PURPOSE: The purpose of this clinical study was to determine the prevalence of type of posterior mandibular ridge morphology in a Malaysian population and to evaluate the buccolingual width of the alveolar ridge (Wb and Wc); alveolar ridge height (Vcb); and concavity angle, length, and depth for both left and right first and second molars in different age groups and sexes by using cone beam computed tomography (CBCT).
MATERIAL AND METHODS: Bilateral posterior mandibular lingual concavities at the first and second molars were retrospectively studied in cross-sectional views of 150 CBCT scans (n=600 sites evaluated). The sample size was calculated at a power of 80%, confidence interval of 95%, and margin of error of .05. The buccolingual width from the base and crest of the ridge and the ridge height were measured to determine the type of ridge. For the U-shaped ridge, the concavity angle, length, and depth were assessed. The independent t test was used to compare mean values of CBCT measurements between sexes and tooth type, while the ANOVA and Pearson chi-squared test were used to determine the correlations with age groups and types of ridge morphology, respectively. To compare the left and right readings for first and second molars in the same patient, the paired t test was performed (α=.05 for all tests).
RESULTS: The Pearson correlation showed a strong agreement between the 2 examiners with an interobserver reliability of 87.3%. Significant difference was noted in all dimensional measurements when comparing right and left first and second molars (P
MATERIALS AND METHODS: In this study, 20 implant sites in patients were selected. Ridge mapping was done through a vacuum press template at three buccal (B1, B2, B3), three lingual (L1, L2, L3), and one crestal (C) points for each implant site. Readings were transferred onto the cast, and surgical guides were fabricated for implant placement. Postoperative cone beam computerized tomography (CBCT) was done to assess planned and achieved implant position. Comparison was done between soft tissue depths and implant distance from the crest of alveolar bone determined by the ridge mapping technique with measurements done on CBCT. The points used for ridge mapping were used as the reference for measurements. The data were analyzed using paired t test. p < 0.05 was considered to be statistically significant.
RESULTS: On comparing the mean values of soft tissue depths from the ridge mapping and CBCT data, insignificant differences were found at B1, B2, L1, L2, L3, and C, but significant differences were found at B3. On comparing the implant distances from alveolar bone from both the data, insignificant differences were found at B, B2, B3, L1, L2, and L3 and significant difference was found at the crest in the mean values.
CONCLUSION: Under the limitations of the above study, it can be concluded that a simple chairside procedure like ridge mapping can be used as an effective way for guided implant placement in sufficient available alveolar bone.
MATERIALS AND METHODS: This parallel, single-blinded, randomised controlled trial (RCT) consisted of 22 periodontitis patients who had molar with advanced furcation involvement (FI). All patients followed the same inclusion criteria and were treated following the same protocol, except for radiographic evaluation (CBCT vs. periapical). This study proposed and evaluated five parameters that represent the extent and severity of furcation defects in molars teeth, including CEJ-BD (clinical attachment loss), BL-H (depth), BL-V (height), RT (root trunk), and FW (width).
RESULTS: There were no statistically significant differences between CBCT and intrasurgical linear measurements for any clinical parameter (p > 0.05). However, there were statistically significant differences in BL-V measurements (p
METHODS: A systematic review was undertaken following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was performed by 2 independent reviewers using a customized search strategy in major Endodontic journals through Scopus until November 2019. Studies investigating root and canal anatomy were included. The selected publications were divided into 7 categories according to the study design: micro-computed tomography (microCT) and cone-beam computed tomography (CBCT) experimental studies (extracted teeth), CBCT and 2D clinical studies, CBCT and 2D case reports in addition to others (i.e. staining and clearing method and root sectioning). The selected studies were evaluated according to three domains: 1) Criteria for study sample selection; 2) Criteria for methodological procedures and 3) Criteria for detection and evaluation.
RESULTS: After the removal of duplicated and irrelevant papers, 137 articles were included. Results showed that microCT studies reported accurately the tooth type, number of teeth, classifications used, qualitative and/or quantitative analysis (if required) and the evaluation process. However, sample size calculation, calibration, and reproducibility were not reported in the majority of microCT studies. CBCT clinical studies presented information for the type of study, inclusion/exclusion criteria, number of patients, tooth type, and number of teeth. However, the majority did not report sample size calculation and calibration of examiners. Radiographic exposure descriptions and classifications used were not reported adequately in CBCT and 2D case reports. Sample size calculation, calibration and reproducibility were not reported in staining and clearing method.
CONCLUSION: Despite accurate presentation of certain items, there is considerable inconsistent reporting of root and canal morphology regardless of the type of study and experimental procedure used. The PROUD checklist protocol presented in this systematic review aims to provide an accurate description of root canal anatomy in experimental, clinical, and case report publications.
METHODS: Twenty volumes of interests consisting of six anterior and fourteen posterior edentulous regions were obtained from human mandibular cadavers. A CBCT system with a resolution of 80 µm (3D Accuitomo 170, J. Morita, Kyoto, Japan) and a µCT system with a resolution of 35 µm (SkyScan 1173, Kontich, Belgium) were used to scan the mandibles. Three structural parameters namely, trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp) were analysed using CTAn software (v 1.11, SkyScan, Kontich, Belgium). For each system, the measurements obtained from anterior and posterior regions were tested using independent sample t-test. Subsequently, all measurements between systems were tested using paired t-test.
RESULTS: In CBCT, all parameters of the anterior and posterior mandible showed no significant differences (p > 0.05). However, µCT showed a significant different of Tb.Th (p = 0.023) between anterior and posterior region. Regardless of regions, the measurements obtained using both imaging systems were significantly different (p ≤ 0.021) for Tb.Th and Tb.N.
CONCLUSIONS: The current study demonstrated that only the variation of Tb.Th between anterior and posterior edentulous region of mandible can be detected using µCT. In addition, CBCT is less feasible than µCT in assessing trabecular bone microstructures at both regions.
METHODOLOGY: A total of 700 maxillary premolars were examined using CBCT in an Egyptian subpopulation. The number of roots was identified, and root canal configurations were classified according to Vertucci's classification and a new system for classifying root and canal morphology. In addition, the position where roots bifurcated and the levels where canals merged or diverged were identified. Fisher's exact test and independent t-test were used for statistical analysis, and the level of significance was set at 0.05 (P = 0.05).
RESULTS: More than half of maxillary first premolars were double-rooted, and the majority of maxillary second premolars were single-rooted (P
Aim: This study investigated the prevalence and location of second mesiobuccal (MB2) canal in mesiobuccal root of maxillary first molar using cone beam computed tomography (CBCT) images in an Indian population.
Materials and methods: CBCT images of 598 three rooted maxillary first molars were studied. In each CBCT image, the floor of pulp chamber was located and advanced by 2 mm to standardize the observation for MB2 canal. Its location was determined in relation to mesiobuccal (MB1) and palatal (P) canal.
Statistical analysis: The data was analysed using descriptive statistics. The presence of MB2 canal was correlated with age, gender and tooth position using Chi square test.
Results: The prevalence of MB2 canal in three rooted maxillary first molar was 61.9%. It was seen that the prevalence of MB2 was highest in 20-40years age group (67.4%) followed by > 40 years (57.5%) and lowest in <20 years (50.6%) and the difference was statistically significant (p = 0.005). It is located mesiopalatally; 2.5 mm ± 0.6 mm palatally and 1.0 ± 0.4mmmesially to the MB1 canal or present directly on the line joining the MB1 and palatal canal.
Conclusion: There is a high probability of finding MB2 canal in Indian patients. The access cavity must be modified from a triangular shape to rhomboid shape. Troughingmesiopaltally (about 2.5 mm palatally and 1 mm mesially) from MB1 to a depth of about 2 mm from the floor of pulp chamber may be necessary for locating MB2 canal.
Method: Maxillary CBCT images of two-hundred-and-fifty-seven consecutive patients (163 men, 94 women, mean age 42 years) were analyzed. Samples were later divided into dentate (n = 142) and posteriorly edentulous (n = 115) jaws. Using both alveolar ridge and tooth location as reference points, the distance and diameter of IA were assessed.
Result: The IA was seen in 63.7% of all sinuses with 68.2% in dentate and 62.4% in edentulous. Mean distance and diameter of IA across the posterior tooth locations were 17.9 ± 3.0 mm and 1.4 ± 0.5 mm (dentate) and 15.1 ± 3.0 mm and 1.0 ± 0.5 mm (posteriorly edentulous), respectively. In each sample, there were no significant differences in distance-alveolar ridge and no significant correlations in diameter-tooth location. A statistically significant Pearson coefficient correlation between diameter and distance in dentate state was observed (r = -0.6).
Conclusion: This study reveals that dentate maxillary jaws present larger diameters as compared to posteriorly edentulous jaws, although the IA course remains the same. As these canal structures contain neurovascular bundles with diameters that may be large enough to cause clinically substantial complications, a thorough pre-surgical planning is therefore highly advisable.
Methods: Retrospective analysis of 100 CBCT scans (n = 200) was performed on both sides of the mandible. Cross-sectional and panoramic images were reconstructed. The length of the MIC and the horizontal distances between the MIC and the buccal and the lingual cortical plates were measured at the three different points (starting, mid-, end points). Independent samples t-test and one-way ANOVA test were used to analyse the variation in the length and course of the MIC in gender, age, dental status and Malaysian races.
Results: The mean length of the MIC was 11.31 ± 2.65 mm, with the Malays having the longest MIC, followed by the Chinese and the Indians (p
METHODS: Five sectioned maxilla of adult Dorper male sheep were scanned using a CBCT system with a resolution of 76 μm3 (Kodak 9000). The CBCT images were reconstructed using different reconstruction parameters and analysed. The effect of reconstruction voxel size (76, 100 and 200 μm3) and threshold values (±15% from the global threshold value) on trabecular bone microstructure measurement was assessed using image analysis software (CT analyser version 1.15).
RESULTS: There was no significant difference in trabecular bone microstructure measurement between the reconstruction voxel sizes, but a significant difference (Tb.N = 0.03, Tb.Sp = 0.04, Tb.Th = 0.01, BV/TV = 0.00) was apparent when the global threshold value was decreased by 15%.
CONCLUSIONS: Trabecular bone microstructure measurements are not compromised by changing the CBCT reconstruction voxel size. However, measurements can be affected when applying a threshold value of less than 15% of the recommended global value.
METHODS: Five single maxillary premolar extraction sockets received PRF-CS grafts and five single maxillary premolar sockets received PRF-X grafts. Linear (horizontal and vertical) measurements were accomplished using Cone Beam Computed Tomography (CBCT) images and volumetric changes were assessed using MIMICS software. Soft tissue level changes were measured using Stonecast models. All measurements were recorded at baseline (before extraction) and at 5-months post-extraction.
RESULTS: Significant reduction in vertical and horizontal dimensions were observed in both groups except for distal bone height (DBH = 0.44 ± 0.45 mm, p = 0.09) and palatal bone height (PBH = 0.39 ± 0.34 mm, p = 0.06) in PRF-X group. PRF-CS group demonstrated mean horizontal shrinkage of 1.27 ± 0.82 mm (p = 0.02), when compared with PRF-X group (1.40 ± 0.85 mm, p = 0.02). Vertical resorption for mesial bone height (MBH = 0.56 ± 0.25 mm, p = 0.008), buccal bone height (BBH = 1.62 ± 0.91 mm, p = 0.01) and palatal bone height (PBH = 1.39 ± 0.87 mm, p = 0.02) in PRF-CS group was more than resorption in PRF-X group (MBH = 0.28 ± 0.14 mm, p = 0.01, BBH = 0.63 ± 0.39 mm, p = 0.02 and PBH = 0.39 ± 0.34 mm, p = 0.06). Volumetric bone resorption was significant within both groups (PRF-CS = 168.33 ± 63.68 mm3, p = 0.004; PRF-X = 102.88 ± 32.93 mm3, p = 0.002), though not significant (p = 0.08) when compared between groups. In PRF-X group, the distal soft tissue level (DSH = 1.00 ± 0.50 mm, p = 0.03) demonstrated almost 2 times more reduction when compared with PRF-CS group (DSH = 1.00 ± 1.00 mm, 0.08). The reduction of the buccal soft tissue level was pronounced in PRF-CS group (BSH = 2.00 ± 2.00 mm, p = 0.06) when compared with PRF-X group (BSH = 1.00 ± 1.50 mm, p = 0.05).
CONCLUSIONS: PRF-CS grafted sites showed no significant difference with PRF-X grafted sites in linear and volumetric dimensional changes and might show clinical benefits for socket augmentation. The study is officially registered with ClinicalTrials.gov Registration (NCT03851289).
OBJECTIVES: The aim of the study was to evaluate the deviation of implant placement performed with a surgical guide fabricated by means of the rapid prototyping technique (the PolyJet™ technology).
MATERIAL AND METHODS: Twenty sheep mandibles were used in the study. Pre-surgical cone-beam computed tomography (CBCT) scans were acquired for the mandibles by using the Kodak 9000 3D cone-beam system. Two implants with dimensions of 4 mm in diameter and 10 mm in length were virtually planned on the 3D models of each mandible by using the Mimics software, v. 16.0. Twenty surgical guides were designed and printed using the PolyJet technology. A total of 40 implants were placed using the surgical guides, 1 on each side of the mandible (2 implants per mandible). The post-surgical CBCT scans of the mandibles were performed and superimposed on the pre-surgical CBCT scans. The amount of deviation between the virtually planned placement and the actual implant placement was measured, and a descriptive analysis was done.
RESULTS: The results showed that the mean deviation at the implant coronal position was 1.82 ±0.74 mm, the mean deviation at the implant apex was 1.54 ±0.88 mm, the mean depth deviation was 0.44 ±0.32 mm, and the mean angular deviation was 3.01 ±1.98°.
CONCLUSIONS: The deviation of dental implant placement performed with a 3D-printed surgical guide (the PolyJet technology) is within the acceptable 2-millimeter limit reported in the literature.