Effect of Scanned Area and Operator on the Accuracy of Dentate Arch Scans with a Single Implant.

Studies have shown the effect of the operator and scanned areas on the accuracy of single implant scans. However, the knowledge on the scan accuracy of the remaining dental arch during single implant scans, which may affect the occlusion, is limited. The aim of this study was to investigate the effect of scanned areas and the operator on the scan accuracy of a dentate arch while scanning a single implant. A dentate model with an anterior implant was digitized with a laboratory scanner (reference scan). Three operators with similar experience performed 10 complete- and 10 partial-arch scans (left 2nd molar to right canine) with an intraoral scanner (TRIOS 3), and these scans were superimposed over the reference. The accuracy was analyzed at 22 points in complete-arch and at 16 points in partial-arch scans on 2nd molars and incisors. Data were evaluated with 2-way ANOVA and Tukey HSD tests (α = 0.05). The trueness of the total scanned area was higher in partial- than in complete-arch scans (p < 0.001). The trueness and precision of the scans were higher in the anterior site compared with the posterior in complete- (trueness: p ≤ 0.022, precision: p ≤ 0.003) and partial-arch (trueness: p ≤ 0.016, precision: p ≤ 0.016) scans of each operator and when the operator scan data were pooled. The complete-arch scan's precision was not influenced by the operator (p ≥ 0.029), whereas the partial-arch scans of operator 1 and 2 were significantly different (p = 0.036). Trueness was higher in partial- compared with complete-arch scans, but their precision was similar. Accuracy was higher in the anterior site regardless of the scan being a partial- or a complete-arch. The operator's effect on the accuracy of partial- and complete-arch scans was small.

Comparison of measured deviations in digital implant scans depending on software and operator.

OBJECTIVES: To investigate the effect of 3-dimensional (3D) analysis software and operator on the measured deviations in implant scans. MATERIAL AND METHODS: A combined healing abutment-scan body (CHA-SB) system was digitized with an industrial scanner (ATOS Core 80) to generate a master standard tessellation language file (MRM-STL) and an intraoral scanner (TRIOS 3) to generate 9 test-scan STL files, which were transferred into metrology-grade (Geomagic Control X, GX and GOM Inspect, GM) and nonmetrology-grade (Medit Link, ML) software for deviation analysis. Test-scan STLs were superimposed over MRM-STL and 2 planes passing through the center of the SB were generated. Distance deviations at 8 points on these planes were analyzed by two different operators with similar level of experience. Data were analyzed with analysis of variance and F tests (α=.05). RESULTS: Only model 1 (P=.049) analyzed by operator 2 showed significant differences among tested software, and the highest deviations were measured with GM (P≤.037). However, the difference in values measured with GX and ML was nonsignificant (P=.91). Operator correlation was high (ICC≥.712, P≤.011), except for models 1 (GM, ICC=-.335, P=.813), 2 (GM, ICC=.025, P=.468 and ML, ICC=-.013, P=.507), 6 (GM, ICC=-.085, P=.583), and 8 (GM, ICC=-.386, P=.85). CONCLUSION: The measured deviations in implant scans in all models, except for one, were similar among the tested software, regardless of the operator. The inter-rater reliability of operators while using tested 3D analysis software was overall high. When observed, low inter-rater reliability was mostly with only one of the metrology grade software. CLINICAL SIGNIFICANCE: Nonmetrology-grade 3D analysis software may be a suitable alternative to metrology-grade software to measure the deviations in digital implant scan body scans. When GOM metrology-software is used, measured deviations in implant scan body scans may vary more across operators.

Influence of 3D analysis software on measured deviations of CAD-CAM resin crowns from virtual design file: An in-vitro study.

OBJECTIVES: To evaluate a nonmetrology-grade and a metrology-grade 3D analysis software when measuring the deviations of computer-aided-design/ computer-aided-manufacturing (CAD-CAM) fabricated crowns from the virtual design file. MATERIALS AND METHODS: A right first molar on a mandibular dentate model was prepared and scanned with an intraoral scanner, i500 (Medit). A complete coverage crown was designed in standard tessellation language (STL) format and 20 resin crowns were fabricated with CAD-CAM. The crowns were then digitized using the same intraoral scanner (test-scans). Root mean square (RMS) method was used to evaluate the deviations between the test-scans and the design file of the crowns on 3 surfaces (overall, external, and internal) using a metrology-grade, Geomagic Control X (3D Systems) and a nonmetrology-grade, Medit Link (Medit) software. The data were analyzed with Welch two-sample t-tests to compare two software for the non-inferiority of the nonmetrology-grade software with a 50 µm threshold and the potential superiority of the metrology-grade software (α = 0.05). RESULTS: The Welch two-sample t-tests for the non-inferiority analysis showed that the differences between the nonmetrology-grade and the metrology-grade software were below the threshold of 50 µm for each surface tested (p <0.001). The differences between the two-tested software were nonsignificant for each surface analyzed when superiority was considered (p ≥.194). CONCLUSION: The nonmetrology-grade software performed similar to the metrology-grade software when analyzing the deviations of CAD-CAM crowns. Therefore, the nonmetrology-grade 3D analysis software may be considered for the deviation measurements of similar restorations. CLINICAL SIGNIFICANCE: The trueness of crowns after fabrication may affect their fit, and 3D analysis of trueness prior to the delivery appointment with the tested nonmetrology-grade software after fabrication may facilitate potential clinical adjustments and delivery of the crowns.

Congruence between the meshes of a combined healing abutment-scan body system acquired with four different intraoral scanners and the corresponding library file: An in vitro analysis.

OBJECTIVES: To investigate the congruence between the meshes of a combined healing abutment-scan body (CHA-SB) system acquired with four different intraoral scanners and the corresponding library file. MATERIAL AND METHODS: A CHA-SB was fixed to an implant at the right first molar position in a dentate mandibular model and digitized by using 4 different intraoral scanners (IOSs) [TRIOS 3 (T3), Omnicam (OC), Primescan (PS), and Virtuo Vivo (VV)] (n = 8) and an industrial grade optical scanner (ATOS Core 80) (n = 1) to generate standard tessellation language (STL) files of the test scans (CHA-SB-STLs) and the master reference model scan (MRM-STL). A reverse engineering software (Studio Geomagic X) was used to superimpose the proprietary library file of the CHA-SB over the generated STL files. Root mean square (RMS) values representing the deviations between the library file and the superimposed STL files were statistically analyzed by using 1-way ANOVA (α=0.05). Qualitative analysis of the deviations was performed by visual inspection. RESULTS: Differences between the congruence of the library file and the CHA-SB scans among different IOSs were nonsignificant (F = 1.619, df= 3, P = .207). The single best result was 29 ± 28.9 µm for OC, 30.8 ± 29.6 µm for VV, 35.6 ± 35.5 µm for T3, and 39.5 ± 39.2 µm for PS, which were all above the deviation value of the scan performed by using the industrial-grade scanner (23.2 ± 23.2 µm). CONCLUSION: The dimensional congruence between the library file and the STL file of the CHA-SB system scans was similar when intraoral scanners with different acquisition technologies were used to scan a model with an implant. CLINICAL SIGNIFICANCE: Scans of the tested intraoral scanners may result in crowns with similar positional accuracy, given the similarities in congruence of their scans with the library file.

The accuracy of single implant scans with a healing abutment-scanpeg system compared with the scans of a scanbody and conventional impressions: An in vitro study.

PURPOSE: To compare the accuracy of polyvinylsiloxane (PVS) impressions and intraoral scans when a healing abutment-scanpeg system (HASP) or a conventional scanbody (CSB) was used on a single implant. MATERIALS AND METHODS: A maxillary model with an implant (4.0 × 11 mm) (Neoss) and a CSB or an HASP (Neoss) was scanned by using a laboratory scanner (Ceramill Map 600; Amann Girrbach) (reference scans) and an intraoral scanner (Trios 3) (n = 10). PVS open-tray impressions were also made and stone casts of the model with a CSB were digitized with the laboratory scanner. Intraoral scanner and cast scans were superimposed to their reference scans. On superimposed scans, points were selected on HASP and CSB to calculate distance deviations (at points 1-4) and angular deviations (at points 5 and 6 on CSB and PVS, and 5-8 on HASP) between scans (trueness), and their variation (precision). The deviation data was analyzed with ANOVA and pairwise comparisons (trueness) with Tukey's adjustment, and F-tests (precision). RESULTS: At point 1, PVS had lower trueness than CSB (difference in means (DIMs) = 0.184 mm, p = 0.006) and HASP (DIMs = 0.122 mm, p = 0.042). At point 3, CSB had higher trueness than HASP (DIMs = 0.134 mm, p = 0.001). Angular deviations with PVS were higher than with CSB (DIMs = 0.6°, p = 0.013) and HASP (DIMs = 0.7°, p = 0.005). CSB had higher precision than PVS (p < 0.05). HASP had higher precision than PVS for distance (Point 1)(p < 0.001) and angular deviations (p < 0.05). Deviation differences within the HASP parts were not significant. CONCLUSION: The accuracy of intraoral scans and PVS impressions of an implant was similar. CLINICAL RELEVANCE: The combined healing abutment-scanpeg system and the conventional scanbody can be recommended for scans of anterior single implants with the intraoral scanner used.

Atratividade do sorriso: um método simples para melhorar a percepção visual do dentista: desenvolvimento e teste-piloto com estudantes de pós-graduação / Smile attractiveness: a simple method to improve the dentist's visual perception: development and pilot test with postgraduate students

Objetivos: melhorar a percepção do dentista sobre a atratividade do sorriso através de avaliações objetivas. Material e métodos: fotografias frontais de sorrisos (envolvendo a área dos caninos) foram aleatoriamente escolhidas e dispostas em dois sentidos verticais variados (nivelado, abaixo) numa guia personalizada contendo quatro molduras labiais do sorriso (fino, médio, grosso, invertido). Os aspectos que influenciam a atratividade do sorriso (PD = proporção dentária, PV = posicionamento vertical dentário, EL = espessura labial, FG = festonamento gengival) também foram incluídos e uma nota final geral atribuída ao sorriso geral (SG). Adicionalmente, o formulário do exercício continha a opção "existe um implante?" e "qual sua localização?". Todos os itens foram avaliados através de escalas de Likert. A prevalência de respostas foi calculada para cada item. O teste de Wilcoxon (alfa = 5%) foi usado para verificar a possibilidade de diferença de opinião entre os nivelamentos horizontais e para uma mesma moldura de sorriso. Os níveis de confiabilidade (concordância absoluta = ICC e responsividade = Cronbach alfa) também foram avaliados. Resultados: um teste-piloto foi conduzido com 16 estudantes. Trinta e duas combinações foto/moldura labial foram geradas e apresentadas de forma randomizada. A avaliação geral do sorriso ficou em: pobre (11/32), mediano (6/32), bom (15/32) e muito bom (1/32). O número de acertos da possível posição do implante foi 13 em 32 tentativas. Diferenças estatisticamente significativas entre os nivelamentos foram observadas nas situações 1/17 (p=0,0001), 13/29 (p=0,02), 2/18 (p=0,0002), 6/22 (p=0,0001), 14/30 (p=0,0001), 7/23 (p=0,01) e 15/31 (p=0,039). Os maiores coeficientes de ICC e Cronbach alfa foram vistos para o sorriso geral e FG. Conclusão: a percepção visual do dentista pode ser treinada mudando-se a moldura labial e o nivelamento vertical dos dentes e é influenciada pelo festonamento gengival. O teste se mostrou útil na verificação da atratividade do sorriso.

Objectives: to improve the perception of the dentist on the smile attractiveness through objective evaluations. Material and methods: frontal photographs of smiles (involving the canine area) were randomly chosen and arranged in two different vertical directions (leveled, below) in a personalized guide containing four lip architectures (thin, medium, thick, inverted). The aspects that infl uence the smile attractiveness (PD = dental proportion, PV = vertical tooth position, EL = lip thickness, GS = gingival scalloping) were also included and a general final score attributed to the general smile (SA). Additionally, the exercise form contained questions such as "is there an implant?" and "what is your location?". All items were assessed using Likert scales. The prevalence of responses was calculated for each item. The Wilcoxon test was used to verify the possibility of differences between the horizontal leveling for the same smile architecture. The reliability levels (absolute agreement = ICC and responsiveness = Cronbach alpha) were also evaluated. Results: a pilot test was conducted with 16 students. Thirty-two photos/lip architecture combinations were generated and presented at random. The overall smile rating was: poor (11/32), average (6/32), good (15/32), and very good (1/32). The number of positive responses for implant position was 13 in 32 trials. Statistically significant differences were observed in the combinations 1/17 (p=0.0001), 13/29 (p=0.02), 2/18 (p=0.0002), 6/22 (p=0.0001), 14/30 (p=0.0001), 7/23 (p=0.01) and 15/31 (p=0.039). The highest ICC and Cronbach alpha values were seen for the general smile attractiveness (SA) and GS. Conclusion: the visual perception can be trained by changing the lip architecture and vertical leveling of the teeth and is influenced by gingival scalloping. This test proved to be useful in verifying the smile attractiveness.

Immune Checkpoints in Leprosy: Immunotherapy As a Feasible Approach to Control Disease Progression.

Leprosy remains a health problem in several countries. Current management of patients with leprosy is complex and requires multidrug therapy. Nonetheless, antibiotic treatment is insufficient to prevent nerve disabilities and control Mycobacterium leprae. Successful infectious disease treatment demands an understanding of the host immune response against a pathogen. Immune-based therapy is an effective treatment option for malignancies and infectious diseases. A promising therapeutic approach to improve the clinical outcome of malignancies is the blockade of immune checkpoints. Immune checkpoints refer to a wide range of inhibitory or regulatory pathways that are critical for maintaining self-tolerance and modulating the immune response. Programmed cell-death protein-1 (PD-1), programmed cell death ligand-1 (PD-L1), cytotoxic T-lymphocyte-associated protein 4, and lymphocyte-activation gene-3 are the most important immune checkpoint molecules. Several pathogens, including M. leprae, are supposed to utilize these mechanisms to evade the host immune response. Regulatory T cells and expression of co-inhibitory molecules on lymphocytes induce specific T-cell anergy/exhaustion, leading to disseminated and progressive disease. From this perspective, we outline how the co-inhibitory molecules PD-1, PD-L1, and Th1/Th17 versus Th2/Treg cells are balanced, how antigen-presenting cell maturation acts at different levels to inhibit T cells and modulate the development of leprosy, and how new interventions interfere with leprosy development.

Immune checkpoints in leprosy: immunotherapy as a feasible approach to control disease progression

Leprosy remains a health problem in several countries. Current management of patients with leprosy is complex and requires multidrug therapy. Nonetheless, antibiotic treatment is insufficient to prevent nerve disabilities and control Mycobacterium leprae. Successful infectious disease treatment demands an understanding of the host immune response against a pathogen. Immune-based therapy is an effective treatment option for malignancies and infectious diseases. A promising therapeutic approach to improve the clinical outcome of malignancies is the blockade of immune checkpoints. Immune checkpoints refer to a wide range of inhibitory or regulatory pathways that are critical for maintaining self-tolerance and modulating the immune response. Programmed cell-death protein-1 (PD-1), programmed cell death ligand-1 (PD-L1), cytotoxic T-lymphocyte-associated protein 4, and lymphocyte-activation gene-3 are the most important immune checkpoint molecules. Several pathogens, including M. leprae, are supposed to utilize these mechanisms to evade the host immune response. Regulatory T cells and expression of co-inhibitory molecules on lymphocytes induce specific T-cell anergy/exhaustion, leading to disseminated and progressive disease. From this perspective, we outline how the co-inhibitory molecules PD-1, PD-L1, and Th1/Th17 versus Th2/Treg cells are balanced, how antigen-presenting cell maturation acts at different levels to inhibit T cells and modulate the development of leprosy, and how new interventions interfere with leprosy development.

Dispositivo acrílico simples para medir as alterações nos tecidos moles da maxila após procedimentos implantares ou restauradores protético-periodontais / A simple acrylic device to measure maxillary soft tissue alterations after implant and/or restorative periodontal and prosthetic procedures

Alterações nos tecidos moles, na zona estética, podem ocorrer por procedimentos restauradores associados ou não à Implantodontia. Os autores propuseram um dispositivo acrílico simples associado a uma sonda periodontal, para verificação destes níveis em todos os momentos do tratamento reabilitador. O dispositivo em questão também pode ser desenhado e confeccionado em qualquer sistema CAD/CAM.

Soft tissue changes in the esthetic zone can occur after restorative procedures associated or not to implant dentistry. The authors describe a simple acrylic device associated to a periodontal probe to verify those levels during all treatment procedure steps. Also, this device can be design and milled at any CAD/CAM system.

Efeito da soldagem híbrida (plasma + maçarico) na suavização da assinatura torque-ângulo em supraestruturas de COCR sobre minipilares de zircônia ­ parte 1 / Effect of hybrid soldering (plasma + gas torch) technique on suavization of torque-angle signatures at Co-Cr frameworks over zirconia mini-abutmets ­ part I

Objetivo: avaliar as desadaptações em supraestruturas de implantes e a curva de assinatura torque-ângulo dos parafusos protéticos nas condições monobloco e pós-soldagem. Material e métodos: uma base retangular de aço inox recebeu três implantes de hexágono externo (4,1 mm x 10 mm), onde foram parafusados minipilares de zircônia. Após o enceramento e inclusão, as supraestruturas foram fundidas em monobloco com uma liga de cobalto-cromo, e os cilindros foram numerados sequencialmente (1, 2 e 3). A leitura na interface supraestrutura/pilar foi realizada com um microscópio comparador (precisão de 1 µm), três vezes em cada cilindro. A tensão de torque nos parafusos foi medida com um torquímetro eletrônico odontológico (OsseoCare, Nobel Biocare). Depois, as supraestruturas foram seccionadas e soldadas a plasma (pontos de estabilização) e maçarico (preenchimento da área restante). Novamente, as desadaptações e assinaturas dos parafusos foram avaliadas pela mesma metodologia. Resultados: as médias de desadaptações foram maiores nas supraestruturas em monobloco (C1=3,5 µm; C2=0 µm; C3=31,2 µm) do que nas supraestruturas pós-soldagem (C1=3,0 µm; C2=2,9 µm; C3=18,1 µm). Dentro de cada condição, o teste de Kruskal-Wallis mostrou diferença estatisticamente significativa apenas para o cilindro 3 (monobloco: p < 0,00003 / pós-soldagem: p=0,008) em relação aos cilindros 1 e 2. Uma diferença estatisticamente significante foi encontrada apenas no C3, comparando as condições monobloco e pós-soldagem (teste t pareado, p=0,03). A assinatura dos parafusos se mostrou melhor na condição pós-soldagem. Conclusão: a fundição monobloco gera instabilidade na assinatura dos parafusos. A desadaptação nos parafusos protéticos de supraestruturas sobre minipilares de zircônia melhora após secção e soldagem híbrida.

Objective: to evaluate the misfi t at implant frameworks and the torque-angle signature curves at the prosthetic screws at one-piece and after soldering conditions. Material and methods: a stainless steel rectangular base received 3 external hex implants (4.1 x 10 mm) where zirconia mini-abutments were fastened. After wax-up and investing, the frameworks were one-piece cast with a Co-Cr alloy, and the prosthetic cylinders sequentially identified (1, 2, and 3). The misfit at the framework/abutment interface was measured with a microscope (reading error 1 µm) 3 times for each cylinder. The screw tension was investigated with an electronic torqued device (Osseocare, Nobel Biocare). After, the frameworks were sectioned and soldered with plasma (stabilization points) and gas torch (filling of the remaining areas). Again, the misfit and torque-angle signatures were measured as described. Results: mean misfit values were greater for one-piece castings (C1=3.5 µm; C2=0 µm; C3=31.2 µm) than after soldering (C1=3.0 µm; C2=2.9 µm; C3=18.1 µm). Within each condition, the Kruskal-Wallis test demonstrated a statistically significant difference only for C3 (one-piece casting: p < 0.00003 / after soldering: p=0.008) compared to C1 and C2. Between each condition, a significant difference was seen only for C3 in the one-piece and after soldering conditions (paired t test, p=0.03). The torque-angle signatures demonstrated a better behavior after soldering. Conclusion: one-piece castings provide instability at torque-angle signatures. Thus, the seating of the prosthetic abutments over the zirconia mini-abutments improves after sectioning and hybrid soldering.

Surface properties of multilayered, acrylic resin artificial teeth after immersion in staining beverages.

OBJECTIVE: To evaluate the effect of staining beverages (coffee, orange juice, and red wine) on the Vickers hardness and surface roughness of the base (BL) and enamel (EL) layers of improved artificial teeth (Vivodent and Trilux). MATERIAL AND METHODS: Specimens (n=8) were stored in distilled water at 37°C for 24 h and then submitted to the tests. Afterwards, specimens were immersed in one of the staining solutions or distilled water (control) at 37°C, and the tests were also performed after 15 and 30 days of immersion. Data were analyzed using 3-way ANOVA and Tukey's test (α=0.05). RESULTS: Vivodent teeth exhibited a continuous decrease (p<0.0005) in hardness of both layers for up to 30 days of immersion in all solutions. For Trilux teeth, similar results were found for the EL (p<0.004), and the BL showed a decrease in hardness after 15 days of immersion (p<0.01). At the end of 30 days, this reduction was not observed for coffee and water (p>0.15), but red wine and orange juice continuously reduced hardness values (p<0.0004). Red wine caused the most significant hardness changes, followed by orange juice, coffee, and water (p<0.006). No significant differences in roughness were observed for both layers of the teeth during the immersion period, despite the beverage (p>0.06). CONCLUSIONS: Hardness of the two brands of acrylic teeth was reduced by all staining beverages, mainly for red wine. Roughness of both layers of the teeth was not affected by long-term immersion in the beverages.

Surface properties of multilayered, acrylic resin artificial teeth after immersion in staining beverages

AbstractObjective To evaluate the effect of staining beverages (coffee, orange juice, and red wine) on the Vickers hardness and surface roughness of the base (BL) and enamel (EL) layers of improved artificial teeth (Vivodent and Trilux).Material and Methods Specimens (n=8) were stored in distilled water at 37°C for 24 h and then submitted to the tests. Afterwards, specimens were immersed in one of the staining solutions or distilled water (control) at 37°C, and the tests were also performed after 15 and 30 days of immersion. Data were analyzed using 3-way ANOVA and Tukey’s test (α=0.05).Results Vivodent teeth exhibited a continuous decrease (p<0.0005) in hardness of both layers for up to 30 days of immersion in all solutions. For Trilux teeth, similar results were found for the EL (p<0.004), and the BL showed a decrease in hardness after 15 days of immersion (p<0.01). At the end of 30 days, this reduction was not observed for coffee and water (p>0.15), but red wine and orange juice continuously reduced hardness values (p<0.0004). Red wine caused the most significant hardness changes, followed by orange juice, coffee, and water (p<0.006). No significant differences in roughness were observed for both layers of the teeth during the immersion period, despite the beverage (p>0.06).Conclusions Hardness of the two brands of acrylic teeth was reduced by all staining beverages, mainly for red wine. Roughness of both layers of the teeth was not affected by long-term immersion in the beverages.

Avaliação de massa e rugosidade superficial de pastilhas de Ti-6Al-4V com aplicação de nanopartículas de prata submetidos ao teste de escovação / Evaluation of mass and surface roughness of Ti-6Al-4V tablets with silver nanoparticles application submitted to brushing test

Este estudo teve por objetivo avaliar a variação da massa e rugosidade de pastilhas de Ti-6Al-4V com e sem aplicação superficial de nanopartículas de prata coloidal (BSafe®) de dimensões 1,5 cm; 0,5 cm e 0,2 cm, submetidas à teste de escovação e imersão pelo período experimental de 10 anos. No teste de escovação, quinze espécimes de Ti-6Al-4V (TE), quinze com B-Safe® (BE) e quinze de PMMA (PE) como controle foram subdivididos em três condições de escovação: dentifrício comum (DC), dentifrício experimental (DE) e controle com água destilada (H2O) por 200 mil ciclos em máquina de escovação. Os resultados foram submetidos ao teste ANOVA a 2 critérios (condição de escovação e ciclos) e teste de Tukey (α=0,05) para comparações múltiplas. Foi observada variação de massa apenas quando a condição de escovação foi DC nos espécimes do grupo PE e TE. Houve diferença estatisticamente significante nos valores da variação de rugosidade no grupo TE e PE quando a condição de escovação foi DC; no grupo BE, houve diferença quando a condição foi DC e DE, porém em DE houve redução dos valores médios. No teste de imersão, objetivando analisar a ação dos dentifrícios sem o atrito das cerdas, seis espécimes de Ti-6Al-4V (TI) e seis com B-Safe® (BI) foram subdivididos em três condições de imersão: DC, DE e H2O pelo período de 244 horas. Os resultados foram submetidos ao teste t de student pareado. Não foi observada diferença estatística entre as variações de massa e rugosidade de nenhum dos corpos de prova após o teste. Complementar aos ensaios, foi realizado um protocolo de desinfecção com terapia fotodinâmica com azul de metileno pelo período de 4 semanas nos espécimes escovados. Após todos os testes, foi realizada espectrometria de energia dispersiva de raios-X (EDS) para caracterização dos elementos químicos presentes nos espécimes, onde não se observou variações. Os resultados sugerem que o DE é mais indicado para utilização com implantes, enquanto DC apresenta um poder...

This study aimed to evaluate the variation of mass and roughness of Ti-6Al-4V tablets with and without superficial application of colloidal silver nanoparticles (BSafe®) with dimensions of 1,5 cm; 0,5 cm and 0,2 cm, submitted to brushing and immersion test for an experimental period of 10 years. For the brushing test, fifteen specimens of Ti-6Al-4V (TE), fifteen with B-Safe® (BE) and fifteen of PMMA (PE) as control were subdivided into three brushing conditions: normal toothpaste (DC), experimental toothpaste (DE) and control with distilled water (H2O) by 200 thousand cycles in brushing machine. The results were submitted to the ANOVA test on 2 criteria (brushing condition and cycles) and the Tukey test ((α= 0,05) for multiple comparisons. Mass variation was observed only when the brushing condition was DC, in PE and TE groups. Statistically significant difference was observed in the values of roughness variation on TE and PE group when the brushing condition was DC; in the BE group, there was difference when the condition was DC and DE, however in DE there was reduction of the average values. In the immersion test, aiming to analyze the action of toothpastes without the friction of the bristles, six specimens of Ti-6Al-4V (TI) and six with B-Safe® (BI) were subdivided into three immersion conditions: DC, DE and H2O for a period of 244 hours. The results were submitted to paired student t-test. No statistical difference was observed between mass and roughness variation for any of the specimens after the test. Additional to the tests, a disinfection protocol with photodynamic therapy with methylene blue was performed for a 4-week period on the brushed specimens. After all tests, Energydispersive X-ray Spectroscopy (EDS) was performed for characterization of the chemical elements present in the specimens, in which no variations were observed. The results suggest that DE is most suitable for use with implants, while DC has a higher abrasive power...

Lesão periférica de células gigantes recorrente: relato de caso / Recurrent peripheral giant cell lesion: case report

Lesão periférica de células gigantes é um processo proliferativo não neoplásico reativo à irritaçãolocal ou trauma. Apresenta-se como uma lesão bem circunscrita, que acomete a mucosa alveolar egengiva, podendo comprometer os tecidos ósseos adjacentes, causando mobilidade dentária. O examemicroscópico dessa lesão revela uma massa não encapsulada de tecido, contendo um grande númerode células do tecido conjuntivo e de células gigantes multinucleadas em um padrão estrutural,constituído de nódulos focais de células gigantes, separados por septos fibrosos. Tecido hemorrágico,hemossiderina, células inflamatórias e osso neoformado ou material calcificado também podem serencontrados ao longo do tecido conjuntivo. A associação de extensas lesões periféricas de célulasgigantes a fatores bucais ou sistêmicos ainda não é claramente estabelecida. O objetivo deste trabalhoé o de relatar um caso de lesão periférica de células gigantes recorrente. O correto diagnóstico eo adequado tratamento culminaram em resultados satisfatórios e completa resolução do caso, semindícios de recidivas. Este trabalho apresenta uma revisão atual sobre essa entidade, além de discutir sobre os fatores relacionados à sua etiologia.

Peripheral giant cell lesion is a non-neoplastic proliferative process reactive to the local that has anirritation or a trauma. Presents as well-circumscribed lesion confined to the alveolar and gingivalmucosa, may compromise the bone tissue adjacent causing tooth mobility. On histologic evaluation,the lesion is a noncapsulated mass of tissue containing a large number of young connective tissuecells and multinucleated giant cells in an architectural pattern of giant cells? focal nodules, separatedby fibrous septa. Hemorrhage, hemosiderin, inflammatory cells, and newly formed bone or calcifiedmaterial may also be seen throughout the cellular connective tissue. The association of large peripheralgiant cell?s lesions to oral or systemic factors is also unclear. The purpose of this work is to presenta case of peripheral giant cell?s lesion recurrence. The correct diagnosis and treatment culminatedin a totally satisfactory result and complete resolution of the case, without recurrences. This paperpresents a review on the current entity, and discusses the factors related to its etiology.

Dental manifestations in bariatric patients: review of literature.

The rate of bariatric surgery has significantly risen in the past decade as an increasing prevalence of extreme obesity can be observed. Although bariatric surgery is an effective therapeutic modality for extreme obesity, it is associated with risk factors affecting also oral health. Based on an overview of the current literature, this paper presents a summary of dental manifestations in bariatric patients. Bariatric surgeries are associated with an increased risk for gastro-esophageal reflux which in turn might account for the higher amount of carious and erosive lesions observed in bariatric patients. As a result, also dentin hypersensitivity might be observed more frequently. The current data indicate that recommended postsurgical meal patterns and gastric reflux might increase the risk for dental lesions, particularly in the presence of other risk factors, such as consumption of sweet-tasting foods and acidic beverages. Further research is needed to evaluate the correlation of bariatric surgery and the development of dental diseases.

Dental manifestations in bariatric patients: review of literature

The rate of bariatric surgery has significantly risen in the past decade as an increasing prevalence of extreme obesity can be observed. Although bariatric surgery is an effective therapeutic modality for extreme obesity, it is associated with risk factors affecting also oral health. Based on an overview of the current literature, this paper presents a summary of dental manifestations in bariatric patients. Bariatric surgeries are associated with an increased risk for gastro-esophageal reflux which in turn might account for the higher amount of carious and erosive lesions observed in bariatric patients. As a result, also dentin hypersensitivity might be observed more frequently. The current data indicate that recommended postsurgical meal patterns and gastric reflux might increase the risk for dental lesions, particularly in the presence of other risk factors, such as consumption of sweet-tasting foods and acidic beverages. Further research is needed to evaluate the correlation of bariatric surgery and the development of dental diseases.