Bond strength of composite resin/universal adhesive to dentin submitted to radiotherapy / Fuerza de unión de resina compuesta/adhesivo universal a dentina sometida a radioterapia

Aim: To evaluate the bond strength of a universal adhesive system to dentin submitted to radiotherapy. Materials and Methods: Sixty extracted human teeth were divided into two groups (n = 30): without radiotherapy (control); with radiotherapy, according to the adhesive protocol (n=15): ER-etch-and-rinse (acid + Single Bond Uni-versal); SE-self-etch (Single Bond Universal). The analyzes were shear bond strength (SBS) (n=10), failure pattern (n=10) and scanning electron microscopy (n=5). Data was analyzed by a two-way ANOVA (α =0.05). Results: The radiotherapy decreased SBS of the restorative material to dentin (p<0.0001). The ER protocol provided lower bond strength values (p<0.001). The predominant type of fracture without radiotherapy was mixed (SE), cohesive to the material (ER). Both protocols presented adhesive failures with radiotherapy. Teeth had a hybrid layer and long resin tags (without radiotherapy) and few tags (with radiotherapy). Conclusions: The SE adhesive mode favors the shear bond strength of resin to dentin in teeth submitted to radiotherapy.

Objetivo: Evaluar la fuerza de adhesión de un sistema adhesivo universal a la dentina sometida a radioterapia. Materiales y Métodos: Sesenta dientes humanos extraídos se dividieron en dos grupos (n = 30): sin radioterapia (control); con radioterapia, según protocolo adhesivo (n=15): ER-grabado y enjuague (ácido + Single Bond Universal); autograbado SE (Single Bond Universal). Los análisis ejecutados fueron resistencia al cizallamiento (SBS) (n=10), patrón de falla (n=10) y microscopía electrónica de barrido (n=5). Los datos se sometieron al test de ANOVA de dos vías (α =0,05). Resultados: La radioterapia disminuyó la SBS del material restaurador a la dentina (p<0,0001). El protocolo ER proporcionó valores de fuerza de unión más bajos (p<0,001). El tipo de fractura predominante sin radioterapia fue mixta (SE), cohesiva al material (ER). Ambos protocolos presentaron fallas adhesivas con radioterapia. Los dientes tenían una capa híbrida y colas de resina largas (sin radioterapia) o pocas colas de resina (con radioterapia). Conclusión: El modo adhesivo SE favorece la resistencia al corte de la resina a la dentina en dientes sometidos a radioterapia.

Effect of aging and cementation systems on the bond strength to root dentin after fiber post cementation

Abstract This study evaluated the effect of aging and cementation of fiber posts using glass ionomer and resin cements on push-out bond strength, failure mode, and resin tag formation. One hundred and twenty bovine incisors were used. After post-space preparation, the specimens were randomly allocated into 12 groups (n = 10) according to the cementation system used: GC - GC Gold Label Luting & Lining); RL - RelyX Luting 2; MC - MaxCem Elite; RU - RelyX U200 and the aging periods (24 hours, 6 months, and 12 months). Slices from the cervical, middle, and apical thirds were obtained and analyzed by push-out bond strength test and confocal laser scanning microscopy. One-way ANOVA and Tukey's post-hoc test was used at a significance level of 5%. For the push-out bond strength test, no differences among GC, RU, and MC in the cervical and middle thirds were observed, regardless of the period of storage (P > 0.05). In the apical third, GC and RU showed similar bond strength but higher than other groups (P > 0.05). After 12 months, GC showed the highest bond strength (P < 0.05). Bond strength to post-space dentin decreased over time, regardless of the cementation system used. Cohesive failure was the most frequent, regardless of the period of storage, cementation system, and post-space third. Tag formation was similar among all groups. After 12 months, GC showed the highest bond strength values.

Resumo Avaliar o efeito do envelhecimento e sistemas de cimentação usando ionômero de vidro e cimentos resinosos na resistência de união à dentina após a cimentação do pino de fibra. Cento e vinte incisivos bovinos foram utilizados. Após o preparo do pós-espaço, os corpos de prova foram distribuídos aleatoriamente em 12 grupos (n = 10) de acordo com o período de envelhecimento (24 horas, 6 meses e 12 meses) e o sistema de cimentação utilizado: GC - cimento de ionômero de vidro (GC Gold Label Cimentação e Revestimento); RL - RelyX Luting 2; MC - MaxCem Elite; RU - RelyX U200. Cortes dos terços cervical, médio e apical foram obtidos e analisados por teste de resistência de união push-out e microscopia confocal de varredura a laser. ANOVA one-way e teste de Tukey foi usado a um nível de significância de 5%. Para o teste de resistência de união, não foram observadas diferenças entre GC, RU e MC nos terços cervical e médio, independentemente do período de armazenamento (P > 0,05). No terço apical, GC e RU apresentaram resistência de união semelhante, porém superior aos demais grupos (P > 0,05). Após 12 meses, o GC apresentou a maior resistência de união (P < 0,05). A resistência de união à dentina no espaço para pino diminuiu ao longo do tempo, independentemente do sistema de cimentação utilizado. A formação de tags foi semelhante entre todos os grupos. Após 12 meses, o GC apresentou os maiores valores de resistência de união.

The effects of TiO2 nanotubes on bond strength and radiopacity of a self-adhesive resin cement in self-curing mode / Os efeitos de nanotubos de TiO2 na resistência de união e radiopacidade de um cimento resinoso auto-adesivo no modo auto-polimerizável

Objective: The aim of this in vitro study w as t o analyze the influence of the titanium dioxide nanotubes i n a self-cure mode polymerization of a dual resin luting agent through push out bond strength and radiopacity tests. Material and Methods: After mixed with a commercial du al self-adhesive resin cement, three concentrations o f tit anium dioxide nanotubes (0.3, 0.6, and 0.9% by weight) we re analyzed in self-curing mode. T he bond strength to bovine root dentin and fi berglass posts was assessed with the push out bond str ength t est and was evaluated in three thirds (cervical, middle and apical) (n=10), followed by failure mode analysis (SEM), and the ISO standard 9917-2 was followed for radiopacity test (n=10). Data were statistically analyzed by one-way ANOVA test, followed by Tukey's test (α=0.05). Results: Reinforced self-adhesive resin cement with 0.6% titanium dioxide nanotubes showed significant difference compared to the control gr oup for push out test (p=0.00158). The modified groups did not s how significant difference among thirds (p=0.782). Radiopacity sh owed higher value for group w ith 0.9% titanium dioxide nanotubes in comparison w ith control group (p<0.001). Conclusion: The addition of titanium dioxide nanotubes to a self-adhesive resin cement increased the bond strength to dentin and radiopacity values in the self-cure polymerization mode (AU)

Objetivo: O objetivo deste estudo in vitro foi analisar a influência de nanotubos de dióxido de titânio na polimerização química de um agente cimentante resinoso dual através de testes de resistência à união e radiopacidade. Material e Métodos: Após misturado com um cimento resinoso auto-adesivo comercial, três concentrações de nanotubos de dióxido de titânio (0,3, 0,6 e 0,9% em peso) foram analisadas. A resistência da união para a dentina da raiz bovina e os pinos de fibra de vidro foi avaliada pelo teste de push-out e avaliada em três terços (cervical, médio e apical) (n = 10), seguido pelo análise de modo de falha (MEV) e a norma ISO 9917-2 foi seguido para teste de radiopacidade (n = 10). Os dados foram analisados estatisticamente pelo teste ANOVA um fator seguido do teste de Tukey (α = 0,05). Resultados: O cimento resinoso auto-adesivo reforçado com nanotubos de dióxido de titânio a 0,6% mostrou diferença significativa em comparação com o grupo controle para teste de push-out (p=0,00158). Os grupos modificados não mostraram diferença significativa entre os terços (p=0,782). A radiopacidade mostrou maior valor para o grupo com nanotubos de dióxido de titânio 0,9% em comparação com o grupo controle (p<0,001). Conclusão: A adição de nanotubos de dióxido de titânio a um cimento resinoso auto-adesivo aumentou a os valores de resistência de união à dentina e radiopacidade no modo de polimerização química do agente cimentante (AU)

Pulp chamber temperature rise in light-cure bonding of brackets with and without primer, in intact versus restored teeth

ABSTRACT Objective: To evaluate the pulp chamber temperature rise (PCTR) in light-cure bonding of brackets with and without primer, in intact and restored mandibular central incisors (M1), maxillary first premolars (Mx4), and mandibular third molars (M8). Material and Methods: Ninety human teeth were included: M1 (n=30), Mx4 (n=30), and M8 (n=30). Light-cure bonding of brackets was performed in intact (n=60) and restored (n=30) teeth, with primer (n=60) or without (n=30) primer. PCTR was defined as the difference between initial (T0) and peak temperatures (T1), recorded with a thermocouple during light-cure bonding. Differences on PCTR between bonding techniques (primer vs. no primer), teeth types (M1 vs. Mx4 vs. M8), and teeth condition (intact vs. restored) were estimated by ANCOVA, with α=5%. Results: PCTR was significantly higher with the use of primer (2.05 ± 0.08oC) than without primer (1.65 ± 0.14oC) (p=0.02), and in M1 (2.23 ± 0.22oC) compared to Mx4 (1.56 ± 0.14oC) (p<0.01). There was no difference in the PCTR in M8 (1.77 ± 0.28oC) compared to M1 or Mx4 (p>0.05), and no difference between intact (1.78 ± 0.14oC) and restored (1.92 ± 0.08oC) teeth (p=0.38). There was no influence of dentin enamel thickness in the PCTR (p=0.19). Conclusion: PCTR was higher in light-cure bonding of brackets with primer, especially in M1. Light-cure bonding seems less invasive without primer.

RESUMO Objetivo: Comparar o aumento na temperatura da câmara pulpar (ATCP) na colagem de braquetes com fotoativação usando ou não primer, em dentes hígidos versus dentes restaurados, em incisivos centrais inferiores (ICI), primeiros pré-molares superiores (1PMS) e terceiros molares inferiores (3MI). Métodos: Foram incluídos noventa dentes humanos: ICI (n=30), 1PMS (n=30) e 3MI (n=30). A colagem de braquetes com fotoativação foi realizada em dentes hígidos (n=60) ou dentes restaurados (n=30), com primer (n=60) ou sem (n=30) primer. O ATCP foi definido como a diferença entre as temperaturas inicial (T0) e máxima (T1) registradas com um termômetro durante a colagem com fotoativação. As diferenças no ATCP entre as técnicas de colagem (com primer vs. sem primer), diferentes dentes (ICIvs.1PMSvs.3MI) e condição dos dentes (hígidos vs. restaurados) foram estimadas por ANCOVA, com α=5%. Resultados: O ATCP foi significativamente maior com o uso de primer (2,05 ± 0,08oC) do que sem primer (1,65 ± 0,14oC) (p=0,02), e no ICI (2,23 ± 0,22oC) do que no 1PMS (1,56 ± 0,14oC) (p<0,01). Não houve diferença no ATCP do 3MI (1,77 ± 0,28oC) em comparação com ICI ou 1PMS (p>0,05), e não houve diferença entre dentes hígidos (1,78 ± 0,14oC) e restaurados (1,92 ± 0,08oC) (p=0,38). Não houve influência da espessura da dentina e do esmalte no ATCP (p=0,19). Conclusão: O ATCP foi maior na colagem de braquetes com fotoativação usando primer, principalmente no ICI. A colagem com fotoativação parece ser menos invasiva sem primer.

Evaluating changes in the color and luminosity of dental enamel after orthodontic treatment: A clinical study

Abstract The aims of this clinical study were to evaluate the Color change - ΔE (based on spectrophotometry and visual analysis) and luminosity - L* (based on spectrophotometry) of dental enamel surface (after orthodontic treatment) around the area where orthodontic brackets were fixed, based on different cementing materials such as a resin (R group) and resin-modified glass ionomer cement (RMGIC group). The split-mouth study initially comprised 14 patients. Orthodontic brackets were fixed to the upper central incisors with resin or RMGIC. The color of the buccal surface of each tooth was measured through spectrophotometry and visual examination before the bracket-fixation process. Four individuals were excluded during the follow-up; thus 10 patients were evaluated (n=10). Brackets were removed after 12 months of orthodontic treatment, tooth color measurement and visual examination were performed again, and Adhesive Remaining Index (ARI) was also measured. ΔE and L* results were subjected to Student's t-test and by repeated-measures analysis of variance, respectively (α=0.05). ARI data were analyzed in percentages. There was statistically significant difference in ΔE between groups; the R group showed statistically higher values of L* after orthodontic treatment. ARI of 2 and 3 prevailed in the RMGIC group, whereas the R group presented 0 and 1. After orthodontic treatment, the RMGIC group presented smaller changes in ΔE, and the increase in the white scale was observed on the enamel surface around the area where brackets were fixed in the R group. The visual analysis did not show color change on the evaluated teeth.

Resumo Os objetivos deste estudo clínico foram avaliar a alteração de cor - ΔE (baseada em espectrofotometria e análise visual) e luminosidade - L* (baseada em espectrofotometria) da superfície do esmalte dentário (após tratamento ortodôntico) ao redor da área onde os braquetes ortodônticos foram fixados, com base em diferentes materiais de cimentação, como resina (grupo R) e cimento de ionômero de vidro modificado por resina (grupo RMGIC). Estudo boca dividida foi inicialmente composto por 14 pacientes. Os braquetes ortodônticos foram fixados nos incisivos centrais superiores com resina ou RMGIC. A cor da superfície vestibular de cada dente foi mensurada por espectrofotometria e avaliada por exame visual antes do processo de fixação dos braquetes. Quatro indivíduos foram excluídos durante o acompanhamento; assim, 10 pacientes foram avaliados (n=10). Os braquetes foram removidos após 12 meses de tratamento ortodôntico, a mensuração da cor do dente e o exame visual foram realizados novamente, e o Índice de Remanescente do Adesivo (IRA) também foi mensurado. Os resultados ΔE e L* foram submetidos ao teste t de Student e à análise de variância para medidas repetidas, respectivamente (α=0.05). Os dados do ARI foram analisados em porcentagens. Houve diferença estatisticamente significativa no ΔE entre os grupos; o grupo R apresentou valores estatisticamente maiores de L* após o tratamento ortodôntico. O IRA 2 e 3 prevaleceu no grupo RMGIC, enquanto o grupo R apresentou 0 e 1. Após o tratamento ortodôntico, o grupo RMGIC apresentou menores alterações no ΔE e o aumento da escala branca foi observado na superfície do esmalte ao redor da área onde os braquetes foram fixados no grupo R. A análise visual não mostrou mudança de cor nos dentes avaliados.

Exposure to lipopolysaccharide and calcium silicate-based materials affects the behavior of dental pulp cells

Abstract This study assessed the cell viability, cytokine production, and mineralization potential of human dental pulp cells (hDPCs) after exposure to lipopolysaccharide (LPS) and application of calcium silicate-based materials (CSBM). Characterization of the CSBM was performed by infrared spectroscopy (n = 3). Extracts of Bio-C Repair, Biodentine, Cimmo HD, and MTA Repair HP were prepared and diluted (1:1, 1:4, and 1:16). Culture of hDPCs was established and treated or not with 1 µg/mL of LPS from Escherichia coli for 7 days. MTT assay was used to assess cell viability at 24, 48, and 72 h (n = 6). Alkaline phosphatase (ALP) activity was assayed on day 7 (n = 4). Il-10 and TNF-α were quantified by ELISA at 24 h (n = 6). Data were analyzed by ANOVA and Tukey's test (α = 0.05). Cell viability of LPS-activated hPDCs was higher than untreated control in 48 and 72 h (p < 0.05). Differences between non-treated and LPS-activated hPDCs were observed for Biodentine and Cimmo HP (p < 0.05). The CSBM influenced the cell viability (p < 0.05). ALP activity was higher in LPS-activated hDPCs (p < 0.05). No changes in the concentration of TNF-α were observed between groups (p > 0.05). The CSBM increased the Il-10 production (p < 0.05). LPS-activated hDPCs presented increased cell viability and ALP activity. The CSBM showed mild toxicity and was able to enhance the cell viability and mineralization potential of untreated and LPS-activated hDPCs. The CSBM also induced anti-inflammatory mechanisms without compromising pro-inflammatory ones.

Resumo Este estudo avaliou a viabilidade celular, produção de citocinas e potencial de mineralização de células da polpa dentária humana (hDPCs) após exposição a lipopolissacarídeo (LPS) e aplicação de materiais à base de silicato de cálcio (CSBM). A caracterização do CSBM foi realizada por espectroscopia (n = 3). Extratos de Bio-C Repair, Biodentine, Cimmo HD e MTA Repair HP foram preparados e diluídos (1: 1, 1: 4 e 1:16). A cultura de hDPCs foi estabelecida e tratada ou não com 1 µg / mL de LPS de Escherichia coli por 7 dias. O ensaio de MTT foi usado para avaliar a viabilidade celular em 24, 48 e 72 h (n = 6). A atividade da fosfatase alcalina (ALP) foi avaliada no dia 7 (n = 4). Il-10 e TNF-α foram quantificados por ELISA em 24 h (n = 6). Os dados foram analisados ​​por ANOVA e teste de Tukey (α = 0,05). A viabilidade celular das hPDCs ativados por LPS foi maior do que o controle não tratado em 48 e 72 h (p <0,05). Diferenças entre hPDCs não tratados e ativados por LPS foram observados para Biodentine e Cimmo HP (p < 0,05). Os CSBM influenciaram na viabilidade celular (p <0,05). A atividade de ALP foi maior em hDPCs ativadas por LPS (p <0,05). Não foram observadas alterações na concentração de TNF-α entre os grupos (p> 0,05). Os CSBM aumentaram a produção de Il-10 (p < 0,05). Os hDPCs ativados por LPS apresentaram um aumento na viabilidade celular e atividade ALP. Os CSBM apresentaram toxicidade moderada e foram capazes de aumentar a viabilidade celular e o potencial de mineralização de hDPCs não tratados e ativados por LPS. Os CSBM também induziram mecanismos anti-inflamatórios sem comprometer os pró-inflamatórios.

Response of periodontal ligament stem cells to lipopolysaccharide and calcium silicate-based materials

Abstract This study was conducted to assess the in vitro response of human periodontal ligament stem cells (hPDLSCs) to bacterial lipopolysaccharide (LPS) activation and application of three calcium silicate-based materials (CSBM): Bio-C Sealer, MTA Fillapex and Cimmo HP. Characterization of the CSBM was performed by FTIR (n = 3). Extracts of Bio-C Sealer, MTA Fillapex and Cimmo HP were prepared and diluted (1:1, 1:4 and 1:16). Culture of hPDLSCs was established and treated or not with LPS from Escherichia coli (1 µg/mL) for 7 days. MTT assay was used to assess cell viability at 24, 48 and 72 h (n = 9). Alkaline phosphatase (ALP) activity was indirectly assayed at day 7 (n = 5). TNF-α and Il -1 0 cytokines were quantified by ELISA at 24h-cell supernatants (n = 6). Data were analyzed by ANOVA and Tukey's test (α = 0.05). The cell viability of the LPS-activated hPDLSCs were higher than untreated control (p < 0.05). The application of CSBM affected the cell viability of untreated and LPS-activated cells (p < 0.05). ALP activity was higher for Bio-C Sealer and Cimmo HP in untreated and LPS-activated cells, respectively (p < 0.05). Application of CSBM normalized the TNF-α secretion in the LPS-activated cells (p < 0.05). Only MTA Fillapex in untreated hPDLSCs presented higher values of Il -1 0 (p < 0.05). Taken collectively, the results suggests that the simulation of the inflammatory process by LPS affect the in vitro response the hPDLSCs to the application of the CSBM.

Resumo Este estudo objetivou avaliar a resposta in vitro de células-tronco do ligamento periodontal humano (hPDLSCs) à ativação por lipopolissacarídeo bacteriano (LPS) e aplicação de três materiais à base de silicato de cálcio (CSBM): Bio-C Sealer, MTA Fillapex e Cimmo HP. A caracterização dos CSBM foi realizada por FTIR (n = 3). Extratos de Bio-C Sealer, MTA Fillapex e Cimmo HP foram preparados e diluídos (1:1, 1: 4 e 1:16). A cultura de hPDLSCs foi estabelecida e tratada ou não com 1 µg / mL de LPS de Escherichia coli por 7 dias. O ensaio de MTT foi usado para avaliar a viabilidade celular em 24, 48 e 72 h (n = 9). A atividade de ALP foi avaliada indiretamente no dia 7 (n = 5). As citocinas TNF-α e Il-10 foram quantificadas por ELISA em sobrenadantes de células em 24h (n = 6). Os dados foram analisados por ANOVA e teste de Tukey (α = 0,05). A viabilidade celular das hPDLSCs ativados por LPS foi maior do que o controle (p <0,05). A aplicação dos CSBM afetou a viabilidade celular de células ativadas ou não por LPS (p <0,05). A atividade de ALP foi maior para Bio-C Sealer e Cimmo HP em células não ativadas e ativadas por LPS, respectivamente (p <0,05). A aplicação dos CSBM normalizou a secreção de TNF-α nas células ativadas por LPS (p <0,05). Apenas o MTA Fillapex em hPDLSCs não ativadas apresentou valores mais elevados de Il-10 (p <0,05). Em conclusão, os resultados sugerem que a simulação do processo inflamatório por LPS afetou a resposta in vitro de células-tronco do ligamento periodontal e de materiais à base de silicato de cálcio.

Diametral tensile strength of conventional glass ionomer cements with modified powder ratio for uses in atraumatic restorative treatment / Resistência à tração diametral de cimentos de ionômero de vidro convencionais modificados na razão de pó para uso em tratamento restaurador atraumático

ABSTRACT Objective: To identify the diametral tensile strength of Brazilian brands of conventional glass ionomer cements (GIC) when modified powder ratio in their composition compared to each other, and with high viscosity glass ionomer cement for Atraumatic Restorative Treatment (ART). Methods: Experimental study with five groups (n=10 each) and specimens (2.5 mm in height and 5.0 mm in diameter), considering G1 (Maxxion R-MR), G2 (Vidrion R-VR) and G3 Vitro molar (VM-control) according to manufacturer recommending powder/liquid (1:1), G4 (MR) and G5 (VR) plus powder (2:1). The specimens were stored in an oven at 37 ± 1 ° C for 1 day. Diametral Tensile Test was performed by the Instron model 4444. Means differences were tested by Student´s T-Test (α = 5%). Results: There significant differences were in the means (standard deviation) of diametral tensile strength of MR (1:1) 4.24 (±1.47) and MR (2:1), 5.74 (±1.51) (p=0.039) and VR (1:1) 4.50 (±1.27) and VR (2:1) 6.20 (±1.89) (p=0.029). When comparing MR and VR (2:1) with MV (1:1) 4.82 (±1.17), VR 2: 1, 6.20 (±1.89) showed significant differences (p=0.0336). Conclusion: There was a significant increase in the means of diametral tensile strength of Brazilian brands conventional GICs when powder increment, approaching the performance observed by the high viscosity GIC.

RESUMO Objetivo: Identificar a resistência à tração diametral de marcas nacionais de cimentos de ionômero de vidro (CIV) convencionais quando acrescidos de pó em sua composição comparados entre si e com cimento de ionômero de vidro de alta viscosidade para Tratamento Restaurador Atraumático (TRA). Métodos: Pesquisa experimental com cinco grupos (n=10 cada) e confeccionados corpos de prova (2,5 mm de altura e 5,0 mm de diâmetro), considerando G1 (Maxxion R/FGM-MR), G2 (Vidrion R/SS White-VR) e G3 Vitro molar (DFL-VM-controle) manipulados segundo fabricante pó/líquido (1:1), G4 (MR) e G5 (VR) acrescidos de pó (2:1). Os espécimes foram armazenados em estufa a 37 ± 1° C por 1 dia. Teste de Tração Diametral foi realizado pelo equipamento Instron modelo 4444. As diferenças das médias foram testadas pelo Test T de Student (α=5%). Resultados: Foram encontradas diferenças significativas das médias (desvio-padrão) de resistência à tração diametral de MR (1:1) 4,24 (±1,47) e MR (2:1), 5,74(±1,51) (p=0,039) e VR (1:1) 4,50 (±1,27) e VR (2:1) 6,20(± 1,89) (p=0,029). Quando da comparação entre MR e VR (2:1) com VM (1:1) 4,82(±1,17), VR 2:1, 6,20 (±1,89) apresentou média superior e significante (p=0,0336). Conclusão: Observou-se aumento significativo nas médias de resistência mecânica à tração diametral dos CIVs convencionais nacionais a partir do incremento de pó, aproximando-se do desempenho observado pelo CIV de alta viscosidade.

Cytotoxicity of Reparative Endodontic Cements on Human Periodontal Ligament Stem Cells

ABSTRACT Objective To compare the cytotoxicity of commercial reparative endodontic cements on human periodontal ligament stem cells (hPDLSCs). Material and Methods The culture of hPDLSCs was established. Cell density was set at 2 × 104 cells/well in 96-well plates. Extracts of Biodentine, Bio-C Repair, Cimmo HD, MTA Repair HP and White MTA were prepared. Then, the extracts were diluted (pure, 1:4 and 1:16) and inserted into cell-seeded wells for 24, 48, and 72 h to assess cell viability through MTT assay. hPDLSCs incubated with culture medium alone served as a negative control group. Data were analyzed by Two-Way ANOVA and Tukey's test (α=0.05). Results At 24 h, pure extract of MTA Repair HP and Biodentine 1:16 presented higher cell viability compared to control. Lower cell viability was found for pure extract of Cimmo HD, MTA Repair HP 1:4 and 1:16, and White MTA 1:16. At 48 h, pure extract of Bio-C Repair and MTA Repair HP presented higher cell viability compared to control. At 72 h, only the pure extract of MTA Repair HP led to higher cell proliferation compared to control. Conclusion Biodentine, Bio-C Repair and MTA Repair HP were able to induce hPDLSCs proliferation. Cimmo HD and White MTA were found to be mostly cytotoxic in hPDLSCs.

Impact of economic factors and knowledge translation on public procurement for dental adhesive systems

Abstract: This study aimed to screen the public procurement for dental adhesives in a public health system and evaluate the variables associated with the type and cost of purchased materials. A time series was conducted with secondary data collated from the Brazilian Databank of Healthcare Prices (BDHP). All public procurements for adhesive systems registered from 2010 to 2019 were collated. The frequency of purchase was described, and a multiple linear regression model was used to assess the influence of unit price on predictor variables. Multinomial logistic regression was conducted to describe the influence of selected variables on the probability of purchase for different classes of adhesive systems. A total of 2,752 purchases were analyzed, and the total cost of these materials reached US$ 7,022,659.00 in the 10 analyzed years. The 3-step Etch & Rinse adhesives corresponded to 45.63% of the processes, with increased probability of being purchased over time. The process conducted by public universities in recent years, using the auction modality, presented lower unit prices. The year of purchase, the type of institutions, the institution's location, and the procurement modality influenced the procurement process. The performed analyses contribute to the understanding of the variables associated with the procurements for adhesive systems, providing valuable information for rationalizing public expenditure and for implementing evidence-based practices to guarantee cost-effective and clinically effective procedures for users of the Brazilian public healthcare system.

Durability of bond strength to dentin using two universal adhesives in different etching modes

Aim. To evaluate the bond durability of two universal adhesives; mild and ultra-mild in both etch-and-rinse and self-etch modes after simulated in-vitro degradation by long-term water storage or thermocycling. Methods. A total of 144 specimens were used in this study; 120 specimens (prepared from 30 teeth) for microshear bond strength testing and fracture mode assessment, and 24 specimens for scanning electron microscopic evaluation (prepared from 24 teeth). Specimens were prepared from 54 recently extracted caries free third molars and randomly divided into 12 groups, according to the adhesive treatment (All Bond or Scotchbond Universal), etching mode (etch-andrinse or self-etch) and aging method (thermocycling or water storage). Each tooth was sectioned mesio-distally into two halves exposing free dentin surface for bonding where dentin substrate 1 mm below the dentino-enamel junction was used. After adhesive application and composite build up, specimens were tested in shear mode after storing in distilled water at 37˚C for 24 hours or 1 year, or after being thermocycled between 5 and 55 °C for 10,000 cycles (n=10). Microshear bond strength (µSBS) was tested using a universal testing machine. Adhesive-dentin interface was examined using scanning electron microscope (SEM) (n=2). Data were analyzed using 3 way AN0VA and pairwise comparisons was performed using Bonferroni correction at significance level of α ≤0.05. Results. Statistical analysis revealed non-significant difference for etching mode in both adhesives (p=0.596). After aging, the bond strength was only reduced in Scotchbond Universal after one year of water storage in both modes (p<0.001). SEM evaluation revealed intact hybrid layer and longer resin tags for etch-and-rinse mode than selfetch mode of both adhesives. Conclusion. The bond strength of universal adhesives is not affected by the etching mode, however its durability was shown to be material dependent

Calcium silicate-based cements affect the cell viability and the release of TGF-β1 from apical papilla cells

Abstract This study investigated the cytotoxicity and release of Transforming Growth Factor Beta 1 (TGF-β1) from cultured human apical papilla cells (APCs) after application of four bioactive materials. Culture of APCs was established and used for cytotoxic and quantitative assays. Extracts of Biodentine, Bio-C Repair, MTA Repair and White MTA were prepared and diluted (1, 1:4 and 1:16) and used for MTT assays up to 72 h. Total TGF-β1 was quantified by ELISA. Data were analyzed by ANOVA and Tukey's test (α = 0.05). For Biodentine, at 24 h and 48 h, cell viability was lower than control (p < 0.05). At 72 h, only undiluted extract of Biodentine were cytotoxic (p < 0.05). At 24 h, a cytotoxic effect was found for undiluted and 1:4 dilution of Bio-C Repair (p < 0.05). At 48 h, however, Bio-C Repair at 1:4 and 1:8 dilution showed higher cell viability (p < 0.05). At 24 and 48 h, the cell viability for undiluted MTA Repair were higher than control (p < 0.05). For White MTA, at 24 and 48 h, all dilutions were cytotoxic (p < 0.05). All cements led to reduced release of total TGF-β1 from the APCs (p < 0.05). In conclusion, cell viability varied depending on the material and dilution. Only Bio-C repair and MTA repair led to higher cell viability of APCs. All materials induced a decrease in the release of total TGF-β1 from the APCs.

Resumo Este estudo investigou a citotoxicidade e liberação do Fator de Crescimento Transformador Beta 1 (TGF-β1) em células da papila apical humana (APCs) cultivadas após a aplicação de quatro materiais bioativos. A cultura de APCs foi estabelecida e usada para ensaios citotóxicos e quantitativos. Extratos de Biodentine, Bio-C Repair, MTA Repair e White MTA foram preparados e diluídos (1, 1: 4 e 1:16) e usados para ensaios de MTT por até 72 h. O TGF-β1 total foi quantificado por ELISA. Os dados foram analisados por ANOVA e teste de Tukey (α = 0,05). Para o Biodentine, em 24 h e 48 h, efeito citotóxico foi observado (p <0,05). Em 72 h, apenas o extrato não diluído de Biodentine teve efeito citotóxico (p <0,05). Em 24 h, valores mais baixos de viabilidade celular foram encontrados para o extrato não diluído e diluidi 1:4 de Bio-C Repair (p <0,05). Em 48 h, no entanto, Bio-C Repair na diluição 1:4 e 1:8 mostrou maior viabilidade celular (p <0,05). A viabilidade celular para MTA Repair não diluído em 24 e 48 h foi maior que o controle (p <0,05). Para White MTA, às 24 e 48 h, a viabilidade celular em todas as diluições foram citotóxicas (p <0,05). Todos os cimentos levaram à redução da liberação de TGF-β1 total das APCs (p <0,05). Em conclusão, a viabilidade celular variou dependendo do material e da diluição. Biodentine, Bio-C Repair e MTA Repair levaram a uma maior viabilidade celular de APCs. Todos os materiais induziram uma diminuição na liberação de TGF-β1 total das APCs.

Propiedades y aplicación clínica de los ionómeros de vidrio de alta densidad disponibles en Lima-Perú / Properties and clinical application of high density glass ionomers available in Lima-Peru

El objetivo de la revisión fue conocer las propiedades y la aplicación clínica de los diferentes ionómeros de vidrio de alta densidad disponibles en Lima-Perú. Se realizó una revisión de la literatura científica desde enero 2010 hasta diciembre 2019 acerca de los ionómeros de vidrio de alta densidad. Esta revisión se realizó en las bases de datos SciELO, Pubmed y Google Scholar. Los descriptores para realizar la búsqueda fueron: cementos de ionómero de vidrio, ionómeros de vidrio de alta densidad y propiedades físicas, las combinaciones entre ellos y su equivalente en inglés. Se seleccionaron finalmente 40 artículos que cumplieron con los criterios de inclusión. Dentro de las marcas de ionómeros de alta densidad disponibles en Lima-Perú se encuentran: Ionofil® Plus (VOCO), KetacTM Molar Easymix (3M ESPE), Fuji IX GP (GC corporation) y EQUIA Forte™®GC (Europe GC). Se presentan las propiedades y aplicación clínica de todos estos ionómeros. De acuerdo a la revisión de la literatura, de los cinco grupos estudiados: EQUIA Forte presentó una excelente adhesión al esmalte y la dentina. Fuji IX GP puede ser usado en restauraciones de Clase I y II, sin contactos oclusales y; EQUIA Forte puede utilizarse en pequeñas Clase II con /sin contactos oclusales, y con cuidado en grandes cavidades MOD siguiendo las recomendaciones del fabricante.

The objective of the review was to understand the properties and clinical application of the different high-density glass ionomers available in Lima, Perú. A review of the scientific literature about high-density glass ionomers, was conducted from January 2010 to December 2019. This review was performed in SciELO, Pubmed and Google Scholar databases. The descriptors used in the search were: glass ionomer cements, high density glass ionomers and physical properties, the combinations between them and their equivalent in English. Ultimately forty articles that met the inclusion criteria, were selected. The high-density ionomers available in Lima-Peru are Ionofil® Plus (VOCO), KetacTM Molar Easymix (3M ESPE), Fuji IX GP (GC corporation) and EQUIA Forte™® GC (Europe GC). The properties and clinical application of all these ionomers are presented. According to the literature review, of the five groups studied; EQUIA Forte presented excellent adhesion to enamel and dentin. Fuji IX GP can be placed in Class II restorations without occlusal contacts and EQUIA Forte can be used in small Class II with / without occlusal contacts, and cautiously in large MOD cavities following the manufacturer's recommendations.

Efecto Antimicrobiano de Tres Cementos Selladores Endodónticos frente a Streptococcus mutans, Enterococcus faecalis y Candida albicans

RESUMEN: El objetivo del estudio fue evaluar el efecto antimicrobiano de tres cementos selladores endodónticos frente a Streptococcus mutans, Enterococcus faecalis y Candida albicans. Se usó el método de difusión en agar, realizando pozos de 5 mm de diámetro por 4 mm de profundidad, en donde se colocaron los diferentes cementos que fueron preparados según las indicaciones del fabricante. Para S. mutans y E. faecalis se empleó agar cerebro-corazón, mientras que para C. albicans se empleó agar tripticasa soya como medios de cultivo. Las placas fueron incubadas por 48 horas a 37 ºC. Los halos de inhibición de crecimiento microbiano se midieron con un compás Vernier. Los resultados mostraron diferencias significativas entre todos los grupos p 0,05), siendo bastante inferior para E. faecalis (6,642 ? 0,659 mm) y C. albicans (8,781 ? 0,735 mm). El cemento a base de hidróxido de calcio (Sealer 26) fue más efectivo frente a S. mutans (13,010 ? 2,006 mm) que ante E. faecalis (6,165 ? 0,978 mm) y C. albicans (5,640 ? 0,280 mm). Como conclusión, el cemento a base de óxido de zinc y eugenol (Endofill) mostró el mejor efecto antimicrobiano contra las tres cepas, seguido de los cementos a base de resina (Vioseal) y finalmente hidróxido de calcio (Sealer 26).

ABSTRACT: The objective of the study was to evaluate the antimicrobial effect of three endodontic sealant cements for Streptococcus mutans, Enterococcus faecalis and Candida albicans. The agar diffusion method was used, making wells 5mm in diameter by 4mm deep, where the different cements that were prepared according to the manufacturer's instructions were placed. For S. mutans and E. faecalis, brain-heart agar was used, while for C. albicans trypticase soy agar was used as culture media. The plates were incubated for 48 hours at 37 ºC. The microbial growth inhibition halos were measured with a Vernier compass. The results showed significant differences between all groups p0.05), being considerably lower for E. faecalis (6.642 ? 0.659 mm) and C. albicans (8.781 ? 0.735 mm). Calcium hydroxide-based cement (Sealer 26) was more effective against S. mutans (13.010 ? 2.006 mm) than against E. faecalis (6.165 ? 0.978 mm) and C. albicans (5.640 ? 0.280 mm). In conclusion, cement based on zinc oxide and eugenol (Endofill) showed the best antimicrobial effect against the three strains, followed by resin-based cements (Vioseal) and finally calcium hydroxide (Sealer 26).

Cimento biocerâmico no tratamento conservador de perfuração radicular em molar inferior / Bioceramic sealer in conservative treatment of mandibular molar root perforation

Introdução: A perfuração radicular é um acidente técnico-operatório que resulta em comunicação da cavidade pulpar com os tecidos periodontais. Esse tipo de acidente pode apresentar prognóstico desfavorável, por afetar significativamente o soalho da câmara coronária ou os terços cervical, médio e apical do canal radicular. Entre os fatores que interferem no prognóstico das perfurações radiculares, destacam-se: localização, extensão, presença ou ausência de bolsa periodontal; tempo decorrido entre a perfuração e o tratamento; e tipo de material obturador. Nesse contexto, os cimentos obturadores de canais denominados biocerâmicos surgiram como uma proposta inovadora para tratamento de perfurações antes consideradas de prognóstico desfavorável. Objetivo: O presente trabalho teve por objetivo relatar o tratamento de uma perfuração radicular em molar inferior com o cimento biocerâmico EndoSequence BC Sealer, com três anos de acompanhamento. Resultados: As imagens radiográficas e os dados clínicos do paciente evidenciaram o sucesso no tratamento da perfuração, com reparo da lesão perirradicular. Conclusão: O cimento endodôntico biocerâmico EndoSequence BC Sealer associado com a retomada do trajeto original do conduto e sua instrumentação favoreceram o reparo dos tecidos perirradiculares, sugerindo propriedades biológicas promissoras de compatibilidade e bioativida (AU).

Introduction: Root perforation is a technical-surgical accident that results in communication of the pulp cavity with periodontal tissues. This type of accident may have an unfavorable prognosis because it significantly affects the floor of the coronary chamber or the cervical, middle and apical thirds of the root canal. Factors that interfere with the prognosis of root perforations include location, extension, presence or absence of periodontal pocket, time elapsed between perforation and treatment, and type of obturator material. In this context, bioceramic canal sealers have emerged as an innovative proposal for treatment of perforations previously considered to have an unfavorable prognosis. Objective: The aim of this study was to report the treatment of a lower molar root perforation with the EndoSequence BC Sealer bioceramic sealer after a 3-year follow up. Results: Radiographic images and patient clinical data showed success in the treatment of perforation with repair of the periradicular lesion. Conclusion: Endo-Sequence BC Sealer bioceramic endodontic sealer associated with the resumption of the original conduit path and its instrumentation favored the repair of periradicular tissues, suggesting promising biological properties of compatibility and bioactivity (AU).

Cytotoxicity and cytokine production by calcium silicate-based materials on periodontal ligament stem cells

Abstract This study investigated the effect of three commercial calcium silicate-based materials (CSBM) on cytotoxicity and pro-and anti-inflammatory cytokines production in cultured human periodontal ligament stem cells (hPDLSCs). Culture of hPDLSCs was established and characterized. Extracts of Bio-C Sealer (Angelus, Londrina, PR, Brazil), MTA Fillapex (Angelus, Londrina, PR, Brazil) and PBS Cimmo HP (Cimmo Soluções em Saúde, Pouso Alegre, MG, Brazil) were prepared by placing cement specimens (5 x 3 mm) in culture medium. Then, the extracts were serially two-fold diluted (1, 1:2, 1:4, 1:8, 1:16) and inserted into the cell-seeded wells for 24, 48 and 72 h for MTT assays. TNF-α and IL-10 cytokines were quantified by ELISA at 24h-cell supernatants. Data were analyzed by ANOVA and Tukey's test (α = 0.05). All CSBM exhibited some cytotoxicity that varied according to extract concentration and time of evaluation. MTA Fillapex presented the highest cytotoxic effects with significant reduction of metabolic activity/cell viability when compared to Bio-C Sealer and Cimmo HP®. TNF-α was significantly upregulated by the three tested cements (p < 0.05) while only MTA Fillapex significantly upregulated IL-10 in comparison to control. Taken collectively, the results showed that PBS Cimmo HP®, Bio-C Sealer and MTA Fillapex present mild and transient cytotoxicity and slightly induced TNF-α production. MTA Fillapex upregulated IL-10 release by hPDLSCs.

Resumo Este estudo investigou o efeito de três materiais comerciais à base de silicato de cálcio (CSBM) na citotoxicidade e na produção de citocinas pró e antiinflamatórias em células-tronco do ligamento periodontal humano (hPDLSCs). Cultura de hPDLSCs foi estabelecida e caracterizada. Extratos de Bio-C Sealer (Angelus, Londrina, PR, Brasil), MTA Fillapex (Angelus, Londrina, PR, Brasil) e PBS Cimmo HP® (Cimmo Soluções em Saúde, Pouso Alegre, MG, Brasil) foram preparados com a colocação de espécimes dos cimentos (5 x 3 mm) em meio de cultura. Em seguida, os extratos foram diluídos (1, 1: 2, 1: 4, 1: 8, 1:16) e inseridos nos poços semeados de células para ensaio de citotoxicidade por meio de MTT por 24, 48 e 72 h. As citocinas TNF-α e IL-10 foram quantificadas por ELISA em sobrenadantes de células de 24 h. Os dados foram analisados por ANOVA e teste de Tukey (α = 0,05). Todos os CSBM exibiram alguma citotoxicidade que variou de acordo com a concentração do extrato e o tempo de avaliação. O MTA Fillapex apresentou os maiores efeitos citotóxicos com redução significativa da atividade metabólica / viabilidade celular quando comparado ao Bio-C Sealer e Cimmo HP®. O TNF-α foi regulado positivamente pelos três cimentos testados (p <0,05), enquanto apenas o MTA Fillapex regulou positivamente a liberação de IL-10 em comparação com o controle. Tomados em conjunto, os resultados mostraram que PBS Cimmo HP®, Bio-C Sealer e MTA Fillapex apresentam citotoxicidade leve e transitória e induziram a produção de TNF-α. O MTA Fillapex regulou positivamente a liberação de IL-10 por hPDLSCs.

Avaliação da espessura de película de cimentos odontológicos para fixação de próteses fixas / Film thickness evaluation of dental cement for fixing prostheses fixed

A escolha errada do sistema cimentante pode levar ao fracasso clínico na cimentação de coroas e próteses parciais fixas. Este trabalho teve como objetivo estudar "in vitro" a espessura de película de seis cimentos odontológicos para fixação de peças protéticas, de três grupos distintos, sendo eles: dois cimentos de fosfato de zinco, dois cimentos de ionômero de vidro convencional e dois cimentos resinosos. Foi realizado a manipulação dos cimentos de acordo com as instruções dos fabricantes e após, interposto 1g de material entre duas placas de vidro polidas e sobre as mesmas um peso de 3 Kg, durante 10 minutos. Estas placas foram medidas com um paquímetro digital antes e após a presa dos materiais. Foi realizada a análise estatística com o teste T Student e com o Teste de Variância ANOVA e foi observado uma menor espessura de película de um cimento de ionômero de vidro perante os outros cimentos testados, com diferenças estatísticas ao nível de 5%. Os autores concluíram que o cimento de ionômero de vidro obteve a menor espessura de película, sendo apropriado para cimentação de coroas e pontes fixas... (AU)

The incorrect choice of the cementing system may lead to clinical failure in the cementation of fixed partial crowns and prostheses. The aim of this study was to study the film thickness of six dental cements for the fixation of prosthetic pieces from three different groups of cement: two zinc phosphate cements, two conventional glass ionomer cement and two resin cements. Handling of the cements was carried out according to the manufacturers' instructions and after 1g of material was placed between two polished glass plates and a weight of 3 kg was placed thereon for 10 minutes. These plates were measured with a digital caliper before and after the prey of the materials. Statistical analysis was performed with the Student T test and the ANOVA Variance Test, and a lower film thickness of a glass ionomer cement was observed compared to the other cements tested, with statistical differences at the level of 5%. The authors concluded that glass ionomer cement had the lowest film thickness and was suitable for cementation of fixed crowns and bridges... (AU)

Propriedades físico-químicas dos cimentos AH Plus e Sealer Plus: tempo de endurecimento e escoamento / Physicochemical properties of AH Plus and Sealer Plus cements: hardening and flow time

Introdução: O tratamento endodôntico busca sanificar o sistema de canais radiculares para permitir adequada obturação tridimensional. Para tanto, necessita-se de materiais plásticos, como a guta-percha, associados a cimentos endodônticos com adequadas características físico-químicas. Métodos: Comparação das propriedades físico-químicas tempo de endurecimento e escoamento dos cimentos endodônticos AH Plus e Sealer Plus, de acordo com a especificação 57 da American National Standard Institute/American Dental Association para materiais obturadores. Resultados: O tempo de endurecimento do AH Plus foi de 1178 minutos e do Sealer Plus foi de 422 minutos. O escoamento do APlus foi de 3259 milímetros e do Sealer Plus, 3150 milímetros. Conclusões: O tempo de endurecimento do AH Plus foi maior quando comparado ao do cimento Sealer Plus, e não houve diferença estatística no escoamento entre os cimentos estudados (AU).

Introduction: Endodontic treatment seeks to sanitize the root canal system to allow adequate three-dimensional filling, for which plastic materials such as guttapercha are required, associated with endodontic cements with adequate physico-chemical characteristics. Methods: Comparison of the physico-chemical properties hardening and flow time of the AH Plus and Sealer Plus endodontic sealers according to the American Dental Association / American Dental Association Specification 57 for sealing materials. Results: The hardening time of the AH Plus was 1178 minutes and the Sealer Plus was 422 minutes. The AH Plus flow was 3259 millimeters and the Sealer Plus was 3150 millimeters. Conclusions: The AH Plus hardening time was higher when compared to the Sealer Plus cement and there was no statistical difference in the flow between the cements studied (AU).

Use of Self-Adhesive Resin Cements in Dentistry: a Literature Review / Uso de Cimentos Resinosos Autoadesivos em Odontologia: uma Revisão da Literatura

Self-adhesive resin cements (SARCs) are cementing agents and have the objective of simplifying adhesive cementation, with a simplified use protocol. The aim of this article was to review the literature on SARCs with a focus on the advantages of their use, highlighting their adhesion and biocompatibility mechanism. Thus, the Health Sciences Descriptors "Self-Adhesive Resin Cement", "Dental Cements", "Adhesion" and "Dental Prosthesis" were used, as well as their Portuguese counterparts in the online databases SciELO, PubMed and Bireme in the period of time between the years 2000 to 2020. According to the studies, SARCs have excellent physical and mechanical properties, which include low solubility in the oral environment, adhesion to the dental substrate and the prosthetic part, color mimicry, biocompatibility and fluoride release, in addition to being applied in a single step, optimizing the operator's working time. In addition, self-adhesive cements seem to offer a promising new approach in indirect restorative procedures, which may present a performance similar to conventional ones, however more studies are needed to support their long-term applicability. (AU)

Os cimentos resinosos autoadesivos (CRAAs) são agentes de cimentação e possuem o objetivo de simplificar a cimentação adesiva, com um protocolo simplificado de utilização. Assim, o objetivo deste trabalho foi revisar na literatura acerca dos CRAAs com enfoque nas vantagens de sua adequada utilização, evidenciando seu mecanismo de adesão e biocompatibilidade. Dessa forma, foram utilizados os descritores em Ciências da Saúde (DeCS) "Cimento Resinoso Autoadesivo", "Cimentos Dentários", "Adesão" e "Prótese Dentária", assim como seus correspondentes na língua inglesa nas bases de dados online SciELO, PubMed e Bireme no período de tempo entre os anos 2000 a 2020. De acordo com os estudos, os CRAAs apresentam excelentes propriedades físicas e mecânicas, que incluem baixa solubilidade no meio bucal, adesão ao substrato dental e a peça protética, mimetização de cores, biocompatibilidade e liberação de fluoretos, além de serem aplicados em uma única etapa clínica, otimizando o tempo de trabalho do operador. Além disso, os cimentos autoadesivos oferecem uma nova abordagem promissora em procedimentos restauradores indiretos, podendo apresentar um desempenho semelhante aos convencionais, porém são necessários mais estudos que sustentem sua aplicabilidade a longo prazo. (AU)

Accuracy of digital bitewing radiographs with and without applying horizontal tube shift in the diagnosis of residual excess cement around dental implants: an in vitro study / Precisión de las radiografías digitales bitewing con y sin aplicación de desplazamiento horizontal del tubo en el diagnóstico del exceso de cemento residual alrededor de los implantes dentales: un estudio in vitro

Purpose: This study was designed to evaluate the diagnostic value of digital Bitewing (BW) radiographs with and without horizontal tube shift in detecting Residual excess cement (REC) on the proximal and non-proximal surfaces of implant restorations. Material and Methods: Eight mandibular models were fabricated with two implants placed on each side in the premolar and first molar positions. Excess cement was applied to either proximal or non-proximal surfaces of the restorations intentionally during the process of crown cementation. BW radiographs with and without applying horizontal tube shift were acquired. Three maxillofacial radiologists were asked to determine the presence and location of REC in the radiographs. Sensitivity and specificity of the radiographic technique were assessed according to the restoration surface that contained REC. Results: Sensitivity of BW radiographs was 100% for the detection of REC on the proximal surfaces and 41-18, 80% on the non-proximal surfaces. Specificity of the technique was 85.71%-100% for the proximal surfaces and 75-94. 12% for the non-proximal areas. Specificity of the radiographic method was generally greater than its sensitivity for the non-proximal surfaces while in the proximal areas, the two variables had quite similar values. Conclusion: Digital BW radiography is generally more useful for detection of REC on the proximal surfaces. Higher specificity of this technique for the bucco-lingual surfaces suggests more reliability of the negative diagnoses in the non-proximal areas.

Objetivo: Evaluar el valor diagnóstico de las radiografías digitales bitewing (BW), con y sin desplazamiento horizontal del tubo, para detectar el exceso de cemento residual (ECR) en las superficies proximales y no proximales de las restauraciones con implantes. Material y Métodos: Se fabricaron ocho modelos mandibulares con dos implantes colocados a cada lado en las posiciones premolar y primer molar. El exceso de cemento se aplicó intencionalmente en las superficies proximales o no proximales de las restauraciones durante el proceso de cementación de la corona. Se adquirieron radiografías BW con y sin aplicación de desplazamiento horizontal del tubo. Se pidió a tres radiólogos maxilofaciales que determinaran la presencia y ubicación de ECR en las radiografías. La sensibilidad y la especificidad de la técnica radiográfica se evaluaron según la superficie de restauración que contenía ECR. Resultados: La sensibilidad de las radiografías de BW fue del 100% para la detección de ECR en las superficies proximales y del 41,18-80% en las superficies no proximales. La especificidad de la técnica fue 85-71, 100% para las superficies proximales y 75-94, 12% para las áreas no proximales. La especificidad del método radiográfico fue generalmente mayor que su sensibilidad para las superficies no proximales, mientras que en las áreas proximales, las dos variables tuvieron valores bastante similares. Conclusión: La radiografía digital BW es generalmente más útil para la detección de ECR en las superficies proximales. La mayor especificidad de esta técnica para las superficies buco-linguales sugiere una mayor confiabilidad de los diagnósticos negativos en las áreas no proximales.