Objective. The aim of the study was to investigate the root canal morphology of maxillary first and second premolars in a Saudi population using Cone-Beam Computed Tomography (CBCT).Methods. This retrospective cross-sectional study assessed CBCT images of 707 Saudi patients. The number of roots and canal configuration were identified based on Vertucci’s classification. Fisher’s exact Chi-square tests were performed to analyze the association between sex and number of roots and sex and root canal configuration.Results. Most teeth had two roots in maxillary first premolars (75.1%) and one root in maxillary second premolars (85.2%). Type IV was the most prevalent canal configuration in maxillary first premolars (69.1%), while Type I was the most in maxillary second premolars (49.4%). All types of canal configurations were observed in maxillary premolars except Type VII for the maxillary second premolar. Chi-square tests showed no significant association between gender and number of roots and sex and root canal configuration in both maxillary first and second premolars although higher number of roots was seen in men (P > 0.05).Conclusion. Most maxillary first premolars had two roots with Type IV being the most predominant canal configuration, while a single root with Type I canal configuration was the most frequently observed morphology in maxillary second premolars. In maxillary first premolars, 21.3% had one canal apically, 75.4% had two canals apically, and 3.3% had three canals apically. In maxillary second premolars, 80.2% had one canal apically, 18.9% had two canals apically, and 0.9% had three canals apically.

To investigate the root canal morphology of mandibular first and second premolars using Cone-Beam Computed Tomography (CBCT) in a Saudi population. CBCT images of 707 patients, number of roots and canal configuration were identified and categorized according to Vertucci classification. Bilateral symmetry and association between gender and number of roots, as well as gender and root canal configuration were investigated. Majority of the patients had one root and type I root canal configuration in mandibular first (96.4%) and second premolar (95.6%). All types of canal configurations were observed except Type VII for the mandibular first premolar, and Types VI and VII for the mandibular second premolar. High degree of bilateral symmetry was seen in both mandibular first and second premolars in terms of the number of roots and canal configuration; 93.8% and 97.8%, respectively. There was an association between gender and number of roots (P = 0.04) and gender and root canal configuration in mandibular first premolar (P = 0.030). Single-root with type I canal configuration was the most prevalent of mandibular premolars in the Saudi population. However, incidence of more than one root with different canal configurations was detected.

The cyclic fatigue resistance of ProTaper Universal (PTU), ProTaper Gold (PTG), and ProTaper Next (PTN) nickel titanium (NiTi) rotary files was evaluated. Fifteen instruments of each type were selected, totaling 195 files. The instruments were rotated until fracture in an artificial canal with dimensions corresponding to the dimensions of each instrument tested: +0.1 mm in width and 0.2 mm in depth, an angle of curvature of 45°, a radius of curvature of 5 mm, and a center of curvature 5 mm from the instrument tip. The fracture surfaces of three representative samples of each subgroup were examined using scanning electron microscopy (SEM). Time to fracture was analyzed via analysis of variance and Tukey’s tests (P < 0.05). PTG F1 and F2 had significantly higher resistance than PTU F1 and PTN X2, and PTU F2 and PTN X3, respectively. PTN X2 showed a significantly higher resistance than PTU F1. The PTG series demonstrated superior cyclic fatigue (CF) behavior compared with that of the PTU and PTN series.

Purpose. Despite the good sealing ability and biocompatibility of mineral trioxide aggregate (MTA), its slow setting, high degradation, and weakness limit its use in surgical endodontics and high stress-bearing areas. This study aimed to develop two new liquids to control these drawbacks. They were prepared from calcium chloride, fumed silica, and hydroxyapatite or calcium phosphate and coded “H” and “P,” respectively. Methods. Portland cement, Grey ProRoot® MTA, and white ProRoot MTA were mixed with distilled water (control) or liquid “H” or “P.” The pH, setting time, degradation rate, leachant/precipitate’ composition, compressive strength, and morphology were assessed. Results. Both liquids maintained MTA’s high alkalinity and reduced the setting time by 1-2 orders of magnitude. Both liquids, H in particular, significantly reduced the degradation rate of Grey ProRoot and White ProRoot MTA®. Calcite has been identified as the main phase of the leachant or precipitate formed during the cement’s degradation. Calcium hydroxide or hydroxyapatite was also identified with Grey ProRoot MTA mixed with H liquid. These liquids also significantly increased the compressive strength with no statistical differences between them; this was associated with the production of dense, consolidated structures. Conclusions. The modified MTA could be used in surgical endodontics and high stress-bearing areas.

Invasive cervical resorption (ICR), a commonly misdiagnosed condition, is an aggressive form of external tooth resorption that contributes to periodontal tissue inflammation and deepening of the periodontal pockets. Herein we report the case of a patient, exhibiting ICR and elaborate the effects of a non-surgical approach in the amelioration of this condition. A 21-year-old female reporting intermittent pain at the upper left side, multiple restorations, no trauma history, and having received orthodontic treatment was studied. Localized erythematous swelling was noted at the buccal interdental papilla between the left maxillary first molar and second premolar. The diseased pulp and tissue in resorption were removed and the root canal system including the defect were sealed using gutta percha/AH Plus and mineral trioxide aggregate (MTA). At the one-year recall, the tooth showed no symptoms and responded normally to percussion and palpation. The surrounding periodontium exhibited a normal color and the probing depth was normal. Radiographic examination showed a restoration of crestal alveolar bone and good adaption to MTA. Non-surgical root canal treatment in conjunction with resorption defect orthograde repair with MTA was found to be an effective treatment option in the elimination of ICR. Early diagnoses are recommended in order to employ non-surgical approaches for management of ICR instead of surgical interventions.