Dose-Dependent Effects of Simulated Clinical Radiotherapy on the Structure and Properties of Root Dentine Anna Victória Costa Serique, Lívia Ribeiro, Julia Menezes Savaris, Luíz Carlos de Lima Dias‐Júnior, Eduardo Antunes Bortoluzzi, et al. Australian Endodontic Journal, 2026 Head and neck radiotherapy (HNRT) can expose teeth to moderate radiation doses, yet the effects on root dentine under clinically relevant conditions remain unclear. This in vitro study compared dentine subjected to 0, 30, or 50 Gy IMRT. Palatal roots from 35 maxillary molars were allocated to non‐irradiated, 30 Gy (oropharyngeal simulation), or 50 Gy (maxillary simulation). Flexural strength, Vickers microhardness, and Raman spectroscopy were assessed, while SEM was qualitatively evaluated. Mechanical and chemical properties did not differ among groups ( p > 0.05). SEM, however, revealed dose‐dependent microstructural changes: fissures and partial tubule obliteration at 30 Gy, and more frequent cracks and complete obliteration at 50 Gy. Under these in vitro simulated conditions, radiotherapy doses preserved bulk properties despite structural alterations. These findings should be interpreted within the limitations of the model, as interactions among experimental factors may influence how microstructural changes affect dentine mechanics.
Disinfection and bacterial extrusion in mesial canals of mandibular molars prepared with intentional foraminal enlargement: an in vitro study General Dentistry, 2026
Exploring Diagnostic Reliability of CBCT for Vertical Root Fractures: A Systematic Review and Meta-Analytical Approach Luiz Carlos de Lima Dias-Junior, Diego Leonardo de Souza, Adriana Pinto Bezerra, Marcio Correa, Cleonice da Silveira Teixeira, et al. International Journal of Dentistry, 2025 This systematic review investigated the different factors associated with the diagnostic accuracy of vertical root fractures (VRFs) with cone‐beam computed tomography (CBCT) scans, assessed by in vitro studies. Studies were screened from PubMed, Embase, Scopus, Web of Science, and Lilacs, up to May 2025. The included studies assessed the diagnostic accuracy of CBCT scans for laboratory‐induced VRFs. The quality assessment of the included studies was performed using the QUADAS‐2 tool. Meta‐analyses were performed using the bivariate model with random effects to produce summary sensitivity (SSe) and specificity (SSp) with a 95% confidence interval (CI). The influence of confounding factors on the accuracy of CBCT images was investigated by meta‐regression models. Covariates were added to the bivariate model to assess the impact on sensitivity, specificity, or both. The quality of evidence of each meta‐analysis was assessed using the GRADE approach. One hundred studies were included. Twenty‐four studies presented a low risk of bias, 22 moderate risk, and 54 high risk. CBCT scans presented a higher sensitivity for the diagnosis of complete VRFs compared to incomplete fractures. The presence of metal posts impaired both sensitivity and specificity. Smaller voxel sizes favored the detection of VRFs in teeth with metal posts. In laboratory settings, the diagnosis of VRFs by CBCT images is mainly affected by the fracture pattern, presence of intracanal materials, and voxel size.
Real-Time Analysis of Changes in Internal and External Root Temperatures Using Different Systems for Activating the Irrigation Solution Maria Eduarda Paz Dotto, Julia Menezes Savaris, Luiz Carlos de Lima Dias-Junior, Tamer Ferreira Schmidt, Lucas da Fonseca Roberti Garcia, et al. International Journal of Dentistry, 2025 Introduction: There is a concern regarding the heating transfer to the periodontal tissues after irrigating solution activation. Therefore, this study analyzed the real‐time changes in internal and external root temperatures using different systems for activating the irrigant.Methods: Two single‐rooted mandibular premolars were chemomechanically prepared. Three orifices were drilled on the root surface at 3, 6, and 9 mm from the apical foramen with a spherical diamond bur. In one tooth, drilling was restricted to the cementum. In another tooth, drilling was performed close to canal dentin. Thermocouple sensors were coupled to the orifices and fixed with resin for temperature measurement. Irrigation was performed with 2.5% NaOCl at 25°C or 45°C. The irrigant was activated for 20‐, 30‐ and 60 s using 3 different systems: passive ultrasonic irrigation (PUI), Ultra X (UX), and endoactivator (EA). For each initial irrigant temperature, time, and activation system, the tests were repeated 8 times, resulting in a total of 96 evaluations for the external and internal root temperatures (n = 48 for each).Results: Data was statistically analyzed with a multilevel linear regression model and intraclass correlation coefficients (ICCs) were calculated. Then, four‐way ANOVA with Bonferroni’s post hoc tests performed intergroup and intragroup comparisons. EA promoted lower temperature increase than PUI and UX (p < 0.05). PUI and UX induced similar internal and external temperature changes when irrigated with NaOCl at 25°C..Conclusion: The initial temperatures (25°C or 45°C) and the activation systems of the irrigant had influence on the internal and external radicular temperatures. The activation period had little influence on root temperature changes, which may be deemed clinically safe.
Effectiveness of supplementary protocols for filling material removal after sealer ultrasonic activation - a laboratory investigation Amanda Freitas da ROSA, Dayana Mara Silva CHAVES, Luiz Carlos de Lima DIAS-JUNIOR, Gabriela Pasqualin GHIDINI, Julia Menezes SAVARIS, et al. Brazilian Oral Research, 2025 Ultrasonic activation of the endodontic sealer makes it difficult to remove the material during endodontic reintervention. Therefore, supplementary removal protocols should be tested to optimize the removal of the remaining filling material. This study assessed the effectiveness of supplementary protocols for filling material removal after sealer ultrasonic activation (UA). Sixty teeth were prepared and distributed into two groups: UA and No UA of the sealer before obturation. Teeth were re-instrumented and two supplementary removal protocols were tested, resulting in six groups (n = 10): NoUA; NoUA+XP (XP-endo Finisher); NoUA+CS (Clearsonic-R1); UA; UA+XP; and UA+CS. Root canals were analyzed under stereomicroscopy and scanning electron microscopy for quantification of the remaining filling material. Considering the total root canal area, the NoUA+CS group had the lowest remaining filling material compared to NoUA+XP, UA+XP and UA+CS groups (p < 0.05). When the root thirds were compared, there was no statistical difference among groups (p > 0.05). The XP-endo Finisher instrument demonstrated the lowest effectiveness when used as a supplementary step. In contrast, the Clearsonic-R1 insert exhibited the highest performance.
Longer light-curing time decreases the effect of ageing on composite resin hardness used in root reinforcement Cleonice da Silveira Teixeira, Filipe Colombo Vitali, Eduardo Antunes Bortoluzzi, Lucas da Fonseca Roberti Garcia Australian Endodontic Journal, 2024 This study evaluated the hardness of a composite resin used for root reinforcement, considering the light‐curing time, root canal region and ageing due to long‐term storage. Twenty incisor roots were reinforced using composite resin, varying the photopolymerisation time (40 or 120 s). Following fibre post cementation, the roots were transversely sectioned into coronal, middle and apical regions. Composite hardness was measured initially and after 18 months of water storage. Data underwent repeated measures analysis of variance and Tukey's post hoc tests. The factors ‘light‐curing time’, ‘root region’ and ‘ageing’ affected the hardness. Significant interactions were observed between ‘light‐curing time × root region’ and ‘ageing × light‐curing time’. Regardless of time, resin hardness in the apical region was lower. After ageing, hardness in the coronal and middle regions decreased when the light‐curing time was 40 s, while no significant effect on hardness was noted with a light‐curing time of 120 s.
