Cross-sectional Cone-beam Computed Tomography Images Research Articles

The Effect of General Bone Mineral Density on the Quantity and Quality of the Edentulous Mandible: A Cross-Sectional Clinical Study

Osteoporosis is a disease which is characterized by a decrease in general bone mineral density (BMD), resulting in decreased bone strength and an increased risk of bone fractures. The effect of reduced BMD on the jawbones is still not fully understood. The purpose of the study was to evaluate the impact of BMD on the quality and quantity of the edentulous mandible. The present study included 127 edentulous postmenopausal women who underwent cone beam computed tomography (CBCT) examinations. BMD measurements of the lumbar spine and femoral necks were performed by dual-energy X-ray absorptiometry. In the cross-sectional CBCT images, three different areas of the mandible (lateral incisor, first premolar, and first molar) were selected. The complete mandibular, trabecular, and cortical bone volumes were measured. All measurements were performed on the total mandibular area, and the basal and alveolar parts of the mandible. The volume of the cortical bone was reduced for females with reduced BMD in the lateral incisor and first premolar regions, both in the total mandibular area and in the basal part of the mandible. The trabecular bone volume statistically significantly increased when the BMD decreased in the complete mandibular area and the basal part of the mandible (linear regression). The total bone volume significantly decreased with a decrease in BMD in the basal part of the mandible. Reduced BMD has a negative effect on the quantity and quality of bone in the basal part of the edentulous mandible.

Diagnostic performance of stitched and non-stitched cross-sectional cone-beam computed tomography images of a non-displaced fracture of ovine mandibular bone.

This study assessed the diagnostic performance of stitched and non-stitched cross-sectional cone-beam computed tomography (CBCT) images of non-displaced ovine mandibular fractures. In this ex vivo study, non-displaced fractures were artificially created in 10 ovine mandibles (20 hemi-mandibles) using a hammer. The control group comprised 8 hemi-mandibles. The non-displaced fracture lines were oblique or vertical, <0.5 mm wide, 10-20 mm long, and only in the buccal or lingual cortex. Fracture lines in the ramus and posterior mandible were created to be at the interface or borders of the 2 stitched images. CBCT images were obtained from the specimens with an 80 mm × 80 mm field of view before and after fracture induction. OnDemand software (Cybermed, Seoul, Korea) was used for stitching the CBCT images. Four observers evaluated 56 (28 stitched and 28 non-stitched) images to detect fracture lines. The diagnostic performance of stitched and non-stitched images was assessed by calculating the area under the receiver operating characteristic curve (AUC). Sensitivity and specificity values were also calculated (alpha=0.05). The AUC was calculated to be 0.862 and 0.825 for the stitched and non-stitched images, respectively (P=0.747). The sensitivity and specificity were 90% and 75% for the non-stitched images and 85% and 87% for the stitched images, respectively. The inter-observer reliability was shown by a Fleiss kappa coefficient of 0.79, indicating good agreement. No significant difference was found in the diagnostic performance of stitched and non-stitched cross-sectional CBCT images of non-displaced fractures of the ovine mandible.

Comparison of Trabecular Bone in Impacted and Normal Erupted Unilateral Maxillary Canine Teeth Using Cone-Beam Computed Tomography in Patients Scheduled for Orthodontic Treatment at the Universitas Airlangga Dental and Oral Hospital

Background. Cone-beam computed tomography is being utilized in more clinical contexts and determining bone density with this method is becoming more important. Dentists, particularly dentomaxillofacial radiologists, orthodontists, and oral surgeons, must have a solid understanding of gray value. The gray values acquired from conebeam computed tomography images are used to assess dental implant bone density, diagnose dental ankylosis, and diagnose and differentiate pathological lesions. Objective. To determine the difference in the gray value of the trabecular bone in the impacted and normal erupted maxillary canine teeth using cone computed tomography. Methods. We retrospectively evaluated the cone-beam computed tomography images of patients scheduled for orthodontic treatment at the Universitas Airlangga Dental and Oral Hospital. On cross-sectional cone-beam computed tomography images, the region of interest determination of 5 mm2 in the area was placed in the trabecular bone and the gray value measurements were collected using Digital Imaging and Communications in Medicine (OnDemand3D™) dental software. The images were categorized by type of impacted canine teeth after assessing the gray values of all the teeth. Using images on the mesial, distal, buccal, and palatal areas, gray values of impacted and non-impacted teeth were compared. We used the SPSS 24 software. Results. From a total of 13 patient radiographs, we found types I (6/13), II (6/13), and VII (1/13). The mean pixel values of impacted maxillary unilateral canine teeth were 1972.92 (mesial), 2016.55 (distal), 1990.66 (buccal), and 1904.39 (palatal). The mean pixel values of normal erupted maxillary canines were 1754.93 (mesial), 1710.53 (distal), 1852.94 (buccal), and 1674.49 (palatal). There were significant differences between impacted and normal erupted maxillary canines: mesial (P = 0.018), distal (P = 0.000), buccal (P = 0.003), and palatal (P = 0.036). Conclusion. There were statistically significant differences between affected and unaffected gray values in the canines in FOV size 51 × 55 mm. However, no statistically significant differences were found in the gray values in trabecular bone of unilateral maxillary impacted canines and normal erupted canines on the mesial, distal, buccal, and palatal sides.

Investigation the anterior mandibular lingual concavity by using cone-beam computed tomography.

In the presence of lingual concavity in the mandible, the cortical perforation and consequently the life-threatening intraoral haemorrhages obstructing the upper respiratory tract may be seen during the surgical intervention. The present study was aimed to determine the prevalence of lingual concavity in the interforaminal region and its relationship with gender and dentate status. The images of 106 patients who underwent cone-beam computed tomography (CBCT) between 2016 and 2017 in Department of Dental and Maxillofacial Radiology Department of Faculty of Dentistry of Ondokuz Mayıs University were retrospectively examined. The images were obtained using a Galileos device (98 kVp, 15-30 mA). The bone height and width in interforaminal region and the frequency of lingual concavity were analysed. Of patients involved in the present study, 42.5% were male and 57.5% were female After the examinations performed, the bone was morphologically classified into four classes as type I lingual concavity, type II inclined to lingual, type III enlarging towards labiolingual and type IV buccal concavity. Type III (77.9%) was the most common type in the anterior region, followed by type II (16.5%), type I (4.7%) and type IV (0.9%). The lingual concavity angle was 76.5 ± 3.69º and the concavity depth was 2.09 ± 0.34 mm. The lingual concavity can be detected by using the cross-sectional CBCT images and the complications related with lingual cortical perforation can be prevented.

A cone-beam computed tomographic assessment of the proximity of the maxillary canine and posterior teeth to the maxillary sinus floor: Lessons from 4778 roots

When tooth roots protrude into the maxillary sinus, apical root resorption and tipping may occur during horizontal tooth movement across the sinus floor. Three-dimensional cone-beam computed tomography (CBCT) images may provide detailed information without distortion and overlap. We evaluated the relationships between the maxillary tooth root apices and the maxillary sinus floor using CBCT. We evaluated 4778 roots from 76 men (aged 27.6±10.4 [mean±standard deviation] years; range, 18-69years), and 225 women (aged 30.4±12.0years; range, 18-68years). The positional relationships between the maxillary tooth root apices, including the canine, premolar (first and/or second), and molar (first and/or second), and the inferior wall of the maxillary sinus were comprehensively evaluated on 2 cross-sectional CBCT images (ie, the sagittal and coronal planes). These distances were measured in both images simultaneously. The sagittal plane distances were significantly larger than coronal plane distances, except for the distobuccal root of the first molar. Pearson correlation test revealed a significant negative correlation between the distance and the patient's age. Our study provides valuable information for planning orthodontic tooth movement through the maxillary sinus, which may help to predict the occurrence and severity of root resorption.

Radiographic evaluation of the anatomical relationship of maxillary sinus floor with maxillary posterior teeth apices in the population of Al-Qassim, Saudi Arabia, using cone beam computed tomography

Background & objectiveIn current clinical dental practice radiographic imaging plays a major role in exploring the relationship between the maxillary sinus floor (MSF) and maxillary posterior teeth root apices, especially when there is an involvement of pathology in the periapical area that may lead to infectious, inflammatory or traumatic changes in the maxillary sinus (MS). It is also essential for exact implant placement, and therapeutic and surgical plans. The prevalence of different forms of anatomic relationship of the MSF to posterior root apices from one population to another is large. Hence the current research was conceived to evaluate the horizontal and vertical relationship forms of posterior root apices to the MSF in the Al-Qassim population of Saudi Arabia using Cone Beam Computed Tomography (CBCT). Materials and methodsTo conduct the study, a total of 200 patients' data (100 male and 100 female) were taken from the archives. The linear distances of the root apices to the MSF were measured for maxillary posterior teeth. On cross-sectional CBCT images, the Kwak et al. criteria were used to assess the horizontal and vertical relationships between the root apices of maxillary posterior teeth and the MSF. ResultsThe mean distance between the apices of the maxillary second premolar ranged from 4.63 mm to 6.49 mm. The mean value of the distance between the apices of the posterior teeth and the MSF had a range of 0.68 ± 0.39 mm on the disto-buccal root (DBR) of the maxillary right second molar to 3.93 ± 1.26 mm on the palatal root (PR) of the maxillary left first molar. A similar result was observed in the maxillary second molar DBR in the male group (0.68 ± 1.17 mm) and the female group (0.69 ± 1.17 mm). The most frequently observed vertical relations were type 2 and type 2H horizontal relations. ConclusionThis study concludes that maxillary molar roots show greater proximity with the MSF when compared with premolars, and that the type 2 vertical and type 2H horizontal distribution suggests that the anatomy of each tooth and the maxillary sinus floor should be evaluated by CBCT prior to treatment planning.

Facial alveolar bone alterations and gray value changes based on cone beam computed tomography around maxillary anterior implants: A clinical retrospective study of 1-3years.

The purpose of this cone beam computed tomography (CBCT) study was to describe facial alveolar bone alterations and gray value (GV) changes around implants in aesthetic anterior maxilla with simultaneous guided bone regeneration (GBR) and to investigate potential influence of factors related to vertical alveolar bone stability, such as particle sizes of the deproteinized bovine bone mineral (DBBM) used. A retrospective study design was adopted. Four facio-palatal cross-sectional CBCT images of 166 implants from 124 patients who had maxillary anterior implants were obtained. Measurements of the vertical facial alveolar bone level (VFBL), horizontal facial alveolar bone thickness (HFBT), and GV were identified of 1-3years. Then, correlation coefficients for those parameters were calculated. Finally, linear mixed models were established to investigate potential factors influencing vertical alveolar bone resorption. Facial alveolar bone underwent fast bone modeling and remodeling during the first 6months, with decreases of 1.00±1.19 and 0.74±0.86mm in VFBL and HFBT in implant shoulder, respectively, and there was positive and significant correlation between the alterations in VFBL and HFBT1 (rs =.516, p=.000). Linear mixed models identified particle size of DBBM as a critical factor associated with vertical bone resorption (p=.000). The GV gradually increased during the follow-up period. Rapid and unavoidable peri-implant bone resorption usually happened during the first 6months after implant placement. GBR is a predictable treatment for maxillary anterior implants, since GV has an increasing trend. Large bone particles of DBBM help maintain vertical alveolar bone stability.

Radiomorphometric analysis of edentulous posterior mandibular ridges in the first molar region: a cone-beam computed tomography study.

PurposeThe aim of our study was to determine the prevalence and degree of lingual concavities in the first molar region of the mandible to reduce the risk of perforating the lingual cortical bone during dental implant insertion.MethodsA total of 163 suitable cross-sectional cone-beam computed tomography images of edentulous mandibular first molar regions were evaluated. The mandibular morphology was classified as a U-configuration (undercut), a P-configuration (parallel), or a C-configuration (convex), depending on the shape of the alveolar ridge. The characteristics of lingual concavities, including their depth, angle, vertical location, and additional parameters, were measured.ResultsLingual undercuts had a prevalence of 32.5% in the first molar region. The mean concavity angle was 63.34°±8.26°, and the mean linear concavity depth (LCD) was 3.03±0.99 mm. The mean vertical distances of point P from the alveolar crest (Vc) and from the inferior mandibular border were 9.39±3.39 and 16.25±2.44, respectively. Men displayed a larger vertical height from the alveolar crest to 2 mm coronal to the inferior alveolar nerve (Vcb) and a wider LCD than women (P<0.05). Negative correlations were found between age and buccolingual width at 2 mm apical to the alveolar crest, between age and Vcb, between age and Vc, and between age and LCD (P<0.05).ConclusionsThe prevalence of lingual concavities was 32.5% in this study. Age and gender had statistically significant effects on the lingual morphology. The risk of lingual perforation was higher in young men than in the other groups analyzed.

Assessment of the effect of different imaging techniques on planning implant therapy by different clinicians

Aim: To compare the implant size which was determined by different observers using panoramic radiography (PAN) and cone beam computed tomography (CBCT) with inserted implant size.Material and Methods: 194 PAN and CBCT images which belong to 194 patients who were planned to undergone single-tooth implant therapy were evaluated. 50 anterior regions, 42 premolar regions and 92 molar regions were assessed. These sites were used for planning of dental implant insertion. Images were analyzed by observers with different education and clinic experience backgrounds: one periodontist (observer 1), one oral and maxillofacial radiologist (observer 2), and one general practitioner (observer 3). Panoramic images and cross-sectional CBCT images of each patient were examined; differences in length and width of the implant-to-be from the two imaging systems were analyzed and compared to inserted implant size.Results: Observer 2 recorded the largest implant width whereas observer 3 recorded narrower implants in PAN. Observer 3 recorded shortest implants than did the other two observers in CBCT and observer 2 recorded narrower implants in CBCT. The CBCT measurements allowed a wider implant in the premolar and molar regions. No significant difference was observed between CBCT and PAN in planning the implant length. The inserted implant size was smaller than the measurements made in CBCT.Conclusion: The results show that; different observers present different values in determining implant length and width. The inserted implant size and the dimensions measured on CBCT and PAN images were different.

Evaluation of the relationship between appearances of the lingual foramen on panoramic radiography and cone-beam computed tomography

The aim of this retrospective study is to determine the level of visibility of the lingual foramen in panoramic radiography using cone-beam computed tomography (CBCT) as a reference tool. A total of 200 patients (111 females and 89 males) were included in the study. Cross-sectional CBCT images of the mandible in the midline were used to locate and define the orifice and diameter of each lingual canal that was detected. The appearance of the lingual foramen in the anterior mandible in panoramic radiography was assessed using a five-point ordinal scale. Descriptive statistics including tables and graphs were used. The correlation between CBCT and panoramic radiography findings were analyzed using Chi-square tests. The lingual foramen was found to be located most frequently in the mandibular midline, above the genial tubercle (78.5%). A narrow-diameter type was found to occur most frequently (56.5%). A prominent genial tubercle was the most commonly found type (57.5%). The lingual foramen could be definitively identified in panoramic radiographs in only 8 cases (4%), while a high degree of probability was found in 25 cases (12.5%). The lingual foramen appears wider and therefore more distinctive in panoramic radiographs when the angulation of the lingual canal is less than 20° to the ground plane. Radiological evaluation with panoramic radiographs alone may lead to inadequate assessments prior to surgical procedures involving the anterior mandible. Clinicians may consider using three-dimensional imaging for procedures with a risk of hemorrhagic and neurosensory complications such as dental implant placement in the anterior mandible.

Evaluation of trabecular pattern of mandible using fractal dimension, bone area fraction, and gray scale value: comparison of cone-beam computed tomography and panoramic radiography.

This study was performed to compare the fractal dimension (FD), bone area fraction (BAF), and gray scale value (GSV) on digital panoramic radiography (DPR) and cross-sectional cone-beam computed tomography (CBCT) using image analysis and to determine whether a relationship exists among parameters associated with bone quality. Thirty edentulous human hemimandibles were scanned by DPR and CBCT. Ninety regions of interest (ROIs) were evaluated on DPR and CBCT images to calculate the FD and BAF. The GSV of the ROI on CBCT was also calculated. Statistically significant differences were observed in the FD values of the ROIs between DPR and CBCT (p = 0.002) and in the BAF values of ROIs between DPR and CBCT (p = 0.017). The Spearman's correlation test revealed a statistically significant high correlation between the FD and BAF values of the ROIs on DPR and between the FD and BAF values of the ROIs on CBCT (p < 0.01). No significant correlations were observed between the GSVs of ROIs on CBCT and the FD values of ROIs on DPR, the BAF values of ROIs on DPR, the FD values of ROIs on CBCT, and the BAF values of ROIs on CBCT (p > 0.05). The GSV did not support the FD and BAF. Additionally, DPR and CBCT did not have similar image quality for assessing the FD, BAF, and GSV. In evaluating the trabecular structure, the use of panoramic radiographs should be continued because the image resolution of CBCT is lower and its generalized dose is higher than that of panoramic radiography. These results may serve as a reference for clinical practitioners using dental CBCT to analyze the trabecular structures of alveolar bones.

Evaluation of mental foramen location in the 10-70 years age range using cone-beam computed tomography.

Mental foramen (MF) locations were determined according to gender and age in terms of the vertical distance from the surrounding anatomical structures and the vertical and horizontal size of the MF. One hundred-seven male and 103 female patients in the age group between 10 and 70 years were included in our retrospective study and were examined using cone-beam computed tomography (CBCT). The right and the left MF locations were determined from panoramic and cross-sectional images. On the cross-sectional CBCT images, the distance of the MF upper limit from the alveolar crest edge, the distance of the MF lower limit from the lower edge of the mandible, and vertical size of the MF were measured. MF location differed in males and females (P < 0.001); it was generally located at the first and second premolar in females, and at the level of the second premolar in males. However, the MF location was not different on the right and left sides (P = 0.436). The distance of the MF from the surrounding anatomic structures were found to be lower in females than in males in all measurements (P < 0.001). The horizontal size of the MF was found to be less on the left side (P < 0.001). Knowing both the position and the distance of the MF from the surrounding anatomical structures is not only useful information for surgery, but will also help avoid complications such as paresthesia.

Topographic relationship between root apex of mesially and horizontally impacted mandibular third molar and lingual plate: cross-sectional analysis using CBCT.

The present study was aimed to determine the topographic relationship between root apex of the mesially and horizontally impacted mandibular third molar and lingual plate of mandible. The original cone beam computed tomography (CBCT) data of 364 teeth from 223 patients were retrospectively collected and analyzed. The topographic relationship between root apex and lingual plate on cross-sectional CBCT images was classified as non-contact (99), contact (145) and perforation (120). The cross-sectional morphology of lingual plate at the level of root apex was defined as parallel (28), undercut (38), slanted (29) and round (4). The distribution of topographic relationship between root apex and lingual plate significantly associated with gender, impaction depth, root number and lingual plate morphology. Moreover, the average bone thickness of lingual cortex and distance between root apex and the outer surface of lingual plate were 1.02 and 1.39 mm, respectively. Furthermore, multivariate regression analyses identified impaction depth and lingual plate morphology as the risk factors for the contact and perforation subtypes between root apex and lingual plate. Collectively, our findings reveal the topographic proximity of root apex of impacted mandibular third molar to the lingual plate, which might be associated with intraoperative and postoperative complications during tooth extraction.

Comparison of cone-beam computed tomography and osteometric examination in preoperative assessment of the proximity of the mandibular canal to the apices of the teeth

The risk of postoperative neurosensory impairment after extraction of a third molar will be greater if the inferior alveolar nerve is in close proximity to the apices of the root. Precise preoperative evaluation of the relative positions of the nerve and the mandibular apices is important to protect the nerve from mechanical irritation. The aim of this study was to assess the accuracy of cone-beam computed tomography (CT) in the identification of the positional relations of the mandibular third molar and the inferior alveolar canal using Rood’s criteria.Panoramic images of 10 dry hemimandibles were obtained, and 20 teeth each with one of Rood’s criteria indicating close relations to the mandibular canal were selected. Cone-beam CT images of the selected points were obtained. The closest distance between the apex of the root and the inferior alveolar canal was measured on cross-sectional cone-beam CT images. The same measurements were made on the corresponding osteometric sections with digital callipers. The intra-class correlation coefficient (ICC) was used to measure the consistency between the two measurements as the reference method, and showed that there was a high level of inter-rater agreement (r>0.90). The mean (SD) deviation of cone-beam CT measurements from the gold standard osteometric measurements was small at 0.30 (0.24). There were almost perfect matches between cone-beam CT and gold standard measurements. Cone-beam CT is an accurate technique to measure the proximity of the mandibular apices to the alveolar nerve.

Diagnostic Value of Panoramic Radiography, Cone Beam Computed Tomography (CBCT) and Clinical Measurement in Determining Bone Dimensions

Introduction: Calculation of the bone dimensions is of great importance for implant treatment. Several radiographic modalities have been used for this purpose. This study compared the accuracy of mesiodistal measurements of bone using panoramic radiography, cone beam computed tomography (CBCT), and the clinical methods. Methods: In this descriptive cross-sectional study, panoramic and CBCT images were obtained from 100 implant patients. Mesiodistal bone dimensions (distance between tooth CEJ in the mesial of edentulous region and CEJ of the tooth in distal of edentulous region) were calculated using a scaled ruler on the orthopantomograms and the system software in the CBCT images. During the implant insertions, a mucoperiosteal flap was raised and clinical dimensions of the bone were measured by a periodontal probe and bone gauge. The differences of bone height and thickness measurements between gold standard and CBCT or panoramic modalities were analyzed using Student’s t- test. Results: The mean bone height was 10.64±1.55, 11.44±1.51, and 10.68±1.6 mm in the clinical, panoramic and CBCT modalities, respectively. Statistically significant difference was noted between the clinical and panoramic techniques ( P 0.05). During the bone height calculations, 79%, 62% and 78% of the images were ranked in the normal range using CBCT, panoramic and gold standard measurements, respectively. The mean areas under the ROC curve were 0.92 and 0.83 in CBCT and panoramic techniques, respectively. Conclusion: Accuracy of the CBCT images was higher than panoramic technique in measuring the bone dimensions and this technique can be confidently used to calculate the bone dimensions for the implant surgeries. Keywords: Partially edentulous jaw; panoramic radiography; cone-beam computed tomography; bone dimensions

Evaluation of location and dimensions of mandibular lingual canals: a cone beam computed tomography study

This retrospective study evaluated the presence, location, and diameter of the mandibular lingual canals in a Taiwanese population using cone beam computed tomography (CBCT), to help improve the safety of mandibular surgical procedures. A total of 101 patients (46 men and 55 women), with a mean age of 55 years, were enrolled. Cross-sectional CBCT images of the mandible were used to define the orifice and diameter of each lingual canal detected. The relevance of all data for both sexes was assessed and analyzed statistically using non-paired t-tests. The canals were categorized as median (MLC) and lateral lingual canals (LLC) based on the position of the mandible. The midline of the symphysis showed the highest frequency of lingual canals (97.0%), and all patients exhibited at least one lingual perforating bone canal in the mandible. The lingual canal diameter ranged from 0.25 to 1.90mm (mean 0.61mm) in the midline region and from 0.25 to 1.60mm (mean 0.58mm) in the lateral region. Significant differences in diameter were observed between the sexes in the MLC and LLC groups (men>women). The results suggest that mandibular lingual vascular canals are common and detected regularly using CBCT.

Cone-Beam Computed Tomography Evaluation of Horizontal and Vertical Dimensional Changes in Buccal Peri-Implant Alveolar Bone and Soft Tissue: A 1-Year Prospective Clinical Study.

This study evaluated changes in the horizontal and vertical dimensions of the buccal alveolar bone and soft tissue over a 1-year period following implant prosthesis. Thirty-three participants with no history of guided bone regeneration or soft tissue augmentation underwent dental implant placement with different types of connections. The dimensions of the buccal alveolar bone and soft tissue were evaluated immediately and at 1 year after prosthesis from reconstructions of cross-sectional cone-beam computed tomography images. The vertical and horizontal loss of buccal bone and soft tissue around implants with conical connections were lower than around those with external or internal connections. Statistically significant negative correlations were observed between initial horizontal bone thickness and changes in vertical bone and soft tissue height (p < .05), and between initial horizontal soft tissue thickness and the change in vertical soft tissue height (p < .05). Implants with a conical connection preserve peri-implant alveolar bone and soft tissue more effectively than other connection types. Furthermore, the initial buccal alveolar bone and soft tissue thickness around the implant platform may influence their vertical dimensional changes at 1 year after implant prosthesis.

Facial bone alterations on maxillary anterior single implants for immediate placement and provisionalization following tooth extraction: a superimposed cone beam computed tomography study.

The purpose of this cone beam computed tomography (CBCT) study was to describe the facial bone changes around single implants for immediate placement and provisionalization following tooth extraction in the maxillary anterior. The data between 2008 and 2013 were collected retrospectively. Superimposed facio-palatal cross-sectional CBCT images for the implants were derived from preoperative and postoperative radiographs via standardized CBCT processes. Horizontal and vertical facial measurements on the implants were identified at preoperative and approximately 1-year postoperative follow-ups. Correlation coefficient for those parameters was evaluated. A total of 12 single implants in 12 patients were included in this study. The mean loading period was 13.3months (range 12-15months). The median data of preoperative bone thickness 0.54mm (A), preoperative vertical bone level 1.46mm (B), postoperative bone thickness 1.77mm (C), postoperative vertical bone level 1.08mm (D), horizontal distance from outer surface of preoperative facial bone to implant surface 2.08mm (E), horizontal gap distance 1.41mm (E-A), horizontal bone resorption -0.26mm (E-C), and vertical bone resorption -0.25mm (B-D) were obtained. The data at the implant platform level (IPL) were selected for the horizontal measurements. Spearman's analysis demonstrated statistically significant correlations between B and D, C and E, E and E-A, and B and E-C (P<0.01). Significant correlations between C and B, D, and E-A were also found, respectively (P<0.05). Immediate placement and provisionalization of single implants procedure in the maxillary anterior showed excellent outcomes with the small facial bone alterations around the implants. Neither preoperative facial bone thickness nor horizontal gap distance influenced the amount of facial bone resorptions.

The evaluation of idiopathic osteosclerosis on panoramic radiographs with an investigation of lesion′s relationship with mandibular canal by using cross-sectional cone-beam computed tomography images

Objective: The aim of this study was to determine the prevalence of idiopathic osteosclerosis (IO) in a Turkish population on orthopantomographs with respect to age, sex, and lesion characteristics and investigate the lesion's relationship with mandibular canal with the aid of cross-sectional cone-beam computed tomography (CBCT) images. Materials and Methods: 8000 panoramic radiographs taken with two digital orthopantomograph devices over a 10-month period were evaluated. Each patient was assigned an identification number, and demographic information (age, sex), absence/presence of a lesion, and if present, lesion characteristics (localization, dental relationship, size, and shape) were recorded. Additionally, cross-sectional CBCT images of 30 patients with IO were examined in terms of relationship with mandibular canal. Results: 273 IO lesions were detected in 225 patients (130 females, 95 males; mean age: 33.1 years). The majority of lesions were observed in the mandibular premolar and molar areas. IO lesions occurred more frequently among middle-aged individuals and at higher rates among females (3.1%, n = 130) than males (2.8%, n = 95); however, differences by age and sex were not statistically significant (P > 0.05). Cross-sectional images revealed that 80% of the lesions were in contact with mandibular canal. None of the lesions showed any cortical expansion. Conclusions: This large-scale study found IO to have a low prevalence rate among a Turkish population. IO was observed to occur more frequently in females than in males and to be most common among individuals aged 20-29. CBCT results suggested a possible association between IO lesions and mandibular canal.

Correlation of mandibular impacted tooth and bone morphology determined by cone beam computed topography on a premise of third molar operation

To determine the width and morphology of the mandible in the impacted third molar region, and to identify the location of the mandibular canal prior to planning impacted third molar operations. Cone beam computed tomography (CBCT) data of 87 mandibular third molars from 62 Japanese patients were analyzed in this study. The width of the lingual cortical bone and apex-canal distance were measured from cross-sectional images in which the cortical bone was thinnest at the lingual side in the third molar region. Images were used for measuring the space (distance between the inner border of the lingual cortical bone and outer surface of the third molar root), apex-canal distance (distance from the root of the third molar tooth to the superior border of the inferior alveolar canal) and the cortical bone (width between the inner and outer borders of the lingual cortical bone). The means of the space, apex-canal distance and lingual cortical width were 0.31, 1.99, and 0.68mm, respectively. Impacted third molar teeth (types A-C) were observed at the following frequencies: type A (angular) 37%; type B (horizontal), 42%; type C (vertical), 21%. The morphology of the mandible at the third molar region (types D-F) was observed as: type D (round), 49%; type E (lingual extended), 18%; and type F (lingual concave), 32%. The width and morphology of the mandible with impacted teeth and the location of the mandibular canal at the third molar region could be clearly determined using cross-sectional CBCT images.