Operative dentistry最新文献

Adhesive dentistry has undergone significant advancements since its inception, marked by continuous improvements in material performance and adaptability to various dental and restorative substrates. Initially, the anatomical differences between enamel and dentin made adhesive approaches challenging. Early systems were often complex and operator dependent, leading to the development of multistep protocols. However, advancements have led to the creation of more user-friendly self-etch systems and the emergence of universal adhesives (UAs). These UAs can be applied with equal effectiveness to different substrates, including enamel and dentin, simplifying the clinical workflow and enhancing reliability. The concept of universality has recently been extended to other dental materials, most notably universal resin cements. These cements offer a versatile approach as they are capable of both adhesive and self-adhesive bonding, thereby accommodating a wide range of restorative scenarios. The advent of these materials represents a significant advance toward simplifying procedures, reducing technique sensitivity and the likelihood of operator error, and achieving consistently high quality restorations. Current research focuses on further refining these universal materials to enhance their performance, making them a cornerstone of modern adhesive dentistry.

YouTube has emerged as a popular platform for accessing educational content. However, its effectiveness has been a topic of debate in dental education. This study aimed to analyze the content and quality of YouTube videos focusing on Class II resin composite restorations. The first 100 videos of Class II resin composite information on YouTube were evaluated. The overall quality of the videos was assessed using the video information and quality index (VIQI) and Content Score based on Class II resin composite criteria. Videos with a score of less than the mean were recognized as low-content. No significant differences were observed between high- and low-content videos when the number of views, likes, duration, days since upload, viewing rate, and interaction index were investigated (p>0.05). The number of subscribers revealed a marginally significant difference (p=0.053). The high-content videos demonstrated higher mean values compared to the low-content videos in flow (4.6 vs. 3.8; p=0.0004), accuracy (4.3 vs. 3.3; p<0.0001), value (3.7 vs. 2.9; p=0.002), and precision (4.8 vs. 4.2; p=0.0002). The overall VIQI score was significantly higher (p<0.0001) in high-content videos (Mean 17.4; SD 1.5) compared to the low-content videos (Mean 14.2; SD 2.2). When the Content Score was assessed, high-content videos (Mean 9.9; SD 1.3) revealed a higher score (p<0.0001) than low-content-videos (Mean 4.2; SD 2.3). Most YouTube videos showcasing Class II resin composites serve as effective teaching tools. However, a significant number of videos with low content exist. Therefore, dental students should exercise caution when utilizing YouTube videos for learning purposes.

This study evaluated the influence of six resin composite coating agents on color stability and surface roughness after toothbrushing abrasion. Discs (Ø6 mm x 2 mm) of nanofilled resin composite (Filtek Z350XT) were prepared for application of coating agents (n=10): control (absence), two surface sealants (PermaSeal and BisCover LV), two adhesive systems (Scotchbond Multi-Purpose Adhesive/3M Oral Care and Single Bond Universal), and two modeling liquids (Modeling Resin and Composite Wetting Resin). CIELab*, WID, and color change (ΔEab, ΔE00, and ΔWID) were analyzed at baseline, after finishing and polishing, after application of coating agents, after coffee staining (simulating 30 days and one year of staining), and after toothbrushing abrasion. Roughness evaluations (Ra) were performed at the initial time point, after finishing and polishing, after application of coating agents, and after toothbrushing abrasion. Surface micromorphology was evaluated (2,000×) before and after toothbrushing abrasion. Generalized linear mixed models or Kruskal-Wallis and Dunn tests (α=0.05) showed that L* decreased significantly (p<0.0001) and a* increased significantly in all the groups after staining (p<0.0001). After toothbrushing, Modeling Resin showed higher ΔEab and ΔE00 than the control, Scotchbond Multi-Purpose Adhesive, Composite Wetting Resin, PermaSeal, or BisCover LV (p<0.0001). There was a significant increase in roughness for Composite Wetting Resin, Modeling Resin, and PermaSeal after application of the agents (p<0.05), but a significant decrease for BisCover LV (p<0.05), which achieved high surface smoothness. After abrasive wear, BisCover LV showed the lowest roughness values among all agents. Composite Wetting Resin and Modeling Resin showed higher roughness than the other groups (p<0.05), and surface irregularities. In conclusion, the coating agents did not prevent coffee staining, and they also led to increased surface roughness, with only BisCover LV providing greater surface smoothness after toothbrush abrasion.

Objectives: This case report describes the clinical protocols for the removal of crowns, tooth extraction, immediate implant placement, and cementation of new crowns, all performed under total or partial isolation with a dental dam.

Clinical considerations: The patient's chief complaint was dissatisfaction with her smile. Radiographic and clinical evaluations led to the recommendation to replace the porcelain-fused-to-metal crowns on the maxillary central and lateral incisors with all-ceramic crowns. Considering the patient's wide smile, ceramic veneer restorations were also recommended for the maxillary canines and first premolars. An immediate implant placement was advised to replace the fractured maxillary right central incisor.

Conclusions: Well-planned dental care including crown removal, tooth extraction, immediate implant placement, and cementation of new restorations can be successfully executed under isolation using a dental dam. The isolation improves access, visibility, and hygiene by preventing cross-contamination during the cementation procedure. The final outcome fulfilled the patient's esthetic demands.

Objective: The purpose of this study was to compare the optical, mechanical, and biological properties of two new, inexpensive lithium disilicate (LS2) materials (Lodden (LOD), LD Medical Technology; and BeautyZir (BZ), BeautyZir Technology) to a clinically established LS2 material (IPS e.max CAD (EMAX), Ivoclar Vivadent).

Methods and materials: The optical properties of the translucency parameter (TP) and opalescence parameter (OP) were obtained with a dental spectrophotometer. The mechanical properties of flexural strength (FS) and flexural modulus (FM) were determined through a three-point bend test conducted using a universal testing machine. Biocompatibility tests were conducted by analyzing cell proliferation using spectrophotometric absorbance (optical density) to determine relative growth rate and cytotoxicity. Representative specimens of the three LS2 materials were analyzed with X-ray diffraction to determine the relative crystalline phases. Data were analyzed with oneway ANOVA and Tukey's post hoc test (α=0.05).

Results: Significant differences in optical and mechanical properties were found amongst the groups (p<0.05). Both LOD and BZ had significantly greater TP and OP compared to EMAX. EMAX and LOD had greater FS and FM than BZ. No significant differences in optical density or relative growth rate were found among any of the LS2 groups (p>0.05). EMAX and LOD had greater weight percent of lithium disilicate than BZ.

Conclusions: The new lithium disilicate LS2 material, LOD, exhibited better optical properties while maintaining mechanical and biological properties similar to the established LS2 material, EMAX.

Objective: This case report presents a novel technique for bridge restoration using polytetrafluoroethylene (PTFE) tape and split dam isolation in situations where achieving complete dental dam isolation is challenging.

Clinical considerations: Achieving high-quality isolation by controlling gingival crevicular fluid and intraoral relative humidity is important during cementation. However, an improved technique during bridge restoration is needed due to the difficulties faced with dental dam isolation. A porcelain fused to zirconia bridge extending from the maxillary canine to the first molar was used to demonstrate the novel restoration technique in this case report. Split dam isolation lowers the relative humidity in the oral cavity, and PTFE blocks the gingival crevicular fluid. The effects of combining PTFE tape with split dam isolation on isolation (controlling crevicular fluid, saliva, and relative humidity in the operative field) were similar to those obtained with dental dam isolation and made for easier removal of excess cement.

Conclusions: The novel technique introduced in this case report can enhance isolation quality during bridge restoration.

This paper aims to raise a discussion from the perspective of maintaining long-term oral health, posing a critical question: What holds greater significance for maintaining oral health, the longevity of restorations or teeth? This question explores the aspects that truly matter in ensuring sustained oral health throughout an individual's life. Restoration longevity is well-researched, and evidence shows several risk factors influencing longevity. The dentist's decision-making factor may be of utmost importance, and further studies are needed to investigate its relevance. The critical risk factors for restoration longevity are active pathology (high caries risk), less prominent parafunction, and extensive defects such as endodontic treatment. However, tooth longevity and the main risk factors for tooth loss are not well-researched. The evidence shows dental caries, and its sequelae, are the principal reasons for tooth loss. Patient-related risk factors, especially those associated with lifestyle and health choices, play a major role in the longevity of restorations and, more importantly, tooth longevity. To provide personalized dental care with maximum patient benefit, clinicians should identify and record potential risk factors, promoting a healthy lifestyle to ensure tooth and dentition longevity. Moreover, the evidence suggests that decision-making frameworks based on minimal intervention principles offer the best standard for clinical practice, promoting a longstanding healthy oral environment.

This study evaluated the effect of 2.5% sodium hypochlorite (SH) or calcium hypochlorite (CH) submitted to passive ultrasonic irrigation (PUI) or conventional irrigation (CI) on the incidence of residues and the bond strength of the cementation system to post-space dentin. Distilled water (DW) and 2.5% SH followed by 17% EDTA (SH-ED) were used as negative and positive control groups, respectively. The cervical, middle, and apical thirds of the post space were evaluated. One hundred and twenty bovine incisors were endodontically treated and post-space preparation was performed. The specimens were randomly assigned to six groups, according to the solution and irrigation method: DW-CI, SH-ED-CI-SH, SH-CI, SH-PUI, CH-CI, and CH-PUI. The incidence of residues (n=10) over the dentin was evaluated by scores using SEM images. Other specimens were irrigated as previously described and the post cementation was immediately performed using a conventional dual resin cement and a two-step etch-and-rinse adhesive system. Push-out and failure modes were performed for bonding evaluation. Kruskal-Wallis and Dunn test for incidence of residues data and one-way ANOVA and Tukey tests for bond strength data were used at a significance level of 5%. The protocols that showed a lower incidence of residues were: SH-ED-CI-SH, SH-PUI, and CH-PUI for the cervical third and SH-ED-CI-SH for the middle third (p<0.05). In the apical third, the protocols were similar to each other (p>0.05). Bond strength values were higher after irrigation with DW-CI for all thirds (p<0.05). 2.5% sodium or calcium hypochlorite negatively impacted the adhesion interface and exhibited a greater incidence of residues over the post-space radicular dentin.