Journal of Esthetic and Restorative Dentistry最新文献

Background: The demand for discreet and low-compliance appliances has driven innovation in orthodontics, particularly with technological advances in artificial intelligence, robotics, and CAD/CAM technology. The evolution of Programmed Non-Sliding Mechanics for precise, automated tooth movement is the latest innovation.

Aim: In this article, we aimed to demonstrate the application of a novel orthodontic lingual appliance, The Gen 2 InBrace system (InBrace, Irvine, CA), in the orthodontic-restorative treatment of an adult patient with anterior tooth-size discrepancies, anterior openbite, and incisor proclination. The Gen 2 InBrace system uses a new generation of CAD/CAM Smartwires, including pre-programmed customized multiloop nickel-titanium lingual archwires, which enable light, continuous, and frictionless tooth movements.

Conclusion: The Gen 2 InBrace system can enhance esthetic and occlusal outcomes in patients requiring combined orthodontic-restorative treatment via automatic space management with maximum esthetic and minimal compliance.

Clinical significance: Precision dentistry and orthodontics using esthetic custom appliances have become a reality. The Gen 2 InBrace system, a new generation custom lingual appliance, offers effective treatment solutions for adults who have previously avoided preprosthetic orthodontics due to the esthetic concerns of wearing traditional labial braces or the compliance challenges associated with clear aligners.

Objective: The purpose of this in vitro study was to assess and compare the accuracy of three digital impression techniques based on an innovative integrated model.

Materials and methods: The integrated model was created by incorporating crown, inlay, and long-distance specimens from the American Dental Association (ADA) Standard No. 132. Digitized files of the model were acquired using three distinct impression techniques: intraoral scanner (IOS), extraoral scanner with negative cast (EOS_N), and extraoral scanner with positive cast (EOS_P). A coordinate measuring machine (CMM) was employed to establish the gold standard. The digital files of the model obtained via the extraoral scanner were designated the reference set for 3D fitting. Statistical analysis was performed using a one-way analysis of variance and Tukey's posthoc test.

Results: For the crown specimen, the relative error of EOS_N for indices d₁ and d₂ was higher than that of IOS and EOS_P. For the inlay specimen, IOS showed the highest trueness for d₃ and h₂. For the long-distance specimen, IOS exhibited superior trueness for indices l₁ and l₃. EOS_N displayed the lowest trueness for l₂. For l₄, IOS had the largest relative error. No significant differences were observed among the three groups for l₅ and l₆. Notable deviations were evident in the 3D fitting maps at various locations in three experimental groups.

Conclusions: The three digital impression techniques exhibited varying capacities for capturing features of the integrated ADA model. For crown preparations, IOS and EOS_P are recommended, while for inlay preparations, no technology meets the standard requirements. IOS is recommended for partial impressions, while both EOS_N and EOS_P are suited for full-arch impressions.

Objectives: The modern approach to managing noncavitated white spot lesions (WSLs) emphasizes noninvasive strategies and biomimetic remineralization. Biomimetic scaffolds are designed to regenerate dental tissues rather than simply repair them. This study aimed to assess lesion depth, enamel structure, and the elemental composition of artificially induced WSLs after treatment with biomimetic remineralization techniques.

Materials and methods: Ninety-six freshly extracted anterior teeth, free from caries or enamel defects and extracted due to periodontal disease, were used. White spot lesions were induced on the labial surfaces, and the samples were divided into three groups based on the remineralizing agent: Group I, treated with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), which served as the positive control; Group II, treated with self-assembling peptide P11-4 (SAP-P11-4); and Group III, treated with phosphorylated nano-chitosan (Pchi-ACP). Enamel topography was analyzed at baseline and after treatment using polarized light microscopy, micro-Raman spectroscopy, and scanning electron microscopy. Statistical analysis was conducted using one-way ANOVA, Kruskal-Wallis, and Dunn's post hoc test (p = 0.05).

Results: The Kruskal-Wallis test indicated a significant difference in remineralization potential among the groups. Pchi-ACP showed the greatest reduction in lesion depth (62.65%), demonstrating significant subsurface enamel remineralization. This group also exhibited a smooth, regular enamel surface with shallow linear depressions. Elemental analysis confirmed successful calcium phosphate precipitation in Pchi-ACP, indicating a trend toward enamel regeneration.

Conclusion: Pchi-ACP represents a promising biomimetic and minimally invasive approach for treating early WSLs, signifying a transition toward regenerative dentistry. (SAP-P11-4), while effective, was less successful than phosphorylated nano-chitosan but outperformed (CPP-ACP).

Clinical significance: Pchi-ACP demonstrates significant potential for minimally invasive treatment of early noncavitated carious lesions. By preserving natural tooth structure, this approach could greatly enhance oral health outcomes in the long term.

Objective: The aim of this in vitro study was to evaluate the accuracy of resin-based fixed dental restorations, namely veneers, single crowns, and four-unit fixed partial dental prosthesis (FPDs), using two different 3D printing technologies and polymer-based materials.

Materials and methods: A standard maxillary polyurethane jaw model containing prepared teeth was scanned using an intraoral scanner. The generated STL data were used to design the restorations virtually using CAD software. Two 3D printers were utilized for the provisional digital light processing and stereolithography for the castable resin patterns. Each printer produced 10 specimens of each type of restoration, for a total of 80 restorations. The 3D-printed restorations were then 3D scanned using the same intraoral scanner and evaluated for external and internal dimensional accuracy in terms of trueness and precision. A one-way ANOVA and two-sample T-test were implemented to compute the precision (variability between groups) and trueness (with the designed CAD model). A level of statistical significance of p-value < 0.05 was set.

Results: Statistical differences in the external dimensional analysis of the incisors, molars, and four-unit FPD with p-values < 0.001, 0.002, and 0.004, respectively. For the internal dimensional analysis, the overall mean values of trueness ranged between 17 and 52 μm, and the variability was significant.

Conclusion: The external and internal dimensional accuracy values of the 3D-printed fixed dental restorations in this in vitro study in terms of trueness can be clinically accepted after chairside modifications. However, significant variability between the 3D-printed restorations was observed. Further investigations are needed to improve the accuracy of the 3D-printed fixed dental restorations.

Clinical significance: In terms of clinical applications, 3D-printed fixed dental restorations produced by both 3D-printing technologies and polymer-based materials achieved acceptable levels of trueness, although some variability was observed. Significant deviations from the CAD model may require further chairside adjustments. Future integration of AI with 3D-printing may further improve the accuracy and efficiency of fixed dental restoration production.

Objective: To provide guidelines and means for optimal coverage and distribution of computer models with 1-10 clusters, designed based on an in vivo extensive dental colorimetric database and compare the findings with some reputable shade guides.

Materials and methods: The Fuzzy C-Means (FCM) algorithm was used to optimize the tab position in the CIELAB color space, while MATLAB Fuzzy Logic was used to implement the codes. A minimization process was performed to fine-tune the cluster centers, minimizing Coverage Error (CE₀₀) and Maximum Error (ME₀₀). Spectral reconstruction was performed, and the results were compared with the corresponding data for VITA classical A1-D4 (VC), Linearguide 3D-Master (LG), and Bleachedguide 3D-Master (BG) shade guide. Paired t-test was employed to assess the significance of CE₀₀ differences.

Results: CE₀₀ and ME₀₀ ranges for 1-to-10-tab models were 3.8 (14.2) to 1.7 (4.3), while the corresponding values for shade guides were 3.1 (9.1) for VC, 2.3 (6.0) for LG, and 2.9 (9.3) for BG. Hence, the 4-tab-model with CE₀₀ of 2.2 and ME₀₀ of 7.1, outperformed CE₀₀ of LG (the lowest/best CE₀₀ among shade guides), while the 6-tab-model, with CE₀₀ of 2.0 and ME₀₀ of 5.6, outperformed its ME₀₀. A paired t-test confirmed that increasing the number of tabs models resulted in significant CE improvement in all cases (p ≤ 0.05).

Conclusions: Shade guide models with only 4 to 6 tabs, optimized using computational techniques, outperformed physical dental shade guides tested, exhibiting significantly lower (better) Coverage Error and Maximum Error.

Clinical significance: Given that the spectral modeling was performed on an extensive in vivo database of natural teeth, this approach was validated as a biomimetic guide for shade guides and corresponding materials of the future, offering a possibility for better shade matching with fewer shades/shade tabs.

Objectives: This study aimed to evaluate the clinical performance of ceramic veneers after 9-10 years, assess patient-reported outcomes, and examine their associations.

Materials and methods: Thirty patients with ceramic veneers aged 9-10 years were recalled for a clinical examination. Each participant completed a questionnaire on satisfaction and oral health-related quality of life, specifically using the Oral Impact on Daily Performance (OIDP) scale. The chi-square or Fisher exact test was used to assess the associations between tooth position and professional evaluations of veneer success and individual items. Consistency between professional evaluations of the veneers and patient-reported outcomes was evaluated using Weight Kappa.

Results: A total of 30 patients with 233 veneers participated in the study. Clinical evaluations deemed 9.87% (n = 23) of veneers as successful, 79.40% (n = 185) as surviving with complications, and 10.73% (n = 25) as a failure. The most common complications were marginal adaptation, gingival inflammation, and marginal discoloration. The participants were most frequently dissatisfied with the function of the veneers, food impaction, and cleaning difficulties. The OIDP assessment indicated that problems on daily activities such as cleaning, eating, and sleeping were predominantly affected. There were significant consistencies between certain clinical performance attributes and patient-reported outcomes.

Conclusions: The survival rate of ceramic veneers was 89.3% after 9-10 years of follow-up. Among these, 79.4% had survived with complications such as material defects, secondary caries, and gingival problems. Given the discrepancies between patient-reported outcomes and clinical evaluations, further investigations into patient perception are needed alongside traditional clinical assessments.

Clinical significance: Educating patients about the potential complications associated with veneer restoration, especially specific to tooth location, is essential. Additionally, advising patients on proper oral hygiene practices is recommended to minimize the risk of gingival inflammation to enhance the longevity of the restoration.

Objective: This article presents a clinical case of erosive tooth wear, in which the vertical dimension of occlusion (VDO) has been restored using defect oriented posterior onlays and anterior veneers respecting minimal invasive treatment approaches.

Clinical consideration: A 44-year-old female with the history of bulimia nervosa and bruxism expressed the desire to improve the aesthetic appearance and reestablishment of function of her worn dentition. After a 3-month functional therapy to ease myofunctional problems using a Michigan splint, a diagnostic phase revealed the necessity for a full mouth prosthetic rehabilitation. A slight increase of the VDO of 1 mm at the incisal point was determined. Veneered lithium disilicate ceramic restorations of 0.3-0.5 mm in thickness were produced for the incisors and monolithic lithium disilicate restorations of 0.8-1.0 mm in thickness for posterior teeth.

Conclusions: Functional and aesthetic prosthodontic rehabilitation of severely worn teeth can be achieved satisfactory with minimal invasive procedures using defect oriented, indirect lithium disilicate ceramic restorations with increasing the VDO to its original state.

Clinical significance: Indirect, minimal invasive lithium disilicate ceramic restorations are suitable to restore the VDO of severe dental erosions.

Objective: To explore the influence of abutment selection on 3D implant positioning, emphasizing the synergy between surgical and prosthetic considerations for achieving predictable long-term outcomes in implant-supported restorations.

Main considerations: Implant dentistry has transitioned from a purely surgical approach to a prosthetically driven methodology that prioritizes implant-supported restoration (ISR). This shift has been bolstered by advancements in digital technologies and abutment designs, which allow for more precise implant positioning and better management of biological, mechanical, and esthetic outcomes. The selection of appropriate abutments plays a pivotal role in optimizing the 3D implant position, influencing peri-implant tissue stability and the overall success of the restoration. This manuscript explores into the biorestorative concept, highlighting how virtual planning can preemptively assess abutment configurations and their interactions with surrounding tissues, guiding implant placement to achieve desired results.

Clinical significance: The integration of digital planning and strategic abutment selection prior to implant placement ensures optimal 3D implant positioning respecting fundamental biological and prosthetic parameters. This approach minimizes complications, improves long-term tissue stability, and enhances patient outcomes by aligning surgical procedures with the specific prosthetic needs.

Introduction: Ultratranslucent zirconia combines high mechanical strength and esthetics, making it ideal for monolithic restorations. This case report describes a total rehabilitation of the upper dental arch with single-unit crowns made of multilayer ultratranslucent zirconia (Prettau 4 Anterior, Zirkonzahn), as well as the use of a simplified adhesive cementation protocol for this type of ceramic.

Materials and methods: A 64-year-old female patient sought rehabilitative treatment, after planning in a semi-adjustable articulator, interim prostheses, from tooth 2 to 15, were installed to restore occlusal vertical dimension and esthetics. After all surgical, periodontal, and endodontic procedures, impressions of the upper and lower arches were taken. In the maxilla, 14 zirconia crowns with a color gradient were fabricated and cemented, with their internal surface treated with a multimode adhesive system containing zirconia primer (Single Bond Universal, 3M ESPE). The same adhesive system was applied to the preparations, and the crowns were cemented with dual resin cement (RelyX Ultimate, 3M ESPE).

Results: After the crowns exhibited excellent esthetic results, with only a minor fracture observed on the palatal cusps of the right first upper premolars.

Conclusions: Thus, ultratranslucent zirconia appears to be a viable option for oral rehabilitation with single-unit crowns due to its excellent clinical performance.

Clinical significance: Monolithic ultratranslucent zirconia crowns are able to reproduce the natural characteristics of dental elements. Additionally, the application of 10-methacryloyloxydecyl dihydrogen phosphate-based primer has proven to be an efficient surface treatment for adhesive cementation of UT zirconia.