OBJECTIVES: The aim of this project is to develop a novel 3D cephalometric analysis using anatomical landmarks that cannot be easily viewed on a planar film but on a CBCT image and study the reliability of these measurements between different examiners. METHODS: Fifty CBCT images of patients with normodivergent, Class I skeletal patterns and without any noticeable craniofacial deformities were screened and included in the study based on the lateral cephalograms generated from CBCT data using the Roth/Jarabak Analysis. Fifteen predetermined landmarks that found to be reliable in another associated study were used to define six planes. Measurements were also completed on a human dry skull to confirm accuracy. Eleven different cephalometric measurements were performed by three operators three times using landmarks and planes in 3D. Descriptive statistics (mean and standard deviation) and intra-class correlation coefficient for intra- and inter-examiner reliability was performed. RESULTS: The measurements showed that the means and standard deviations of all three measurers are: for Mandibular A/P: 14.49mm ±2.26; Mandibular deviation: 1.63mm, ±1.19; Maxilla/Mandibular divergence: 24.51°, ±3.85; Maxillary deviation: 0.94mm ±0.5; Pitch (Mandibular Plane), 50.38° ±2.8; Pitch (Maxillary Plane): 74.66° ±3.53; Roll (Mandibular Plane): 87.66° ±2.38, 0.05; Roll (Maxillary Plane): 87.70° ±1.85; Yaw (Maxillary Plane): 4.41°± 2.11; Yaw (Mandibular): 3.61°± 2.43; Maxillary A/P: 2.96mm ±2.26. An interclass correlation was calculated at a range from 0.53 to 0.95. CONCLUSIONS: The means and standard deviations of the measurements can be used as a reference to study. Amongst the operators, we indicate between moderate and excellent reliability. The highest reliability was with measurement mandibular pitch. Lowest reliability was with measurement mandibular roll.

Introduction: An extensive knowledge of dental root and canal anatomy is essential to clinicians performing endodontic treatment. It is well-known that dental anatomy may be complex and display significant variation. Aim: The aim of the present study was to classify the root number and the root canal configurations of human mandibular first and second molars in a South African sub-population using CBCT. Materials and methods: The study design was a retrospective cross-sectional descriptive study. The sample size included 753 molars. The CBCT images of each individual mandibular first and second molar were evaluated in coronal, sagittal and axial views. Classification of the canal configurations of each root was made using the Vertucci classification system, including the additions proposed by Sert and Bayirli. Classification of root number was described as one, two, three, or four-roots. Results: Root anatomy: Two-rooted configurations were demonstrated in the majority of first and second molars (98.7% and 94%). One- and three-rooted molars were rare with a prevalence ranging from 0.3% to 2.9%. Half of all three-rooted molars presented with two distinct mesial roots. Four-rooted molars were found in second molars only (0.5%). Canal anatomy: The most common canal type in the mesial roots of mandibular first and second molars was Type IV (50% and 38%) followed by Type II (21% and 24%). The most common canal configuration in the distal roots of the first and second molars was Type I (50% and 81%) followed by Type V (20% and 10%). More than two mesial canals in mandibular first and second molars were present in 21% and 17% of the sample. More than two distal canals were demonstrated in first and second molars in 7% and 2% of the sample. C-shaped canal systems were found in 0.5% of first molars and 7.7% of second molars. Sex and age had no correlation to root or canal configurations. Conclusion: More than two mesial canals were found in about one-fifth of the sample. It is important for clinicians to be aware that a number of mandibular molars may present with more intricate anatomy than expected during endodontic treatment and that this may affect treatment outcomes. / Dissertation (MSc (Dent))--University of Pretoria, 2020. / Odontology / MSc (Dent) / Unrestricted

PURPOSE: Although Intra-oral radiographs are foundational for diagnosis and planning treatment in dentistry, the resulting 2-dimensional image varies in interpretation requiring judgement. Cone Beam Computed Tomography provides a more detailed 3-dimensional image that may affect treatment recommendations. This study aimed to determine the basis for CBCT recommendations and its effect on diagnosis and treatment planning. METHODS: The study involved a sample of 45 cases that presented for endodontic treatment, 30 with a CBCT scan on record and 15 without. For phase I, all 45 cases were reviewed by 3 examiners without access to the CBCT scans. Four months later for phase II, the 3 examiners re-analyzed the 30 cases, this time with the associated CBCT. Intra and inter-examiner agreements were recorded and analyzed. Also, the recommendations for CBCT were compared to the AAE/AAOMR Joint Statement. RESULTS: Inter-examiners agreement in phases I and II were 65% and 72% respectively. For endodontic diagnoses, there was 19% change in the pulpal diagnosis category when CBCT was added, while there was 30% change in the apical category. The selections changed in 55% of the cases when determining etiology, and in 49% of the cases when making recommendations. CBCT was recommended 78.8% of the time when the case had a CBCT on record vs. 33% of the time in cases without. CONCLUSION: CBCT has a significant effect in determining endodontic pathology’s etiology and recommending treatment. Further, CBCT is not over prescribed in the endodontic department and the faculty adhere largely to the joint AAE/AAOMR recommendations. / 2021-06-23T00:00:00Z

IINTRODUCTION: This study’s aims were to: 1) evaluate whether or not there was a treat- ment plan change, if CBCT is used; and 2) evaluate if the use of CBCT as diagnostic tool improves the treatment outcome. We hypothesized that 1. the use of CBCT as diagnostic tool changes the treatment plan; and 2. improves the treatment outcome MATERIALS AND METHODS: This was an IRB approved retrospective study of all the conventional re-treatments and surgical RCT performed at Boston University Post-doctoral clinic from 2009 - 2015. Of 10,836 cases completed, 674 cases had a CBCT on file and 31 had a pre- and post-CBCT treatment plan with at least 3 months follow up. Cases with CBCT were matched (2 to 1) with cases without CBCT based on patients’ sex, age, tooth type, diagnosis, procedure performed, and insurance type. Chart notes and treatments were reviewed to identifytreatment plan changes. The investigator evaluated outcome as either Success/Survive/ Failure. Statistical Analyses tested for differences in treatment plan and Success/Survive/ Failure rates at minimum 3 months. RESULT: 31 cases and 49 controls were evaluated. There were no differences in mean age (46) or insurance between cases and controls. In over half of the cases (54.8%) the treatment plan changed when CBCT was used. Cases with CBCT had 32% success rate, 60% sur- vival rate and 8% failure rate at minimum 3 months whereas cases without CBCT had 22.4% success rate, 53.1% survival rate and 24.5% failure rate, p-value = 0.21. CONCLUSION: The use of CBCT as diagnostic tool affected more than half of the treatment plans. While CBCT appeared to improve the treatment outcomes, the difference in this small sample is not statistically significant. Future research will require larger sample sizes to test whether CBCT improves treatment efficacy in endodontics.

Yes / Scaphoid radiography has poor sensitivity for acute fracture detection and often requires repeat delayed imaging. Although magnetic resonance (MR) imaging is considered the gold standard, computed tomography (CT) is often used as an alternative due to ease of access. Cone-Beam CT (CBCT) offers equivalent diagnostic efficacy to Multi Slice CT (MSCT) at reduced dose. We aimed to establish the difference in scattered dose between modalities for scaphoid imaging. Methods: Anatomical regional entrance surface dose measurements were taken at 3 regions on an anthropomorphic torso phantom positioned as a patient to a wrist phantom undergoing scaphoid imaging for three modalities (CBCT, MSCT, four-view projection radiography). Exposure factors were based on audit of clinical exposures. Each dose measurement was repeated three times per anatomical region, modality, exposure setting and projection. Results: Under unpaired T-test CBCT gave significantly lower mean dose at the neck (1.64 vs 18 mGy), chest (2.78 vs 8.01) and abdomen (1.288 vs 2.93) than MSCT (p

No description available.

Cone beam computed tomography (CBCT) is the recommended imaging modality of choice for evaluating previous endodontic treatment (1). The aim of this study was to compare treatment planning decisions made when evaluating previous endodontic treatment to determine if treatment planned and projected prognosis differs when digital radiography is used alone or in combination with CBCT. A retrospective chart review was conducted. Patients for whom a CBCT was taken were included in the study. Twenty-eight patients qualified. Patient’s periapical digital radiographs (Dexis©) were evaluated by 2 calibrated endodontists, a treatment plan was identified and a prognosis was projected. Later the same radiographs were viewed with CBCT scan. The CBCT provided significant information 75% of the time. CBCT provided the only information for an accurate diagnosis 17% of the time. Prognosis changed 38% of the time when CBCT was added. An unfavorable or questionable prognosis changed to favorable 30% of the time.

OBJECTIVES: The objective of this research is to evaluate variation of mandibular arch forms at different heights and to determine if there is any correlation between occlusal arch and sub-gingival arch forms. METHODS: 44 subjects were selected based on the inclusion criteria and their CBCTs then were imported to Mimics software (Materialise NV, Belgium) and traced. Each tooth was sliced midsection at 4 different heights: Occlusal, CEJ, Apex and 5mm apical to the apex. At occlusal level the midpoint of the crown was calculated mesiodistally as well as buccolingually. Subsequently, midpoints between the buccal and lingual plates were located for every tooth between and including the first molars. The points were connected forming 4 splines, which then were exported to Geomorph software (cran.r-project.org, Geomorph package, Dean Adams author, Iowa State 2015) for shape statistical analysis. RESULTS: The variation in the arch form among subjects is significantly smaller in the Occlusal and CEJ level. The variation at apical and basal bone levels are higher than the variation at CEJ and occlusal levels. However, variation between apical and basal bone levels are minimal. CONCLUSIONS: Mandibular dental arch form demonstrate more variation apically. It may be concluded that dental arch form variation should be considered when using standardized arch forms for different patients. The subgingival arch forms cannot be predicted from occlusal arch form. Occlusal arch shape and form may not be an indication of basal bone arch form. More information needed for detection of correlation between occlusal arch and sub-gingival arch forms.

No description available.

Objective: The purpose of this study was to compare the accuracy of cone beam CT (CBCT) imaging with digital orthopantomograms for determining bone quantity in the mandibular ramus. Methods: Twenty-nine cadaveric mandibles marked bilaterally with three fiducial markers were imaged using both CBCT and digital orthopantomography. After sectioning, four cross sectional measurements were made on the specimens and on the CBCT images. Two corresponding linear measurements were made on the orthopantomograms. Statistical analysis was used to compare the CBCT and orthopantomogram measurements with measurements from the anatomic specimens. Results: CBCT measurements were found to significantly differ from those made on the anatomic specimens (P<0.05). Linear measurements from the orthopantomograms varied by 15.9 percent compared to the anatomic specimens. Conclusion: CBCT and orthopantomogram measurements were significantly different from those of the anatomic specimens suggesting inaccuracies in the radiographic technology or a lack of precision in landmark identification.