Journal of Esthetic and Restorative Dentistry最新文献

Objective: To investigate the color stability of a one-shade resin-based composite material (RC) and a glass-ionomer cement (GIC) after staining with plaque detectors (PDs) with different formulations and delivery forms.

Materials and methods: Rectangular-shaped specimens (7 × 3 × 2 mm) were produced with RC (Venus Diamond One, Kulzer) and GIC (Fujy IX GP, GC) (n = 30). Further, the following PDs were used on the specimens: (1) tablets (T; Plaq-Search, TePe); (2) mouthwash (M; Plaque Agent, Miradent); and (3) light-curing liquid (L; Plaque test, Ivoclar). The PDs were removed with dedicated toothbrushes (T₁) and the specimens were repolished (T₂). The protocol was repeated after 1 week of storage in artificial saliva (staining-T₃ and repolishing-T₄). Color measurement were performed at baseline (T₀) and all testing times (T₁-T₄) using a recently introduced digital colorimeter (SmartColor, Smart Vision). Color changes (ΔE_ab) compared to T₀ were automatically recorded by the digital instrument. The data were statistically analyzed (p < 0.05).

Results: The type of PD, the polishing procedure and their interactions influenced the color stability of both restorative materials (p < 0.05). Particularly, after the second PDs application, M and L produced the highest color changes (p < 0.05), with GIC showing higher color variability than RC. Although repolishing reduced the color changes of RC (p < 0.05), it could not reestablish the initial color of GIC, irrespective of the PD used (p < 0.05). Except for RC associated with T, all materials exhibited discoloration above the clinical perceptibility (1.77) and acceptability (2.66) thresholds.

Conclusions: The influence of PDs on the color stability of RC and GIC was material-dependent. GIC showed higher color instability than RC. Repolishing could not reestablish the original color of GIC and only attenuated the color changes of the one-shade RC. The newly introduced digital colorimeter was an important tool to standardize and simplify color measurement evaluations.

Clinical significance: PDs can pose a potential risk to the color stability of restorative materials. Dental practitioners should be careful when recommending the frequency of at-home application of PDs, taking into consideration the material properties and the position of the restorations of each patient.

Objective: Minimally invasive dentistry is being widely practiced. The center stone is to be as conservative as possible to minimize unnecessary removal of healthy tooth structure. In prosthodontics the patients have generalized and combined nature of diseases. This narrative literature review analyzed available evidence on minimally invasive treatment protocols in fixed prosthodontics and raised awareness on the importance of longevity of treatments and secondary prevention.

Overview: The long-term clinical survival of ceramic and resin composite materials was reviewed. Loss of tooth vitality after prosthodontic treatment was also explored. And finally, treatment options for patients with severe wear were examined. The search of the literature resulted in evidence of superior survival of ceramic restorations over resin composites. The literature is also clear that ceramic partial coverage inlay and onlay restorations have excellent long-term clinical performance in posterior dentition. Glass ceramic lithium disilicate showed to be an adequate material not only for anterior but also for posterior dentition, including the patients with severe wear.

Conclusions: Minimally invasive dentistry as applied in fixed prosthodontics needs updates in its concepts to account for secondary prevention and longevity of chosen treatment techniques.

Clinical significance: This narrative review article critically reviews available evidence on long-term clinical performance of minimally invasive and traditional treatment concepts and materials in fixed prosthodontics. Awareness is raised for secondary prevention and longevity of chosen treatments.

Purpose: This article presents a different approach to injectable techniques. This technique uses conventional viscosity materials to achieve maximum strength and esthetics.

Clinical considerations: The use of high-viscosity material which has the strongest physical properties is desirable since failure of anterior resin composite has been described as fracture and recurrent decay. By incorporating changes to the conventional injection technique, heating and making bigger access wholes on the matrix allows the utilization of higher conventional viscosity materials.

Conclusions: The use of higher viscosity materials while using injectable techniques is possible by heating and providing a bigger access entrance to composite resin compules.

Objectives: The different scanning errors that can be caused by the operator handling an intraoral scanner (IOS) or the intraoral conditions of the patient being scanned have not been described. The purpose of this review was to describe and classify the scanning errors that can be identified in digital scans recorded by using IOSs.

Overview: The identification of scanning errors in an intraoral scan and understanding the cause of these scanning errors are fundamental procedures for successfully handling an IOS and integrating these digital data acquisition technologies in dental practices. There are two main types of scanning errors: the ones created by the operator and the ones caused by the intraoral conditions of the patient. There are seven operator-related scanning errors: mesh hole, stitching, tissue, reliability, umbrella, implant scan body geometry, and scanning noise errors. Additionally, there are four patient-related scanning errors: humidity, bridge, fuzzy finish line, and scanability noise errors.

Conclusions: The identification of scanning errors is fundamental for assessing the quality of an intraoral digital scan. The comprehensive reading of these scanning errors allows the dental professional to understand if the scanning error can be corrected or if it is related to hardware/software limitations of IOSs.

Objective: To investigate the effect of cervical margin relocation with four different injectable restorative materials on the fracture resistance of molars receiving mesio-occluso-distal CAD/CAM nanoceramic onlay restorations.

Materials and methods: One hundred and five sound mandibular molars received a standardized mesio-occluso-distal onlay preparation, with cervical margins located 2 mm apical to the cemento-enamel junction. The molars were randomly allocated into five groups (n = 21) according to the cervical relocating materials used: Group I had no cervical margin relocation; Group II used a highly viscous glass ionomer; Group III used a highly-filled injectable resin composite; Group IV used a resin-modified glass ionomer; and Group V used a bioactive ionic resin. All groups received immediate dentin sealing before nanoceramic resin-based CAD/CAM onlay restorations. After the specimens were subjected to thermo-mechanical loading, they underwent fracture resistance testing and failure mode analysis.

Results: No statistically significant difference in fracture resistance was observed among the tested groups. Regarding the mode of failure, irreparable failure was significantly dominant, with no significant difference among the groups.

Conclusion: Employing injectable restorative materials for cervical margin relocation had no detrimental effect on the fracture resistance of molars receiving nanoceramic resin-based CAD/CAM onlay restorations.

Clinical significance: CAD/CAM onlay restorations preceded by cervical margin relocation using injectable restorative materials could tolerate compressive loading comparably to those without cervical margin relocation.

Objective: This in vitro study aims to evaluate the effect of placing polyethylene fibers used in large Class II MOD (mesio-occlusion-distal) cavities into different flowable resin composites and in different positions on the fracture resistance of the restoration.

Materials and methods: Ninety healthy human molars were used in the study. No treatment was performed on 10 of these teeth and they were used as the control group. The other 80 teeth were divided into 8 groups by opening large MOD cavities (n = 10). The groups were divided into 4 main groups according to the use of fiber strips; no fiber, placed in the buccolingual direction, placed in the mesiodistal direction, and placed in an "O" shape on all walls. Each main group was divided into two subgroups according to the use of the nanofill flowable composite or flowable short fiber resin composite (SFRC) as the base material. All teeth were aged with a thermal cycler and then fractured with a universal testing machine. Fracture types were recorded in terms of fracture strength and repairability. Kruskal-Wallis, one-way ANOVA, and Tukey post hoc tests were used to compare fracture strength values (p < 0.05).

Results: The highest fracture resistance was observed in the control group (2888.67 ± 395.43 N). The control group was significantly higher than all groups except the 7th and 8th groups (p < 0.05). Among the restored groups, the highest mean fracture resistance values were observed in the 8th group (2463.92 ± 332.37 N). The 8th group was statistically significantly higher than the 1st and 2nd groups (p < 0.05). There was no statistically significant difference between any of the other restored groups (p > 0.05).

Conclusions: The application of polyethylene fiber in the treatment of teeth with large MOD cavities in different positions did not result in a significant difference in fracture resistance.

Objective: To evaluate the influence of in situ acid erosion on the structural and optical properties of nanoparticulate bisacrylic resin with different surface treatments, evaluating surface roughness (Ra), knoop microhardness (KHN), color change (ΔE, ΔL, ΔC, ΔH), contrast (CR) and translucency (TP).

Methods: Eighty specimens were made (n = 10 per group) and the following surface treatments were applied: U_P-unpolished; A_p-polishing with Astropol rubber tips (Ivoclar); S_B-Biscover LV surface sealant (Bisco) and S_P-Palaseal surface sealant (kulzer). For the in situ experiment, 10 volunteers wore an intraoral appliance containing eight specimens (two specimens per experimental group), with only one specimen from each experimental group being subjected to the acid process. They were immersed in 150 mL of cola-based soda (pH = 2.3), 4 × 5 min/day for 14 consecutive days evaluating surface roughness (Ra), knoop microhardness (KHN), color change by CIEDE2000 (ΔE, ΔL, ΔC, ΔH), contrast (CR) and translucency (TP).

Results: The S_B and S_P groups adopted the lowest Ra values, with a significant difference from the others. The S_B group had the highest values of KHN and NP the lowest, with a significant difference from the others. The S_P group had the highest values of ΔE00, being the only one with a significant difference from the others. In all analyses, there was no significant change between the groups without and with acid administration.

Conclusion: The surface sealants were able to improve the surface roughness and microhardness of the bisacrylic resin, however, the Palaseal sealant generates unacceptable color change. The acid injection did not significantly influence the properties of the material, regardless of the surface treatment performed.

Purpose: To compare the color alteration, surface roughness and microhardness and cross-sectional microhardness of bovine enamel treated with at-home whitening strips and gels.

Materials and methods: Sixty-six pigmented specimens (n = 11) were allocated to six groups: C-cotton wool moistened with distilled water for 1 h; SDS-sodium dithionite strip, for 1 h; HPS-6.5% hydrogen peroxide strip, for 1 h; CPS-20% carbamide peroxide strip, for 1 h; HPG-7.5% hydrogen peroxide gel, for 1 h; CPG-10% carbamide peroxide gel, for 4 h. The treatments lasted 10 days, calculating the ∆E, ∆E₀₀, and ∆W_ID at baseline, 5 and 10 days, and 14 days after completion. Additional 66 polished discs (n = 11) were used to analyze the surface roughness and microhardness of enamel before and after bleaching, cross-sectional microhardness and integrated mineral loss (ΔZ; %Vol × μm). Data were subjected to statistical analysis by two-way Anova RM and Tukey post-test (α = 0.05).

Results: In ∆E and ∆W_ID analysis, greater values were obtained in CPG (p < 0.001), followed by HPG and HPS (p = 0.271). SDS and CPS (p < 0.001) exceeded only C (p < 0.001). In ∆E₀₀, at completion of treatments, the results were similar; however, HPG = HPS = CPS (p = 0.237). There was an increase in roughness and decrease in surface microhardness in all bleaching groups (p < 0.005). Concerning the cross-sectional microhardness, the treatments were equal to C at 150 μm, the last depth analyzed. For ΔZ, the values of SDS, CPS, HPG, and CPG groups showed similar mineral loss (p > 0.001), and the lowest value was exhibited in the Control group, followed by HPS group (p < 0.001).

Conclusion: Although the strips were aesthetically effective, the CPG and HPG groups presented highest values in the ∆E₀₀ and ∆W_ID analysis. However, all treatments influenced the enamel surface, increasing roughness and decreasing surface and transverse microhardness.

Clinical relevance: The whitening gels promoted greater chromatic changes, but all treatments affected the enamel surface, increasing roughness and decreasing surface and transverse microhardness.

Objective: This study aimed to evaluate the efficacy and safety of a digitally guided dual technique during esthetic crown lengthening surgery. In addition, patient satisfaction and patient-reported outcomes were assessed.

Materials and methods: A prospective case series study was conducted. Cone-beam computed tomography and intraoral scans were used to design surgical guides, which were manufactured via 3D printing. The primary outcome was surgical accuracy, assessed by measuring the distance between the planned and final gingival margin positions using overlapping intraoral scans. Secondary outcomes included clinical crown length, gingival margin stability, pain, and patient satisfaction. Statistical analyses were performed using multilevel linear regression models, with significance set at p < 0.05.

Results: Ten participants (87 teeth) were treated without complications. The mean duration of surgery was 66.5 min. The overall absolute deviation was 0.56 mm (95% CI: 0.48 to 0.65) at 6 months postoperatively. Clinical crown length increased significantly from baseline to the end of surgery (p < 0.001), with minimal reduction at 6 months (p = 0.479). Patient-reported outcomes indicated mild postoperative pain and high satisfaction with esthetic results.

Conclusions: The digitally guided dual technique for esthetic crown lengthening surgery is safe and effective, providing highly accurate outcomes. The technique also results in excellent patient satisfaction.

Clinical significance: The use of digitally guided dual techniques for ACL surgery enhances precision and safety, leading to highly accurate outcomes and improved patient satisfaction. This approach could be beneficial in clinical settings to ensure better esthetic and functional results.

Objective: This study aims to evaluate extrinsic tooth stain removal and whitening efficacy of two experimental dentifrices containing (i) 5% sodium tripolyphosphate (STP)/1% micronized alumina or (ii) 5% STP/1% micronized alumina with abrasive silica (ED2) compared to a regular fluoride dentifrice (RFD) following 8 weeks of use.

Materials and methods: This was a single-center, randomized, controlled, blind, three-arm, stratified, parallel-group study. Eligible participants underwent clinical assessment of stain on the facial/lingual surfaces of maxillary and mandibular teeth using the modified Lobene stain index (MLSI), and shade of the facial surfaces of the central and lateral maxillary incisors using the VITA Bleachedguide 3D-Master (VITA) shade guide. Participants brushed twice daily with their assigned dentifrice and returned to the clinic for clinical assessments at weeks 4 and 8.

Results: A total of 272 participants completed the study (281 screened, 279 randomized). Both experimental dentifrices demonstrated statistically significant reduction from baseline and significant differences compared to RFD for MLSI and VITA shade scores at 4 and 8 weeks. 10 treatment-related treatment-emergent adverse events were reported in seven participants. All were resolved at the end of the study.

Conclusions: This study demonstrated that dentifrices containing 5% STP/1% micronized alumina provide enhanced stain removal and shade improvements compared to a regular dentifrice. Study treatments were generally well tolerated.

Clinical significance: A low-abrasion daily-use fluoride dentifrice containing 1% micronized alumina and 5% STP, suitable for people at risk of erosive toothwear and/or dentin hypersensitivity, can provide clinically meaningful superior reductions in tooth stain, which translates into a visibly noticeable improvement in tooth shade.