Sahar Molaei

Purpose: This systematic review, conducted per PRISMA guidance, evaluated clinical outcomes of titanium-base (TiB) versus multi-unit (MU) abutments in immediate-loading dental implant protocols, focusing on implant survival, prosthetic and biological complications, and patient-reported outcomes. Methods: PubMed and Scopus were searched for original English-language clinical studies published between 2001 and 2025, including RCTs, cohort studies, and clinical series with at least 12 months of follow-up. Only studies evaluating TiB and MU abutments in immediate-loading protocols were included. Due to heterogeneity in study designs, case selection, outcome measures, and follow-up duration, a narrative descriptive synthesis was performed without pooled statistical analysis. Results: Seventeen clinical studies met the inclusion criteria. Both TiB and MU abutments showed high implant survival rates, generally in the high 90 s. TiB abutments performed well in single-tooth anterior restorations, showing fewer mechanical complications and better esthetic ratings. MU abutments were predominantly used in full-arch cases, demonstrating reliable long-term function but with higher mechanical maintenance needs. Marginal bone loss remained within acceptable limits across studies. Patient-reported outcomes were inconsistently assessed, though TiB tended to score higher for esthetics and MU for functional comfort. Conclusions: Both TiB and MU abutments effectively support immediate loading when primary stability and proper prosthetic planning are achieved. TiB may be preferable for esthetic single-tooth cases, while MU abutments remain suitable for full-arch rehabilitation. The limited number of head-to-head studies highlights the need for well-designed randomized trials with standardized outcomes and validated patient-reported measures. Graphical

Performing endodontic treatment on calcified root canals is highly challenging and time‐intensive. Even with the assistance of a dental operating microscope, the probability of iatrogenic errors is high. The aim of this report is to present successful endodontic treatments for severely calcified maxillary anterior teeth using a 3D endodontic sleeveless guide, providing a basis for upcoming validation through more comprehensive research. A 25‐year‐old male patient was referred to the dental office with a chief complaint of pain and swelling of his Tooth 2.2 who explained a previous history of trauma. On clinical examination, periapical swelling was observed, and the tooth demonstrated tenderness to percussion and palpation in the periapical region. Radiographic findings included a severely obliterated pulp chamber and a calcified root canal with periapical radiolucency. In order to perform the root canal treatment with an endodontic guide, an optical impression was carried out using an intraoral scanner. Data from the impression and CBCT files were aligned and sent to the dental laboratory. A virtual copy of a drill was superimposed onto the scans in an optimal position that provided access to the root system, using Exoplan software. A digital model was created and exported as an STL file and transferred to a 3D printer to produce a template. Despite several limitations, successful root canal treatment was conducted. At the 6‐month follow‐up visit, the patient reported no symptoms, and periapical radiography showed a diminished periapical lesion. Static endodontic guidance provides an opportunity to have more reliable and predictable outcomes in treating complex root systems, even in the presence of minor issues such as transportation and file separation.

Objectives. The impression-taking technique is one of the most critical factors that not only prevents the shrinkage caused by polymerization but also enhances the accuracy of implant impressions. Also, choosing the right time of taking impressions after splinting implants is one of the important criteria that affects the impression-taking technique. Accordingly, the present study aimed to evaluate the accuracy of different splint methods for implant impressions made at different times. Methods. In this in vitro study, a two-piece metallic index was prepared, and the patients jaw was simulated by placing self-cured acrylic resin in the lower part of the index. Then, two holes were made in the acrylic resin at a specific distance from each other, and the analogs were placed in these holes. Splinting of impression copings was carried out with autopolymerized acrylic resin (GC Pattern resin LS, GC America Inc., USA), and an open tray impression approach was performed. Thirty-six casts in three groups (n=12) were fabricated from the acrylic model. After scanning the casts, the impression accuracy was compared between the three study groups by measuring the distance between the outer portions of the scan bodies screw-retained on implant analogs inside the cast using the Exocad software (2015.07 version). Group 1: splinting impression copings with autopolymerized acrylic resin and impression making immediately after the setting time (4 minutes); group 2: splinting and impression procedure after 17 minutes with splint sectioning and reconnection; group 3: splinting and impression procedure after 24 hours with splint sectioning and reconnection. The data were analyzed using SPSS 17 using the KruskalWallis test. Results. The mean distance measured in group 1 was 19.14±0.029mm, which was significantly lower than the main model. The distances were 19.15±0.039 and 19.159±0.33mm in groups 2 and 3, respectively. These two groups were not significantly different from the main model. Moreover, the mean distance measured in the three impression techniques was similar. Conclusions. There was no significant difference in the measurements between group 2, group 3, and the main model. Therefore, dentists can make an impression after 17 minutes to reduce chair time.