Development of a Fluorescence-Based Caries Scoring System for an Intraoral Scanner: An in vitro Study.

OBJECTIVES: To develop an automated fluorescence-based caries scoring system for an intraoral scanner and totest the performance of the system compared to state-of-the-art methods. METHODS: Seventy-three permanent posterior teeth were scanned with a three-dimensional (3D) intraoral scanner prototype which emitted light at 415 nm. An overlay representing the fluorescence signal from the tissue was mapped onto 3D models of the teeth. Multiple examination sites (n = 139) on the occlusal surfaces were chosen, and their red and green fluorescence signal components were extracted. These components were used to calculate 4 mathematical functions upon which a caries scoring system for the scanner prototype could be based. Visual-tactile (International Caries Detection and Assessment System, ICDAS), radiographic (ICDAS), and histological assessments were conducted on the same examination sites. RESULTS: Most index tests showed significant correlation with histology. The strongest correlation was observed for the visual-tactile examination (rs = 0.80) followed by the scanner supported by the caries classification function that quantifies the overall fluorescence compared to sound surfaces (rs = 0.78). Additionally, this function resulted in the highest intra-examiner reliability (κ = 0.964), and the highest sum of sensitivity (SE) and specificity (SP) (sum SE-SP: 1.60-1.84) at the 2 histological levels where the comparison with visual-tactile assessment was possible (κ = 0.886, sum SE-SP = 1.57-1.81) and at the 3 out of 4 histological levels where the comparison with radiographic assessment was possible (κ = 0.911, sum SE-SP = 1.37-1.78); the only exception was for the lesions in the outer third of dentin, where the radiographic assessment showed the highest sum SE-SP (1.78). CONCLUSION: A fluorescence-based caries scoring system was developed for the intraoral scanner showing promising performance compared to state-of-the-art caries detection methods. The intraoral scanner accompanied by an automated caries scoring system may improve objective caries detection and increase the efficiency and effectiveness of oral examinations. Furthermore, this device has the potential to support reliable monitoring of early caries lesions.

Do in vitro solubility studies on endodontic sealers demonstrate a high level of evidence? A systematic review.

OBJECTIVE: To systematically review the quality of evidence of available in vitro solubility studies on endodontic sealers according to prespecified evidence criteria. MATERIAL AND METHODS: This systematic review was based on the PRISMA guidelines and the AMSTAR measurement tool. A systematic duplicate search of the literature on endodontic sealer solubility studies was conducted in PubMed and Embase databases (until 18 October 2017). Mapping terms to subject headings and free text terms were used and combined with hand searching before exclusion of duplicates. Studies specifically dealing with endodontic sealer solubility were selected. The evidence level was graded (low, medium or high) independently by two investigators following systematic data extraction in pilot forms, which was based on prespecified evidence criteria and the modified CONSORT checklist for in vitro studies on dental materials. RESULTS: The search retrieved 1053 articles, from which 88 were assessed in full. From the 63 articles retained in the final analysis, 11 were classified as having moderate and 52 as low quality of evidence (0 high). The studies graded as low had low sample size (n < 10) and/or insufficient details to allow replicability. Most of the studies did not conform to the modified CONSORT checklist and did not include parameters considered relevant in the prespecified criteria. CONCLUSIONS: Existing in vitro studies on the solubility of endodontic sealers do not demonstrate a high quality of evidence. Most of these studies do not present systematic reporting nor employ relevant parameters prespecified in our evidence criteria.

Adhesion and marginal adaptation of a claimed bioactive, restorative material.

Objectives: Adhesion and marginal adaptation of a claimed bioactive restorative material (ACTIVA BioACTIVE Restorative) to human teeth were compared with those of a resin-modified glass ionomer cement (Fuji II LC) and a control resin composite (Ceram X Mono). Material and Methods: Shear bond strength and marginal adaptation to enamel and dentine were assessed after no pretreatment of the hard tissues or after etching with phosphoric acid (ACTIVA BioACTIVE Restorative and Ceram X Mono) or polyacrylic acid (Fuji II LC). For ACTIVA BioACTIVE Restorative, the effect of applying a self-etch adhesive (Xeno Select, Dentsply Sirona) was also investigated. Data were analyzed using non-parametric tests (α = 0.05). Results: Bond strength and marginal adaptation in enamel and dentine were significantly different among the investigated materials (p<.05). Due to loss of restorations, it was not possible to measure bond strength of ACTIVA BioACTIVE Restorative if no pretreatment was performed or if dentine was etched; however, use of the self-etch adhesive resulted in similar bond strength as Ceram X Mono. Etching improved adhesion of Fuji II LC to enamel and dentine. Regarding marginal adaptation, ACTIVA BioACTIVE Restorative showed the highest wall-to-wall contraction to enamel in all pretreatment groups and the overall highest wall-to-wall contraction to dentine after etching. Due to loss of restorations, no marginal assessment was possible on cavities with margins in dentine when no pretreatment was used. The use of a self-etch adhesive with ACTIVA BioACTIVE Restorative resulted in similar adaptation to dentine compared to the other materials. Conclusion: The self-adhesive property of ACTIVA BioACTIVE Restorative is nonexistent.

Challenges in luting fibre posts: Adhesion to the post and to the dentine.

OBJECTIVE: To investigate the relationship between physicochemical interactions of resin luting cements with dentine and retention of fibre posts in root canals. METHODS: Retention of fibre posts (RelyX Fiber Post) was assessed by the pull-out method. The diffusion zone of the cements and their chemical interaction with dentine were estimated by micro-Raman spectroscopy. Resin luting cements employing etch-and-rinse (Rely X Ultimate and Variolink II), self-etch (Rely X Ultimate and Panavia F2.0), or self-adhesive (RelyX Unicem 2) modes were investigated. Data were analyzed by analysis of variance followed by Tukey HSD tests. RESULTS: The retention of the fibre posts decreased in the following order: RelyX Ultimate, etch-and-rinse mode>RelyX Unicem 2≥RelyX Ultimate, self-etch mode≥Panavia F2.0≥Variolink II (p<0.05). One of the etch-and-rinse mode cements presented the deepest diffusion zone, while the other, along with the self-adhesive cement, produced the shallowest zone. Cements used in the self-etch mode showed intermediary diffusion into dentine (p<0.05). All resin luting cements showed some degree of chemical interaction with dentine, the highest recorded for RelyX Ultimate used in the etch-and-rinse mode and the lowest for Panavia F2.0 (p<0.05). The retention of fibre posts in the root canal could be attributed neither to the mode of interaction of the luting cements with dentine nor to their ability to diffuse into dentine. SIGNIFICANCE: Chemical interaction between the resin luting cement and the dentine paired with adequate post pretreatment contribute positively to the retention of fibre posts.

Susceptibility to Coffee Staining during Enamel Remineralization Following the In-Office Bleaching Technique: An In Situ Assessment.

PURPOSE: To assess in situ the enamel mineralization level and susceptibility to coffee staining after in-office bleaching. MATERIALS AND METHODS: Thirty-six human dental fragments assembled into intraoral devices were bleached with 35% hydrogen peroxide and treated as follows: (group 1) no contact with coffee; (group 2) immersion in a coffee solution for 30 minutes daily for 7 days, starting 1 week after bleaching; and (group 3) immersion in a coffee solution for 30 minutes daily for 14 days, starting immediately after bleaching. Enamel mineralization and color were assessed before bleaching (T1), immediately after bleaching (T2), and after 7 (T3) and 14 days (T4). The CIE whiteness index (W*) and closeness to white (ΔW*) following bleaching and/or immersion in coffee were calculated. Data were analyzed with Friedman and Wilcoxon tests or Kruskal-Wallis and Mann-Whitney U-tests (α = 0.05). RESULTS: Significant differences in the mineralization levels were observed as a function of time. No significant differences in W* were observed between groups, nor was W* significantly different at T3 and T4. Similar ΔW* was observed between groups after 7 or 14 days. CONCLUSIONS: The mineral loss after in-office bleaching was progressively reversed by contact with saliva for 14 days. The whiteness index was not affected by contact with coffee during the remineralization period. CLINICAL SIGNIFICANCE: The results of this in situ study suggest that the mineral loss caused by in-office dental bleaching is minimal and is partly compensated by remineralization due to contact with saliva. Additionally, whiteness was not affected by daily exposition to coffee during the enamel remineralization, which indicates that avoiding the consumption of coffee immediately following in-office bleaching is unnecessary. (J Esthet Restor Dent 28:S23-S31, 2016).

Colour stability, staining and roughness of silorane after prolonged chemical challenges.

OBJECTIVES: To investigate the effect of prolonged chemical challenges on colour stability, staining susceptibility, and roughness of a silorane composite material when compared to methacrylate-based composites. METHODS: Initial colour and roughness were registered for specimens fabricated from methacrylate or silorane composites. Specimens were individually stored at 37°C in 0.02 N citric acid, 0.02 N phosphoric acid, 75% ethanol or distilled water for 7, 14, 21 and 180 days, when new measurements were performed. A staining test was performed after the chemical challenge by immersion in coffee during 3 weeks at 37°C. Colour changes were characterized using the CIEL a b colour system. Data were submitted to analysis of variance for repeated measures, two-way analysis of variance and Tukey's multiple comparison test (α=0.05). RESULTS: Colour changes on the methacrylate-based resins were considered acceptable (although significantly different) after immersion in water, citric acid, phosphoric acid or ethanol, but were unacceptable for the silorane composite immersed in ethanol for 180 days. The methacrylate-based resins stored in ethanol were significantly more stained by coffee than those stored in other media. The silorane composite demonstrated no staining, but increased roughness, when compared to the methacrylate-based resins. CONCLUSIONS: No effect of the immersion solution was noticed on roughness of the investigated materials. Ethanol influenced colour stability and staining susceptibility differently for the methacrylate-based and silorane composites. CLINICAL SIGNIFICANCE: The knowledge of how acids and solvents affect the properties of tooth-coloured restorative materials is one of the decision-making criteria for the selection of a restorative material.

Relação entre cárie dentária, edentulismo e autopercepção de saúde bucal em adolescentes, adultos e idosos de um município do nordeste brasileiro / Relationship between dental caries, edentulism and self-perception of oral health in adolescents, adults and elderly of a municipality in northeastern Brazil

O diagnóstico das condições e autopercepção da saúde bucal dos indivíduos é fundamental nas estratégias de planejamento e avaliação dos serviços de saúde. O objetivo deste estudo foi descrever a prevalência da cárie dentária, do edentulismo e a autopercepção em saúde bucal na população adolescente, adulta e idosa de um município de pequeno porte da região nordeste do Brasil. Adicionalmente, investigou-se a relação entre a autopercepção e as variáveis clínicas investigadas. Compuseram a amostra de estudo 139 indivíduos. Nos exames clínicos foi usado o índice CPO-D, segundo critérios da OMS e as informações sobre autopercepção foram obtidas por entrevistas. Na análise dos dados foram usados os testes Qui-quadrado, Mann Whitney e Exato de Fischer, com nível de significância de 5%. O índice CPO-D foi 6,57± 4,17 para adolescentes, 22,76±7,63 para adultos e 30,96±2,82 para idosos. Foi registrado predomínio da autopercepção negativa da saúde bucal entre adultos (58,6%) e positiva, entre idosos (57,7%). Autopercepções negativas da mastigação (p<0,001) e da fala (p=0,001) associaram-se ao aumento da idade. O índice CPO-D foi maior entre adolescentes com relato de dor (p=0,028). Nos adultos, a autopercepção negativa da saúde bucal (p=0,007), aparência de dentes/gengivas (p=0,003) e fala (p=0,046) associou-se ao maior número de dentes cariados presentes. Foi evidenciada a discrepância entre autopercepção positiva em saúde bucal e presença de edentulismo. Os resultados sugerem a necessidade do estabelecimento de políticas locais de saúde bucal, voltadas para a promoção da saúde, focadas na prevenção da cárie dentária e do edentulismo.

The diagnosis of conditions and self-perceived oral health status of individuals is fundamental in planning strategies and evaluation of health services. The aim of this study was to describe the prevalence of dental caries, edentulism and self-perception of oral health in adolescents, adults and elderly in a small city in northeastern Brazil. Additionally, we investigated the relationship between self-perception and the clinical variables studied. The study sample consisted of 139 subjects. In clinical examinations the DMFT index was used according to WHO criteria and information about self-perception was collected through interviews. The Chi-square, Mann Whitney and Fisher exact tests were used with 5% significance level . The DMFT index was 6.57 ± 4.17 for adolescents, 22.76 ± 7.63 for adults and 30.96 ± 2.82 for elderly. It was recorded predominance of negative self-perception of oral health among adults (58.6%) and positive self-perception among the elderly (57.7%). Negative self-perceptions of chewing (p <0.001) and speech (p = 0.001) were associated with increasing age. The DMFT index was higher among adolescents with a history of pain (p = 0.028). In adults, the negative self-perception of oral health (p = 0.007), appearance of teeth / gums (p = 0.003) and speech (p = 0.046) was associated with higher number of decayed teeth present. The discrepancy between positive self-perception of oral health and the presence of edentulism was highlighted. The results suggest the need to establish local policies for oral health aimed at promoting health and focused on preventing dental caries and edentulism.

Factors related to oral health-related quality of life of independent brazilian elderly.

The aim of this cross-sectional study was to assess the factors associated with the impact of oral health on the quality of life in a sample of 504 Brazilian independent elderly. Data collection included oral examinations and structured interviews. The simplified form of the Oral Health Impact Profile (OHIP-14) was used to measure OHRQoL. Information on sociodemographic characteristics, use of dental services, and subjective measures of health was collected. Poisson regression within a hierarchical model was used to data analyses. The following variables were associated with a negative impact on OHRQoL: female gender (PR = 1.40; CI 95%: 1.11-1.77); lower class (PR = 1.58; CI 95%: 1.13-2.20); up to 3 occluding pairs of posterior teeth (PR = 1.88; CI 95%: 1.13-3.14); at least one untreated caries (PR = 1.28; CI 95%: 1.06-1.54); curative reasons for the last dental appointment (PR = 1.52; CI 95%: 1.15-2.00); poor self-perception of oral health (PR = 2.49; CI 95%: 1.92-3.24); and poor perception of dental care provided (PR = 1.34; CI 95%: 1.12-1.59). The younger elderly also noticed this negative impact. These findings showed that the clinical, sociodemographic, and subjective factors evaluated exerted a negative impact on OHRQoL in elderly people. Health authorities must address all these factors when planning interventions on oral health for this population.

Accuracy of Single-Step versus 2-Step Double-Mix Impression Technique.

Objective. To investigate the accuracy of dies obtained from single-step and 2-step double-mix impressions. Material and Methods. Impressions (n = 10) of a stainless steel die simulating a complete crown preparation were performed using a polyether (Impregum Soft Heavy and Light body) and a vinyl polysiloxane (Perfectim Blue Velvet and Flexi-Velvet) in two consistencies, in one or two (without relief) steps. Accuracy of the stone dies was accessed at a measuring microscope, using a metallic crown with perfect fit to the reference crown preparation. Data were submitted to 2-way ANOVA and Tukey test (α = 0.05). Results. The single-step technique resulted in slightly larger dies, while the 2-step technique without relief produced significantly smaller dies, when compared to the original stainless steel die. Stone dies obtained from 2-step polyether impressions were significantly smaller when compared to dies obtained from 2-step vinyl polysiloxane impressions (Impregum 2-step: -290.94 ± 71.64 µm; Perfectim 2-step: -201.86 ± 28.58 µm). No significant differences were observed in dies obtained from either polyether or vinyl polysiloxane with the single-step technique (Impregum single-step: 63.52 ± 16.60 µm; Perfectim single-step: 79.40 ± 14.11 µm). Conclusion. Higher discrepancies were detected for the 2-step impression technique without relief for the investigated materials.

Influence of curing rate on softening in ethanol, degree of conversion, and wear of resin composite.

PURPOSE: To investigate the effect of curing rate on softening in ethanol, degree of conversion, and wear of resin composites. METHOD: With a given energy density and for each of two different light-curing units (QTH or LED), the curing rate was reduced by modulating the curing mode. Thus, the irradiation of resin composite specimens (Filtek Z250, Tetric Ceram, Esthet-X) was performed in a continuous curing mode and in a pulse-delay curing mode. Wallace hardness was used to determine the softening of resin composite after storage in ethanol. Degree of conversion was determined by infrared spectroscopy (FTIR). Wear was assessed by a three-body test. Data were submitted to Levene's test, one and three-way ANOVA, and Tukey HSD test (alpha = 0.05). RESULTS: Immersion in ethanol, curing mode, and material all had significant effects on Wallace hardness. After ethanol storage, resin composites exposed to the pulse-delay curing mode were softer than resin composites exposed to continuous cure (P< 0.0001). Tetric Ceram was the softest material followed by Esthet-X and Filtek Z250 (P< 0.001). Only the restorative material had a significant effect on degree of conversion (P< 0.001): Esthet-X had the lowest degree of conversion followed by Filtek Z250 and Tetric Ceram. Curing mode (P= 0.007) and material (P< 0.001) had significant effect on wear. Higher wear resulted from the pulse-delay curing mode when compared to continuous curing, and Filtek Z250 showed the lowest wear followed by Esthet-X and Tetric Ceram.

Stepwise excavation in a permanent molar: 17-year follow-up.

The current study presents a 17-year clinical report of stepwise excavation and indirect pulp capping in a lower right first molar, with great dentin destruction and a lack of dentin support of the cusps. At the first appointment, indirect pulp capping with calcium hydroxide and a temporary filling with zinc oxide cement were performed to minimize the risk of pulp exposure during excavation. After 45 days, the remaining carious tissue was removed and a restoration with glass-ionomer lining (Vitrebond) and resin composite (P-50) was performed. Satisfactory morphology and function of the restoration and pulp vitality were preserved for 17 years, thus indicating that stepwise excavation can be a good treatment alternative in selected cases.

Remodelación Cosmética de la Sonrisa / Cosmetic Contouring of Smile

La remodelación cosmética de los dientes naturales es una modalidad de tratamiento con beneficios estéticos que puede ser considerada económica y conservadora. No obstante, demanda del profesional no solo restaurar una sonrisa armoniosa, sino también, al mismo tiempo preocuparse con el aspecto funcional del tratamiento. Además, la remodelación cosmética pude ser relacionada a otros recursos operatorios como los restauradores adhesivos directos, proporcionando resultados aún más satisfactorios a los pacientes. De esta manera, este trabajo tiene por objetivo presentar un caso clínico, en el cual la remodelación cosmética asociada a diferentes recursos operatorios, puede ser empleada como una opción de tratamiento estético conservador.

Cosmetic contouring of natural teeth is a treatment with aesthetic benefits that can be considered economical as well as conservative. The dental professional has however not only to restore the smile harmony, but the functional aspects have to be considered at the same time in the treatment planning. Other treatments such as direct adhesive restorative treatments may additionally be used to provide better outcomes to the patients. The aim of the present work thus is to present a case of cosmetic contouring as a suitable aesthetic treatment option.

Abordagem interdisciplinar para o fechamento de diastemas associados à discrepância de Bolton / Interdisciplinary management of diastemata associated to Bolton discrepancy

Diastemas anteriores podem comprometer a harmonia do sorriso. Devido à multiplicidade de suas etiologias, a eleboração de um plano de tratamento individual é essencial para o sucesso do tratamento. Muitas alternativas têm sido propostas para a finalização de tratamentos ortodônticos na presença de diastemas múltiplos remanescentes em função da discrepância dentária de Bolton. Pretende-se, com este trabalho, enfatizar o tratamento interdisciplinar, ressaltando a importância da contribuição da Dentística na finalização de casos ortodônticos. O uso da resina composta na técnica direta é uma alternativa conservadora, previsível e reversível.

Tecnica caseira de clareação dentária em Odontologia Restauradora Cosmética / The use of home-bleaching technique in Cosmetic Restorative Dentistry

Historicamente, a clareação dentária tem sido uma alternativa conservadora de tratamento para dentes com manchamento intrínseco. Desde a descrição da técnica de clareação caseira por Haywood e Heymann, em 1989, diferentes métodos têm sido utilizados para se obter a clareação dentária. Em função dos bons resultados estéticos, tem sido amplamente utilizada pelos cirurgiões-dentistas. A clareação dentária possui a vantagem de permitir a associação com as demais técnicas restauradoras estéticas e/ou cosméticas. O tratamento clareador vem sendo utilizado como uma das técnicas cosméticas mais comumente requisitadas pelos pacientes. Dessa forma, o objetivo deste trabalho é apresentar e discutir a técnica de clareação caseira, com a apresentação de casos clínicos.

Fechamento de diastemas múltiplos anteriores com resina composta / Closing anterior diastemata with composite resin

Muitas alternativas têm sido propostas para a finalização de tratamentos ortodônticos na presença de diastemas múltiplos remanescentes em função da discrepância dentária de Bolton. Os autores apresentam um caso clínico de abordagem interdisciplinar, no qual, após a terapia ortodôntica, realizou-se um guia de silicone a partir do enceramento diagnóstico do modelo de gesso, que serviu como referência na orientação dos incrementos de resina composta realizada pela técnica direta. Pretende-se, com este trabalho, ressaltar a importância da contribuição da dentística restauradora na finalização de casos ortodônticos. O uso da resina composta na técnica direta mostrou ser uma alternativa conservadora, previsível e reversível.

Many alternatives have been proposed for the completion of orthodontic treatment in the presence of remaning diastemata according to the Bolton analysis. The aim of this work is to highlight the contribution of operative dentistry in the finishing of orthodontic cases and to present a interdisciplinary approach. After orthodontic treatment, a silicon index of the palatal and incisal surfaces was obtained on the wax-up cast which served as reference for the direct resin composite restorations. The use of the direct resin composite technique has shown to be a predictable and reversible conservative alternative.

Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1) rinsing with water and drying; (G2) application of an adhesive system; (G3) rinsing and drying, abrasion with finishing disks, etching and application of adhesive system; (G4) rinsing and drying, etching, application of silane and adhesive system. Resin cylinders were placed over the treated surfaces. The specimens were stored in water or ethanol. Shear bond strength tests were performed and the mode of failure was evaluated. Data were submitted to two-way ANOVA and Dunnett T3 test. Contamination of resin-resin interfaces with saliva significantly reduced shear strength, especially after prolonged storage (p<0.05). Similar values to the original bond strength were obtained after abrasion and application of adhesive (G3) or etching and application of silane and adhesive (G4). If contamination occurs, a surface treatment is required to guarantee an adequate interaction between the resin increments.

Tooth structure and fracture strength of cavities.

This study evaluated, in vitro, the loss of tooth substance after cavity preparation for direct and indirect restorations and its relationship with fracture strength of the prepared teeth. Sixty sound human maxillary first premolars were assigned to 6 groups (n=10). MOD direct composite cavities (Groups I, II and III) and indirect inlay cavities (Groups IV, V and VI) were prepared maintaining standardized dimensions: 2-mm deep pulpal floors, 1.5-mm wide gingival walls and 2-mm high axial walls. Buccolingual width of the occlusal box was established at 1/4 (Groups I and IV), 1/3 (Groups II and V) or 1/2 (Groups III and VI) of the intercuspal distance. Teeth were weighed (digital balance accurate to 0.001 g) before and after preparation to record tooth substance mass lost during cavity preparation. The prepared teeth were submitted to occlusal loading to determine their fracture strength using a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey test (alpha= 0.05). 1/4-inlay cavities had higher percent mean mass loss (9.71%) than composite resin cavities with the same width (7.07%). 1/3-inlay preparations also produced higher percent mean mass loss (13.91%) than composite resin preparations with the same width (10.02%). 1/2-inlay cavities had 21.34% of mass loss versus 16.19% for the 1/2-composite resin cavities. Fracture strength means (in kgf) were: GI = 187.65; GII = 143.62; GIII = 74.10; GIV = 164.22; GV = 101.92; GVI = 50.35. Statistically significant difference (p<0.05) were observed between Groups I and IV, II and V, III and VI. Higher tooth structure loss and lower fracture strength were recorded after preparation of inlay cavities, regardless of the width of the occlusal box, compared to the direct composite resin cavities.

Effect of storage period on the accuracy of elastomeric impressions

AIMS: To investigate the effect of the storage period on the accuracy of recently developed elastomeric materials. METHODS: Simultaneous impressions of a steel die were taken using a polyether (I: Impregum Soft Heavy and Light body, 3M ESPE) and vinyl polysiloxane (P: Perfectim Blue Velvet and Flexi-Velvet, J.Morita). The trays were loaded with the heavy-bodied impression materials while the light-bodied impression materials were simultaneously spread on the steel die. The impressions were poured after 2 hours, 24 hours, and 7 days. Impressions were stored at approximately 55 percent relative humidity and room temperature. Ten replicas were produced for each experimental condition (n=60). Accuracy of the stone dies was assessed with a depth-measuring microscope. The difference in height between the surface of the stone die and a standard metallic ring was recorded in micrometers at four demarcated points, by two independent examiners. Data were submitted to two-way ANOVA and Tukey test (a = 0.05). RESULTS: Significant differences were found among the groups. Smaller discrepancies were observed when pouring was performed up to 24 hours (I-2h= 65.0 ± 15.68 µm; I-24h= 81.6 ± 11.13 µm) for the polyether, and up to 7 days for the vinyl polysiloxane (P-2h= 79.1 ± 13.82 µm; P-24h= 96.8 ± 6.02 µm; P-7d= 81.4 ± 4.3 µm). Significant dimensional discrepancies, however, were observed when polyether was stored for 7 days (I-7d= 295.3 ± 17.4 µm). CONCLUSION: Storage may significantly affect the dimensional accuracy of impressions and, thus, a maximum period and storage condition should be specified for the recently developed materials.

Multidisciplinary management of anterior diastemata: clinical procedures.

Anterior diastemata may compromise the harmony of a patient's smile. Consideration of etiologic factors, previous gingival conditioning, and individual treatment planning are essential in the proper management of anterior diastemata. An integrated orthodontic-restorative approach may enhance the aesthetic results when orthodontic therapy itself is not feasible. This article presents integrated orthodonticrestorative solutions of anterior diastemata, associated with the conditioning of the gingival tissue with composite resin, and discusses the most relevant aspects related to their etiology and treatment planning.