Australian Endodontic Journal最新文献

Apical periodontitis is an inflammatory condition resulting from microbial invasion in the root canal system, causing periapical tissue destruction and bone resorption. This study investigated melatonin's effects, known for its antioxidant and anti-inflammatory properties, on experimentally induced apical periodontitis in rats. Three groups of rats were studied: control, apical periodontitis and apical periodontitis with melatonin treatment. Proinflammatory cytokines and enzyme levels in blood serum were measured, and micro-CT analysis assessed bone resorption. Results showed significantly elevated cytokines and enzyme levels in the apical periodontitis group compared to the control. However, in the melatonin-treated group, these levels were significantly reduced (p < 0.01–0.001). Micro-CT analysis indicated decreased periapical resorption cavity volume and surface area with melatonin treatment. This suggests that systemic melatonin administration can mitigate inflammation and reduce bone resorption in experimentally induced apical periodontitis in rats, potentially holding promise for human endodontic disease treatment pending further research.

This study aimed to assess the association between genetic polymorphisms in BMP2 (rs1005464 and rs235768), BMP4 (rs17563), SMAD6 (rs2119261 and rs3934908) and RUNX2 (rs59983488 and rs1200425) and pulp stones (PS). A total of 117 participants, consisting of 63 individuals with PS and 54 without PS, were included. Digital radiographs and a demographic/clinical questionnaire were used. Genomic DNA from salivary cells was genotyped via real-time polymerase chain reaction. Statistical analyses, including Chi-Square, Fisher's exact tests, Poisson regression and dimensionality reduction, were conducted. The rs2119261 polymorphism in the SMAD6 gene showed an association with genotype distribution in the recessive model (p = 0.049). The T–T haplotype in the SMAD6 gene (rs2119261 and rs3934908) was more prevalent in the control group and significantly linked with PS (p = 0.029). No associations were found between PS risk and genetic polymorphisms in BMP2, BMP4 and RUNX2. Polymorphisms in the SMAD6 gene were associated with PS.

Orthodontic cases requiring tooth extraction sometimes involve post-traumatic incisors. For adolescent cases in which trauma causes the maxillary unilateral incisors to be missing or have poor prognoses, it is worth considering these teeth as candidates for extraction, and this unusual approach is seldom reported in the literature. An adolescent patient with a missing maxillary left lateral incisor and an ankylosed maxillary left central incisor sought treatment for dental protrusion and crowding. An unusual orthodontic approach was used, which involved the extraction of the maxillary left central incisor and mandibular first premolars. After treatment, the maxillary right central incisor was successfully translocated across the midpalatal suture and transformed into the left central incisor. Additionally, well-aligned teeth and enhanced smile aesthetics were achieved, and the treatment outcomes remained stable throughout the follow-up period.

This study investigated the root canal morphology of fused-rooted mandibular second molars based on the pulp chamber floor (PCF) and analysed the correlation between the external morphology of the radicular groove, and the internal morphology of the PCF and root canal configuration. A total of 291 fused-rooted teeth collected from the Chinese population were scanned using micro-computed tomography and a dental operating microscope was used for observing the PCFs. The classification of the PCF and root canal configuration were identified according to modified Min et al.'s and Gao et al.'s classifications, respectively. Additionally, a new radicular groove classification was proposed. The correlation among these morphological characteristics was investigated using the chi-square test and Fisher's exact test (p < 0.05). The results showed that 74.2% of teeth had C-shaped PCFs, while 21.0% had non-C-shaped PCFs. As for the root canal configurations, 37.5% of teeth were merging type, 40.9% were symmetrical type, and 14.8% were asymmetrical type. Statistical analysis revealed a significant correlation between the PCF types and the root canal configurations (p < 0.001). The dominant root canal types for teeth with C-shaped PCFs were merging and symmetrical types, while the asymmetrical type was not identified in non-C-shaped PCFs. In addition, significant morphological association between the root canals and radicular grooves was also revealed (p < 0.001). Teeth with different PCF morphologies exhibit specific patterns of root canal category distribution. Understanding the morphological nuances of the root canal based on the PCF can assist clinicians in predicting and identifying the canal configuration beneath the visible orifice.

The aim of this study was to assess whether calcium silicate root fillings prevent bacterial penetration and to determine how bacteria penetrate roots. Extracted single-rooted, single-canal human teeth were decoronated, prepared and filled with ProRootMTA or Biodentine (n = 12 each). Positive and negative (n = 2 each) controls were not filled. A two-chamber model was used with Streptococcus gordonii. The lower compartment was evaluated for turbidity over 150 days. Roots were split and examined for bacteria via SEM. The chi-squared test was used for comparisons (α = 0.05). Experimental groups had bacteria in their coronal thirds. Tubules contained bacteria in 90.9% and 91.7% of areas examined in the Biodentine and ProRootMTA groups, respectively, with no significant difference (p = 0.914). Experimental and negative roots had no turbidity with no significant difference between Biodentine and ProRootMTA (p = 1.000). Positive controls had turbidity. Bacteria penetrate roots via dentine tubules of root-filled teeth. Biodentine was comparable to ProRoot MTA.

The objective of the study was to compare 4 mechanical properties of two 3-D printing resins with dentine. Four mechanical tests were performed on dentine specimens, VeroClear resin and Splint resin with 15 samples each. Vickers hardness test, samples were subjected to a 300-g load for 10 s. Flexural strength test, 8-millimetre, beam-shaped specimens were tested using the three-point bending method. Drilling force was measured on flat-surface specimens. Intra-canal torque was measured on specimens imitating root canals. The results were analysed using the Kruskal–Wallis and Mann–Whitney tests with adjusted Bonferroni's p-value (p < 0.05). Dentine exhibited the highest mechanical properties in all the tests. VeroClear's flexural strength and drilling force were higher, while the surface hardness was lower than that of Splint resin. The intra-canal torque of dentine and VeroClear resin were not significant and higher than that of Splint resin. VeroClear's mechanical properties were closer to dentine than Splint resin.