Masticatory performance, self-perception of oral health, oral health-related quality of life and nutritional status of completely edentulous elderly patients submitted to different rehabilitation treatments: A cross-sectional study.

BACKGROUND: The impact of treatments on completely edentulous individuals on masticatory performance (MP), oral health-related quality of life (OHRQoL), nutritional status (NS) and socio-economic profile (SP) is unclear in the literature. OBJECTIVE: To compare the MP, OHRQoL, NS and SP of totally edentulous elderly users of bimaxillary complete dentures (CD) and users of lower implant-supported fixed complete dentures (IFCD). METHODS: Forty participants were allocated into groups according to rehabilitation treatment (n = 20): bimaxillary CD (G1) and lower IFCD, and upper CD (G2). The evaluation of MP used almonds by the method of sieves. Four questionnaires (Geriatric Oral Health Assessment Index-GOHAI and Oral Health Impact Profile Edent-OHIP-Edent, Brazilian Economic Classification Criteria-ABEP and Mini Nutritional Assessment-MNA) were applied to assess the OHRQoL, SP and NS of the elderly, respectively. After evaluating the statistical assumptions, the Mann-Whitney (α = .05) test was applied to compare the groups regarding MP, OHRQoL, NS and SP. Spearman's correlation (α = .05) was performed to verify the correlation between the MP, the OHRQoL and the NS of the participants. RESULTS: G2 showed better MP (p < .05) in all masticatory cycles, OHRQoL (p < .05) and NS than the G1. However, the participants' self-perception of oral health did not differ between groups (p < .05). A moderate negative correlation was found between MP and OHRQoL for 40 masticatory cycles (r2 = -0.513; p = .001). CONCLUSION: Individuals rehabilitated with IFCD had a higher average monthly family income and achieved superior behaviour in MP and OHRQoL, in addition to lower risks of malnutrition when compared to individuals using bimaxillary CD.

Handgrip force and bite force in dentulous and edentulous individuals.

BACKGROUND: The literature is unclear about bite force (BF) and handgrip force (HF) in a specific group of different ages and dentate conditions, or even a predictive model for each specific group, using BF and HF as factors. OBJECTIVE: To establish the correlation between HF and BF in female participants with distinct ages and dentate conditions; also create a predictive model of BF as a function of HF. METHODS: Participants were divided into three groups (GI: young natural dentate women, n = 65; GII: adult natural dentate women, n = 67; and GIII: edentulous women users of bimaxillary complete dentures, n = 67) and subjected to an HF measurement test using a digital dynamometer. Subsequently, BF was measured using a digital gnathodynamometer in the molar region. Pearson correlation coefficient (r) and multivariate analysis of variance (α = 0.05) were performed, and simple linear regression was used to obtain a model to predict BF from HF for each group separately (α = 0.05). RESULTS: All groups presented moderate and strong correlations among the variables (GI: r = 0.838; GII: r = 0.714; GIII: r = 0.646). A significant difference in BF was observed (GI > GII > GIII; p < .05). GIII presented a significantly lower HF than the other groups (p < .05). Besides, three equations predicting BF, using HF, were obtained for use in young/adult dentate and edentulous women. CONCLUSION: All groups found a positive and significant correlation between BF, HF and groups. HF can be a simple and efficient method for predicting BF using the predictive models developed for women with good health.

Accuracy of Impression Techniques with Maxillary Angled Implants Using Trays and Multifunctional Guides.

PURPOSE: The purpose of this study was to evaluate in vitro the accuracy of different splinting techniques using transfers combined with different tray types. MATERIALS AND METHODS: The research group fabricated a maxillary master cast with four implants and a passive metallic bar on this master cast. For the impression techniques, 48 casts were used with six different impression techniques: (1) metal tray with resin splinted transfers, (2) metal tray with metal and resin splinted transfers, (3) plastic tray with resin splinted transfers, (4) plastic tray with metal and resin splinted transfers, (5) multifunctional guide with resin splinted transfers, and (6) multifunctional guide with metal and resin splinted transfers (n = 8) using polyvinyl siloxane impression material. This study used a passive metallic bar to measure the malalignment between the framework and the analogs (A, B, C, and D) in 2D and 3D. The master and experimental casts were scanned with a contact scanner to compare the accuracy in 3D impression techniques. Discrepancies between the analogs were measured in three x-, y-, and z-axes. RESULTS: There was no statistically significant difference (P > .05) between the groups in vertical malalignments (2D). In the 3D evaluation, for the z-axis and combination of xz-axis, plastic tray with metal, and resin splinted transfers (z = 487 µm; xz = 888 µm), there was a statistically significant difference compared with the multifunctional guide and resin splinted transfers (z = 772 µm; xz = 1,380 µm). When analyzing by analog, in C, the multifunctional guide with metal and resin splinted transfers (302 µm) presented a statistically significant difference compared with the multifunctional guide and resin splinted transfers (492 µm). CONCLUSION: The evaluation methods for the accuracy impression technique presented different results between them. There was no difference in vertical malalignments (2D), but in 3D, the bonding with metal and acrylic resin presented better results than the bond with only acrylic resin when using the plastic tray and multifunctional guide, respectively, in the z-axis and the combination between the xz-axes. The bonding technique of the transfers with metal and acrylic resin presents better results in the 3D analysis for the multifunctional guide impressions.

Evaluación de la precisión de impresiones sobre implantes usando guía multifuncional en el sistema all-on-four / Accuracy of implant impression using a multifunctional guide in the All-on-Four treatment concept

ABSTRACT Introduction: The passivity of prosthetic components is one of the most important prerequisites in oral implant rehabilitation for maintenance of osseointegration. Objective: Thus, the present study analyzed in vitro the accuracy of different molding techniques in prosthetic rehabilitation on angled implants installed in an anatomical model of a metallic edentulous maxilla. Methods: Laboratory experiment study. A reference metal model of an edentulous maxilla was used. A metal framework was used for the misadaptation assessment. Three groups (n= 10) were compared and impressions were made with vinyl-polysiloxane and casts were obtained with type IV stone: (1) Impression with a metallic open-tray without splinted transfers; (2) Impression with a metallic open-tray and metal splinted transfers; (3) Impression with a multifunctional guide and metal splinted transfers. Misadaptation was assessed with the aid of a stereomicroscope and measuring software. Data were submitted to ANOVA with Welch correction and the Games-Howell post-hoc test with the significance set at 5 percent. Results: Misadaptation (µm) was 110,23 ± 30,94, 37,53 ± 3,92, and 37,69 ± 2,79 for the the groups. Statistically significant differences between impression with a metallic open-tray with and without splinted transfers were observed (p < 0,001). No significant differences between the other types of impression. Conclusions: Impression with a metallic open-tray without splinted transfers and with a multifunctional guide splinted with metal transfers were the most precise methods resulting in higher accuracy in transferred implants(AU)

RESUMEN Introducción: La pasividad de los componentes protésicos es uno de los prerrequisitos más importantes para el mantenimiento de la osteointegración en la rehabilitación oral sobre implantes. Objetivo: Evaluar in vitro la precisión de diferentes técnicas de impresión en rehabilitación sobre implantes inclinados instalados en un modelo anatómico de un maxilar metálico desdentado. Métodos: Estudio de laboratorio de tipo experimental. Se utilizó un modelo metálico de referencia de un maxilar desdentado. Fue utilizada una barra metálica para la evaluación de la desadaptación. Se compararon tres grupos (n = 10), se realizaron impresiones con polivinilsiloxano y se obtuvieron modelos con yeso piedra tipo IV: (1) impresión con una cubeta metálica abierta sin unión de los transferentes; (2) impresión con una cubeta metálica abierta y unión de los transferentes con cilindros metálicos; (3) impresión con una guía multifuncional y unión de los transferentes con cilindros metálicos. La desadaptación se evaluó con la ayuda de un microscopio estereoscópico y un software de medición. Los datos se enviaron a ANOVA con la corrección de Welch y la prueba post-hoc de Games-Howell con la significación establecida en 5 por ciento. Resultados: La desadaptación (µm) fue de 110,23 ± 30,94; 37,53 ± 3,92 y 37,69 ± 2,79 para los grupos, respectivamente. Se observaron diferencias estadísticamente significativas entre la impresión con cubeta abierta metálica con y sin unión de los transferentes (p <0,001). No hubo diferencias significativas entre los otros tipos de impresiones. Conclusiones: La impresión con cubeta abierta metálica sin unión de los transferentes y con una guía multifuncional con unión de los transferentes con cilindros metálicos fueron los métodos más precisos que dieron como resultado una mayor precisión en la transferencia de la posición de los implantes(AU)

Impact of Physical Chemical Characteristics of Abutment Implant Surfaces on Bacteria Adhesion.

Surface attachment is the first step in biofilm formation, and the ability of bacteria to adhere to surfaces and develop a biofilm is directly influenced by electrostatic interactions between the bacteria and the chemical composition of material surfaces. Here, we investigated the influence of physical and chemical characteristics of titanium (Ti) and zirconia (ZrO2) as implant abutment surfaces on the bacterial adhesion phase and compared the results to bovine enamel (BE) simulating a human tooth. To achieve this goal, we used 2 common pathogens of the oral cavity, Streptococcus mutans UA140 and Porphyromonas gingivalis 33277. To investigate the influence of material surfaces on bacterial adhesion, we studied the surface free energy as well as the topography by atomic force microscopy, and the chemical elements composition by scanning electron microscopy equipped with an energy dispersive X-ray spectroscope. Our results indicated a hydrophobic characteristic for all of the materials; however, the presence of polar and nonpolar components could aid in understanding why greater numbers of bacteria had adhered to BE compared to the other surfaces. Our confocal microscopy data support the proposition that electrostatic interactions, indeed, affected the initial adhesion phase. Within the limitations of a laboratory study, the results revealed bacterial adhered on BE and no bacteria could be observed by confocal images on Ti and ZrO2 implant abutment surfaces.