Digital workflow for low-cost 3D printed custom healing abutment based on emergence profile CBCT segmentation

A double-blind randomized crossover trial comparing the esthetic outcomes of CAD-CAM provisional restorations fabricated using CBCT and IOS acquisition methods

OBJECTIVES

This double-blind randomised crossover trial aimed to compare the aesthetic outcomes of CAD-CAM manufactured provisional restorations created using cone beam computed tomography (CBCT) and intraoral scanners (IOS) acquisition methods.

METHODS

Twelve participants (mean-age: 38 ± 5 years) requiring full mouth rehabilitation were included in this crossover trial. Two sets of identical CAD-CAM provisional restorations, differing only in the method of data acquisition (A: CBCT, B: IOS), were fabricated. Restorations were cemented for two weeks, with washout period between interventions. Esthetic evaluations were conducted using clinician and patient-reported outcome questionnaires. Both parametric and non-parametric tests were used to account for data variability: Mann-Whitney U test compared pink esthetic score (PES), white esthetic score (WES), and modified US Public Health Service (USPHS) score. An unpaired t-test compared Oral Health Impact Profile- Aesthetic Questionnaire (OHIP-Aes) scores and Orofacial Esthetic scores.

RESULTS

Clinician-reported outcomes showed significantly better esthetic scores for provisional restorations fabricated using CBCT compared to IOS. CBCT scored higher in Pink Esthetic Score (PES) [Mean rank: CBCT = 16.00, IOS = 9.00; P = 0.012] and White Esthetic Score (WES) [Mean rank: CBCT = 17.25, IOS = 7.75; P < 0.001]. No significant differences were observed for Modified USPHS scores across groups [Mean rank: CBCT = 11.38, IOS = 13.63; P = 0.221]. Patient-reported outcomes indicated no significant differences between groups in OHIP-Aes scores [CBCT = 1.25 ± 1.76, IOS = 1.58 ± 1.62; P = 0.635] or Orofacial Esthetic Index (OFEI) scores [CBCT = 65.75 ± 1.54, IOS = 65.50 ± 1.62; P = 0.703].

CONCLUSION

Both CBCT and IOS acquisition techniques provide aesthetically satisfactory CAD-CAM provisional restorations. CBCT demonstrated significantly higher clinician-reported esthetic outcomes for both pink and white esthetic scores. While patient satisfaction was similar for both methods, CBCT offers practical advantages, including the elimination of separate diagnostic appointments, making it a preferred choice for enhanced esthetic outcomes in CAD-CAM provisional restorations.

CLINICAL IMPLICATIONS

CBCT acquisition methods yield significantly better clinician-reported esthetic outcomes for CAD-CAM provisional restorations compared to IOS. Additionally, CBCT eliminates the need for separate diagnostic appointments, reducing treatment time and number of visits, while both methods provide similar satisfactory patient-reported outcomes.

CLINICAL TRIAL REGISTRATION NUMBER

Approval number: CTRI/2023/03/050410.

Peri-implant tissue definition and registration with a 3D-printed emergence profile former on titanium stock healing abutment: A dental technique and clinical report

Recent focus has shifted toward refining the soft tissue emergence profile to enhance aesthetics, support peri-implant health, and ensure long-term success. Traditionally, titanium stock healing abutments or chairside-customized abutments were used to shape peri-implant tissues and develop the emergence profile for implant-supported prostheses. However, advancements in digital dentistry now allow for more precise customization and increased treatment efficiency. This case report introduces a novel approach to shape the peri-implant tissues using a 3D-printed emergence profile former retained by a titanium stock healing abutment. The 3D-printed emergence profile former reduced chairside time and simplified registering the gingival tissue contours and implant position with an intraoral scanner. Following removal, the peri-implant soft tissues displayed enhanced volume buccally, creating an aesthetically pleasing restoration in a site with a notable horizontal tissue deficiency.

Advantages and drawbacks of different methods to measure marginal gaps in fixed dental prostheses: A scoping review

OBJECTIVES

This review aimed to compare traditional and digital methods to assess marginal gaps in fixed dental prostheses. Each method's characteristics, advantages, and limitations were identified and discussed, also addressing the knowledge gaps in the current scientific literature.

DATA

Studies comparing currently available techniques for marginal gap examination were investigated. The main techniques analyzed were the Cross-Sectional Method (CSM), Direct View (DV), Silicone Replica Technique (SRT), Dual-Scan Method (DSM), Triple-Scan Method (TSM), Optical Coherence Tomography (OCT), and Micro-Computed Tomography (MCT).

SOURCES

Two experienced independent reviewers screened online databases (MEDLINE via PubMed and Scopus) to identify studies published in English up to March 2024. References from primary studies and the main peer-reviewed scientific journals were manually searched.

STUDY SELECTION

From an initial pool of 8126 articles, the reviewers meticulously selected 25 in vitro studies on objective comparisons between two or more methods for assessing marginal gaps in fixed dental prostheses on natural teeth. Publications that assessed marginal gaps in implant-supported fixed dental prostheses were excluded.

CONCLUSIONS

This study highlights that while traditional methods like CSM and SRT are widely used and validated, they have limitations in comprehensive gap assessment, often neglecting recommended measurement points. The DV technique, focusing solely on external gaps, may be less relevant for modern assessments. Conversely, three-dimensional techniques like TSM, DSM, OCT, and MCT offer a more thorough evaluation of dental restoration fit. Moreover, digital methods such as TSM and DSM have a significant potential for future clinical application.

CLINICAL SIGNIFICANCE

This review examined methods for evaluating marginal gaps in fixed dental prostheses. The review aids dental professionals and researchers in choosing the most suitable technique for clinical in vivo or laboratory assessment of the marginal adaptation of dental restorations. This study also indicates the need for an established and standardized assessment protocol for the marginal fit.

Immediate Implant and Customized Healing Abutment for a Periodontally Compromised Socket: 1-Year Follow-Up Retrospective Evaluation

Immediate dental implant placement with or without immediate loading is reported in daily dentistry and implantology, but these procedures are not common in the case of periradicular and periapical lesions around the tooth needed to be replaced. In the following retrospective evaluation, 10 cases with a 1-year follow-up were selected to propose the technique of an immediate provisional non-loading prosthesis being delivered on the same day of the post-extraction implant placement in multiradicular teeth affected by chronic periradicular and periapical lesions. Post-extractive sockets underwent immediate dental implant placement by filling the empty space with sterile, re-absorbable gelatin sponges. The widths of the alveolar ridge were measured on three-dimensional radiographs before and after the operation, 4 and 12 months later. Non-parametric statistics were performed to compare the outcomes over time with a level of significance of 0.05. Comparing the preoperative cross-sectional images of cone beam computerized tomography (CBCT) scans to the postoperative ones, it was noted that changes in the crestal ridge width, ΔCW, (compared to baseline) were negligible and not clinically appreciable. However, while ΔCW at 4 months appeared to be negative (-0.17 ± 045 mm), crestal width at 12 months was at the same level as the baseline (ΔCW = 0.02 ± 0.48 mm), with a significant difference between 4 and 12 months (p-value = 0.0494). Immediate implant placement with an immediate non-loading provisional customized healing abutment of polyether-ether-ketone placed into the post-extractive sockets with asymptomatic and large chronic periapical and periradicular lesions could represent a further treatment strategy for patients' rehabilitation and soft tissue preservation to replace a hopeless tooth.