Impact of restoration thickness and tooth shade background on the translucency of zirconia laminate veneers: An in vitro comparative study.

Purpose: Our in vitro comparative study aimed to investigate the impact of thickness and tooth shade background on the translucency of highly translucent zirconia veneers. Materials and Methods: A total of 75 5Y-TZP zirconia veneers of shade A1 were fabricated with thicknesses of 0.50 mm (n = 25), 0.75 mm (n = 25), and 1.0 mm (n = 25). The translucencies were measured on composite resin teeth with shades A1, A2, A3, A3.5, and A4 using a digital color imaging spectrophotometer. Data were analyzed using ANOVA and post hoc Tukey's test (p < 0.05). Results: The translucency values were optimal for the veneers placed over the substrate teeth with shades A1 and A2, regardless of the veneer thickness. Additionally, veneers with a thickness of 0.50 mm exhibited significantly higher translucency than those with thicknesses of 0.75 mm and 1.0 mm. Conclusions: Our study demonstrated that the translucency of the highly translucent zirconia veneers was influenced by both veneer thickness and tooth shade background. The optimal veneer thickness for achieving the highest translucency was 0.50 for the veneers with A1 and A2 shades placed over the substrate teeth. Clinical Relevance: The optimal thickness for achieving the highest translucency of the highly translucent zirconia laminate veneers was 0.50 mm for the veneers with A1 and A2 shades placed over the substrate teeth. Clinicians and dental technicians could consider this when selecting materials for aesthetic restorations.

A comparative study of translucency and color perception in monolithic zirconia and lithium disilicate veneers.

Ceramic laminate veneers which are a conservative approach to restoring anterior teeth, combining minimal preparation and esthetics. This study aims to evaluate the impact of the thickness of monolithic zirconia laminate veneers on their optical properties and color perception, comparing them to lithium disilicate. A total of 60 laminate veneers were prepared using two ceramic materials, divided into three groups for each material (n = 10) with thicknesses of 0.5, 0.7, and 1.0 mm. CIELab color parameters of the veneers were measured using a spectrophotometer and translucency parameters were calculated. The veneers were cemented onto uniform dies and final L, a, b values of the restorations were measured. The color difference between the different thicknesses was calculated using the CIEDE2000 formula. Two-way ANOVA and Bonferroni HSD post hoc tests were conducted to compare the color parameters (α = 0.05). The results showed that both material type (p < 0.001) and thickness (p < 0.001) influenced translucency values. The translucency values of zirconia veneers were significantly lower than those of lithium disilicate. The color differences (ΔE00) resulting from thickness changes (0.5-1.0 mm) were near or below the perception threshold for lithium disilicate, but distinct for zirconia restorations. In conclusion, monolithic zirconia veneers demonstrated lower translucency compared to lithium disilicate. Changing the material thickness affected the translucency of both materials, but not the color perception only for zirconia.

Facetas em resina composta com fechamento de diastemas para harmonização do sorriso: relato de caso / Composite resin veneers with diastema closure for smile harmonization: A case report / Facetas de resina compuesta con cierre de diastemas para harmonización de la sonrisa: Informe de caso

Introdução:A estética do sorriso é um aspecto valorizado pela sociedade atual, o que demanda que os profissionais de odontologia estejam atualizados sobre materiais dentários e novas técnicas para alcançar resultados estéticos restauradores de alta qualidade. A resina composta é frequentemente utilizada para simplificar a reabilitação oral, pois oferece facetas dentárias que combinam excelente estética e durabilidade. Objetivo:Este artigo tem como objetivo relatar um caso clínico de reabilitação estética utilizando facetas em resina composta com fechamento de diastemas.Relato de caso:Uma paciente do sexo feminino, com 24 anos de idade, procurou a clínica escola de odontologia com insatisfação em relação à estética do seu sorriso. A pacienteapresentava diastemas, restauração defeituosa e desproporção no tamanho dos dentes anteriores. O tratamento consistiu em um clareamento caseiro prévio, seguido pela confecção de facetas diretas em resina composta para fechamento dos diastemas e correção da desproporção dentária. Foram utilizados um Jig Estético e o software Digital Smile Design (DSD)para o planejamento, além de um mock-up em resina bisacrílica. Após a confecção das facetas, foi obtido um resultado estético final satisfatório. O caso incluiu um total de oito facetas,dos dentes 14 ao 24. Conclusão:O tratamento utilizando restaurações em resina composta proporcionou à paciente uma reabilitação estética, funcional e biológica (AU).

Introduction:Smile aesthetics is an aspect valued by today's society, which demands that dental professionals are up to date on dental materials and new techniques to achieve high-quality restorative aesthetic results. Composite resin is often used to simplify oral rehabilitation, as it offers dental veneers which combine excellent aesthetics and durability. Objective:This article aims to report a clinical case of aesthetic rehabilitation using composite resin veneers with diastema closure. Case report:A24-year-old female patient came to the dental school clinic with dissatisfaction regarding the aesthetics of her smile. The patient had diastemas, defective restoration and disproportionate anterior teeth size. The treatment consisted of prior at-home tooth bleaching, followed by creating direct composite resin veneers to close the diastemas and correct tooth disproportion. An Aesthetic Jig and the Digital Smile Design (DSD) software program were used for planning, in addition to a mock-up in bisacrylic resin. After treatment, a satisfactory final aesthetic result was obtained. The case included a total of eight veneers, from teeth 14 to 24. Conclusion:Treatment using composite resin restorations provided the patient with aesthetic, functional and biological rehabilitation (AU).

Introducción: La estética de la sonrisa es un aspecto valorado por la sociedad actual, hecho que demanda de los profesionales de odontología actualización constante sobre los materiales dentarios y nuevas técnicas para alcanzar resultados estéticos restauradores de altacualidad. La resina compuesta es frecuentemente utilizada para simplificar la rehabilitación oral, pues ofrece facetas dentarias que combinan excelente estética y durabilidad.Objetivo: Este artículo tiene como objetivo relatar un caso clínico de rehabilitación estética a partir de la utilización de facetas en resina compuesta con cierre de diastemas. Informe de caso: Una paciente, del sexo femenino, con 24 años de edad, buscó la clínica-escuela de odontología insatisfecha con la estética de su sonrisa. La paciente presentaba diastemas, restauración dentaria defectuosa y desproporción en el tamaño de los dientes anteriores. El tratamiento consistió en un blanqueamiento casero previo, seguido por la confección de facetas directas de resina compuesta para cierre de los diastemas y corrección de la desproporción dentaria. Fueron utilizados un Jig Estético y el software Digital Smile Design(DSD) para el planeamiento, además de un mock-upen resina bisacrílica. Tras la confección de las facetas, fue obtenido un resultado estético final satisfactorio. El caso incluyó un total de ocho facetas, de los dientes 14 al 24.Conclusión: El tratamiento a partir de restauraciones en resina compuesta proporcionó a la paciente una rehabilitación estética, funcional y biológica (AU).

SURVIVAL AND COMPLICATION RATES OF RESIN COMPOSITE LAMINATE VENEERS: A SYSTEMATIC REVIEW AND META-ANALYSIS.

OBJECTIVES: The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers. METHODS: Randomized controlled trials and cohort studies with a minimum 2-year follow-up assessing survival and complication rates of resin composite laminate veneers on permanent dentition from 1998 to May 2022. Literature searches were conducted in MEDLINE (PubMed), Scopus, and the Cochrane Central Register of Controlled Trials electronic databases. References cited in the related reviews and included full-text articles were also hand-searched to further identify potentially relevant studies. RESULTS: A total of 827 articles were identified. Twenty-two studies were considered for full-text review after the title and abstract screening stage. After exclusion, 7 studies (3 randomized controlled trials and 4 cohort studies) were included in the systematic review. Three published scales were adopted for the quality and risk of bias assessment. At the survival rate threshold, the overall heterogeneity (I2) for randomized controlled trials was 50.5% (P = .108). The overall pooled survival rate of the randomized controlled trials was 88% (95% CI: 81%-94%), with the mean follow-up time ranging from 24 to 97 months. Surface roughness, color mismatch, and marginal discoloration were the most reported complications. CONCLUSION: Resin composite laminate veneers demonstrated moderately high survival rates for the entire sample and the direct laminate veneer group demonstrated higher survival rates than the indirect approach. Most of the complications were regarded as clinically acceptable with or without reintervention.

Management of Midline Diastema in a Young Adult With Minimal-Thickness Porcelain Laminate Veneers.

Treating healthy but unaesthetic teeth has been a major challenge for a dental practitioner. Maxillary midline diastemas are one such aberration in the smile zone. Although a diastema can be transient in the developing dentition, the management of the diastema in adulthood requires a detailed examination and appropriate care for a successful outcome. Majority of specialty dentists prefer conservative or minimally invasive treatments, such as porcelain laminate veneer (PLV) restorations over full-ceramic crowns for anterior teeth, where esthetics can be extremely concerning. Minimal-thickness laminate veneers provide a satisfactory outcome while preserving the dental structure as a whole. Thus, this clinical report describes a conservative approach of minimal preparation utilizing a restoration to accomplish both esthetic and functional rehabilitation.

Ceramic versus Composite Resin Polishing Systems on the Surface Roughness of Milled Leucite-Reinforced Ceramics.

Background and Objective: This study aimed to compare the surface finish of milled leucite-reinforced ceramics polished with ceramic and composite polishing systems based on the manufacturers' recommendations. Materials and Methods: Sixty subtractive computer-aided manufactured (s-CAM) leucite-reinforced glass-ceramic specimens (IPS-Empress-CAD) were assigned into six groups: no polishing, a ceramic polishing kit, and four composite kit groups. The roughness average (Ra) was evaluated in microns using a profilometer, and scanning electron micrographs were obtained for qualitative analysis. A Tukey HSD posthoc test (α = 0.05) was used to determine significant intergroup differences. Results: After surface evaluation of the ceramics, the Ra values of the polishing systems ranked OptraFine (0.41 ± 0.26) < Enhance (1.60 ± 0.54) < Shofu (2.14 ± 0.44) < Astropol (4.05 ± 0.72) < DiaComp (5.66 ± 0.62) < No Polishing (5.66 ± 0.74). Discussion: Composite polishing systems did not provide as smooth surfaces as the ceramic polishing kit for CAD-CAM leucite-reinforced ceramics. Thus, using ceramic polishing systems, polishing leucite ceramics is recommended, whereas composite polishing systems should not be considered as an alternative for use in minimally invasive dentistry.

Conocimiento sobre carillas dentales en estudiantes universitarios peruanos

Introducción: las carillas dentales son una opción de tratamiento estético solicitado mayormente para mejorar la apariencia. En Perú, son escasas las investigaciones que miden el conocimiento acerca de este tratamiento. Por ello, el objetivo de este estudio fue determinar el conocimiento sobre carillas dentales en estudiantes de una universidad peruana. Métodos: estudio descriptivo, prospectivo y de corte transversal; conformado por una población de 1417 estudiantes matriculados durante el año 2022 en las Escuelas de Medicina Humana, Psicología y Enfermería de la Universidad Católica Santo Toribio de Mogrovejo, de donde se obtuvo, un tamaño muestral de 160 participantes; sin embargo, fueron 187 quienes respondieron el cuestionario. El instrumento fue previamente validado a través de juicio de expertos y, mediante la prueba Kuder Richardson se obtuvo una confiabilidad alta correspondiente a 0.7. El análisis de datos fue realizado utilizando estadística descriptiva y prueba Chi Cuadrado de Pearson. Resultados: los participantes fueron 55 varones y 132 mujeres. Se reportó un nivel de conocimiento medio sobre el tratamiento con carillas dentales en 75.9% de los estudiantes, y nivel bajo en 5,9% de ellos, la población, en su mayoría obtuvo información de más de una fuente, seguido de redes sociales, amigos y/o familiares, programas de televisión y, finalmente por parte del odontólogo. Conclusión: el conocimiento sobre carillas dentales en estudiantes de una universidad peruana fue de nivel medio, estos resultados fueron similares al ser comparados entre edad, sexo, escuela profesional y fuente de información.

Introduction: dental veneers are an aesthetic treatment option requested mostly to improve appearance. In Peru, there are few investigations that measure knowledge about this treatment. Therefore, the objective of this study was to determine the knowledge about dental veneers in students at a Peruvian university. Methods: descriptive, prospective, and cross-sectional study; made up of a population of 1417 students enrolled during the year 2022 in the Schools of Human Medicine, Psychology and Nursing of the Santo Toribio de Mogrovejo Catholic University, from which a sample size of 160 participants was obtained; however, there were 187 who answered the questionnaire. The instrument was previously validated through expert judgment and, through the Kuder Richardson test, a high reliability corresponding to 0,7 was obtained. Data analysis was performed using descriptive statistics and Pearson's Chi-square test. Results: the participants were 55 men and 132 women. A medium level of knowledge about the treatment with dental veneers was reported in 75,9% of the students, and a low level in 5,9% of them. The population mostly obtained information from more than one source, followed by social networks, friends and / or relatives, television programs and, finally, by the dentist. Conclusion: knowledge about dental veneers in students from a Peruvian university was medium level, these results were similar when evaluated between sex, age, professional school, and source of information.

Ceramic anterior veneer restorations in periodontally compromised patients: A retrospective study.

BACKGROUND: Successful periodontal therapy can lead to poor esthetic results, especially in the anterior region, for which there are treatment options such as direct composite or indirect veneer restorations. Until now, there are no data describing the long-term results of veneer restorations in periodontally treated patients. The aim of this retrospective study was to evaluate the outcome of anterior porcelain veneer restorations in periodontally compromised and noncompromised patients. METHODS: Periodontally healthy and periodontally compromised patients, who had received anterior veneer restorations at least 5 years ago, were invited to a follow-up examination. Groups were divided according to their periodontal diagnosis (periodontally healthy, stage I/II, stage III/IV). Tooth loss, veneer loss, biologic parameters, and complication rates were examined. Also, veneers were evaluated according to modified United States Public Health Service criteria. RESULTS: A total of 68 patients with 312 veneers were examined with a mean follow-up time of 8 years. Veneered teeth in patients with periodontitis stage III/IV showed no difference regarding tooth-specific, overall, and functional veneer survival when compared to periodontally healthy patients (Kaplan-Meier analyses). In Cox regression analysis, follow-up time had an impact on complications and veneer loss, whereas periodontal diagnosis showed no significant influence on the survival of restorations. Comparative tests showed that patients with severe periodontitis at baseline have slightly lower veneer survival rates after 8 years and slightly higher complication rates after 13 years. CONCLUSION: Long-term results and complication rates of veneer restorations in periodontally compromised patients are comparable to periodontally healthy patients over a mean follow-up of 8 years.

An Innovative 3D Printed Tooth Reduction Guide for Precise Dental Ceramic Veneers.

Tooth reduction guides allow clinicians to obtain the ideal space required for ceramic restorations. This case report describes a novel design (CAD) for an additive computer-aided manufactured (a-CAM) tooth reduction guide with channels that permitted access for the preparation and evaluation of the reduction with the same guide. The guide features innovative vertical and horizontal channels that permit comprehensive access for preparation and evaluation of the reduction with a periodontal probe, ensuring uniform tooth reduction and avoiding overpreparation. This approach was successfully applied to a female patient with non-carious lesions and white spot lesions, resulting in minimally invasive tooth preparations and hand-crafted laminate veneer restorations that met the patient's aesthetic demands while preserving tooth structure. Compared to traditional silicone reduction guides, this novel design offers greater flexibility, enabling clinicians to evaluate tooth reduction in all directions and providing a more comprehensive assessment. Overall, this 3D printed tooth reduction guide represents a significant advancement in dental restoration technology, offering clinicians a useful tool for achieving optimal outcomes with minimal tooth reduction. Future work is warranted to compare tooth reductions and preparation time for this guide to other 3D printed guides.

Ultra-Translucent Zirconia Laminate Veneers: The Influence of Restoration Thickness and Stump Tooth-Shade.

This in vitro study aimed to evaluate the final shade of translucent zirconia laminate veneers with varying thicknesses over teeth with different shades. Seventy-five chairside computer-aided design/computer-aided manufacturing (CAD/CAM) shade A1 third-generation zirconia dental veneers, with thicknesses of 0.50 mm, 0.75 mm, and 1.00 mm, were placed on resin composite teeth with shades ranging from A1 to A4. The laminate veneers were divided into groups based on thickness and background shade. All restorations were evaluated with a color imaging spectrophotometer, to map the veneer surface from A1 to D4. Regardless of the thickness or background shade, all dental veneers showed color alteration from the original shade. Veneers with 0.5 mm thickness tended to display the B1 shade, while veneers with 0.75 mm and 1.0 mm thickness primarily exhibited the B2 shade. The thickness of the laminate veneer and background shade significantly modified the original shade of the zirconia veneer. One-way analysis of variance was performed and a Kruskal-Wallis test was used to determine the significance between the three veneer thicknesses groups. The results indicated that the thinner restorations showed higher values with the color imaging spectrophotometer, suggesting that thinner veneers may result in more consistent color matching. This study underscores the importance of carefully considering thickness and background shade when selecting zirconia laminate veneers, to ensure optimal color matching and overall aesthetic outcomes.

Minimally Invasive Laminate Veneer Therapy for Maxillary Central Incisors.

Minimally invasive dentistry is a considered process that requires the clinician to be prepared with the ideal sequence and the tools needed. This report describes a well-planned ultraconservative approach using only two ceramic laminate veneers for the maxillary central incisors to significantly improve the patient's overall smile. A 30-year-old female presented with the chief complaints of having diastemas between the central and lateral incisors as well as incisal wear. Diagnostic wax-up and mock-up were performed, and the patient approved the minimally invasive treatment with veneers only for central incisors. A reduction guide aided the conservative tooth preparations, and hand-crafted feldspathic veneers were bonded under total isolation with a rubber dam. The two final conservative veneers significantly improved the smile and fulfilled the patient's expectations. Following proper planning and sequencing, predictable outcomes were obtained and fulfilled the patient's esthetic demands. Minimally invasive restorative dentistry with only two single veneers can impact the entire smile frame. Overtreatment in the esthetic zone is unnecessary to meet a patient's esthetic expectations.

Porcelain Veneers in Vital vs. Non-Vital Teeth: A Retrospective Clinical Evaluation.

Nowadays, the ceramic veneer approach can be considered more predictable than direct composite veneer. To date, there is a lack of studies comparing the clinical performance of anterior veneers cemented on vital teeth (VT) and non-vital teeth (NVT). This longitudinal clinical study investigated the performance of ceramic veneers in VT or anterior NVT. A total of 55 patients were evaluated in the study. Two groups were defined based on the vitality status of the teeth (93 teeth-vital and 61 teeth-non-vital). The United States Public Health Service (USPHS) criteria were used to assess the clinical status. The data were evaluated statistically with the Mann-Whitney U test. All restorations were considered acceptable, and only one veneer in VT failed for the criteria of secondary caries. There were no statistically significant differences in any of the criteria evaluated (p ≤ 0.671). The ceramic veneers evaluated showed a satisfactory clinical performance both in VT and NVT.

Invisible treatment of an asymmetric adult class II malocclusion related to unilateral upper lateral incisor agenesis with a straight wire lingual appliance, mini-screw and premolar extraction: A case report.

This case report describes a complex full-step class II malocclusion with unilateral upper lateral incisor agenesis in an adult patient treated with lingual straight-wire appliance and premolar extraction, with the two-fold aim of obtaining ideal occlusal relationship and smile aesthetic improvement. In view of this, it underlines how an appropriate treatment strategy, including extraction choice and anchorage control during space closure, is needed to achieve the planned results with a completely invisible lingual appliance combined with aesthetic veneers.

Thickness and Substrate Effect on the Mechanical Behaviour of Direct Occlusal Veneers.

PURPOSE: This study aimed to evaluate the fracture resistance and stress magnitude of occlusal veneers made of conventional or flowable resin composites at different minimal thicknesses bonded on enamel or dentin. MATERIAL AND METHODS: A total of 120 sound bovine incisors were flattened and used as substrates (enamel or dentin) for the restorations. The teeth were embedded into polymethyl methacrylate and allocated into 4 groups according to the resin composite (Clearfil AP-X PLT and Clearfil Majesty Flow, Kuraray Dental) and substrate. Further, the substrates were randomly subdivided in 12 groups (N = 120, n = 10) according to the occlusal veneer minimal thickness: 0.5, 1.0, or 2.0 mm. The teeth were directly restored with a standardised procedure. Then, the specimens were loaded until fracture in a universal testing machine (Instron 6022, Instron Corp.). A 3-way and a 1-way analysis of variance were used to determine significant differences for each factor. Three-dimensional finite element analysis was carried out following the in vitro boundary conditions to assess the stress magnitude in the restoration during compressive loading. RESULTS: The fracture loads were recorded into initial load to failure (ILF) and fatal load to failure (FLF). Differences were found in material for ILF and FLF, leading to an overall equal good performance in fracture load and stress distribution for both materials, regardless of the substrate. Differences in thickness were apparent in both ILF and FLF. CONCLUSIONS: Direct conventional and flow resin composite occlusal veneers present a promising mechanical behaviour when bonded on enamel or dentin. However, caution is advised when preparing 0.5-mm minimal thickness restorations.

Anterior esthetic rehabilitation with full and partial veneers using conventional and digital techniques: A case series.

Effective esthetic rehabilitation requires a proper treatment planning in addition to the associated diagnostic wax-up. For anterior rehabilitation, most dentists favor conservative and esthetic treatments, such as indirect laminate veneer restorations which can be partial- or full-ceramic anterior crowns according to the clinical situations. After the introduction of technologies such as intraoral scanners, dental software for digital restoration design, and additive manufacturing (three-dimensional printing), these techniques further enhanced the digital workflow of restorative therapy. These technologies also fabricate prosthesis with natural esthetics and marginal integrity. This case series discusses the conventional and digitally fabricated full- and partial-ceramic veneers for discolored and misaligned anterior teeth after the fabrication of corresponding diagnostic wax-up.

Marginal Adaptation of Veneers: A Systematic Review.

This study aimed to systematically review the literature to evaluate the marginal adaptation of veneers using different fabrication methods, namely, conventional feldspathic porcelain laminate veneers (PLVs), computer-aided design-computer-aided machining (CAD-CAM) veneers, and pressed veneers. A comprehensive literature search was performed using electronic databases (PubMed and Google Scholar) as well as hand searches to identify all relevant studies related to veneers and marginal adaptation. The identified studies were screened for assessing the inclusion and exclusion criteria. The included articles were then subjected to data extraction and analysis. The search resulted in 130 articles, of which six were included in this systematic review. All included articles were assessed for adaptation of margins. Based on the findings of this systematic review, no significant differences were found in the marginal adaptation of CAD-CAM and conventional feldspathic PLVs. The marginal fidelity of ceramic veneers issuing from the various fabrication techniques was clinically acceptable.

The efficiency of ErCr: YSGG laser on the debonding of different thicknesses of ceramic veneers

Aims: To verify the efficacy of Er,Cr:YSGG laser for debonding of lithium disilicate (LD) reinforced glass ceramic veneers of different thicknesses. Methods: Forty bovine teeth were prepared and randomly divided into four groups (n=10/group) according to the ceramic disc thickness: C0.5 (Control group) and L0.5 (Laser irradiated group) in which LD discs had a thickness of 0.5mm and 5mm diameter; C1 and L1 in which LD discs had a thickness of 1mm and 5mm diameter. The lithium disilcate discs (IPS E.max®, shade HTA2) were fabricated following the manufacturer's recommendations and cemented to the prepared tooth surface. The Er,Cr:YSGG laser was applied to the laser groups at 2.5W and 25Hz for 60seconds. Universal testing machine was used to evaluate the shear bond strength for all samples at a cross head speed of 1mm/min in an inciso-gingival direction parallel to the sample surface. After debonding, the samples were examined under stereoscope to evaluate the mode of failure according to the adhesive remnant index (ARI). Results: Laser irradiation significantly diminishes the shear bond strength from 10.868 MPa to 3.778 MPa for C0.5 and L0.5 groups respectively (p=0.00) and from 14.711 MPa to 4.992 MPa for C1 and L1 groups respectively (p=0.00). The shear bond strength required for debonding increased with increasing thickness of discs, but without significant difference (p=0.110). Higher ARI scores were seen in the laser groups (more cement remaining adhered to the tooth) when compared to the control groups. Conclusions: The Er,Cr:YSGG laser could be an effective and useful tool in debonding of lithium disilicate ceramic veneers as it decreases the shear bond strength required for veneer debonding

Load-bearing capacity of pressable lithium disilicates applied as ultra-thin occlusal veneers on molars.

PURPOSE: The aim was to investigate the load bearing capacity of different pressable lithium disilicates cemented as occlusal veneers on molars. MATERIALS AND METHODS: One control group and six test groups were formed consisting of 20 specimens each (n = 20). The six test groups differed in the utilizing pressable lithium disilicate to fabricate occlusal veneers. As a control group, "group Lis", the lithium disilicate with the highest reported flexural strength was used (initial LiSi Press, GC Europe; Leuven, Belgium / flexural strength: 508 MPa). The test groups consisted of other pressable lithium disilicates with lower flexural strength values: "Ema" (IPS e.max press), "Vit" (VITA Ambria), "Liv" (Livento Press), "Amb" (Amber Press), "Mas" (Amber Press Master) and "Ros" (Rosetta SP)". After the preparation of 140 extracted human molars, which included the removal of the central enamel, the specimens were scanned using a desktop scanner. With the aid of a design software, the occlusal veneers were designed in a standardized thickness of 0.5 mm. To fabricate the restorations, all tested materials were processed using heat-pressing technique. All restorations were adhesively cemented. Afterwards, the specimens underwent cyclic fatigue during an aging procedure in a chewing simulator (1'200'000 chewing-cycles, 49 N force, 5-55°C temperature changes). Subsequently, the specimens were statically loaded and the load which was necessary to fracture the specimen (Fmax) were measured. Differences between the groups were compared applying the Kruskal-Wallis (KW) test and the Wilcoxon-Mann-Whitney-Test (WMW: p < 0.05). The two-parameter Weibull distribution values were calculated. RESULTS: The fatigue resistance was 100% for the groups Lis, Vit, Liv, Amb, Mas and Ros, whereas the group Ema showed a fatigue resistance of 95%. The control group Lis showed median Fmax values of 2'328 N. The median Fmax values for the test groups ranged between 1'753 N (Vit) and 2'490 N (Ros). Statistically significant difference was observed among the groups Lis (control) and Vit (KW: p < 0.001). Weibull distribution presented the highest shape values for the group Ros (12.83) and the lowest values for the group Ema (4.71). CONCLUSION: Regarding their load-bearing capacity different pressable lithium disilicates can be recommended to fabricate ultra-thin occlusal veneers on molars when restoring occlusal tooth wear.

Smile Transformation with Composite Resin by Semi-Direct Technique: a Case Report / Transformação Do Sorriso Com Resina Composta Por Técnica Semi-Direta: Relato De Caso

Composite veneers stand out in modern dentistry for their practicality, time-saving and excellent optical properties. This work describes the operative steps for the realization of veneers in composite resin in an academic clinical environment using a semi-direct technique. A 21-yearold female patient attended the clinic-school complaining of aesthetic dissatisfaction with her smile. In the clinical dental evaluation, multiple diastemas were observed in the upper anterior teeth, and resin cement residues from orthodontic bracket bonding. In addition, the patient expressed an interest in having bigger and whiter teeth. In view of the complaints reported by the patient, the following treatment sequence was proposed: 1. Removal of residual resin cement from all teeth; 2. Tooth whitening; 3. Confection of composite resin veneers using the semi-direct technique on the upper teeth (canine to canine). The die stone that had already been made for the home bleaching procedure was used for esthetic rehabilitation. The 6 veneers were made using a nanoparticulate resin. The veneers were cemented and adjusted. The 12-month follow-up showed an excellent marginal adaptation and an excellent aesthetic and function quality. The semi-direct technique may be considered a therapeutic option based on the conservation of sound tooth structure, minimal emotional stress during clinical work and excellent final optical and mechanical properties. Simplicity and practicality of the technique allow reproducibility and excellent results at a lower cost when compared to dental ceramics. (AU)

As facetas em resina composta destacam-se na odontologia moderna por sua praticidade, economia de tempo e excelentes propriedades ópticas. Este trabalho descreve as etapas operatórias para a realização de facetas em resina composta em ambiente clínico acadêmico utilizando a técnica semi-direta. Paciente do sexo feminino, 21 anos, compareceu à clínica-escola com queixa de insatisfação estética com seu sorriso. Na avaliação clínica odontológica, foram observados múltiplos diastemas nos dentes anteriores superiores e resíduos de cimento resinoso proveniente da colagem de braquetes ortodônticos. Além disso, a paciente manifestou interesse em ter dentes maiores e mais brancos. Diante das queixas relatadas pela paciente, foi proposta a seguinte sequência de tratamento: 1. Remoção do cimento resinoso residual detodos os dentes; 2. Clareamento dental; 3. Confecção de facetas de resina composta pela técnica semi-direta nos dentes superiores (canino a canino). O modelo de gesso já confeccionado para o clareamento caseiro foi utilizado para a reabilitação estética. As 6 facetas foram confeccionadas utilizando resina nanoparticulada. As facetas foram cimentadas e ajustadas. O seguimento de 12 meses mostrou uma excelente adaptação marginal e uma excelente qualidade estética e funcional. A técnica semi-direta pode ser considerada uma opção terapêutica baseada na conservação da estrutura dentária sadia, mínimo estresse emocional durante o trabalho clínico e excelentes propriedades ópticas e mecânicas finais. A simplicidade e praticidade da técnica permitem reprodutibilidade e excelentes resultados a um custo menor quando comparado às cerâmicas odontológicas. (AU)

Evaluation of color change before and after polymerization of laminate veneer restorations: A clinical study.

Background and Aim: The purpose of this in vivo study was to investigate the effect of translucent adhesive resin cement on the final color of ceramic laminate veneer restoration before and after polymerization in intraoral conditions. Materials and Methods: This study was conducted in 92 ceramic laminate veneer restorations of 27 patients. The ceramic laminate veneer restorations in standard thickness lithium disilicate ceramic structure (IPS e.max Press HT, Ivoclar Vivadent) were cemented to the tooth with translucent light-polymerized resin cement (Choice 2 Starter Kit, Bisco). Results: It was observed a clinically noticeable color change between ΔE values before and after polymerization (ΔE >3.3). There was a statistically significant difference in b* values, ΔL value, and Δb value. Conclusion: Within the limitations of this in vivo study, the results suggest that light polymerization of the translucent resin cement (Choice 2, Bisco) used is an important factor for the final color of the restoration and should be considered during shade selection and fabrication.