Effects of CBCT acquisition protocol and additional superimposed computerized optical impressions on the accuracy of root canal length measurements: an ex vivo study.

AIM: The purpose of the present investigation was to evaluate the accuracy of root canal length (RCL) determination according to CBCT acquisition protocol and evaluate the influence of additional superimposed computerized optical impressions. MATERIALS AND METHODS: CBCT scans with low-dose (LD) and high-definition (HD) protocols as well as computerized optical impressions of 30 extracted human molars were acquired. Sicat Endo software (Sicat) was used for CBCT RCL measurements with (LD+, HD+) and without (LD-, HD-) a superimposed optical impression. To evaluate the accuracy, absolute differences between test groups and the actual root canal length (ARCL) were calculated and statistically analyzed using the Wilcoxon rank sum test. RESULTS: Absolute differences between the ARCL and the tested measurement methods varied significantly (P < 0.05). Both higher resolution and additionally superimposed computerized optical impression improved measurement accuracy. Mean differences compared with the ARCL were 0.26 mm (HD+), 0.34 mm (HD-), 0.43 mm (LD+), and 0.66 mm (LD-). 93.4% of all measurements in the HD+ group were within the limits of ± 0.5 mm. CONCLUSION: Both resolution and superimposition of additional computerized optical impressions have a significant influence on RCL measurements using CBCT.

Apical periodontitis after intense bruxism.

BACKGROUND: Bruxism is known to cause masticatory muscle pain, temporomandibular joint pain, headaches, mechanical tooth wear, prosthodontic complications and cracked teeth. Less known to the practitioner, and described only experimentally in literature, is that bruxism can also damage the pulp. To our knowledge, this is the first known clinical case of a patient developing apical periodontitis due to bruxism. CASE PRESENTATION: This article presents the case and successful treatment of a 28-year-old healthy male patient with apical periodontitis on teeth 36 and 46 requiring root canal treatment after an intense phase of bruxism. Due to an unclear diagnosis, treatment had been delayed. CONCLUSIONS: Incomprehensible tooth pain can be the result of bruxism. Practitioners need to be informed that intense bruxism can possibly lead to apical periodontitis. It is important, therefore, that a thorough anamnesis is collected and taken into account during diagnostics.

Accuracy of different generations of apex locators in determining working length; a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: The accurate determination of working length has a major influence on the prognosis of root canal treatment. Electronic Apex Locators (EALs) appear to be excellent tools for the determination of working length (WL). This study aimed to assess the accuracy of four generations of EALs. MATERIALS AND METHODS: For the purpose of the present review study, articles on different generations of EALs were selected from the PubMed, Cochrane Library, Google Scholar, and ScienceDirect databases using the search term apex locators. In addition, eligibility criteria were set and used for the inclusion of articles. RESULTS: Fifteen studies satisfied the eligibility criteria and were included in this study. According to the results of four meta-analyses, the Cochran's Q-values were 3.042, 4.569, 0.636, and 0.443. The I2 value of four heterogeneity tests was zero (I2 = 0). In addition, the effect sizes (risk ratios) of the four meta-analyses were 1.040, 0.997, 0.935, and 0.959. CONCLUSION: Based on the findings of this study, all four generations of apex locators under review were found to be accurate in measuring working length. Hence, the generation of an apex locator does not play a significant role in how accurately electronic devices determine working length. In addition, the results suggest that more clinical and laboratory trials are required in order to evaluate the accuracy of different generations of EALs in measuring working length.

Biodentine Inhibits the Initial Microbial Adhesion of Oral Microbiota In Vivo.

This study aimed to evaluate the in vivo initial microbial adhesion of oral microorganisms on the biomaterial Biodentine compared to MTA and AH Plus. Cylindrical samples of the materials were prepared, and dentin slabs served as a control. An individual intraoral lower jaw splint served as a carrier for the samples and was worn by six volunteers. The specimens were worn for 120 min. Adherent bacteria were quantified by determining the colony-forming units (CFUs), while the visualization and quantification of total adherent microorganisms were facilitated by using DAPI and live/dead staining combined with fluorescence microscopy. Bovine dentin had a significantly higher number of aerobic CFUs compared to Biodentine (p = 0.017) and MTA (p = 0.013). The lowest amounts of DAPI-stained adherent microorganisms were quantified for Biodentine (15% ± 9%) and the control (18% ± 9%), while MTA showed the highest counts of initially adherent microorganisms (38% ± 10%). Significant differences were found for MTA and Biodentine (p = 0.004) as well as for MTA and the control (p = 0.021) and for AH Plus and the control (p = 0.025). Biodentine inhibited microbial adherence, thereby yielding an antimicrobial effectivity similar to that of MTA.

Comparison of the efficacy of different Ni-Ti instruments in the removal of gutta-percha and sealer in root canal retreatment.

AIMS: To evaluate and compare the efficacy of four rotary instrumentation systems in root canal retreatment and to determine retreatment time. MATERIALS AND METHODS: To achieve the purpose of this study, canals of 60 distal roots in mandibular molar teeth were selected and randomly divided into four groups A, B, C and D (n = 15). Using step-back technique, the canals were prepared and filled with gutta-percha and AH Plus employing cold lateral compaction technique. The root filling material was removed with the following retreatment systems: Group A: Mtwo R, group B: D-RaCe, group C: ProTaper R and group D: R-Endo. In order to record retreatment time, a stopwatch was used. The samples were split longitudinally, examined under a stereomicroscope, photographed and assessed with AutoCAD software. Finally, the percentages of remaining filling material were calculated and the extracted data were analyzed using one-way ANOVA and Tukey HSD test. RESULTS: All examined groups showed traces of remaining filling material within the canals. No statistically significant difference was found among the four groups in the coronal, middle, and apical thirds. The same result was obtained with regard to retreatment time (P > 0.05). However, within each one of the groups, significant difference was observed in the three regions (P < 0.05). CONCLUSIONS: Based on the findings of this study, none of the examined systems could completely remove root filling material from the root canals. However, they were all found to be effective in this regard. The most amount of remaining filling material was found in the apical third.

Guided endodontic access of a calcified mandibular central incisor using a software-based three-dimensional treatment plan.

This case report describes the digital and clinical workflow of a guided endodontic access approach in a mandibular central incisor with pulp canal calcification (PCC). The access to the remaining pulp space was planned virtually using cone beam computed tomography (CBCT) and the Sicat Endo software (Sicat, Bonn, Germany). Sicat produced the corresponding Accessguide after matching a digitized cast model and the virtual treatment plan. The clinical access was prepared using a carbide bur with a diameter of 1.2 mm. After the root canal was localized successfully, it was disinfected chemomechanically, dried, and obturated using a warm vertical compaction technique.