Radiographic Criteria for Differential Diagnosis Between Vertical Root Fracture and Apical Periodontitis in Single-Rooted Endodontically Treated Premolars Using Cone-Beam Computed Tomography.

INTRODUCTION: This study explores the differences between the patterns of bone defects associated with vertical root fracture (VRF) and apical periodontitis (AP) in single-rooted endodontically treated premolars (SRETPs) based on cone-beam computed tomography (CBCT) data. METHODS: Eighty-four SRETPs were extracted and categorized into the VRF and AP groups. On preoperative CBCT images, the location of bone defects according to the root thirds in buccolingual and mesiodistal directions across the study groups were compared. RESULTS: The majority of bone defects in the VRF group were longitudinal and combined, involving more than one root thirds in buccolingual and mesiodistal directions simultaneously. A uniform approach to comparing bone defects using the sites of periradicular area with bone loss as a comparison unit was developed. In the VRF group, bone loss sites in the middle and coronal thirds were detected more often and were located mainly buccolingually compared with the AP group (P < .001). CONCLUSION: Bone defects in the middle or middle and coronal root thirds in the buccolingual direction may be potential radiographic signs useful in differentiating between VRF and AP in SRETPs. The introduction of the uniform approach to assessment of bone loss patterns will give practitioners a single simple tool and improve the quality of endodontic treatment.

Treatment of an Endo-Perio Lesion with Ozone Gas in a Patient with Aggressive Periodontitis: A Clinical Case Report and Literature Review.

The pulp and periodontium have obvious relationships that have been described in many studies. Pulp infections may affect periodontal tissues and vice versa. Teeth with endo-perio lesions have a worse prognosis than isolated endodontic or periodontal lesions. Elimination of endodontic and periodontal infections is essential for successful treatment, so co-operation between endodontists and periodontists is necessary. In this clinical case, a 44-year-old male presented with primary periodontal disease with secondary endodontic involvement in his lower right canine because of aggressive periodontitis. There was 10 mm of clinical attachment loss and 8 mm periodontal pocket mesial from the tooth and bone radiolucency periapical and lateral from the root. Periodontal therapy was followed by endodontic treatment. Periodontal therapy included root scaling and planing, treatment of the periodontal pocket with ozone gas, systemic antibiotics, oral hygiene instructions, and chlorhexidine rinsing. Endodontic therapy included root canal instrumentation with rotary endodontic files, irrigation, root canal treatment with ozone gas, and obturation with lateral compaction. Radiographs at a 6-month follow-up appointment showed complete healing of the periapical lesion and alveolar bone lateral to the root. Using an interdisciplinary approach to treat endo-perio lesions provides favorable clinical outcomes. Ozone therapy is beneficial for the successful treatment of endo-perio lesions with narrow periodontal pockets in patients with aggressive periodontitis and poor prognosis.

The influence of centrifugation and inoculation time on the number, distribution, and viability of intratubular bacteria and surface biofilm in deciduous and permanent bovine dentin.

The present study aimed to assess the influence of centrifugation and inoculation time on the number, distribution, and viability of intratubular bacteria and surface monospecies E. faecalis biofilm. MATERIALS AND METHODS: Forty-four semicylindrical specimens cut from primary (n = 22) and permanent (n = 22) bovine teeth were randomly assigned to the experimental groups. Teeth of each type were inoculated with E. faecalis with and without centrifugation for 1 and 14 days. The number, localization, viability of bacteria and depth of their penetration were assessed with bacterial culturing of dentin shavings, scanning electron microscopy (SEM) and confocal laser electron microscopy (CLSM). Three-way ANOVA with post-hoc Tukey test were used to assess the influence of different experimental setups on dentin infection. RESULTS: Severe dentin infection was observed in permanent and deciduous teeth after centrifugation and 1-day incubation: bacteria reached the full length of dentinal tubules and colony-forming units were too numerous to count. The volume of green fluorescence didn't differ significantly in permanent teeth compared with deciduous (p = 1.0). After 1-day stationary inoculation, small number of cultivable bacteria and few viable bacteria in dentinal tubules were found in both groups. After 14-day stationary inoculation, the dentin infection according to CLSM was deeper in deciduous teeth compared with permanent (p = 0.006 and p = 0.019 for centrifugation and stationary inoculation, respectively). CONCLUSION: The most even and dense dentin infection was observed in primary and permanent bovine teeth after centrifugation and 1-day inoculation, and in deciduous teeth after 14-day stationary inoculation.

Quantitative Assessment of Dentinal Tubule Disinfection in Absence of Biofilm on Root Canal Walls: An in vitro Study.

Introduction: This study aimed at assessing the quantitative effect of calcium hydroxide, 2% chlorhexidine gel, and 1.5% chlorhexidine linked to xanthan gel specifically against intratubular bacteria. Methods and Materials: Fifty-two semi-cylindrical bovine dentin specimens were infected with Enterococcus (E.) faecalis by centrifugation with subsequent 7-days incubation. The surface of specimens was disinfected with 3% H2O2. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and the count of bacterial colony-forming units (CFU/mg) were used to assess dentin infection. A total of 40 specimens were incubated for 2 weeks with one of the intracanal medication applied (10 samples for each group): 1) calcium hydroxide, 2) 2% chlorhexidine gel, 3) 1.5% chlorhexidine linked to xanthan gel and 4) sterile saline. Final passive ultrasonic irrigation with 3% sodium hypochlorite was performed in half of the total specimens. The effect of intracanal medications and irrigation against intratubular bacteria was assessed by bacterial culturing of dentin shavings. Two-Way ANOVA model was applied followed by post-hoc Tukey's test for multiple pair-wise comparisons of mean CFU/mg values. Results: SEM, CLSM, and bacterial culturing confirmed the absence of the surface biofilm on the root canal wall and showed vital intratubular bacteria at the depth up to 700  m. Two-week application of 1.5% chlorhexidine with xanthan gel and 2% chlorhexidine gel significantly decreased intratubular bacterial counts compared with saline (P=0.0003 and P=0.0005, respectively). Subsequent passive ultrasonic irrigation with 3% sodium hypochlorite significantly reduced the number of intratubular bacteria in all groups except for the group with 1.5% chlorhexidine-xanthan gel (P=0.0054). Conclusion: This modified ex vivo model study showed ultrasonically activated irrigation with sodium hypochlorite had greater effect on intratubular bacteria counts compared with 2-week application of intracanal medications.

The detection of vertical root fractures in post-core restored teeth with cone-beam CT: in vivo and ex vivo.

OBJECTIVES: To compare the accuracy of cone-beam CT ex vivo and in vivo for the detection of artificially created large and small vertical root fractures in extracted teeth restored with post-core. METHODS: Individual metal cast post-cores were fixed in the root canals of 50 extracted single-rooted human teeth. In 30 teeth fractures were created by tapping posts with a hammer. The teeth were sterilised in autoclave and embedded into bite-plates made of silicon impression material. Cone-beam CT scanning was performed ex vivo and in vivo . For the in vivo scanning, teeth in sterile plastic bags were inserted into the mouths of volunteers. Then the teeth were sectioned with low-speed saw and the widths of the VRFs were measured microscopically. The teeth were distributed into 2 groups in accordance with the measured fractures' widths: large (wider than 180-250 µm) and small (80-150 µm). Five observers assessed the presence of vertical root fractures on axial CBCT slices. Sensitivity, specificity, accuracy and inter examiner agreement were calculated. RESULTS: The accuracy of cone-beam CT in vitro for large and small vertical root fractures detection was 0.56 and 0.40 respectively (p = 0.043). The sensitivity values were 0.53 and 0.27 for large and small vertical root fractures, respectively (p = 0.043). The visualisation of fracture lines in vivo was impossible in 90 % of cases, because of low image quality. Inter examiner reliability analysis showed κ values ranging from 0.02 to 0.54. CONCLUSIONS: Fracture width affected the in vitro detectability of vertical root fractures by cone-beam CT in teeth with metal cast post-cores. The detectability of root fractures in vivo was decreased because of low image quality, making the assessment of sound tooth tissue impossible.