizada de haz cónico le ha ganado terreno a la radiografía convencional y uso de magnificación como técnica diagnóstica más efectiva; sin embargo, se sugiere realizar un estudio con pacientes salvadoreños para obtener un valor que oriente a los profesionales y así evitar fracasos de tratamientos endodónticos en dichos dientes.

The high need for root canal treatments in different dental groups continues to be a challenge for professionals; since, it is necessary the knowledge of the techniques, materials, equipment and instruments, as well as of the anatomical variants on which the success or failure depends. Anatomical variations include the presence of a second root canal in lower incisors (SCRII). The present investigation is of a literature review type, articles of the type were included: literature review and descriptive studies, papers in English and Spanish were included; the search was carried out between the months of January and July 2021, in the following databases: Hinari, EBSCO host, Pubmed. The results indicate that the incidence of finding two canals in both lower incisors range from 2% to 77.9%; individually in lower central incisors the prevalence is from 11.90% to 32.50% and in lower lateral incisors, it is found between 17.50% and 58% of cases. The location of the SCRII entrance has been the subject of multiple studies, finding that there is no consensus on this point; since similar percentages have been described among the different thirds (cervical, middle and apical), an influencing factor could be ethnicity. Cone beam computed tomography has gained ground over conventional radiography and the use of magnification as the most effective diagnostic technique; however, it is suggested to carry out a study with Salvadoran patients to obtain a value that guides professionals and thus avoid endodontic treatment failures in said teeth.

Valoración del grado de pigmentación en dientes acrílicos sometidos a humo del cigarrillo / Assessment of the degree of pigmentation in acrylic teeth subjected to cigarette smoke

INTRODUCCIÓN. Los cambios de color en los dientes acrílicos dependen de varios factores, con el humo de cigarrillo como uno de los principales agentes de igmentación de las prótesis. OBJETIVO. Valorar el grado de pigmentación en dientes acrílicos sometidos al humo del cigarrillo, mediante espectrofotometría digital. MATERIALES Y MÉTODOS. Estudio observacional, analítico, de caso y control. Muestra de 60 dientes acrílicos divididos en dos grupos: A (resina acrílica de 3 capas) y B (resina acrílica de 4 capas). Se subdividió en: grupo 1: dientes sometidos a humo de cigarrillo estándar con filtro de carbón; grupo 2: dientes sometidos a humo de cigarrillo estándar sin filtro; y, grupo 3: grupo control. Cada uno de éstos se expuso a 150 cigarrillos, 5 diarios durante 30 días y el grupo control fue mantenido a 37ºC en saliva artificial durante 30 días sin aplicación de humo de cigarrillo. Para la toma de color se empleó espectrofotómetro Vita Easyshade®. Los análisis se realizaron en el programa estadístico International Business Machines Statistical Package for the Social Sciences mediante la prueba de Kruskal-Wallis y comparaciones de Dunn. RESULTADOS. Se determinó que la pigmentación del grupo B fue mayor a la del grupo A, con una diferencia significativa entre ellos (p< 0,05). No se encontró datos estadísticamente significativos entre cigarrillos (con filtro - sin filtro). CONCLUSIÓN. La exposición al humo de cigarrillo pigmentó los dientes acrílicos de ambas propiedades siendo mayor en los dientes de resina acrílica de 4 capas.

INTRODUCTION. Color changes in acrylic teeth depend on several factors, with cigarette smoke as one of the main agents of denture pigmentation. OBJECTIVE. To assess the degree of pigmentation in acrylic teeth subjected to cigarette smoke, using digital spectrophotometry. MATERIALS AND METHODS. Observational, analytical, case-control study. Sample of 60 acrylic teeth divided into two groups: A (3-layer acrylic resin) and B (4-layer acrylic resin). It was subdivided into: group 1: teeth subjected to standard cigarette smoke with charcoal filter; group 2: teeth subjected to standard cigarette smoke without filter; and, group 3: control group. Each of these was exposed to 150 cigarettes, 5 daily for 30 days and the control group was maintained at 37ºC in artificial saliva for 30 days without application of cigarette smoke. Vita Easyshade® spectrophotometer was used for color determination. The analyses were performed in the statistical program International Business Machines Statistical Package for the Social Sciences using the Kruskal-Wallis test and Dunn's comparisons. RESULTS. It was determined that the pigmentation of group B was greater than that of group A, with a significant difference between them (p< 0,05). No statistically significant data was found between cigarettes (filtered - unfiltered). CONCLUSION. Cigarette smoke exposure pigmented acrylic teeth of both properties being higher in 4-layer acrylic resin teeth.

Bone evaluation of single edentulous areas of maxilla: short communication / Avaliação óssea de regiões maxilares candidatas à reabilitação unitária implantossuportada: uma comunicação curta

Objective: Evaluate the height and bone thickness in healed sites of single implant areas. Materials and Methods:In this cross-sectional study, cone-beam computed tomography (CBCT) images of single edentulous areas of maxilla of patients who needed aesthetic single implant rehabilitations were evaluated for measure the height and thickness using an implant planning software. Data were statistically analyzed using the Mann-Whitney and Pearson correlation test, considering the time, reason and region of tooth loss. For all tests, a p-value <0.05 was considered significant. Results: 48 patients with single tooth loss were included. The statistical analysis demonstrated that reason for the loss was not related to height or bone thickness. Bone thickness was statis-tical significant higher in the posterior region. For the anterior region, the bone thickness was significantly higher when the tooth was lost within 5 years. Pearson correlation test showed a moderate negative signifi-cant correlation between time of tooth loss and bone thickness in anterior region. Conclusion: Reason for tooth loss had no influence on the bone measurements of the residual ridge. In contrast, bone thickness may vary according to the region of tooth loss. The time of tooth loss and bone thickness in the anterior region were inversely proportional. Registration number at https://ensaiosclinicos.gov.br/rg/RBR-5cnyjj.

Objetivo: Avaliar a altura e espessura óssea em sítios unitários cicatrizados. Materiais e Métodos: Neste estudo transversal, imagens de tomografia computa-dorizada de feixe cônico (TCFC) de regiões edêntulas unitárias maxilares de pacientes candidatos a reabilitação unitária implantossuportada foram mensuradas em relação à altura e espessura óssea usando um software de planejamento de implante. Os dados foram analisados estatisticamente por meio do teste Mann-Whitney e de correlação de Pearson, considerando o tempo, o motivo e região da perda dentária. Para todos os testes, um valor de p <0,05 foi considerado significativo. Resultados: Foram incluídos 48 pacientes com perda dentária unitária. A análise estatística demonstrou que o motivo da perda dentária não influenciou na altura ou na espessura óssea. A espessura óssea foi estatisticamente maior na região posterior. Para a região anterior, a espessura óssea foi significativamente maior quando o dente foi perdido em até 5 anos. O teste de correlação de Pearson demonstrou uma correlação significativa negativa moderada entre o tempo de perda do dente e a espessura óssea na região anterior. Conclusão: O motivo da perda dentária não influenciou nas medidas ósseas do rebordo residual. Em contraste, a espessura do osso pode variar de acordo com a região da perda dentária. O tempo de perda dentária e a espessura óssea da região anterior foram inversamente proporcionais. Número de registro em https://ensaiosclinicos.gov.br/rg/RBR-5cnyjj

Seguimiento a 5 años de prótesis híbrida con subestructura sinterizada. Reporte de caso / Five-year follow-up of hybrid prosthesis with sintered substructure. Case report

RESUMEN: La rehabilitación de rebordes severamente atróficos mediante prótesis híbridas con subestructura cromo-cobalto fabricadas por sinterizado láser asegura el ajuste pasivo, aumentando la estabilidad de los tejidos de soporte a largo plazo. Los controles periódicos y enseñanza de técnicas de higiene son fundamentales para el éxito de rehabilitaciones complejas sobre implantes. El propósito de este reporte de caso es realizar la evaluación clínica y radiográfica a 5 años de prótesis híbridas maxilar y mandibular fabricadas mediante sinterizado láser, encontrándose resultados satisfactorios en la evaluación y seguimiento.

ABSTRACT: Rehabilitation of severely atrophic ridges using hybrid cobalt-chrome substructures manufactured by laser sintering ensures passive fit, increasing support tissue stability. Regular check-ups and the teaching of hygiene techniques are essential for the success of complex implant restorations. The purpose of this case report is to perform a 5-year clinical and radiographic evaluation of hybrid maxillary and mandibular prostheses manufactured using laser sintering, achieving satisfactory results in the evaluation and follow-up.

Overdentures as an alternative to conventional dentures: a micro-costing analysis for Public Health Service in Brazil / Overdentures como alternativa às próteses convencionais: uma análise de micro-custeio para o Sistema Único de Saúde

Abstract This study aimed to estimate cost and compatibility with public financial incentives of two technologies for treating the edentulous mandible: lower complete dentures (CD) and overdentures retained by two dental implants (OD). This study consisted of a partial economic evaluation, with a micro-costing bottom-up approach for the calculation of direct costs. The estimates involved the number of consultations, proportion of materials, equipment, instruments' lifetime, and human resources, described in the price panel website of the Ministry of Economy in Brazil. Complementary information was obtained from a panel of experts. A sensitivity analysis was based on 20% variation. The estimated cost of a CD was R$ 189.89 (base scenario), and this varied between R$ 151.91 and R$ 227.89 according to sensibility analysis. The cost of an OD was R$ 663.05 (ranging from R$ 795.66 to R$ 530.44 - 1US=R$ 3.80/July 2019). The Ministry of Health covers appropriately the costs of the CD and OD. Both technologies showed costs that are within the limits of financial public incentives obtained by municipalities. The technologies are economically viable and should be induced through public policies due to their positive impacts on several functional domains of health.

Resumo Estimar os custos e a compatibilidade dos incentivos públicos de duas tecnologias para o tratamento da mandíbula edêntula: prótese total convencional (PTC) e overdenture retida por dois implantes (OD). Este estudo consistiu em uma avaliação econômica parcial, com abordagem "bottom-up" para o cálculo dos custos diretos. As estimativas levaram em consideração o número de consultas, proporção de materiais, equipamentos, vida útil dos instrumentais e recursos humanos. Os custos foram baseados no painel de preços do Ministério da Economia do Brasil e informações complementares foram obtidas de um painel de especialistas. Uma análise de sensibilidade foi baseada na variação de 20% dos custos. Os custos da PTC foram estimados em R$ 189,89 (cenário base) com variação entre R$ 151,91 e R$ 227,89 na análise de sensibilidade. Os custos da OD foram R$ 663,05 (variando de R$ 795,66 a R$ 530,44). O Ministério da Saúde cobre apropriadamente os custos de ambas as tecnologias nos cenários base e mais otimista. Ambas as tecnologias apresentaram custos dentro dos limites dos incentivos públicos recebidos. As tecnologias são economicamente viáveis e devem ser induzidas por políticas públicas diante do impacto positivo em vários domínios funcionais da saúde.

Acesso extraoral para tratamento cirúrgico de fratura de mandíbula atrófica: relato de caso / Extraoral access for surgical treatment of atrophic jaw fracture: case report

Introdução: Por sua posição na face, a mandíbula é frequentemente atingida pelos traumas, surgindo em algumas estatísticas como o osso fraturado com maior incidência em face. Em fraturas de mandíbulas atróficas o tratamento conservador, com fixação intermaxilar não costuma ser uma opção viável pela falta de dentes e pequena área de contato ósseo existente. Dessa forma, a redução aberta e fixação interna estável tem sido o tratamento de escolha sempre que a condição do paciente permitir. Objetivo: relatar um caso de osteossíntese de fratura de mandíbula atrófica por acesso extraoral. Relato de caso: Paciente 64 anos, faioderma, sexo feminino, procurou o serviço de Cirurgia e Traumatologia Bucomaxilofacial da Universidade Federal da Bahia apresentando traumatismo facial por queda da própria altura, referindo severas queixas álgicas espontâneas em região mandibular. Ao exame físico notou-se edentulismo total em ambas as arcadas, edema, hematoma e degrau ósseo á palpação em região de corpo de mandíbula a direita, alémde mobilidade atípica a manipulação da mandíbula. Ao exame de imagem notou-se sinais de fratura em corpo mandibular direito e côndilo esquerdo. O tratamento instituído foiconservador para a fratura de côndilo e cirúrgico para a fratura de corpo, o acesso foi extraoral ea fixação rígida foi realizada com placa e parafusos dos dispositivos Load-Bearing. Considerações finais: A paciente não apresentou quaisquer déficits funcionais pós-procedimento cirúrgico, sendo o tratamento abertocom fixação interna estável bastante promissor por restabelecer a união de focos fraturados e deslocados, proporcionando estabilidade da fratura e conforto imediato para a paciente(AU)

Introduction: Due to its position on the face, the jaw is frequently affected by trauma, appearing in some statistics as the fractured bone with a higher incidence in the face. In fractures of atrophic jaws, conservative treatment, with intermaxillary fixation, is not usually a viable option due to the lack of teeth and small area of existing bone contact. Thus, open reduction and stable internal fixation have been the treatment of choice whenever the patient's condition permits. Objective: to report a case of osteosynthesis of atrophic mandible fracture through extraoral access. Case report: Patient 64-year-old, female, sought the service of Maxillofacial Surgery and Traumatology at the Federal University of Bahia presenting facial trauma due to falling from his own height, referring to severe spontaneous pain complaints in the mandibular region. On physical examination, total edentulism was noted in both arches, edema, hematoma and bone step on palpation in the right jaw body region, in addition to atypical mobility in the jaw manipulation. On imaging examination, signs of fracture were noted in the right mandibular body and left condyle. The treatment instituted was conservative for condyle fracture and surgical for body fracture, access was extraoral and rigid fixation was performed with plate and screws of the Load-Bearing devices. Final considerations: The patient did not presente any functional deficits after the surgical procedure, and the open treatment with stable internal fixation is very promising for restoring the union of fractured and displaced foci, providing fracture stability and immediate comfort for the patient(AU)

Factors associated with edentulism in individuals with chronic kidney disease undergoing hemodialysis: a cross-sectional study / Fatores associados ao edentulismo em indivíduos com doença renal crônica em hemodiálise: um estudo transversa

Introduction: Chronic kidney disease (CKD) is a progres-sive condition characterized by structural or functional abnormalities of the kidney. CKD may be associated with several oral alterations, such as higher prevalence rate of dental caries, periodontal disease, xerostomia, candidiasis and burning mouth. The aim of the study was to identify risk factors associated with edentulism in adults with CKD undergoing hemodialysis. Methods: A cross-sec-tional study was conducted with 650 individuals aged 18 to 90 years undergoing hemodialysis in southeastern Brazil. Oral clinical examination and administration of a questionnaire addressing demographic characteristics and dental history were performed. The study received approval from the Human Research Ethics Committee of UFMG. Findings: A total of 183 participants were eden-tulous (28.2%). Individuals with less schooling (OR = 3.99; 95% CI: 2.34-6.79), those who had not been to a dentist in the previous six months (OR = 2.49; 95% CI: 1.52-4.08), those who rated their own smile as excellent or good (OR = 2.00; 95% CI: 1.35-2.97) and those with some mucosal alteration (OR = 4.17; 95% CI: 2.83-6.13) had a greater chance of belonging to the edentulous group. Discussion: The present findings can contribute to the establishment of public health policies aimed at guiding dental care programs for individuals with chronic kidney disease that take into account the specific needs of this population. Conclusion: Edentulism was associated with low schooling, a lack of dental care in the previous six months, a positive self-perception of one's smile and alterations in the oral mucosa.

Introdução: A doença renal crônica (DRC) é uma condição caracterizada por anormalidades estruturais ou funcionais do rim. A DRC pode estar associada a diversas alterações bucais, como maior prevalência de cárie dentária, doença periodontal, xerostomia, candidíase e queimação bucal. O objetivo deste estudo foi identificar os fatores de risco associados ao edentulismo em indivíduos com DRC em tratamento com hemodiálise. Materiais e Métodos: Foi realizado um estudo transversal com 650 indivíduos de 18 a 90 anos em hemodiálise no sudeste do Brasil. Foi realizado exame clínico oral e aplicação de questionário abordando características demográficas e histórico odontológico. O estudo foi aprovado pelo Comitê de Ética em Pesquisa em Seres Humanos da UFMG. Resultados: Um total de 183 participantes eram edêntulos (28,2%). Indivíduos com menor escolaridade (OR = 3,99; IC 95%: 2,34-6,79), aqueles que não foram ao dentista nos últimos seis meses (OR = 2,49; IC 95%: 1,52-4,08), aqueles que avaliaram o seu próprio sorriso como excelente ou bom (OR = 2,00; IC 95%: 1,35-2,97) e aqueles com alguma alteração de mucosa (OR = 4,17; IC 95%: 2,83-6,13) tiveram maior chance de pertencer ao grupo de edêntulos. Discussão: Os presentes achados podem contribuir para o estabelecimento de políticas públicas de saúde voltadas a nortear programas de atenção odontológica à pessoa com doença renal crônica que atendam às necessidades específicas dessa população. Conclusão: O edentulismo esteve associado à baixa escolaridade, falta de atendimento odontológico nos últimos seis meses, sorriso autoavaliado positivo e alterações mucosas.

Tilted implantation technique for edentulous patients / 华西口腔医学杂志

The tilted implantation technique is characterized by placing the implant at an angle of more than 15° and less than 45° from the horizontal plane. This technique can avoid damaging the maxillary sinus, inferior alveolar nerve, nasal base, and other anatomical structures when the height of the upper and lower jaw available bone is insufficient, to maximize the use of available bone and avoid a large range of bone increment. The tilted implantation technique can reduce the trauma of the surgery, increase the possibility of immediate restoration and shorten the treatment cycle, which has been widely used clinically. In this review, the scope of application, design elements, design scheme and complications of the tilted implantation technique for edentulous patients will be described.

Interarch distance is a target restorative space value: clinical decisionmaking of implant restoration guided by measured value / 华西口腔医学杂志

When design an implant restoration for edentulous patients, many doctors ignore the sufficiency of the interarch distance (vertical distance) or horizontal distance of the patient to accommodate the superstructure and restoration before designing the implant plan. However, the connotation of measuring the interarch distance or horizontal distance has not been clarified in clinical practice. It is often based on visual estimation after operation, and the decision-making path of implant restoration is inverted, resulting in many mistakes regarding the restoration after implantation. The main reason is the lack of standardized paths and practical methods to use before surgery. This article recommended initially establishing a maxillo-mandibular relationship based on natural teeth, old dentures, or new ones and then using the height and horizontal distance or angle of the target restorative space, which was easier to grasp as the measured index. The minimum vertical distance (including the height of the gingival surface and the bone surface) and the horizontal distance (or the angle from the bone or gingival surface to the proposed occlusal plane) should be measured before operation. A decision tree of edentulous jaw restoration guided by the values of the repair space was established based on the measured values. This article clarified the measuring points and planes and thus provided a quantitative relationship basis for the design of implant restoration.

Clinical assessment of pterygoid and anterior implants in the atrophic edentulous maxilla: a retrospective study / 华西口腔医学杂志

OBJECTIVES@#This study aims to evaluate the short-term clinical outcomes and patient satisfaction of anterior and pterygoid implants in the rehabilitation of edentulous maxilla with posterior atrophy.@*METHODS@#Given a minimum follow-up of 1 year, 25 patients with fixed maxillary rehabilitation over anterior and pterygoid implants were enrolled in this retrospective study. The implant survival rates, peri-implant soft tissue status (including probing depth, modified sulcus bleeding index, and plaque index), marginal bone loss, and patient satisfaction were measured.@*RESULTS@#The survival rates for anterior and pterygoid implants at 1-year follow-up were 96.5% and 97.8%, respectively (@*CONCLUSIONS@#For the edentulous maxilla with posterior atrophy, full-arch fixed prostheses supported by anterior and pterygoid implants has an acceptable short-term clinical outcome and excellent patient satisfaction. It may be considered as a predictable and feasible method for maxillary rehabilitation.

Previsibilidade de reabilitações de maxilas edêntulas com a técnica all-on-four: revisão de literatura / Previsibility of edental jaw rehabilitations with the all-on-four technique: literature review

Objetivo: avaliar a previsibilidade das reabilitações de maxilas edêntulas através da técnica all-on-four, mensurada pelas tensões sobre implantes em estudos laboratoriais e sobrevida de próteses, perda óssea marginal e sucesso dos implantes em estudos clínicos. Revisão de literatura: foi executada uma busca na literatura nas bases de dados Lilacs, SciELO e PubMed/Medline, utilizando termos relacionados ao tema, sem restrição temporal e adaptados para cada base. As buscas foram realizadas por um único examinador no período de setembro a novembro de 2019. Após a leitura crítica dos 21 artigos selecionados, constata-se que existem vários estudos com muitos delineamentos que avaliaram a previsibilidade mensurada de várias formas. Considerações finais: diante das evidências científicas encontradas, a reabilitação de maxilas edêntulas com a técnica all-on-four demonstra ser previsível e estável. Estudos retrospectivos, prospectivos e revisões sistemáticas relatam altos índices de sucesso, baixa perda óssea marginal, embasando o uso da técnica all-on-four na odontologia.(AU)

Objective: to assess the predictability of edentulous maxillary rehabilitation using the all-on-four technique, measured by tensions over implants in laboratory studies and prosthetic survival, marginal bone loss and implant success in clinical studies. Literature Review: A literature search was performed in the Lilacs, SciELO and PubMed/ Medline databases, using terms related to the theme, without time restriction and adapted for each base. The searches were carried out by a single examiner from September to November 2019. After a critical reading of the 21 selected articles, it appears that there are several studies with many designs that evaluated the predictability measured in various ways. Final considerations: In view of the scientific evidence found, the rehabilitation of edentulous jaws with the all-on-four technique proves to be predictable and stable. Retrospective, prospective studies and systematic reviews report high success rates, low marginal bone loss, basing the use of the all-on-four technique in dentistry.(AU)

Visual sensitivity threshold of lateral view of nasolabial Angle changes in edentulous jaw patients / 北京大学学报(医学版)

OBJECTIVE@#To study the visual sensitivity threshold of physician's naked eye to the difference of nasolabial angle in edentulous jaw patients, and to provide a reference value for the study of aesthetic evaluation of soft tissue profile for the difference of nasolabial angle that can be recognized by human eyes.@*METHODS@#Three-dimensional facial images of three edentulous patients with different diagnostic dentures introoral were obtained. Lateral screenshots of each patient's three-dimensional facial image with the same scale were obtained by using reverse engineering software (Geomagic studio 2014).The screenshot of the patient's three-dimensional facial image with suitable lip support (The suitable lip support was confirmed by both patients and prosthodontists who had clinical experience for more than 20 years) was taken as the reference picture, and the remaining pictures were grouped with it respectively. All the pictures were observed in random order by the subjects. Fifteen dentists were asked to judge the difference of nasolabial angle between the two pictures of each group on the computer screen. The difference of nasolabial angle between the two pictures in each group was measured and calculated. The ROC curve was drawn, and the best cut-off value was calculated as the visual sensitivity threshold.@*RESULTS@#The data of the 15 subjects were used to draw ROC curves separately. The maximum and minimum best cut-off values were 5.55 degrees and 3.12 degrees respectively. The ROC curve of the whole 15 subjects was drawn after data aggregation, and the best cut-off value was 5.36 degrees (AUC=0.84>0.5, P=0.000<0.05). When the difference of nasolabial angle was above 5.36 degrees, the subjects could recognize it effectively.@*CONCLUSION@#There is a visual limit in the observation of the nasolabial angle with the naked eye. In this study, a visual sensitivity threshold of 5.36 degrees for the difference of the nasolabial angle was obtained. The difference of nasolabial angle below this value can be regarded as no clinical significance. This result provides a reference value for human eyes to recognize the difference of nasolabial angle in soft tissue profile aesthetic evaluation. It can be applied to the aesthetic evaluation of soft tissue profile and can be used as the error level of related research with nasolabial angle as an index for accuracy evaluation.