Clinical outcomes of self-glazed zirconia veneers produced by 3D gel deposition: a retrospective study.

BACKGROUND: Self-glazed zirconia (SZ) restorations are made by a novel additive three-dimensional gel deposition approach, which are suitable for a straightforward completely digital workflow. SZ has recently been used as minimally invasive veneer, but its clinical outcomes have not been clarified yet. This study aimed to evaluate the preliminary clinical outcomes of SZ veneers compared with the widely used lithium disilicate glass-ceramic veneers made by either pressing (PG) or milling (MG) process. METHODS: Fifty-six patients treated with SZ, PG, and MG veneers by 2 specialists between June 2018 and October 2022 were identified. Patients were recalled for follow-up at least 1 year after restoration. Clinical outcomes were assessed by 2 independent evaluators according to the modified United States Public Health Service (USPHS) criteria. Overall patient satisfaction was assessed using visual analogue scale (VAS), and analyzed by one-way ANOVA. Chi-square test was applied to compare the difference in the success and survival rates among the 3 groups. RESULTS: A total of 51 patients restored with 45 SZ, 40 PG, and 41 MG veneers completed the study, with a patient dropout rate of 8.9%. Mean and standard deviation of follow-up period was 35.0 ± 14.7 months. All restorations performed well at baseline, except for 2 SZ veneers with mismatched color (rated Bravo). During follow-up, marginal discrepancy (rated Bravo) was found in 4 MG veneers and 1 PG veneer, and partially fractured (rated Charlie) was found in another 2 PG veneers. The survival rate of SZ, PG, and MG veneers was 100%, 95%, and 100%, with a success rate of 95.56%, 92.50%, and 90.24%, respectively, none of which were significantly different (p = 0.099 and 0.628, respectively). The mean VAS score of SZ, PG, and MG was 95.00 ± 1.57, 93.93 ± 2.40, and 94.89 ± 2.00 respectively, without significant difference (p > 0.05). CONCLUSION: SZ veneers exhibited comparable preliminary clinical outcomes to PG and MG veneers, which could be considered as a feasible option for minimally invasive restorative treatment.

Tetracycline staining of the dentition: a review of the literature and report of a clinical case.

The present article reviews the literature regarding tetracycline staining of the dentition and its esthetic management. A total of 49 articles were identified in the initial search, and 22 articles met the eligibility criteria of this narrative literature review. Tetracycline staining results from its use in children between the ages of 6 months and 6 years, when tooth crowns are formed; the effects are dependent on the dosage, duration of treatment, stage of tooth mineralization, and activity of the mineralization process. Tooth bleaching is always the first treatment option for low-grade cases of tetracycline staining. Restorative procedures are indicated for severe staining. The article also describes the treatment of severe staining affecting the maxillary anterior dentition of a 48-year-old man who reported the systemic administration of tetracycline during childhood. Direct composite resin laminate veneers were proposed to achieve immediate, highly esthetic restorations. A combination of different resinous materials in different shades was applied to meet the needs of the patient. The use of direct composite resin laminate veneers satisfied the functional and esthetic demands of the patient at a lower cost than ceramic materials.

Componeer as an aesthetic treatment option for anterior teeth: a case report.

INTRODUCTION: Structural abnormalities or anomalies in the anterior teeth, also known as the aesthetic zone, are an important problem for patients and a challenge for dentists. Structural abnormalities or tooth anomalies can change in color, shape, and function. Most dentists prefer minimally invasive aesthetic treatment. One of the aesthetic treatment options for anterior teeth is veneers. Veneer is a restoration that covers the labial part of the tooth with a thin layer of material to correct abnormalities in the color, shape, or function of the tooth. Veneer restoration can be done indirectly with porcelain material made in a laboratory and directly with composite material on the tooth surface or prefabricated which is available from the factory. Componeer is a prefabricated composite veneer that combines the aesthetic properties of ceramic veneers and the adhesive ability of composite veneers to the tooth structure. This case report describes the treatment of two central incisors that had been filled with composite and peg shapes on both lateral incisors using a componeer. CASE REPORT: A 32-year-old female patient came to the Dental Conservation Clinic at Dentistry Hospital, Padjadjaran University with the main complaint of her right and left upper front teeth and wanted to repair her old fillings and close the gap between her right and left upper front teeth and her canine teeth. Clinical examination showed that teeth 11 and 21 had been filled with composite which had changed color and had an inharmonious shape as well as a gap between the upper front teeth on the right and left sides and the right and left canine teeth. TREATMENT: The maxilla and mandibular teeth are molded for study models and working models. In the working model, a wax-up is carried out, then a mock-up on the patient's teeth. Next, choose the color and size of the components that match the mock up results. Teeth 11 and 21 had their old composite fillings cleaned and refilled with dentin colored composite, teeth 13, 12, 11, 21, 22, and 23 were prepared with a minimum thickness of 0.3 mm to make room for the componeer material. The teeth was etched and bonded, and bonding was applied to the inner surface of the componeer. The composite is placed on the inner surface of the componeer then placed on the labial surface of the tooth and pressed with a special tool, then light cured. The final step is polishing. TREATMENT RESULTS: Teeth 13, 12, 11, 21, 22, and 23 which had undergone veneer treatment using componeer, were controlled after 1 week of treatment. The patient did not complain about the results of the treatment and said he was satisfied with the treatment.

Preparation of ultrathin translucent zirconia laminate veneers using 3D printing reduction guides.

Minimizing and controlling the amount of tooth reduction during the preparation of ultrathin laminate veneers is a challenge for minimally invasive dentistry. The use of reduction guides is advised to reach the optimal space required for the definitive restoration without excessive reduction. The digital production of a reduction guide used to control tooth preparation for ultrathin laminate veneers is described.

Fracture strength of porcelain veneer on surface-treated zirconia.

In this study, we investigated the effects of surface treatment on the fracture strength of porcelain-veneered zirconia. Highly translucent 4 mol% yttria-stabilized zirconia disks (KATANA HT, Kuraray Noritake Dental) were divided into three surface-treatment groups: 1)as-sintered, 2) alumina sandblasted, and 3) ground. Crystallographic and surface-roughness analyses were conducted for each group. Veneering ceramics (Cerabien ZR, Kuraray Noritake Dental) were applied to the zirconia surfaces. The fracture strengths of the porcelain-veneered zirconia disks were measured using biaxial flexural-strength tests. Crystallographic analysis revealed that grinding and sandblasting increased the fractions of the monoclinic and rhombohedral zirconia phases. The ground specimens had a higher surface roughness than the sandblasted specimens. Weibull analysis showed no significant differences in biaxial flexural strength among the three groups. The results suggest that these surface treatments do not affect the fracture strength of porcelain-veneered zirconia.

Fracture Resistance and Failure Mode of Monolithic Zirconia, Veneered Zirconia, and Metal-Ceramic Full-Coverage Restorations: A Comparative In Vitro Study.

PURPOSE: To evaluate and compare the fracture mode and strength of monolithic zirconia to veneered zirconia and metal-ceramic full-coverage restorations following artificial aging and to test the performance of translucent zirconia in terms of load-bearing capacity. MATERIALS AND METHODS: Two mandibular first molars were prepared and scanned for their respective groups of full-coverage restorations. A total of 75 full-coverage restorations were fabricated and divided into five groups: two groups for monolithic zirconia, two groups for veneered zirconia, and one group for metal-ceramic. Then, 75 light-cured hybrid composite resin dies were fabricated to serve as abutments. Before cementation, all full-coverage restorations were subjected to accelerated aging. After cementation, all full-coverage restorations were subjected to compressive loading until fracture in an electromechanical universal testing machine. A two-way nested ANOVA and Tukey test were used to analyze the results with 95% confidence levels. RESULTS: Monolithic zirconia full-coverage restorations showed the highest mean fracture resistance of 4,201.0 N, followed by metalceramic full-coverage restorations of 3,609.3 N, and veneered zirconia full-coverage restorations showed the lowest mean fracture resistance of 2,524.6 N. The main mode of failure was cohesive bulk fracture for the monolithic zirconia group, cohesive/adhesive failure with infrastructure damage for the veneered zirconia group, and cohesive/adhesive failure without infrastructure damage for the metal-ceramic group. CONCLUSIONS: Monolithic zirconia full-coverage restorations showed superior resistance to fracture compared to metal-ceramic full-coverage restorations and are highly reliable in terms of load-bearing capacity within the posterior regions of the mouth.

Effect of porcelain veneering technique in bilayered zirconia on bond strength and residual stress distribution.

The use of all porcelain materials in dentistry has significantly increased in recent years. However, chipping has remained a common problem that affects bilayered zirconia restorations. Bonding between porcelain and the underlying zirconia framework is crucial to the success of the restoration. The bond strength may be affected by such factors as residual thermal stress and the veneering technique. This research focuses on investigating the potential and constraints of materials through an examination of the porcelain veneering technique, particularly hand-layering and heat-pressing. Forty-two cylindrical disc samples of zirconia (n = 7/group) were fabricated in the dimensions of 10 × 1.2 mm (diameter [D] × height [H]). The zirconia specimens were milled from IPS e.max® ZirCad [Z] block and Luxen Zr [L] block (n = 21/zirconia). The zirconia cores were layered with IPS e.max® Zirliner and heat-pressed with IPS e.max® ZirPress to produce a final veneer dimension of 5 × 3 mm (D × H). Conventional layering was performed for the rest of the zirconia cores using IPS e.max® Ceram and Shofu Vintage Zr. The final study groups were Luxen-Vintage (LV), Luxen-Ceram (LC), Luxen Zirpress (LP), ZirCad-Vintage (ZV), ZirCad-Ceram (ZC) and ZirCad-Zirpress (ZP). Five samples were subjected to shear bond testing (SBS) with a universal testing machine with a 5 kN load cell and 0.5 mm/min crosshead speed (n = 5/group). A sample underwent nanoindentation, and another was sectioned using Isomet machine to study the bonding interface. One-way ANOVA was used to run the statistical analyses of the SBS test. Statistical differences were found between ZV with LC and LP (p < 0.05). Residual stress is estimated to be higher in the middle of the porcelain compared with that on the surface and the interface. FESEM imaging reveals portions of visible bare zirconia on Luxen zirconia, whilst crack propagation occurred through voids in all hand-layered groups. Heat-pressed veneering showed comparable but not superior results to conventional hand-layered veneering. Heat-pressed veneering produced similar stress distribution profiles compared with hand-layered veneering.

Extended porcelain veneers in the maxillary anterior region.

AIM: The aim of the present retrospective study was to evaluate the long-term results, including technical and biologic outcomes, of maxillary extended porcelain veneers with an incisal edge thickness above 2 mm. MATERIALS AND METHODS: Patients treated with extended porcelain veneers performed by a single clinician at University of Geneva between 1990 and 2003 were identified and invited to an examination. Of the 37 identified patients, 10 patients with 50 veneers agreed to be examined and were included. A clinical examination was performed to assess survival rates as well as technical and biologic outcomes (modified United States Public Health Services criteria). Patient records were also reviewed to retrieve patient and reconstruction data and every complication event. Patient-reported outcome measures (PROMs) were evaluated using a visual analog scale to measure esthetic satisfaction, functional and phonetic comfort, masticatory improvement, tooth sensitivity, and acceptance of restoration replacement in case of failure. Data were descriptively analyzed, and Kaplan-Meier survival estimators were computed for survival rates and complication events. RESULTS: The survival rate of the veneers was 96% after a mean follow-up of 20.7 ± 3.7 years in function. The technical complication rate amounted to 30%, including two failures, nine repairable fractures, three cracks, and one displacement due to trauma. No cavitated caries lesions or endodontic complications were registered. PROMs were very high for esthetic satisfaction and phonetic comfort. CONCLUSIONS: Within the limitations of the present retrospective study, extended porcelain veneers appear to be a successful long-term treatment option in terms of clinical outcomes and patient satisfaction.

Effect of a modified laminate veneer preparation design on absolute margin discrepancy and marginal overhang.

STATEMENT OF PROBLEM: Veneer preparation designs impact veneer accuracy. However, whether a modified design could reduce absolute margin discrepancy and marginal overhangs is unclear. PURPOSE: The purpose of this in vitro study was to investigate whether a modified veneer preparation design enhances the absolute margin discrepancy and marginal overhang. MATERIAL AND METHODS: The absolute margin discrepancy and the marginal overhang of 3 different veneer preparation designs on a typodont tooth (n=20): feather edge, shoulder, and shoulder with wings were measured. The feather edge design was prepared first and subsequently modified to create the shoulder and shoulder with wings preparations. Ceramic veneers were fabricated using computer-aided design and computer-aided manufacture with each veneer assessed for fit before cementation. Ten specimens were cut vertically, and 10 were cut horizontally in each group. The absolute margin discrepancy and marginal overhangs were measured for each cross-section with scanning electron microscopy. Descriptive data analysis and hypothesis testing were conducted using the nonparametric Kruskal Wallis test (α=.05). RESULTS: On the vertical sections, the shoulder with wings preparation had the best absolute margin discrepancy and overhang. The design was also best for mesial overhang and mesial absolute margin discrepancy when measuring horizontally. CONCLUSIONS: The shoulder with wings preparation design produced the smallest cervical absolute margin discrepancy and overhang. This design also produced absolute margin discrepancy and overhangs comparable with those of the shoulder design in the proximal areas.

Influence of ceramic thickness and dental substrate on the survival rate and failure load of non-retentive occlusal veneers after fatigue.

OBJECTIVE: To investigate the effect of ceramic thickness and dental substrate (enamel vs. dentin/enamel) on the survival rate and failure load of non-retentive occlusal veneers. MATERIALS AND METHODS: Human maxillary molars (n = 60) were divided into five test-groups (n = 12). The groups (named DE-1.5, DE-1.0, DE-0.5, E-1.0, E-0.5) differed in their dental substrate (E = enamel, DE = dentin/enamel) and restoration thickness (standard: 1.5 mm, thin: 1.0 mm, ultrathin: 0.5 mm). All teeth were prepared for non-retentive monolithic lithium-disilicate occlusal veneers (IPS e.max Press, Ivoclar). Restorations were adhesively cemented (Syntac Classic/Variolink II, Ivoclar) and exposed to thermomechanical fatigue (1.2 million cycles, 1.6 Hz, 49 N/ 5-55°C). Single load to failure was performed using a universal testing-machine. A linear-regression model was applied, pairwise comparisons used the Student-Newman-Keuls method (p < 0.05). RESULTS: Three dentin-based occlusal veneers (one DE-1.0, two DE-0.5) revealed cracks after fatigue exposure, which corresponds to an overall-survival rate of 95%. Load to failure resulted in the following ranking: 2142 N(DE-0.5) > 2105 N(E-1.0) > 2075 N(E-0.5) > 1440 N(DE-1.5) > 1430 N(DE-1.0). Thin (E-1.0) and ultrathin enamel-based occlusal veneers (E-0.5) revealed high failure loads and surpassed the standard thickness dentin-based veneers (DE-1.5) significantly (p = 0.044, p = 0.022). CONCLUSION: All tested monolithic lithium disilicate occlusal veneers obtained failure loads above physiological chewing forces. Thin and ultrathin enamel-based occlusal veneers outperformed the standard thick dentin-based occlusal veneers. CLINICAL SIGNIFICANCE: Minimally invasive enamel-based occlusal veneer restorations with non-retentive preparation design may serve as a conservative treatment option.

Ceramic veneer shade evaluation using a multicolored 3D-printed model-A case report.

OBJECTIVE: This article demonstrates the use of a multicolored 3D-printed model for laboratory shade evaluation of ceramic veneers. CLINICAL CONSIDERATIONS: A young female patient presented with peg lateral incisors and diastemata between her maxillary incisors. Four ceramic veneers for her maxillary incisors were fabricated using a digital workflow. A multicolored 3D-printed model was manufactured using material jetting technology. The multicolored model and try-in pastes were used to evaluate and adjust the shade of the veneers. Clinically acceptable color matching was achieved, the veneers were delivered without further chairside shade adjustments. CONCLUSIONS: Successful color evaluation and adjustment were achieved using the combination of multicolored 3D-printed model and try-in pastes. The use of this approach saved time for stump shade taking and fabrication of tooth-colored dies. CLINICAL SIGNIFICANCE: A multicolored 3D-printed model can be a useful tool for color evaluation and adjustment of ceramic restorations.

Quo vadis, esthetic dentistry? Part II: Composite resin overtreatment and social media appeal.

OBJECTIVES: This article presents case reports highlighting over-treatments with resin composites, often misconceived as minimally invasive procedures. CLINICAL CONSIDERATIONS: Tooth-colored restorative materials, such as ceramics and composites, have found widespread application to correct problems related to tooth color, shape, and alignment. When composite resin is used, these procedures can be done in a very conservative, cost-effective, and timely fashion. However, it is noteworthy that contemporary dental esthetic expectations are based on standards propagated by social media and other marketing and communications platforms. The abuse of and addiction to social media impacts can lead to unrealistic esthetic expectations and standards for both patients and dentists. CONCLUSIONS: After a critical discussion on ceramic veneers published in part I of this 2-part series, this article directs attention towards what has become a trendy fashion, i.e., the use of direct composite resins as "non-prep" veneers in clinical situations that arguably required no restorative intervention at all. We further explore how social media influences the decision-making processes of both professionals and patients.

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).

Influence of an internal firing of feldspathic porcelain before or after sintering on adaptation of high-translucent zirconia laminate veneers.

The aim of the present study was to evaluate the influence of two different internal surface treatments, namely, the firing of feldspathic porcelain before or after zirconia sintering, on the marginal and internal adaptation of laminate veneers (LVs) made of high-translucent zirconia. A total of 33 zirconia LVs were fabricated using a CAD/CAM system and divided into three groups based on the internal surface treatment method: the pre-firing (PRE) group involved firing feldspathic porcelain before zirconia sintering, the post-firing (POS) group involved firing feldspathic porcelain after zirconia sintering, and the no treatment (NT) group involved no application of feldspathic porcelain. The adaptation of the LVs was measured using a silicone replica technique. Data were analyzed using the Kruskal-Wallis and Steel-Dwass tests (α = .05). The POS group showed significantly higher marginal discrepancy values than the PRE group across all sites. The internal space values of the PRE groups were significantly lower than those of the NT group at all sites. The internal firing of feldspathic porcelain before zirconia sintering resulted in better marginal adaptation of the high-translucent zirconia LVs than the internal firing of feldspathic porcelain after zirconia sintering. The internal firing of feldspathic porcelain before zirconia sintering can achieve uniform internal adaptation of high-translucent zirconia LVs.

The challenge of ceramic restorations on dark substrate: a case report.

The use of dental ceramics on anterior teeth is associated with predictable and long-lasting esthetic results. However, treatment on darkened substrates is challenging. Various conservative options, including ceramic veneers, are available to change the shape and color of anterior teeth. The aim of this case report is to describe the esthetic rehabilitation of a darkened central incisor in a maxillary anterior region that had irregular gingival contours, multiple composite resin restorations, and unsatisfactory tooth shapes. Harmony was restored through periodontal recontouring surgery, placement of a lithium disilicate crown (consisting of a veneer cemented to a coping) on the darkened central incisor, and placement of lithium disilicate veneers on the other maxillary anterior teeth.

Printed Digital Wax-up Model as a Blueprint for Layered Pressed-ceramic Laminate Veneers: Technique Description and Case Report.

This article presents a clinical technique for transferring Digital Smile Design (DSD) information and a digital wax-up to fabricate highly personalized ceramic laminate veneers. The hybrid workflow of digitally designed wax-up and conventional hand-crafted veneers is showcased in a female adult who sought to improve her smile due to maxillary anterior incisal wear. The ceramic veneers, layered by feldspathic porcelain, followed the contours and shade blueprint planned with the digital wax-up. The DSD improved the harmony of the facial-and-smile relationship, and the ceramic restorations fulfilled the patient's esthetic and functional demands. Guides based on the printed model with the digitally designed wax-up can provide a reference for pressed lithium disilicate veneers layered with feldspathic porcelain.

The removal of three kinds of occlusal veneers by Er: Yag laser.

OBJECTIVES: This study aimed to remove occlusal veneers of varied thicknesses and compositions by Er:Yag laser in vitro and analyze the interfacial microstructure between veneers and tooth that irradiated by laser, by which experimental evidence could be provided to support the non-invasive removal of occlusal veneerby laser. METHODS: Fresh mandibular premolars extracted for orthodontic requirements were collected for tooth preparation. Three kinds of ceramic materials (Vita Suprinity, Vita Mark Ⅱ, and Upcera Hyramic) were selected to fabricate occlusal veneer with different thicknesses (1.0, 1.5, and 2.0 mm). One week later, Er:Yag laser (2.5 W and 3.5 W) was used to irradiate and remove the occlusal veneer and recorded the timespan. After the removal operation, the micro-morphologies of samples were examined by scanning electron microscope. RESULTS: Upcera Hyramic veneer failed to be removed (>20 min); the operation span at 2.5 W, Vita Suprinity (96.0 s±16.0 s) was longer than Vita MarkⅡ(84.5 s±19.5 s) in the 1.0 mm group (P<0.05), and Vita Suprinity (246.5 s±13.5 s) was longer than Vita MarkⅡ(170.0 s±14.0 s) in the 1.5 mm group (P<0.05). At 3.5 W, Vita Suprinity (381.0 s±24.0 s) was longer than Vita MarkⅡ(341.5 s±26.5 s) in the 2.0 mm group. CONCLUSIONS: Increasing laser power could shorten the operation span and facilitate the removal of occlusal veneers with the same thickness and composition. The occlusal veneer was sustained when insufficient laser power was applied. With the same laser power and ceramic thickness, laser penetration could interfere with the integral of the ceramic structure when the laser interacted with the bonding layer. With the same ceramic composition and laser power, the operation span and laser power increased with the thickness of the occlusal veneer. However, the laser was incapable of removing occlusal resin veneer directly.

[Evaluation of red and white aesthetic effects of porcelain veneers in the restoration of developmental anterior dental gaps].

PURPOSE: To evaluate the red and white aesthetic effect of porcelain veneer in the restoration of developmental anterior interdental spaces. METHODS: A total of 152 anterior teeth in 64 patients with developmental anterior dental gaps were restored using porcelain veneers, the aesthetic effects before and after restoration were evaluated by pink aesthetic index (PES) and white aesthetic index(WES), the aesthetic effect of gingival papilla filling and reconstruction was evaluated by interdental gingival papilla index (PIS), and visual analogue score (VAS) was used to compare the satisfaction of patients before and after restoration. SPSS 203.0 software package was used for statistical analysis. RESULTS: The overall mean scores of PES before and after restoration of 152 developmental anterior interdental teeth were 9.63±2.23 and 13.64±0.88, respectively. The average scores of WES before and after restoration were 6.85±1.87 and 9.81±0.58, respectively. There were significant differences of PES and WES scores before and after restoration(P＜0.01). According to the requirements of "near" perfect restoration(PES≥13 points, WES≥9 points), the red and white aesthetic effect after restoration was near the standard. The scores of PIS before and after restoration were 1.86±0.67 and 2.97±0.18, the interdental gingival papilla was completely filled with space, and the shape was ideal, there were significant statistical differences before and after restoration(P＜0.01). Patients were more satisfied with the smile curve and morphology of the restored anterior teeth than other parameters. CONCLUSIONS: The aesthetic effect of using porcelain veneers to repair developmental anterior interdental gaps is ideal, among which the filling of the papillae between the teeth can meet the expectations of patients, and the aesthetic effect evaluation of PIS and PES/WES applied to porcelain veneers to repair developmental anterior interdental spaces has practical guiding significance in clinical practice.