Failure and survival rates of implant-supported CAD-CAM multilayer ceramic restorations fused with nano-fluoropatite: a retrospective study

Objective: The aim of this study was to clinically evaluate the failure and survival rates of implant supported screw-retained multilayer ceramics, made with CAD-CAM technology, with zirconia infrastructure and lithium disilicate superstructure, using nano-fluoropatite as a fusion ceramic. Materials and Methods: This study was carried out on a private clinic in Marília – SP, Brazil. All the eligible patients have had received implant supported screw-retained multilayer ceramics, with CAD-CAM zirconia infrastructure and lithium disilicate superstructure, fused with nano-fluoropatite. To determine the failure and survival rates, clinical evaluations were performed, classifying the ceramic restorations as: "Type 1a: Non-critical flaw inside the veneering ceramic", “Type 1b: Critical fissure in the veneering ceramic”, "Type 2a: Non-critical chipping”, “Type 2b: Critical chipping", "Type 3: Chipping of the veneering ceramic with Zirconia core exposure" or "Type 4: Fracture of the Zirconia core" according to the presence of chippings or delaminations. In addition, peri-implant evaluations were performed using Scores 0, 1, 2 or 3 to classify the Index of Gingival Bleeding (mBI) and Index of plaque accumulation (mPI). The Kaplan-Meier test was used to estimate the survival rate from the ceramic and restoration systems. Results: A total of 17 prostheses (6 multiple splinted and 11 single ones) were evaluated, from 6 to 66 months of follow-up. All patients (100%) were satisfied or very satisfied with the prostheses (mean of 9.4 on the graduated scale). All the prostheses (100%) presented no failures, both in infrastructures and superstructures. The following figures were observed for the mBI: 7 prostheses presented Score 0 (41.17%); 3 Score 1 (17.64%); 6 Score 2 (35.29%); and only 1 Score 3 (5.88%). For mPI, 6 prostheses Score 0 (35.29%) were observed; 9 prostheses Score 1 (52.94%); no prosthesis Score 2 (0%); and 2 prostheses Score 3 (11.76%). Only 1 of the prostheses presented significant complications, resulting from a periimplantitis. The Kaplan-Meier survival rate was 100% for the ceramic system and 85% for the restorarion system. Conclusion: This cross-sectional study presented absence of failures and, consequently, high survival rate in the new nano-fluoropatite fusion method in zirconia- based multilayer CAD-CAM restoration, and CAD_CAM lithium disilicate superstructure.FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisDissertação (Mestrado)Objetivo: O objetivo deste trabalho foi avaliar clinicamente a taxa de falha e de sobrevida de cerâmicas multilayers sobre implante, confeccionadas com tecnologia CAD-CAM, possuindo infraestrutura em Zircônia, recobrimento em Dissilicato de Lítio, utilizando-se Nano-fluoropatita como cerâmica de fusão. Materiais e Métodos: Este estudo foi realizado em uma clínica particular em Marília – SP, Brasil. Todos os pacientes considerados elegíveis para receberam próteses multilayers cerâmicas implanto-suportadas parafusadas, com infraestrutura em Zircônia e cerâmica de recobrimento em Dissilicato de Lítio, ambas confeccionadas com CAD-CAM e fusionadas com Nano-fluoropatita. Para determinar as taxas de falha e sobrevida, avaliações clínicas foram realizadas, classificando as restaurações cerâmicas em falhas “Tipo 1a: Falha não crítica à sobre-estrutura”, “Tipo 1b: Fissura crítica à sobre-estrutura”, “Tipo 2a: Delaminação não crítica”, Tipo 2b: Delaminação crítica”, “Tipo 3: “Chipping” na sobre-estrutura com exposição da infraestrutura de Zircônia” ou “Tipo 4: Fratura da infraestrutura de Zircônia”. Além disto, realizou-se avaliações peri-implantares a partir de Escores 0, 1, 2 ou 3 para classificação do Índice de Sangramento do Sulco Gengival (ISSG) e Índice de Acúmulo de Placa Dental (ISPD). O teste e Kaplan-Meier foi utilizado para estimar as taxas de sobrevida do sistema cerâmico e do sistema restaurador, a partir dos dados coletados nas avaliações clínicas. Resultados: Um total de 17 próteses (6 múltiplas ferulizadas e 11 unitárias) foram avaliadas, de 6 a 66 meses de acompanhamento. Todos os pacientes (100%) se mostraram satisfeitos ou muito satisfeitos com as próteses (média de 9,4 na escala graduada). Todas as próteses (100%) apresentaram ausência de falhas, tanto nas infraestruturas, quanto nas sobre-estruturas. Portanto, nenhuma das restaurações (0%) apresentou falhas do Tipo 1, do Tipo 2, do Tipo 3 ou do Tipo 4. Para a avaliação peri-implantar observou-se os seguintes valores para os ISSG: 7 próteses apresentaram Escore 0 (41,17%); 3 Escore 1 (17,64%); 6 Escore 2 (35,29%); e apenas 1 Escore 3 (5,88%). Para os IAPD, foram observados: 6 próteses Escore 0 (35,29%); 9 próteses Escore 1 (52,94%); nenhuma prótese Escore 2 (0%); e 2 próteses Escore 3 (11,76%). Apenas 1 das próteses apresentou complicações importantes, resultantes de uma peri-implantite, o que lhe foi atribuído Escore 3 para ambas as classificações. A taxa de sobrevida de Kaplan-Meier foi de 100% para o sistema cerâmico e 85% para o sistema restaurador. Conclusão: O presente estudo apresentou a ausência de falhas e, consequente, alta taxa de sobrevida do novo método de fusionamento entre camadas de restaurações multilayers CAD-CAM, com infraestrutura em Zircônia e sobre-estrutura em Dissilicato de Lítio, utilizando a Nano-fluoropatita como cerâmica de fusão

COMPORTAMENTO DA MADEIRA DE Tectona grandis FRENTE AO INTEMPERISMO

A qualidade da madeira pode ser alterada por intempéries que podem diminuir sua vida útil, bem como alterar a sua cor, que é um fator preponderante no mercado madeireiro, muitas vezes determinando seu preço final, principalmente quando utilizada em ambientes internos. A Teca (Tectona grandis Linn. F.) é uma madeira comercialmente valiosa, possui propriedades físico-mecânicas e características qualitativas como a cor, o desenho e a densidade desejáveis em produtos que requerem um bom acabamento. O objetivo deste estudo foi avaliar o processo de intemperismo artificial da madeira de Teca submetida a 5 ciclos de irradiação UVA de 1,55 W/m² a 340 nm de comprimento de onda, conforme a norma ASTM G154. O sistema CIE L*a*b* de 1976 mostrou as modificações das cores. A mudança da cor natural da madeira, indicativo do processo de fotodegradação, foi monitorada por espectrocolorimetria. Amostras da espécie não sofreram alteração de cor frente ao intemperismo, permanecendo na cor marrom oliva, tornando-a uma opção frente a outras espécies madeireiras de uso em escala industrial, principalmente naqueles onde consegue-se agregar mais valor

Colorimetria e espectroscopia no infravermelho médio em madeira de curupixá frente ao intemperismo artificial com produtos de acabamento

This study investigates the changes in color and in the chemical structures of the surface of curupixá wood (Micropholis sp.), which was exposed to artificial weathering with two wood finishing products. We treated the sample surfaces with varnish and stain, and then we set them to artificial weathering for 700 hours, in accordance with ASTM G154 (2006). Our team used The Fourier Transform Mean Infrared (FT-MIR) and the CIELAB (1976) system in order to outline changes in the chemical and colorimetric structure of the wood surface, respectively. The color of curupixá wood got darker after applying finishing products. The color variation following the weathering process was appreciable in the control sample and very appreciable in the treated wood sample. The analysis of medium infrared spectroscopy demonstrated the depolymerization of lignin accompanied by the formation of carbonyls in all cases. In addition, mid-infrared displayed a concentration drop due to the heavy metal leaching. These ocurrences reveal degradation in the structural chemical components of the wood, and that the finishing products did not affect the weathering process at all.O objetivo do estudo foi investigar alterações de cor e de estruturas químicas da superfície da madeira de curupixá (Micropholis sp.), submetida ao intemperismo artificial, com dois produtos de acabamento. As superfícies das amostras foram tratadas com verniz e stain, e submetidas ao intemperismo artificial por 700 horas de acordo com a norma ASTM G154 (2006). O infravermelho médio com transformada de Fourier (FT-MIR) e o sistema CIELAB (1976) foram utilizados para caracterizar mudanças na estrutura química e colorimétricas da superfície da madeira, respectivamente. Em relação à cor, a madeira de curupixá escureceu com a aplicação dos produtos de acabamento. O intemperismo alterou de forma apreciável a cor da testemunha, e de forma muito apreciável a madeira tratada com os dois produtos de acabamento. A análise de espectroscopia no infravermelho médio mostrou que, em todos os casos, sucedeu a despolimerização da lignina acompanhada da formação de carbonilas, além de queda em suas concentrações devido à lixiviação dos metais pesados. Tudo isso indica que houve degradação dos componentes químicos estruturais da madeira e que não houve influência dos produtos de acabamento no processo de intemperismo

Effect of simulated brushing and disinfection on the surface roughness and color stability of CAD-CAM denture base materials.

PURPOSE To evaluate the effect of simulated brushing and chemical disinfection on the surface roughness and color stability of CAD-CAM denture base materials and to compare with those of a heat-cured denture base material. MATERIAL AND METHODS Disk-shaped specimens (Ø 10mm × 2 mm) were prepared from 3 CAD-CAM denture base resins (AvaDent, Ava; Merz M-PM, Merz; Polident d.o.o, Poli) and a heat-cured polymethylmethacrylate resin (Promolux, Conv) (n = 30). After polishing, baseline surface roughness (Ra) and color coordinates were measured. The measurements were repeated after 20000 cycles of simulated brushing, and the specimens were divided into 3 groups according to disinfection protocol (distilled water, 1% sodium hypochlorite (NaOCl), and effervescent tablet) (n = 10). After 9 cleaning cycles over a period of 20 days, Ra and color coordinates were remeasured. Color differences (ΔE00) were calculated by using CIEDE2000 formula. One-way analysis of variance (ANOVA) and pairwise t-tests were used to analyze Ra and ΔE00 data, while repeated measures ANOVA test was used to compare baseline, after brush, and after disinfection Ra values (α = 0.05). RESULTS Brushing did not affect the Ra values of tested materials (P ≥ .08). Both before and after brushing, Merz and Conv had higher Ra values than Poli and Ava (P < .001). Among disinfectants, effervescent tablet led to the lowest Ra for Merz (P = .003) and the highest Ra for Poli (P ≤ .039). Only NaOCl resulted in significant differences among the Ra of materials (P < .001), as Merz and Conv had higher Ra values than Poli (P ≤ .002). Repeated measures ANOVA revealed that effervescent tablet disinfection of Merz led to lower Ra values than those of baseline and after brushing (P ≤ .042). After brushing, Ava and Conv had higher ΔE00 values compared with Merz and Poli (P ≤ .015). When compared with other disinfection protocols, effervescent tablet led to higher ΔE00 values for Merz and Poli (P < .001). Significant differences were observed among materials when NaOCl was used; Conv had higher ΔE00 values than Ava and Merz (P = .004). CONCLUSIONS Brushing did not increase the surface roughness of materials. Disinfection protocol's effect on the surface roughness varied. The effect of brushing on the color of materials varied; color of Ava and Conv was affected from brushing more than the other materials. Color stability of materials varied depending on the disinfection protocol. Effervescent tablet caused higher color change with Merz and Poli compared with other disinfectants. NaOCl led to small color change for Poli, Ava, and Merz materials

Stainability and translucency of potassium aluminum sulfate applied computer-aided design and computer-aided manufacturing materials after coffee thermocycling.

OBJECTIVE The purpose of this in vitro study was to evaluate the effect of potassium aluminum sulfate (alum) application on the stainability and translucency of computer-aided design and computer-aided manufacturing (CAD-CAM) materials after coffee thermocycling (CTC). MATERIALS AND METHODS Disk-shaped specimens (Ø10 × 1 mm; N = 200) were fabricated by using additively (Crowntec [CT] and Varseo Smile Crown Plus [VS]) and subtractively manufactured (Brilliant Crios [RCR], CEREC Block [FC], and Vita Enamic [VE]) CAD-CAM materials and polished. All specimens were randomly divided into two groups as alum applied and control (n = 10). All specimens were then subjected to CTC (10,000 cycles at 5-55°C) and color coordinates were measured at each time interval. Color differences (ΔE00 ) and relative translucency parameters (RTPs) were calculated and the data were statistically analyzed (a = 0.05). RESULTS Among tested time intervals, alum applied specimens had their lowest ΔE00 after alum application (p ≤ 0.006), except for FC (p = 0.177). In addition, alum applied RCR had lower ΔE00 values than its control specimens (p = 0.029). Alum applied specimens had their lowest RTP after CTC (p < 0.001) and alum application decreased the RTP of CT (p = 0.010). CTC reduced the RTP of all materials in control groups (p < 0.001). Alum applied CT had higher RTP than its control specimens (p = 0.049). CONCLUSIONS Alum application's effect on color change varied depending on the material and alum mostly resulted in clinically acceptable changes in translucency. CTC led to unacceptable color and translucency changes based on previously reported threshold values. CLINICAL SIGNIFICANCE Optical properties of CAD-CAM materials and the sustainability of these properties over time is critical for longevity. Alum may improve the color stability of reinforced composite resin when subjected to long-term coffee consumption

Assessment and Improvement of Masticatory Performance in Frail Older People: A Narrative Review

According to the World Health Organization (WHO), the estimated number of older adults is around 962 million and is projected to increase to 2.1 billion by 2050. The oral frailty concept is associated with gradual oral function loss in relation to aging. There is a need to emphasize the improvement of oral function based on an evaluation of masticatory performance in patients with various oral conditions or systemic diseases and especially in the frail elderly. The present narrative review presents an overview of the current state of the assessment and improvement of masticatory performance in frail older people. To fully encompass oral frailty, oro-facial hypofunction, or oro-facial fitness, dental Patient Reported Outcomes (dPROs) should be included; nevertheless, there are limited evidence-based rehabilitation approaches. The concept of oral frailty, oro-facial hypofunction, or oro-facial fitness should involve dental Patient Reported Outcomes (dPROs), and in this sense, there are only a few evidence-based rehabilitation procedures to improve oro-facial hypofunction besides prosthodontics. It must be considered that reduced neuroplastic capacity in old individuals might preclude a positive outcome of these strategies that might need to be accompanied by functional training and nutritional counseling

Effect of applying finishing products and sanding on the surface of marupa wood

The effect of applying cetol and varnish finishing products and sanding on the surface roughness and colour of marupa (Simarouba amara) wood was evaluated. Three coats of each product were applied and two sandpaper grits were used, 280 and 320). The analyzes were performed on untreated samples and between each coat of products in order to analyze the effect of sanding, the products and the number of coats. According to colorimetry, the L* value for the control treatment was 82.83 and the treatments reduced the L* to 61.70 on average for the cetol treatment and 77.09 for the varnish treatment, showing that the cetol darkened the wood more than the varnish. The yellowish and reddish pigmentations became more intense according to the positive values of Δa* and Δb*, especially after applying the cetol. The total colour variation ΔE average was 40.79 for the cetol treatment and 9.83 for the varnish treatment, confirming a much more significant colour change in the cetol treatment. Sanding with different grits did not significantly alter the surface colour. The product application made the wood surface smoother, and was noticeable from the second coat. Sanding reduced roughness on the wood surface, but the finishing product was the largest source of variation

Effect of measurement techniques and operators on measured deviations in digital implant scans.

OBJECTIVES To evaluate the effect of different measurement techniques and operators on measured deviations in in vitro implant scans. METHODS A 2-piece system that comprises a healing abutment (HA) and a scan body (SB) was mounted onto an implant at right first molar site of a polymethylmethacrylate mandibular dentate model. Model was digitized by using an industrial scanner (reference model scan, n=1) and an intraoral scanner (test scan, n=20). All standard tessellation language files were imported into a 3-dimensional analysis software and superimposed. Three operators with similar experience performed circle-based and point-based deviation analyses (n=20). Deviations measured with different techniques were compared with paired samples t-test within each operator, while the reliability of the operators was assessed by using F-tests for both technqiues (α=.05). RESULTS Point-based technique resulted in lower deviations than circle-based technique for all operators (P=.001) with to higher reliability among operators (ICC=.438, P=.001). The correlation among the operators was nonsignificant when circle-based technique was used (ICC=.114, P=.189). CONCLUSION Lower deviations were detected with the point-based technique. In addition, different operators' measurements had higher correlation when point-based technique was used compared with circle-based technique. CLINICAL SIGNIFICANCE Point-based technique may be preferred over circle-based technique for research studies on scan accuracy of implants, given its higher reliability. The accuracy of measured deviations may increase if the number of planes are increased, which can facilitate point generation at different surfaces of the scan body