Relationship between pterygomaxillary fissure morphology and maxillary/mandibular position : A cone beam computed tomography assessment.

PURPOSE: The aim of this study was to investigate the possible correlation between maxillary and mandibular positioning via cephalometric analysis with pterygomaxillary fissure (PMF) morphology using cone beam computed tomography (CBCT). METHODS: In this study, CBCT images from 825 individuals (448 female, 377 male; age range was 18-91 years with this cohort) were analyzed; PMF length and width were measured. Three-dimensional cephalometric analysis was also performed using cephalometric analysis software. The landmarks and measurements in relation to maxillary and mandibular positions were identified and performed for the cephalometric analysis. Analysis of variance (ANOVA) was used for comparison of the parameters, while the Bonferroni test was used for multiple comparisons. Pearson's test was also used to assess the correlations between the parameters. RESULTS: The results showed that males had significantly larger PMF length (p < 0.001) and width (p < 0.001) compared to females. The mean PMF length was 17.7 mm (standard deviation [SD] 3.2 mm) for right and 17.7 mm (SD 3.3 mm) for left but were not significantly different (p > 0.05). In terms of the cephalometric measurements, a significant correlation was found between upper central incisor (U1toAperp2D) and posterior facial height (PostFaceHtSGo2D) and PMF length, while correlations were found between PMF width and several cephalometric parameters such as lower lip (LwLiptoEPln2D and LwLiptoHLine2D) and occlusal plane (OPtoFHAng2D) (p < 0.05). CONCLUSION: A significant relationship was observed between PMF morphology and the position of the maxilla or mandible. PMF lengths and widths were larger in males than females. Posteroanterior maxillary and mandibular lengths and posterior facial height are associated with PMF length and width.

An anatomical variant: evaluation of accessory canals of the canalis sinuosus using cone beam computed tomography.

BACKGROUND: The anatomical variation of the anterior superior alveolar nerve described as canalis sinuosus (CS) is a less known structure of anterior maxilla. Due to the fact that it contains anterior superior alveolar nerve as well as veins and arteries, exact localisation of this structure will allow surgeons to avoid complications. Hence, the aim of this study was to verify the presence, reveal the frequency and characteristics of accessory canals of CS. MATERIALS AND METHODS: This study was based on retrospective evaluation of cone beam computed tomography (CBCT) scans. A total of 1460 CBCT images were analysed and collected data were noted. The following parameters were recorded: age, sex, presence or absence of CS, location in relation to the adjacent teeth and impaction of canine teeth. RESULTS: A total of 6668 accessory canals were found in 1460 CBCT images. Of these, 672 (46.0%) were from female patients, and 788 (54.0%) were from male patients. 1034 (70.8%) of 1460 images had at least one accessory canal of CS. Maxillary intercentral region is the area where accessory canals were seen most frequently (n = 653, 44.72%). CONCLUSIONS: Canalis sinuosus is a bony canal which is incidentally found and less known structure of anterior portion of maxilla. Knowing the accessory canals deriving from this structure will allow surgeons to avoid complications and non-integration after dental implant procedures. Conventional imaging modalities have limited value in detecting this neurovascular structures. Therefore CBCT may have an important role for accurate diagnosis to reveal anatomical variations.

Morphological assessment of the stylohyoid complex variations with cone beam computed tomography in a Turkish population.

BACKGROUND: The aim of this investigation was to evaluate the length, thickness, sagittal and transverse angulations and the morphological variations of the stylohyoid complex (SHC), to assess their probable associations with age and gender, and to investigate the prevalence of it in a wide range of a Turkish sub-population by using cone beam computed tomography (CBCT). MATERIALS AND METHODS: The CBCT images of the 1000 patients were evaluated retrospectively. The length, thickness, sagittal and transverse angulations, morphological variations and ossification degrees of SHC were evaluated on multiplanar reconstructions (MPR) adnd three-dimensional (3D) volume rendering (3DVR) images. The data were analysed statistically by using nonparametric tests, Pearson's correlation coefficient, Student's t test, c2 test and one-way ANOVA. Statistical significance was considered at p < 0.05. RESULTS: It was determined that 684 (34.2%) of all 2000 SHCs were elongated (> 35 mm). The mean sagittal angle value was measured to be 72.24° and the mean transverse angle value was 70.81°. Scalariform shape, elongated type and nodular calcification pattern have the highest mean age values between the morphological groups, respectively. Calcified outline was the most prevalent calcification pattern in males. There was no correlation between length and the calcification pattern groups while scalariform shape and pseudoarticular type were the longest variations. CONCLUSIONS: We observed that as the anterior sagittal angle gets wider, SHC tends to get longer. The most observed morphological variations were linear shape, elongated type and calcified outline pattern. Detailed studies on the classification will contribute to the literature. (Folia Morphol 2018; 77, 1: 79-89).

Comparison of the influence of FOV sizes and different voxel resolutions for the assessment of periodontal defects.

OBJECTIVES: This study assessed the influence of different voxel resolutions of two different CBCT units on the in vitro detection of periodontal defects. METHODS: The study used 12 dry skulls with a maxilla and a mandible. Artificial defects (dehiscence, tunnel, fenestration) were separately created on the anterior, premolar and molar teeth using burrs. A total of 14 dehiscences, 13 fenestrations, 8 tunnels and 16 non-defect controls were used in the study. Images were obtained from two different CBCT units in six voxel sizes (voxel size: 0.080, 0.100, 0.125, 0.150, 0.160 and 0.200 mm3). Kappa coefficients were calculated to assess both intra- and interobserver agreements for each image set. RESULTS: Overall intraobserver kappa coefficients ranged between 0.978 and 0.973 for the 0.080-mm3 images and between 0.751 and 0.737 for the 0.160-mm3 images, suggesting notably high intraobserver agreement for detecting periodontal defects. CBCT performed significantly better at detecting fenestrations (p<0.05) than tunnel and dehiscence defects. No statistically significant difference was found between the detection of dehiscence and tunnel defects (p>0.05). CONCLUSIONS: A voxel size of 0.150 mm3 was identified as the cut-off point for overall detection of periodontal defects. CBCT should be considered the most reliable imaging modality for the diagnosis of periodontal defects.

A retrospective analysis of prevalence and characteristics of pre-eruptive intracoronal resorption in unerupted teeth of the permanent dentition: a multicentre study.

AIM: This multicentred study aimed to investigate the prevalence of pre-eruptive intracoronal resorption (PIR) in unerupted teeth of the permanent dentition using a large sample of panoramic radiographs of a Turkish population. METHODOLOGY: Records of 28 612 patients from three cities in the different regions of Turkey were screened retrospectively in this multicentred study. Patient records and panoramic radiographs were evaluated by three oral and maxillofacial radiologists in the sites. The following data were recorded: age, gender, number of unerupted teeth, number of teeth showing intracoronal resorption, affected tooth type and number of intracoronal resorptions in each case. RESULTS: Overall, 5554 patients had at least one unerupted tooth in 28 612 patients, with a prevalence of 19.4%. Of the 5554 patients screened, 2267 were female and 3287 were male. Intracoronal resorption was observed in 40 of 5554 subjects, with a frequency of 0.7%. The mean age of the patients was 35.9 years. CONCLUSION: Pre-eruptive intracoronal resorption defects occurred in 40 subjects. Increased awareness and careful radiographic examination of unerupted teeth may improve early detection and treatment of PIR defects.

Accuracy of CBCT images in the assessment of buccal marginal alveolar peri-implant defects: effect of field of view.

OBJECTIVES: To investigate the reliability and accuracy of cone beam CT (CBCT) images obtained at different fields of view in detecting and quantifying simulated buccal marginal alveolar peri-implant defects. METHODS: Simulated buccal defects were prepared in 69 implants inserted into cadaver mandibles. CBCT images at three different fields of view were acquired: 40 × 40, 60 × 60 and 100 × 100 mm. The presence or absence of defects was assessed on three sets of images using a five-point scale by three observers. Observers also measured the depth, width and volume of defects on CBCT images, which were compared with physical measurements. The kappa value was calculated to assess intra- and interobserver agreement. Six-way repeated analysis of variance was used to evaluate treatment effects on the diagnosis. Pairwise comparisons of median true-positive and true-negative rates were calculated by the χ² test. Pearson's correlation coefficient was used to determine the relationship between measurements. Significance level was set as p < 0.05. RESULTS: All observers had excellent intra-observer agreement. Defect status (p < 0.001) and defect size (p < 0.001) factors were statistically significant. Pairwise interactions were found between defect status and defect size (p = 0.001). No differences between median true-positive or true-negative values were found between CBCT field of views (p > 0.05). Significant correlations were found between physical and CBCT measurements (p < 0.001). CONCLUSIONS: All CBCT images performed similarly for the detection of simulated buccal marginal alveolar peri-implant defects. Depth, width and volume measurements of the defects from various CBCT images correlated highly with physical measurements.

Radiographic detection of artificially created horizontal root fracture using different cone beam CT units with small fields of view.

OBJECTIVES: To compare limited cone beam computerized tomography (CBCT) units with different field of views (FOVs) and voxel sizes in detecting artificially created horizontal root fracture (HRF) in extracted human teeth. METHODS: Artificial HRF was created in the horizontal plane in 40 teeth. Another 40 intact teeth served as a control group. 80 teeth were placed in the respective maxillary anterior sockets of a human dry skull in groups. Six image sets were obtained: (1) Accuitomo 170, 40 × 40 mm FOV (0.080 mm(3)); (2) Accuitomo 170, 60 × 60 mm FOV (0.125 mm(3)); (3) Kodak 9000, 50 × 37 mm FOV (0.076 mm(3)); (4) Kodak 9000, 50 × 37 mm FOV (0.100 mm(3)); (5) Vatech Pax-Duo3D 50 × 50 mm FOV (0.080 mm(3)) and (6) Vatech Pax-Duo3D 85 × 85 mm FOV (0.120 mm(3)). Images were evaluated twice by five observers. Kappa values were calculated for observer agreement. Areas under the receiver operating characteristic (ROC) curves (Az values) were calculated, and the Az values for each image type were compared using t-tests (α = 0.05). RESULTS: Intraobserver kappa coefficients ranged from 0.81 to 0.95 for the Accuitomo 170 images, from 0.80 to 0.92 for the Kodak 9000 images and from 0.76 to 0.95 for Vatech PanX-Duo3D. The Az values for different image types and observers ranged from 0.93 to 0.97 for Accuitomo 170 images, from 0.93 to 0.98 for Kodak 9000 images and from 0.93 to 0.97 for the Vatech PanX-Duo3D images. No statistically significant differences (p > 0.05) were found between the Az values. CONCLUSIONS: Limited CBCT units performed similarly in detecting simulated HRF.

Diagnostic accuracy of different imaging modalities in detection of proximal caries.

OBJECTIVE: The purpose of this study was to assess the in vitro diagnostic ability of visual inspection, film, charge-coupled device (CCD) sensor, photostimulable phosphor (PSP) sensor and cone beam CT in the detection of proximal caries in posterior teeth compared with the histological gold standard. METHODS: Visual inspection, film, CCD, PSP and cone beam CT images were used to detect proximal caries in the mesial and distal surfaces of 138 teeth (276 surfaces). Visual inspection and evaluation of all intraoral digital and conventional radiographs and cone beam CT images were performed twice by three oral radiologists. Weighted kappa coefficients were calculated to assess intra- and interobserver agreement for each image set, and scores were compared with the histological gold standard using receiver operating characteristic (ROC) analysis to evaluate diagnostic ability. RESULTS: Intraobserver kappa coefficients calculated for each observer for each method of detecting caries ranged from 0.739 to 0.928. Strong interobserver agreement ranging from 0.631 to 0.811 was found for all detection methods. The highest Az values for all three observers were obtained with the cone beam CT images; however, differences between detection methods were not statistically significant (P > 0.05). CONCLUSION: Visual inspection, film, CCD, PSP plates and cone beam CT performed similarly in the detection of proximal caries.

Dentin hypersensitivity: a randomized clinical comparison of three different agents in a short-term treatment period.

OBJECTIVE: Dentin hypersensitivity, or what patients may describe as "sensitive teeth," is defined as a short, sharp pain arising from exposed dentin in response to thermal, evaporative, tactile, electrical, osmotic or chemical stimuli. It is widely accepted that dentin hypersensitivity is an uncomfortable condition that also affects function and quality of life. This study determines the differences in efficiency of three desensitizing products when compared with a placebo. METHODS: A randomized controlled clinical trial was conducted to compare three different professional dentin desensitizer agents in 52 patients. The age and sex of the patients was recorded. Gluma Desensitizer (Heraeus Kulzer), UltraEZ (Ultradent Products, Inc) and Duraphat (Colgate Oral Pharmaceuticals, Inc, New York, NY, USA) were used as desensitizer agents and distilled water was used as the placebo. The baseline measurement of the dentin hypersensitivity was made by using a visual analog scale (VAS). Twenty-four hours and seven days after application of the desensitizer agents and placebo, a new VAS analysis was conducted for patients' sensitivity level. The desensitizer agents were compared in terms of mean values, and ANOVA was used for testing differences among the groups (p<0.05). RESULTS: The results showed that the mean pain scores of the placebo group were significantly higher than that of the study groups (p<0.05). The VAS analysis revealed a significant decrease in dentin hypersensitivity over time with the use of agents (p<0.05). No statistically significant difference was found among the three desensitizing agents (p>0.05). CONCLUSIONS: These three desensitizing agents, which contain different active ingredients, were effective in relieving dentin hypersensitivity. However, no superiority was found in dentin sensitivity relief among the agents.