Feldspathic Ceramic Veneers Research Articles

Ultrathin Feldspathic Ceramic Veneers: A Pilot SEM Evaluation of Etched Intaglio Surfaces.

Ultrathin ceramic veneers are a viable therapeutic option to manage esthetic challenges in the anterior zone. Proper conditioning of the intaglio surface of porcelain veneers is essential to achieve an adequate bonding. In clinical practice, this is typically done with chemical etching using an acid-containing agent, such as hydrofluoric acid. While it is well established that the etching effect is dependent on etching time and the acid concentration, little is known about the impact of etching time and the veneer fabrication method. The purpose of this pilot study was to evaluate, using scanning electron microscopy (SEM), the effect that different etching-time protocols have on the intaglio surface characteristics of ultrathin ceramic veneers fabricated with either the platinum foil technique or the refractory die technique. Several replicas of an ultrathin feldspathic ceramic veneer for a maxillary central incisor were fabricated. Individual specimens were processed according to different intaglio surface-etching protocols: no etching, etching for 90 seconds, etching for 120 seconds, and etching for 150 seconds (9.6% hydrofluoric acid used for all etching groups). It was observed that the 120-second etching protocol resulted in a favorable microroughness surface pattern in the platinum foil group. This pattern was comparable to that obtained by etching for 90 seconds with hydrofluoric acid the intaglio surface of veneers fabricated with the refractory die technique. Increasing the etching time to 150 seconds did not result in a more favorable roughness pattern.

Retrospective Long-Term Clinical Outcome of Feldspathic Ceramic Veneers.

The purpose of this study was to evaluate the clinical outcome of feldspathic ceramic laminate veneers over a 7-year period using minimally invasive techniques, such as vertical preparation (without prosthetic finish line), or no preparation (no-prep). A total of 170 feldspathic ceramic veneers were cemented in the anterior region, including 70 maxillary and 100 mandibular veneers, after special conditioning of the teeth and restorations. The veneers were evaluated using the FDI World Dental Federation criteria evaluation kit after recalling all the patients between February and June 2021. In total, 14 feldspathic veneers failed and were replaced with lithium disilicate because of core fracture, and 10 cases of chipping occurred on the ceramic surface and were polished. The overall survival rate was 91.77% for up to 7 years of function, with a failure rate of 8.23%. In this retrospective survival analysis, the failures, including the fracture of veneers and dental hard tissue, occurred both in prep and no-prep teeth. No failures were observed in veneers with a maximum thickness of 0.5 mm compared to those with a maximum thickness of 1 mm, 1.5 mm, 2 mm, and 2.5 mm.

Comparison of feldspathic veneer surface treatments on ceramic bracket SBS, ARI and surface roughness after different debonding/polishing methods: An in vitro study

To analyse, in vitro, surface properties and the shear bond strength after debonding and polishing procedures of ceramic brackets directly bonded to 0.3-0.5-mm thick feldspathic veneers. Fifty six feldspathic ceramic veneers samples (0.3 to 0.5-mm thick) were allocated into groups according to veneers surface treatment procedures: (S) glaze layer was retained; (SHF) hydrofluoric (HF) acid etch; (SOXA) Al2O3 sandblasting; and (SB) diamond burs roughening. Specimens were treated with silane Monobond N® and ceramic brackets bonded with Transbond XT®. Shear bonding strength (SBS) was assessed with a universal testing machine and ARI evaluated under a stereomicroscopic coupled to a digital camera. Remaining bonding composite was removed using a porcelain polishing kit and surface roughness assessed with a stylus profilometer. No statistically significant differences were identified for SBS among the study groups (S, SHF, SOXA and SB) (P>0.05). The majority of the specimens presented ARI scores 3 and 2 (P>0.05). All of the study groups presented increased surface roughness after debonding and polishing procedures (P<0.05), with significant greater values observed in SB group (RaF: 1.27±0.41; RzF: 6.23±1.82), (P<0.05). Surface treatment with hydrofluoric acid etch, Al2O3 sandblasting and diamond bur did not enhance SBS of orthodontic brackets bonded to ceramic veneers. Ceramic surfaces treated with diamond burs presented significantly increased roughness after adhesive removal.

Er,Cr:YSGG Laser in the Debonding of Feldspathic Porcelain Veneers: An In Vitro Study of Two Different Fluences.

Background: New applications in laser technology in aesthetic restorative dentistry merit further research. This study compares the debonding strength and failure mode of feldspathic ceramic veneers using either Er,Cr:YSGG (erbium,chromium:ytrrium-scandium-gallium-garnet) laser at two levels of fluency or no laser (control group). Methods: An in vitro comparative study was carried out using bovine teeth that were randomly distributed into 3 groups of 21 specimens each: (a) experimental group 1 (EG1): irradiated with Er,Cr:YSGG (Waterlase iPlus®; Biolase, Irvine) at an energy density per pulse of 4 J/cm2, using a handpiece (Turbo; Biolase) with a sapphire tip (MX7) and applying the beam perpendicular to the specimen at a distance of 4 mm for 60 sec; (b) experimental group 2 (EG2): irradiated as in EG1, but at 2.7 J/cm2; and (c) control group (CG): debonding without laser irradiation. Results: The stress required for veneer debonding was 8.19 MPa in CG, 0.91 MPa in EG1, and 0.48 MPa in EG2. The difference between the control and both experimental groups was statistically significant (p < 0.001). The percentages of adhesive failure were 40%, 61.9%, and 96%, respectively. Conclusions: Using the Er,Cr:YSGG laser at 4 or 2.7 J/cm2 requires significantly less force to debond ceramic veneers. The percentage of adhesive failures in the two experimental protocols was higher than in the control group. Application of the Er,Cr:YSGG laser using the parameters in this study may be useful in removing feldspathic ceramic veneers, avoiding damaging them and protecting the enamel.

An 8-year prospective clinical investigation on the survival rate of feldspathic veneers: Influence of occlusal splint in patients with bruxism

ObjectivesThe aim of this study was to perform a 8-year prospective clinical investigation on the survival rate of feldspathic ceramic veneers, as well as analyse the influence of the occlusal splint in patients with parafunctional bruxism. MethodsThree hundred and sixty-four veneers fabricated using conventional feldspathic ceramic were provided in 64 patients. The patient sample included 40 individuals with bruxism. During the follow-up period, the effect of wearing the occlusal splint on the incidence of failure (fracture and/or debonding) in patients with bruxism was also assessed. The survival rate of veneers was determined using the Kaplan-Meier estimator. Statistical significance was set at p < 0.05 with a confidence interval of 95%. ResultsThe occurrence of fracture for the feldspathic veneers tested in this study was 7.7%, while only 1.9% of the total number of veneers debonded. The overall survival rate was 93.7% after 3 years, 91% after 5 years, and 87.1% after 8 years. Patients with bruxism using an occlusal splint showed a survival rate of 89.1% after 7 years, while the survival rate in patients with bruxism using no occlusal splint was 63.9% (p < 0.05). ConclusionThis study confirmed that feldspathic veneers may represent a suitable clinical solution for indirect aesthetic restorations. Such a treatment may be an option also for those patients affected by bruxism, as long as they regularly wear an occlusal splint. However, patients with bruxism using no occlusal splint may still present a potential high-risk of failure and/or debonding.

Color stability of ceramic veneers as a function of resin cement curing mode and shade: 3-year follow-up.

The influence of curing mode and shade of resin cements on the color stability of minimum-thickness ceramic veneers after a three-year storage time in distilled water was evaluated in this study. Ninety-six 0.5-mm-thick feldspathic ceramic veneers (Mark II) were luted onto resin composite substrates (Filtek Z350 XT, shade A2E) with two light-cured (NX3 Light-cure and AllCem Veneer) and dual-cured resin cements (NX3 dual-cure and AllCem) in various shades. The specimens were stored in distilled water at 37°C. Color measurements were performed with a spectrophotometer at the following times: 1h and 24h; 7, 30, and 180 days; and 1, 2, and 3 years. Data for color difference (ΔEab) light-cured and dual-cured resin cements were analyzed by two-way ANOVA with repeated measures and Tukey’s test (α = 0.05). For the light-cured cements, the ΔEab values were as follows: NX3-Yellow (2.37±1.35) = ACV-A1 (2.40±1.21) = ACV-Trans (2.52±1.46) = ACV-E-Bleach M (2.56±1.42) = NX3-White (2.69±1.49) = NX3-Clear (2.98±1.68). The lowest ΔE values were found for 1 h (0.61±0.36)a, followed by 24 h (1.15±0.55)b and 30 days (2.48±1.11)c. One year, 180 days, and 2 and 3 years presented higher ΔEab values (3.34±0.94, 3.52±1.04, 3.52±0.95 and 3.55±1.14, respectively)d. For the dual-cured cements, the ΔEab values varied as follows: NX3-Clear (2.32±1.24)a = NX3-Yellow (2.37±1.32)a = NX3-White (2.76±1.43)a < AC-Trans (3.77±1.91)b = AC-A3 (4.13±2.11)b < AC-A1 (5.38±2.92)c. Considering time, the lowest ΔEab values were found for 1 h (0.48±0.25)a, followed by 24 h (2.13 ±0.83)b, 30 days (3.54±1.31)c, and 180 days (3,70±1.73)c. The follow-up times of 1 (4.43±2.15)d, 2 (5.02±1.74)e, and 3 years (4.90±2.12)e presented higher ΔEab values. This study demonstrated that light-cured resin cements were less susceptible to color change than dual-cured cements. After 2 years of follow-up, all cements presented ΔEab values above the acceptability threshold.

Outcome of posterior fixed dental prostheses made from veneered zirconia over an observation period of up to 13 years

ObjectivesIt was the aim of this clinical study to evaluate the long-term outcome of 3- to 4-unit posterior all-ceramic fixed dental prostheses (FDPs) made from veneered zirconia ceramic. MethodsBetween June 2003 and February 2005, 48 patients received 58 restorations. Twenty-four FDPs had a fixed-to-fixed design (FF) and thirty-four FDPs had a cantilever design (CA). Frameworks were scanned and milled out of 3 mol% yttrium-oxide partially-stabilized zirconia ceramic (CerconBase30, Degudent) and were veneered with feldspathic ceramic (CerconCeramS, Degudent). All FDPs were cemented with glass-ionomer cement (Ketac-Cem, 3 MEspe) after air-abrading the inner crown surfaces. ResultsThe mean observation period was 85.4 ± 54 (FF) and 91.7 ± 50 (CA) months, respectively. Ten cantilever FDPs and 5 fixed FDPs were lost due to biological problems of the abutment teeth. Two cantilever FDPs and 4 fixed-to-fixed FDPs were lost due to technical failures of the ceramic materials. The cumulative 13-year survival rate was 43.2% (FF) (CI: 22.8–66.2%) and 52.5% (CA) (CI: 32.5–71.8), respectively. In 13 cases, intraoral repair or polishing of the fractured feldspathic ceramic veneers was needed (7 in group FF, 6 in CA). Eight abutments of six restorations (4 in FF, 4 in CA) had to be treated endodontically and caries therapy was needed in 6 abutment teeth (4 in group FF, 2 in CA). The cumulative 13-year success rate was 29.5% (FF) (CI: 12.1–55.9%) and 22.5% (CA) (CI: 7.9–49.3%). ConclusionsWithin the limitations of the present investigation, posterior fixed dental prostheses made from veneered zirconia with either a fixed-to fixed or a cantilever design show comparable survival and success rates after 13 years of clinical observation. Clinical SignificanceFDPs made from veneered zirconia ceramic present high failure and complication rates, irrespective of the design (fixed-to-fixed or cantilevered).

Rata de supravieţuire a faţetelor feldspatice versus cea a faţetelor presate

Rata de supravieţuire a faţetelor feldspatice versus cea a faţetelor presate

Esthetic rehabilitation with minimally invasive feldspathic ceramic veneers: 30 months of clinical follow-up

Diastemas among maxillary incisors and gingival contour disharmony are common findings among patients in dental practice. Ceramic veneers are indicated for esthetic rehabilitation of anterior diastemas due their predictable results, optical characteristics, fracture resistance and tooth structure conservation. However, because it is a friable material and have a brittle behavior, fractures occurrences are related to trauma, oclusal overload, parafunctional habits and material fatigue. This article describes 30 months follow-up of an esthetic and functional rehabilitation diastemas closure using feldspathic veneers associated with periodontal surgery and a ceramic repair with composite resin. Gingivectomy and frenectomy needs were found and the surgical procedures performed guided by new anatomic aspects of the crowns. Mock-up was performed after waxing and reverse planning. All anterior teeth underwent minimally invasive preparation. Feldspathic ceramic veneers were made, tried using try in paste and luted with light-cure resin cement. After 24 months, a fracture occurred on the right maxillary canine veneer. The ceramic restoration repair was performed with nano-hybrid composite resin, after the conditioning with 5% hydrofluoric acid, 37% phosphoric acid and silane couple agent. The combination between ceramic veneers and gingivectomy enables to obtain conservative treatments and esthetic success. After six months of the repair, resulting 30 months of follow-up, the anterior restorations were aesthetically and functionally satisfactory.