Implant-supported Restorations Research Articles

Single posterior implant-supported restorations fabricated using a scannable healing abutment versus a conventional scan body: A randomized controlled trial

Statement of problemThe use of a scannable healing abutment is a convenient option for fabricating implant-supported restorations (ISRs) with a digital workflow; however, clinical studies evaluating prosthetic efficacy are lacking. PurposeThe purpose of this randomized controlled trial was to investigate the prosthetic efficacy of definitive posterior single ISRs fabricated after scanning using a scannable healing abutment-scan peg (SHA-SP) in comparison with a conventional scan body (CSB). The time for data acquisition, quality of proximal and occlusal contacts, and relative occlusal force of ISRs were measured. Material and methodsTwenty-four participants eligible for single ISRs to replace the mandibular first molar with adjacent and antagonist teeth present were randomly allocated to either a study group (n=12) receiving ISRs after intraoral scanning using an SHA-SP or a control group (n=12) receiving ISRs after intraoral scanning using CSB. During the surgical procedure, a prefabricated contoured scannable healing abutment was screwed to the implant in the SHA-SP group, while a custom-made healing abutment was used in the CSB group. After a healing period of 3 months, an intraoral scan was made, and the duration of data acquisition was recorded. The ISRs were milled from zirconia and evaluated for the quality of proximal and occlusal contacts using dental floss and shim stock, respectively. The relative occlusal forces of the ISRs and their contralateral natural teeth were measured using a digital occlusal analyzer. Statistical analysis was done using an independent sample t test for quantitative variables and a Pearson chi-squared test for qualitative variables between the tested groups (α=.05). ResultsThe direct digital workflow using SHA-SP was statistically less time consuming than the CSB (P<.001). The 2 groups were statistically similar regarding the quality of the proximal contacts (P=.281) or occlusal contacts (P=.307) and the relative occlusal forces of ISRs (P=.315). The relative occlusal forces of the ISRs in both groups were significantly lower than those of their contralateral natural teeth (P<.001). ConclusionsDirect digital workflow using SHA-SP was more rapid, saving clinical chairside time, and produced proximal and occlusal contacts of comparable quality with those obtained with CSB. The relative occlusal forces of ISRs in both workflows were lower than their contralateral natural teeth.

Effect of crown retention systems and loading direction on the stress magnitude of posterior implant-supported restorations: A 3D-FEA

This study aimed to investigate the effect of four retention systems for implant-supported posterior crowns under compressive loading using three-dimensional finite element analysis. A morse-taper dental implant (4.1 × 10 mm) was designed with Computer Aided Design software based on non-uniform rational B-spline surfaces. According to International Organization for Standardization 14,801:2016, the implant was positioned at 3 mm above the crestal level. Then four models were designed with different crown retention systems: screw-retained (A), cement-retained (B), lateral-screw-retained (C), and modified lateral-screw-retained (D). The models were imported to the analysis software and mesh was generated based on the coincident nodes between the juxtaposed lines. For the boundary conditions, two loads (600 N) were applied (axial to the implant fixture and oblique at 30°) totaling 8 conditions according to retention design and loading. The von-Mises stress analysis showed that different retention systems modify the stress magnitude in the implant-supported posterior crown. There is a similar stress pattern in the implant threads. However, models C and D presented higher stress concentrations in the crown margin in comparison with A and B. The oblique loading highly increased the stress magnitude for all models. In the simulated conditions, part of the stress was concentrated at the lateral screw under axial loading for model C and oblique loading for model D. The results indicate a possible new failure origin for crown retained using lateral screws in comparison to conventional cement-retained or screw-retained systems.

Bilayer Technique for Alveolar Ridge Augmentation in Pre-Prosthetic Implant Surgery: Indications and Problems

Abstract Background: Prosthetic rehabilitation of missing teeth with dental implant-supported restorations has recently become a predictable treatment option in contemporary dentistry with a highly successful rate. Due to different factors, vertical and horizontal bone loss could present, and the available alveolar bone may not be sufficient for optimum implant position. Ridge augmentation procedures could be applied to increase the volume of the deficient sites for accurate prosthetic implant placement, which assures functional and esthetic stability of tissues around the implants, essential for long-term success. Our study aims to evaluate the efficiency of the bilayer technique of guided bone regeneration for alveolar ridge augmentation procedure in cases of bone deficiency for optimum implant placement and long-term success. Materials and methods: We present several cases of alveolar bone deficiency treated with the bilayer technique – the combination of allo- and xenograft, covered by collagen membrane, with long-term follow-up. The defects were filled with allograft, and a layer of xenograft and barrier membrane was placed above it. This technique combines the benefits of all xenografts and barrier membranes. Results: The bilayer technique with allo- and xenograft and collagen membranes is predictable, with a high success rate and lower morbidity. We have a 100% survival rate of the implants placed in a grafted area with long-term follow-up with excellent aesthetic and functional results. Conclusions: The bilayer technique uses the benefits of two bone graft materials, is associated with less morbidity for the patients, and has excellent long-term results if performed accurately according to indications and technique.

An In Vitro Investigation of the Role of Implant Abutment Materials on the Fracture Resistance and Failure Mode of Implant-Supported Restorations.

Implant-supported restorations have gained popularity in modern dentistry, and the choice of abutment material is crucial for their long-term success. This in vitro study aimed to evaluate the fracture resistance and failure mode of implant-supported restorations using different abutment materials. Ninety standardized implant-supported restorations were included in the study. Abutments made of titanium, zirconia, and a hybrid material (titanium base with a zirconia veneer) were evaluated. Standardized abutments were fabricated, and screw-retained restorations were fabricated using a resin-based composite material. Cyclic loading was applied using a universal testing machine to simulate masticatory forces. Fracture resistance was measured in terms of the number of cycles to failure (NCF), and failure modes were analyzed. The findings indicate that zirconia abutments exhibited higher fracture resistance compared to titanium and hybrid abutments. Longer implants demonstrated higher fracture resistance, suggesting improved stability and resistance to mechanical forces. Increased loading angles resulted in decreased fracture resistance of implant-supported restorations, emphasizing the need for proper occlusal adjustment. Central loading showed higher fracture resistance than lateral and posterior loading locations. The distribution of failure modes varied among the abutment materials, with bulk prosthesis fracture being the most common in the titanium group, while abutment fracture was predominant in the zirconia and hybrid groups. This in vitro study demonstrated that the choice of abutment material significantly influenced the fracture resistance and failure mode of implant-supported restorations. Zirconia abutments exhibited the highest fracture resistance, followed by hybrid and titanium abutments. The failure mode analysis revealed different patterns of failure for each abutment material.

İmplant destekli sabit bölümlü protez tedavisi yapılan hastalarında yaşam kalitesi ve memnuniyetinin değerlendirilmesi

Objectives: This study evaluated the satisfaction of the patients using the oral health impact profile-14 (OHIP-14) and VAS scale after 5-8 years of the treatment. Materials and Methods: A total of healthy 185 implants were selected according to the dental implant health scale accepted by International Congress of Oral Implantologists Consensus (ICOI) and 112 fixed implant- supported prosthesis evaluated for this study. The patient-reported effect was prospectively obtained by measuring oral health impact (OHIP-14) and VAS skale with a a follow-up period ranging from 5 to 8 years. Distribution of variables was checked using 0ne-Sample test. SPSS 22.0 programme was used for the analyses. Results: The patients were defined high satisfaction results after 5-8 years by implant placement. Mean VAS-score for the satisfaction percentage with implant-supported restorations was 87.80 % (SD ± 13.79). Mean OHIP score was 2.82 (SD ± 5.44). The results of OHIP 14 and VAS scores resulted that patient satisfaction with fixed implant supported prosthesis was high in all patients. Conclusions: The fixed implant-supported restorations served high satisfaction results according to the OHIP 14 and VAS results. These restorations has a positive effect to the quality of life for oral health (OHRQoL). Key Words: Quality of life; dental implant; denture ; partial; fixed

Clinical Outcomes of Tooth- and Implant- Supported Restorations Performed in a University-Based Undergraduate Program After 13 to 15 Years.

To assess the clinical concept of patient treatment with fixed tooth- and implant-supported restorations in a university-based undergraduate program after 13 to 15 years. In total, 30 patients (mean age 56 years) who had received multiple tooth- and implant-supported restorations were recalled after 13 to 15 years. The clinical assessment comprised biologic and technical parameters as well as patient satisfaction. Data were analyzed descriptively, and the 13- to 15-year survival rates for tooth- and implant-supported single crowns and fixed dental prostheses (FDPs) were calculated. The survival rate of tooth-supported restorations amounted to 88.3% (single crowns) and 69.6% (FDPs); in implants, it reached 100% for all types of restorations. Overall, 92.4% of all restorations were free of technical complications. The most common technical complication was chipping of the veneering ceramic (tooth-supported restorations: 5.5%; implant-supported restorations: 13% to 15.9%) regardless of the material used. For tooth-supported restorations, increased probing depth ≥ 5 mm was the most frequent biologic complication (22.8%), followed by endodontic complications of root canal-treated teeth (14%) and loss of vitality at abutment teeth (8.2%). Peri-implantitis was diagnosed in 10.2% of implants. The results of this study indicate that the clinical concept implemented in the undergraduate program and performed by undergraduate students works well. The clinical outcomes are similar to those reported in the literature. In general, the majority of biologic complications occur in reconstructed teeth, whereas implant-supported restorations are more prone to technical complications.

A novel technique for retrieval of cement-retained crown from an implant abutment and converting it into a combination prostheses

Dental implant restoration is known to be a widely accepted treatment modality for the replacement of missing teeth and the restoration of masticatory function. Abutment screw loosening is one of the most common causes of failure in single implant-supported restorations, next to loss of osseointegration. Moreover, cement-retained implant-supported prostheses are infamous for their lack of predictable retrievability compared to screw-retained implant-supported prostheses. Management and retrieval of loosening screws are challenging, and this clinical report discusses the procedure for retrieving prosthesis from the abutment of the mandibular molar tooth with minimal damage to the existing restoration, making it possible to be reused.

Nursing cooperation in implant-supported immediate restoration of edentulous jaws under dynamic navigation

Nursing cooperation in implant-supported immediate restoration of edentulous jaws under dynamic navigation

Comparison of Fracture Resistance between Implant-supported Bis-acryl Interim 3-unit FDPs Using Six Different Strengthening Mechanisms: An In Vitro Study.

To investigate six different strengthening mechanisms for three-unit implant-supported provisional restorations. Six techniques of provisional fixed prostheses (PFP) reinforcement were investigated and were assigned to different groups (n = 10): group (ZP) zirconia powder, group (SK8) silk thread wrapped as a figure-of-8 pattern around middle third of abutment, group (RC8) size 00 retraction cord wrapped as a figure-of-8 pattern around middle third of abutment, group (RF8) Resin impregnated glass fiber ribbon wrapped as a figure-of-8 pattern around abutment, group (KV8) Kevlar 29 cord wrapped as a figure-of-8 pattern around middle third of abutment, group (KV) Kevlar 29 strands incorporated in resin mix. Compared against unenforced bis-acryl as control group (CL). Seventy Metal Dies were 3D printed having Soft Tissue Gingiva Mask. Using a custom-made silicone Index, 70 PFP were fabricated (10 of each group) and were cemented to their corresponding metal dies using zinc polycarboxylate cement. All specimens were thermal cycled for 1000 cycles using order of 20 seconds at 55°C and 20 seconds at 5°C with 10 seconds transport. Fracture resistance test was done using universal testing machine. All specimens were loaded to failure. Data were collected, tabulated and statistically analyzed. Kolmogorov-Smirnov normality test showed no significant difference between data in each group. So, data are normally distributed in each group. Descriptive statistics showed higher mean values of CL group (780.8 ± 164) followed by RF8 group (614.2 ± 158.2), followed by RC8 group (550.2 ± 339.2), followed by KV8 group (442.1 ± 198.4), followed by KV group (403.9 ± 306), followed by SK8 group (175.9 ± 90.8), and finally ZP group (136.5 ± 135.7). One-way ANOVA revealed significant difference between the tested groups (p = 0.036). Bis-acryl provisional restorations had better mean fracture resistance values than all other strengthening mechanisms. Bis-acryl provisional restorations did not gain more strength by any of the added materials. One-way ANOVA revealed significant difference between all tested groups. Provisional restorations over implant should be strong enough to serve for the long period of bone and tissue healing. Current materials alone cannot survive for long. It serves as temporization between steps of fixed restorations construction. How to cite this article: Rayyan M, Sayed M, Hujeiry AM et al. Comparison of Fracture Resistance between Implant-supported Bis-acryl Interim 3-unit FDPs Using Six Different Strengthening Mechanisms: An In Vitro Study. J Contemp Dent Pract 2023;24(11):840-846.

Investigating the long-term success rates of implant-supported prosthetic restorations in comparison to conventional fixed or removable prostheses

Background: The choice of prosthetic restoration for missing teeth significantly impacts long-term outcomes and patient satisfaction. Implant-supported prostheses have gained popularity due to their potential advantages over conventional fixed and removable prostheses. Objective: This study aims to investigate the long-term success rates and patient satisfaction associated with implant-supported prosthetic restorations compared to conventional fixed and removable prostheses. Materials and Methods: A retrospective analysis was conducted with a sample of 45 patients, divided equally among three treatment groups: implant-supported prostheses, conventional fixed prostheses, and removable prostheses. Data were collected from patient records, clinical evaluations, and follow-up appointments. Key metrics included survival rates, complications, patient satisfaction (assessed using a standardized questionnaire), and functional outcomes. Statistical analyses were performed using Kaplan–Meier survival analysis, Chi-square tests, and analysis of variance. Results: Implant-supported prostheses demonstrated the highest survival rate (93.3%) compared to conventional fixed (80.0%) and removable prostheses (66.7%). Patient satisfaction scores for comfort, esthetics, and overall satisfaction were significantly higher for implant-supported prostheses (8.7 ± 1.2, 9.0 ± 1.0, 8.9 ± 1.1, respectively) than for conventional fixed (7.5 ± 1.5, 7.8 ± 1.4, 7.6 ± 1.3) and removable prostheses (6.8 ± 1.7, 6.5 ± 1.6, 6.7 ± 1.5). Conclusion: Implant-supported prostheses exhibit superior long-term survival rates and higher patient satisfaction compared to conventional fixed and removable prostheses. These findings support the use of implant-supported restorations as a preferred option for long-term dental prosthetics.

Exploring the Biomechanical Factors Influencing the Success of Combined Prosthodontics and Implant Treatments, Including Load Distribution, Stress Distribution, and Material Selection

Abstract Background: The success of combined prosthodontics and implant treatments is influenced by various biomechanical factors, including load distribution, stress distribution, and material selection. These factors play a critical role in determining the longevity and functionality of implant-supported prosthetic restorations. Aim: This study aimed to explore the biomechanical factors influencing the success of combined prosthodontics and implant treatments, focusing on load distribution, stress distribution, and material selection. Materials and Methods: A prospective observational study was conducted with a sample size of 30 patients requiring implant-supported prosthetic restorations. Standard titanium implants were placed, followed by the application of prosthetic components fabricated from materials such as zirconia, porcelain-fused-to-metal, monolithic zirconia, and composite resin. Cone-beam computed tomography and finite element analysis were used to assess the load and stress distribution. Intraoral sensors measured occlusal load, and data were collected at 3, 6, and 12 months post-prosthesis placement. Results: Posterior mandibular implants exhibited the highest mean occlusal load (220 N), with a significant variability among patients. Zirconia and monolithic zirconia prosthetics demonstrated the lowest mean stress (750 and 700 MPa, respectively) and no fracture incidents, whereas composite resin showed the highest mean stress (900 MPa) and the most fractures. These findings highlight the importance of appropriate material selection and biomechanical planning to prevent implant overload and prosthetic failure. Conclusion: Biomechanical factors, including load and stress distribution, along with careful material selection, are crucial for the success of implant-supported prosthetic restorations. Posterior regions, especially the mandible, require meticulous planning to distribute the occlusal forces evenly. Zirconia and monolithic zirconia materials are recommended for high-load areas due to their superior mechanical properties and fracture resistance.

Implant-supported full-arch restorations using an external spherical implant connection. A case series

Implant-supported full-arch restorations using an external spherical implant connection. A case series

Effects of Photofunctionalisation on Osseointegration and Stability of Dental Implants: A Systematic Review

Introduction: Dental implant osseointegration is crucial for the long term success of implant-supported restorations. Photofunctionalisation (PF), a novel surface modification technique, has been proposed as a means to enhance implant osseointegration. Aim: To evaluate the current evidence regarding the effects of PF on dental implant osseointegration. Materials and Methods: A comprehensive search was conducted in electronic databases, including PubMed, Directory of Open Access Journals, and Google Scholar, for studies published up until August 2022. The search strategy combined keywords related to dental implants, PF, and osseointegration. Two independent reviewers screened the titles, abstracts, and full texts of the identified studies, following predefined inclusion and exclusion criteria. Data extraction and quality assessment using the Cochrane Collaboration’s tool for randomised clinical trials, the ROBINS-I tool for non randomised studies, and the The Newcastle-Ottawa Scale (NOS) for observational studies were performed. Results: A total of five studies met the inclusion criteria and were included in the systematic review. The outcomes assessed included implant stability, osseointegration, and survival rates. The findings of the included studies suggested that PF of dental implants may promote osseointegration by enhancing early bone formation, increasing implant stability, and improving Bone-To-Implant (BIC) contact. Conclusion: The available evidence suggests that PF of dental implants may have a positive impact on osseointegration. However, due to the limited number of studies, further research is needed to provide more definitive conclusions regarding the clinical benefits of photofunctionalised dental implants in pathologically compromised bone sites.

Retrieval of cement-retained zirconia implant-supported crowns with an Er,Cr:YSGG laser

Statement of problemCement-retained implant-supported crowns can be challenging to retrieve from the abutment once technical or biological issues arise. Removal traditionally requires sectioning the crown with rotary instruments, which causes irreversible damage to the crown and potential damage to the periodontal apparatus stabilizing the implant. PurposeThe purpose of this in vitro study was to evaluate an erbium, chromium-doped yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser as a minimally invasive alternative for the retrieval of zirconia implant-supported crowns from titanium abutments. Time, temperature, and structural changes to the crown after retrieval were assessed. Appropriate laser parameters were established for this method of crown retrieval. Material and methodsTwenty zirconia crowns were milled for a maxillary left second premolar based on a CAD-CAM implant analog cast. Ten of these crowns were cemented with a noneugenol zinc oxide dental cement (group Temp) (n=10). The remaining 10 were cemented with a self-adhesive universal resin cement (group Resin) (n=10). Er,Cr:YSGG laser irradiation was performed with the Waterlase iPlus for 1-minute cycles. An attempt was made to remove the crown with a mechanical instrument after each cycle. A type K thermocouple continuously recorded temperature at the level of the abutment. For statistical comparison of decementation time and temperature, the Mann-Whitney test was used (α=.05). Scanning electron microscopy of the nonirradiated and the irradiated crowns was used for analysis of structural and dimensional changes. ResultsA significant difference (P<.001) was found in the time ±standard deviation required to retrieve the crowns between group Temp (02:40 ±00:18 min:sec) and group Resin (05:26 ±00:36 min:sec). A significant difference (P<.001) was found in the mean ±standard deviation temperature recorded between group Temp (24.0 ±1.19 °C) and group Resin (25.7 ±0.66 °C). No structural changes to crowns were observed after irradiation. ConclusionsRetrieval of cement-retained zirconia implant-supported crowns with an Er,Cr:YSGG laser is safe and efficient. Crowns luted with zinc oxide dental cement were retrieved significantly faster while maintaining a significantly lower average temperature than those luted with resin cement. Laser irradiation for decementation did not cause structural changes to zirconia implant-supported crowns. CLINICAL IMPLICATIONSWhen a complication arises with a cement-retained implant-supported restoration, the restoration can be retrieved safely with an Er,Cr:YSGG laser without incurring structural changes. The restoration may then be recemented, avoiding the need to remake the restoration.

A Comparative Evaluation of the Tensile Bond Strength of Cement-retained Restorations on Implant Abutments Subjected to Different Surface Treatments: An In vitro Study

Abstract Introduction: The longevity of cement-retained implant-supported restorations depends upon a strong and durable bond at the metal/cement interface. Various forms of surface treatments of implant abutments have been shown to enhance the retention of cement-retained restorations. The present study was undertaken to comparatively evaluate the tensile bond strength of metal copings luted onto implant abutments subjected to different surface treatments and determine the most effective surface treatment for long-term retention. Materials and Methods: Forty acrylic blocks were prepared, each with an implant analogue placed vertically inside the block and straight abutments tightened optimally onto implant analogues. The samples were divided into four Groups (n = 10) according to surface treatment of implant abutments: Group A – no surface treatment, Group B – sandblasting, Group C – metal primer application and Group D – acid etching. Metal copings were luted onto implant abutments, and the tensile force necessary to debond each metal coping was measured using a universal testing machine. Data were summarised in Mean ± Standard deviation. Groups were compared by one factor analysis of variance (ANOVA) and significance of mean difference between the groups was done by Tukey’s honestly significant difference post hoc test after ascertaining normality by Shapiro-Wilk’s test and homogeneity of variance between groups by Levene’s test. A two-tailed (α = 2) P &lt; 0.05 was considered statistically significant. Results: The highest mean tensile bond strength was recorded for Group C (metal primer application), followed by Groups B, D and A, respectively. Conclusion: Amongst the surface treatments used in the study, metal primer application was found to be most effective in improving the retention of cement-retained prostheses.

The Successful Treatment of Peri-implantitis with Guided Bone Regeneration with an 8-Year Follow-up: Case Report and Literature Analysis

Replacement of missing teeth or unrestorable ones with dental implant-supported restorations is a substantial part of the clinical treatment protocol. However, with the increase in dental implants being placed worldwide, complications with this treatment have also risen in numbers. Complications may result from poor selection of cases with inappropriate treatment planning, occlusal overloading, or with poor follow-up care. The most common complications are the ones related to the presence of inflammation and include perimucositis and peri-impantitis. Peri-implantitis is an inflammatory condition that affects the soft and hard tissues around osseointegrated implants and results in the establishment of a peri-implant pocket and the loss of supporting bone. Nonsurgical therapy, the use of locally and systemically given antibiotics, and surgical regimens intended to replace the lost bone and soft tissue around the implants are among the documented treatment options. The aim of this article is to present a case report on the successful management of a case of peri-implantitis with nonsurgical and surgical approach following the ITI treatment protocol with a 5-year follow-up, along with a review of some of the treatment options used in their management.

CEMENTED AND SCREW-RETAINED IMPLANT-SUPPORTED RESTORATIONS MAY HAVE A COMPARABLE RISK FOR PERI-IMPLANT MUCOSITIS AND PERI-IMPLANTITIS

Reis INRD, Fukuoka GL, Nagay BE, Pannuti CM, Spin-Neto R, Silva EVFD. Incidence of peri-implant disease associated with cement- and screw-retained implant-supported prostheses: A systematic review and meta-analysis. J Prosthet Dent. 2023 Oct 2:S0022-3913(23)00563-2. doi:10.1016/j.prosdent.2023.08.030. Epub ahead of print. PMID: 37793953. None declared. Systematic review and meta-analysis.

Chairside 3-D printed impression trays: a new approach to increase the accuracy of conventional implant impression taking? An in vitro study

PurposeA high transfer accuracy of the intraoral implant position to a model is required, to manufacture implant-supported restorations. However, clinically relevant deviations persist between the intraoral implant position and the model obtained, even for the benchmark conventional custom implant impressions with polyether. Thus, new approaches using 3-D printed impression trays may increase the transfer accuracy of implant impressions. The ability to adjust parameters such as the thickness of the layers and the influence of the openings in the impression tray could potentially affect accuracy.MethodsFour different types of impression trays (n = 10 for each group) for the conventional impression technique were investigated: conventional custom impression tray, customized foil tray, chairside 3-D printed impression tray with the SHERA system, and the Primeprint system using an implant master model with four implants in the posterior region and a reference cube. After plaster model casting, all models were measured using a coordinate measuring machine, and the deviation from the reference dataset was determined. A statistical ANOVA analysis was performed (p < 0.05).ResultsChairside 3-D printed impression trays showed the best results, followed by conventional custom impression trays. Implant impressions obtained using a customized foil tray exhibited the lowest accuracy. Statistically significant differences were observed between 3-D printed impression trays and conventional custom impression and customized foil trays (p < 0.05). Whereas, the implant position did not have any significant influence on accuracy (p > 0.05).ConclusionsChairside 3-D printed impression trays significantly increase the transfer accuracy for implant impression taking.Graphical

Digital PBL-CBL teaching method improves students' performance in learning complex implant cases in atrophic anterior maxilla.

The clinical teaching of esthetic implant-supported restoration of the atrophic maxilla is challenging due to the complexity and unpredictability of bone and soft tissue augmentation. The traditional problem-based learning and case-based learning method (PBL-CBL method) with a full digital workflow (digital PBL-CBL method) provides the students a chance to view clinical cases in a more accurate and measurable way. The aim is to evaluate the effectiveness of the new digital PBL-CBL method in teaching complex implant cases in esthetic area. A full digital workflow of dental implant therapy was established for patients with severely atrophic anterior maxilla. The digital data of cases done in the new workflow was used as teaching materials in digital PBL-CBL teaching. Fifty-four postgraduate students were randomly selected and divided into three groups, including traditional PBL-CBL group (students taught in a PBL-CBL method with no digital cases), digital PBL-CBL group (students taught in a PBL-CBL method with full digital cases) and control group (students taught in didactic teacher-centered method). After training for three months, a study of the students' opinions on the corresponding teaching method was carried out through a feedback questionnaire. A theory test was used to evaluate students' mastery of knowledge about tissue augmentation and esthetic implant restoration. A case analysis was used to determine whether students could apply the knowledge to problem solving. The digital PBL-CBL method resulted in a higher rate of satisfaction than the traditional PBL-CBL method and the didactic teacher-centered method in all items except for "This approach decreases extracurricular work". Case analysis scores of the digital PBL-CBL group were significantly higher than that of the traditional PBL-CBL group and the control group. For the theory test, the digital PBL-CBL group (61.00±6.80) but not traditional PBL-CBL group (55.22±9.86) obtained a significant higher score than the control group (45.11±12.76), although no significant difference was found between the digital PBL-CBL group and the traditional PBL-CBL group. Compared with other methods, students taught with the digital PBL-CBL method showed higher satisfaction and better performance in acquisition of academic knowledge and ability in solving practical clinical problems. The digital PBL-CBL method provided a promising alternative for teaching complex implant cases at the anterior maxilla.

A digital technique for cloning the emergence profile of the interim to the definitive implant-supported restoration

The subgingival contour of implant-supported restorations is key to ensuring the long-term health of the peri-implant bone and soft tissues. This report describes a step-by-step technique used to accurately clone the emergence profile of the interim crown for the definitive implant-supported restoration.