Australian Endodontic Journal最新文献

This study aimed to investigate how varying levels of dentine moisture affect the push-out bond strength of a bioceramic root canal sealer. Forty-eight root canals were randomly divided into four groups according to drying protocol. Moist group: canals were dried until the last paper point appeared dry, Dry group: 95% ethanol was applied for 10 s, Half-dry group: canals were dried with a single paper point for 5 s, Wet group: canals were left completely flooded. All root canals were obturated with iRoot SP. Root slices were prepared from each sample for push-out testing. The data were statistically analysed using the Kruskal-Wallis and Mann-Whitney U test for pairwise comparisons at a significance level of p < 0.05. The dry group had significantly higher bond strength compared to the wet and half-dry groups (p < 0.05), although no statistically significant difference was observed between the moist and dry groups (p > 0.05).

This study evaluated four file systems (WaveOne Gold, Reciproc Blue, ProTaper Next and TruNatomy) for their shaping efficacy in oval-shaped maxillary premolar root canals using micro-CT. Twenty-four extracted premolars, each with two roots, were randomly divided into four groups (n = 6 teeth/group) and instrumented following manufacturer guidelines. Pre- and post-instrumentation micro-CT scans were performed. Key parameters analysed included unprepared canal surface area (% Un-PrepCA), changes in canal area and volume (ΔCA, ΔCV and their percentages), canal transportation and centring ability. Statistical significance was set at p < 0.05. While no significant differences were found in transportation, centring ability or most 3D parameters (ΔCA, ΔCV and ΔSMI), the TRN group exhibited a significantly higher % Un-PrepCA. Conversely, the WOG group achieved a significantly greater % ΔCA compared to TRN and PTN. All systems performed comparably without procedural errors; TRN resulted in the least canal wall contact, while WOG provided the largest prepared canal area.

This study examined the histological response of human dental pulp to Mineral Trioxide Aggregate (MTA) as a pulp-capping agent, with or without Low Level Laser Therapy (LLLT). Thirty-two premolars from 16 patients were treated in a split-mouth design: one side received MTA alone, the other MTA with diode laser-assisted haemostasis and decontamination. After 6 weeks, the teeth were extracted for histological analysis. Results showed that the group with LLLT had a higher incidence of complete dentine bridges (87.5% vs. 68.8%) and thicker bridges (> 0.25 mm: 81.3% vs. 68.8%), though differences were not statistically significant. Inflammation was significantly lower in the LLLT group, with all samples showing moderate inflammation compared to 68.8% in controls, and some severe inflammation cases. Tissue organisation was similar between groups. The study suggests that adding LLLT to MTA reduces pulpal inflammation and promotes more uniform, thicker dentine bridges, indicating improved pulp healing.

Large language models (LLMs) are increasingly used in healthcare, but their performance in endodontic decision-making remains unclear. This study aimed to compare six LLMs in terms of diagnostic appropriateness for endodontic treatment planning. Fifty clinical scenarios were developed and entered into six LLMs (ChatGPT-4o, ChatGPT-3.5, Claude 4, Copilot, DeepSeek-V3, Gemini 2.5). Two specialists scored responses as appropriate or inappropriate. Repeated measures ANOVA and chi-square tests were used for analysis. Claude showed the highest accuracy (76%), followed by DeepSeek and Gemini. ChatGPT-3.5 had the lowest (40%). Significant differences were found between models (p < 0.05). Performance was better on straightforward cases than on complex scenarios. LLMs vary widely in diagnostic accuracy for endodontic cases. While some models show promise, others may provide confidently incorrect recommendations. Caution and human oversight remain essential until domain-specific, fine-tuned models are developed.

This study aimed to investigate the biomechanical impact of root canal anatomical variations and restoration techniques on endodontically treated mandibular second molars using finite element analysis. Five root morphologies were modelled: separated-rooted (S), fused-rooted with V-shaped (F-V), U-shaped (F-U) or Ω-shaped (F-Ω) radicular grooves and single-canal fused-rooted (F-O). Micro-CT scans were performed before and after endodontic instrumentation to generate the finite element models: intact teeth, post-and-core crowns with 2- to 3-mm ferrules and endocrowns with 3- to 4-mm pulp chamber extensions. Under axial/oblique loading, von Mises stress distribution was evaluated. Results showed endocrowns had lower peak stresses than post-and-core crowns in common anatomical variations (S, F-U, F-Ω); F-V showed comparable peak stresses; post-and-core crowns with sufficient ferrule height minimised oblique-load stresses in single-canal teeth (F-O). Pronounced stress concentrations were observed at Ω-shaped groove in post-and-core restored teeth. Comprehensive evaluation of root morphology is critical for optimal restoration planning.

This study investigated the biomechanical behaviour of simulated external cervical resorption (ECR) lesions of varying 3D extent, before and after restoration, using finite element analysis (FEA). Seven maxillary incisors were modelled, representing Patel's classification stages: Group 1–2Bp, 2–2Cp, 3–2Cd, 4–3 Bd, 5–3Cd, 6–3Bp and 7–Control. ECR lesions were restored using Biodentine, with endodontic treatment when the pulp was involved. CBCT scans were used to generate 3D models, and a 240 N bite force was applied to evaluate stress via Von Mises and principal stress values. Pre-treatment, all ECR lesions showed concentrated stress, highest in Group 3Bp (538.11 MPa), correlating directly with lesion height, circumferential spread and pulp proximity. Post-treatment, biodentine reduced stress and improved the safety factor (SF), although most groups still had a failure index > 1, indicating residual fracture risk. Pulp involvement had the greatest biomechanical impact, highlighting the importance of early detection and classification-based treatment planning.