Searched for: person:rh1694
Full-mouth adhesive rehabilitation of a severe case of erosion treated with v-shaped veneers
Dallari, Giacomo; Scalzo, Ivan; Rosati, Riccardo Maria; Sampaio, Camila Sobral; Hirata, Ronaldo
OBJECTIVE:To demonstrate a minimally invasive approach of a full-mouth rehabilitation of a severe case of erosion treated with v-shaped veneers, tabletops, overlays, veneerlays, laminate veneers, and a full contour veneer. CLINICAL CONSIDERATIONS/UNASSIGNED:The present case report successfully rehabilitated a full-mouth case of severely eroded teeth with minimal healthy structure removal, maintaining viability of all teeth that were vital before the treatment started, and promoting long-lasting esthetic and functional results after 3 years of use. CONCLUSIONS:A deep knowledge of etiology, etiopathogenesis, and classifications of dental erosion will guide the clinician in the right direction for solving this issue correctly, according to modern prosthetic and conservative principles. CLINICAL SIGNIFICANCE/CONCLUSIONS:Dental erosion represents today a relatively widespread phenomenon among the global population and a significant challenge in each of its clinical stages for the clinicians who must treat it. In advanced stages, a careful evaluation phase of the case, a great patient motivation and a wise use of materials and clinical protocols are the success key of the case. Moreover, an advanced knowledge of adhesive dentistry is strictly required to successfully manage a severe erosion case with a modern and minimally invasive approach.
PMID: 33460516
ISSN: 1708-8240
CID: 4760252
Microcomputed tomography evaluation of cement film thickness of veneers and crowns made with conventional and 3D printed provisional materials
Sampaio, Camila S; Niemann, Katherin D; Schweitzer, Daniel D; Hirata, Ronaldo; Atria, Pablo J
OBJECTIVE:To evaluate, through microcomputed tomography (μCT), the cement film thickness of veneers and crowns made with different provisional materials. MATERIAL AND METHODS/METHODS:A veneer and a crown preparation were performed on a central incisor and a second molar of a dental model, respectively, scanned with an intraoral scanner, and the .stl files were exported to an LCD-based SLA three-dimensional (3D)-Printer. Twenty-four preparations were 3D-printed for each veneer and crown and divided into four groups (n = 6/group): (a) Acrylic resin (AcrÃlico Marche); (b) Bisacrylic resin (Protemp 4); (c) PMMA computer-aided design and computer-aided manufacturing (CAD-CAM) (Vipiblock); and (d) 3D-printed resin for provisional restorations (Raydent C&B for temporary crown and bridge). Veneers and crowns restorations were performed and cemented with a flowable composite. Each specimen was scanned with a μCT apparatus, files were imported for data analysis, and cement film thickness was quantitatively measured. Data were analyzed by 2-way ANOVA and Tukey post-hoc tests (α = .05). RESULTS:Crowns presented a thicker cementation film than veneers (P < .05).The bisacrylic resin showed the smallest veneer film thickness, similar to the acrylic resin (P = .151), which was not significantly different than the PMMA CAD/CAM material (P = .153). The 3D printed provisional material showed the thicker film, different than all other materials (P < .05). The bisacrylic resin showed a cement film thickness with a high number of voids in its surface. For crowns cementation, the 3D printed provisional material showed the thicker cementation film, different than all other materials (P < .05). CONCLUSIONS:Different provisional materials present different film thicknesses. The 3D printed provisional material showed the highest veneer and crown film thicknesses. Veneers film thicknesses were smaller than crowns for all provisional materials. CLINICAL SIGNIFICANCE/CONCLUSIONS:The 3D printed provisional material studied can be satisfactorily used, presenting appropriate adaptation with the tooth preparation, however, it shows the highest cement film thickness for both veneers and crowns cementations when compared with other provisional materials. A better internal fit, or smaller cement film thickness is obtained by CAD/CAM materials, acrylic and bisacrylic resins. Veneer cementation showed a smaller cement film thickness compared with crown cementation for all provisional materials.
PMID: 32937028
ISSN: 1708-8240
CID: 4593142
The injectable resin composite restorative technique: A case report
Ypei Gia, Nathalia Ramos; Sampaio, Camila Sobral; Higashi, Cristian; Sakamoto, Antonio; Hirata, Ronaldo
OBJECTIVE:To describe the use of the injectable resin composite restorative technique with a flowable resin material, in a clinical case with esthetic problems associated with irregular tooth anatomies, allied with a finishing, and polishing protocol due to staining after 1 year of use. CLINICAL CONSIDERATIONS/UNASSIGNED:The presented case report helped to achieve an immediate highly esthetic restoration with appropriate width proportions based on a previous wax-up. After 1 year of use, restorations presented staining; therefore, finishing and polishing procedures were required to re-achieve acceptable esthetic results and thus increase restoration's survival. CONCLUSIONS:The use of the presented technique allowed to obtain a simple and predictable workflow; however, care must be taken on the follow up of the restorations due to intrinsic characteristics of the flowable resin material. CLINICAL SIGNIFICANCE/CONCLUSIONS:The use of the presented injectable technique helped on obtaining a precise anatomy replicating a diagnostic wax-up, thus improving marginal precision and achieving a highly esthetic and functional immediate outcome, with an easy workflow when appropriately planned and executed. However, it also presented low color stability after 1 year of use only, thus, requiring attention from clinicians in regard to its maintenance over time.
PMID: 32918395
ISSN: 1708-8240
CID: 4592262
Analysis of the color matching of universal resin composites in anterior restorations
de Abreu, João Luiz Bittencourt; Sampaio, Camila Sobral; Benalcázar Jalkh, Ernesto Byron; Hirata, Ronaldo
OBJECTIVE:To evaluate color matching of universal composite restorations performed in anterior teeth using two evaluation methods. MATERIALS AND METHODS/METHODS:Sixty class III preparations were made on denture central incisors with different shades (A1-A3) and restored with multishade (Tetric Evoceram, Filtek Universal, and TPH Spectra Universal) and single-shade (Omnichroma) universal composites (n = 5). For photographic analysis, a digital photograph of each specimen was taken under standardized set-up. Color measurements were taken in the center of the restoration, and in the tooth surface 1.0 mm adjacent from the tooth/restoration margin. CIELab coordinates were recorded and color difference analysis (ΔE) was made using the CIEDE-2000 formula. For visual analysis, calibrated observers performed visual scoring of color matching and differences were graded as 0:excellent match; 1:very good match; 2:not so good match; 3:obvious mismatch; 4:huge mismatch. All data were statistically analyzed using a linear mixed model analysis with a confidence interval of 95%. RESULTS:For photographic analysis, Omnichroma showed the highest ΔE compared to the other composites for all shades (P < .05), without difference among experimental groups regarding tooth shade. For visual analysis, Omnichroma showed the highest scores (P < .05) for all teeth shades, without differences between the other groups. Furthermore, there were no differences between visual scores for different shades of a same resin composite group. CONCLUSIONS:Multishade universal composites presented higher color matching than the single shade universal composite. There were no differences of color matching for different tooth shades for all composites. CLINICAL SIGNIFICANCE/CONCLUSIONS:Universal composites with increased color matching may be helpful to simplify anterior restorations, minimizing clinical errors.
PMID: 32989879
ISSN: 1708-8240
CID: 4616672
Effect of universal adhesive application on bond strength of four-year aged composite repair
Willers, Amanda Endres; Ayres, Ana Paula Almeida; Hirata, Ronaldo; Giannini, Marcelo
ISI:000706288800001
ISSN: 0169-4243
CID: 5071662
Heating and preheating of dental restorative materials-a systematic review
Lopes, Larissa Coelho Pires; Terada, Raquel Sano Suga; Tsuzuki, Fernanada Midori; Giannini, Marcelo; Hirata, Ronaldo
OBJECTIVES/OBJECTIVE:To perform a review on the influence of preheating and/or heating of resinous and ionomeric materials on their physical and mechanical properties and to discuss the benefits and methods of preheating/heating that have been used. MATERIAL AND METHODS/METHODS:A search was performed in the Pubmed, Scopus, Scielo, and gray literature databases. In vitro studies published from 1980 until now were searched using the descriptors "composite resins OR glass ionomer cements OR resin cements OR adhesives AND heating OR preheating." Data extraction and quality of work evaluation were performed by two independent evaluators. RESULTS:At the end of reading the search titles and abstracts, 74 articles were selected. Preheating of composite resins reduces viscosity, facilitates adaptation to cavity preparation walls, increases the degree of conversion, and decreases the polymerization shrinkage. Preheating of resin cements improves strength, adhesion, and degree of conversion. Dental adhesives showed good results such as higher bond strength to dentin. However, unlike resinous materials, ionomeric materials have an increase in viscosity upon heating. CONCLUSIONS:Preheating improves the mechanical and physical properties. However, there is a lack of clinical studies to confirm the advantages of preheating technique. CLINICAL RELEVANCE/CONCLUSIONS:Preheating of dental restorative materials is a simple, safe, and successful technique. In order to achieve good results, agility and training are necessary so the material would not lose heat until the restorative procedure. Also, care is necessary to avoid bubbles and formation of gaps, which compromises the best restoration performance.
PMID: 33083851
ISSN: 1436-3771
CID: 4642822
Effect of Shortened Light-Curing Modes on Bulk-Fill Resin Composites
Sampaio, C S; Pizarro, P G; Atria, P J; Hirata, R; Giannini, M; Mahn, E
CLINICAL RELEVANCE/UNASSIGNED:Shortened light curing does not affect volumetric polymerization shrinkage or cohesive tensile strength but negatively affects the shear bond strength of some bulk-fill resin composites. When performing shortened light curing, clinicians should be aware of the light output of their light-curing units. SUMMARY/CONCLUSIONS:Purpose: To evaluate volumetric polymerization shrinkage (VPS), shear bond strength (SBS) to dentin, and cohesive tensile strength (CTS) of bulk-fill resin composites (BFRCs) light activated by different modes.Methods and Materials: Six groups were evaluated: Tetric EvoCeram bulk fill + high mode (10 seconds; TEC H10), Tetric EvoFlow bulk fill + high mode (TEF H10), experimental bulk fill + high mode (TEE H10), Tetric EvoCeram bulk fill + turbo mode (five seconds; TEC T5), Tetric EvoFlow bulk fill + turbo mode (TEF T5), and experimental bulk fill + turbo mode (TEE T5). Bluephase Style 20i and Adhese Universal Vivapen were used for all groups. All BFRC samples were built up on human molar bur-prepared occlusal cavities. VPS% and location were evaluated through micro-computed tomography. SBS and CTS tests were performed 24 hours after storage or after 5000 thermal cycles; fracture mode was analyzed for SBS.Results: Both TEC H10 and TEE H10 presented lower VPS% than TEF H10. However, no significant differences were observed with the turbo-curing mode. No differences were observed for the same BFRC within curing modes. Occlusal shrinkage was mostly observed. Regarding SBS, thermal cycling (TC) affected all groups. Without TC, all groups showed higher SBS values for high mode than turbo mode, while with TC, only TEC showed decreased SBS from high mode to turbo modes; modes of fracture were predominantly adhesive. For CTS, TC affected all groups except TEE H10. In general, no differences were observed between groups when comparing the curing modes.Conclusions: Increased light output with a shortened curing time did not jeopardize the VPS and SBS properties of the BFRCs, although a decreased SBS was observed in some groups. TEE generally showed similar or improved values for the tested properties in a shortened light-curing time. The VPS was mostly affected by the materials tested, whereas the SBS was affected by the materials, curing modes, and TC. The CTS was not affected by the curing modes.
PMID: 32101499
ISSN: 1559-2863
CID: 4735402
Monolithic CAD/CAM laminate veneers: Reliability and failure modes
Romanini-Junior, José Carlos; Hirata, Ronaldo; Bonfante, Estevam A; Bordin, Dimorvan; Kumagai, Rose Yakushijin; Fardin, Vinicius P; Coelho, Paulo G; Reis, André F
OBJECTIVES/OBJECTIVE:to evaluate the probability of survival and failure modes of lithium-disilicate, feldspathic-ceramic, and resin-nanoceramic anterior veneers cemented on dentin analog substrates after sliding-contact step-stress accelerated life testing (SSALT). METHODS:A virtual incisor tooth preparation was produced with a reduction of 1.5mm at the incisal edge and of 0.7mm buccally. A .STL file of the preparation was generated and CAD/CAM based G10 dentin-analog material was used for testing. Laminate veneers were milled in three different materials: lithium-disilicate (LDS, E.max CAD), resin-nanoceramic (RN, Lava Ultimate), and feldspathic-ceramic (FELDS, Vita Blocks). SSALT was employed where a spherical indenter contacted the veneer, slided along its interface with G10 to lift off and start a new cycle at 2Hz in water. Qualitative fractography was performed. The probability of survival (90% confidence-bounds) was calculated for several load/cycle missions. RESULTS:The probability of survival for a mission of 50,000 cycles decreased from 50 up to 150N equally for all groups and were not different between them. At 200N, the probability of survival was significantly lower for FELDS (10%) compared to RN veneers (41%), whereas LDS presented intermediate values (22%). The characteristic strength of RN (247N) was significantly higher than LDS (149N), and FELDS (151N). In FELDS and LDS, hackles, wake hackles and twist hackles indicated the direction of crack propagation. In RN, hackles were observed. CONCLUSIONS:Differences in probability of survival were observed only at 180 and 200N between groups. Failure modes were similar with veneer fracture down to the tooth-analog substrate.
PMID: 32359850
ISSN: 1879-0097
CID: 4422342
Copy milling to duplicate the emergence profile for implant-supported restorations
Conejo, Julian; Atria, Pablo J; Hirata, Ronaldo; Blatz, Markus B
This technique article describes the duplication of a definitive implant-supported computer-aided design and computer-aided manufacture (CAD-CAM) crown with soft-tissue modification on a misplaced implant. Gingival contours were ideally shaped in the stone die, and a custom healing abutment was designed. After scanning the modified surface, images were correlated with the initial intraoral digital scan, and the definitive restoration was designed, milled, and delivered with an ideal soft-tissue emergence profile.
PMID: 31582167
ISSN: 1097-6841
CID: 4116952
In vitro evaluation of composite resin fluorescence after natural aging
Garrido, Talissa-Mayer; Hoshino, Lidiane-Vizioli-de Castro; Hirata, Ronaldo; Sato, Francielle; Neto, Antonio-Medina; Guidini, Victor-Hugo-Fazoli; Terada, Raquel-Sano-Suga
Background/UNASSIGNED:Some composite resins contain luminophorous agents in order to reproduce tooth fluorescence. The objective of this study was to compare the fluorescence spectra emitted by composite resins with those of human enamel and dentin, and their emission behaviour after a 90-day natural aging period. Material and Methods/UNASSIGNED:<0.05). Results/UNASSIGNED:Fluorescence spectra baseline values of composites demonstrated no differences in intensity among the excitation peaks tested, with maximum emission found at the peak of 450 nm. Enamel and dentin spectra varied with different excitations, and the greater the excitation, the longer the wavelength in comparison to composite resins. After 90 days, XT presented an increase in fluorescence intensity, while OP and ED showed a reduction when compared with baseline values. Conclusions/UNASSIGNED:Composite resins, dental materials, fluorescence, fluorescence spectrometry.
PMCID:7263776
PMID: 32509228
ISSN: 1989-5488
CID: 4477752