Repetition Rate of Scanning Due to Motion Artefacts in Cone-Beam Computed Tomography: a Retrospective Study.

Objectives: The objective of this retrospective study was to investigate the incidence of repeated cone-beam computed tomography scans due to motion artefacts in a Turkish subpopulation. Material and Methods: A total of 6364 patients' cone-beam computed tomography data were analysed retrospectively to identify repeated scans due to motion artefacts. Patients were divided into eight age groups: 1) < 10-year-olds, 2) 10 to 19-year-olds, 3) 20 to 29-year-olds, 4) 30 to 39-year-olds, 5) 40 to 49-year-olds, 6) 50 to 59-year-olds, 7) 60 to 69-year-olds, and 8) > 70 year-olds. Chi-square test was applied to evaluate the repetition rate of scans by age and gender groups. Statistical significance was set at P < 0.05. Results: Repeated scans due to motion artefacts were observed in 1.96% of the patients. The repetition rate of scans was significantly higher in males than in females (P = 0.006). Furthermore, the repetition rate of scans was significantly higher in patients < 10 years old compared to the other age groups. However, there was no significant difference in the repetition rate of scans due to motion artefacts among the other age groups (P > 0.05). Conclusions: The present findings suggest that patient age and gender are associated with repeated cone-beam computed tomography scans due to motion artefacts. Males and children under the age of 10 had more common repeated scans due to motion artefacts.

Risk assessment of mandibular incisive canal perforation during dental implant surgery in the anterior edentulous mandible: a virtual implant placement study using cone beam computed tomography.

OBJECTIVE: The aim of this study was to evaluate the risk of mandibular incisive canal (MIC) perforation caused by implants placed on cone beam computed tomography (CBCT) images in the edentulous mandibular anterior region. STUDY DESIGN: A total of 1200 dental implants were virtually inserted on 150 eligible CBCT scans. The relationship of different implant sizes with the incidence of MIC perforation and the relationship between crest height and perforation were evaluated. RESULTS: A total of 1200 virtual implant applications were performed on 150 patients. In 87% of cases, MIC was identified. Perforation in 12 and 14 mm implants was significantly higher than in 8- and 10-mm implants (P < .05). Perforation was found to be statistically significantly higher in crest heights that were ≤20 mm than in crest heights >20 mm (P < .05). CONCLUSIONS: Our results showed high perforation rates in the 12- and 14-mm implants and crests heights that were ≤20 mm during implant surgery in the mandibular anterior edentulous region. Perforation of the MIC should be considered a complication of implant surgery in the mandibular anterior region; therefore, CBCT images should be evaluated before implant placement.

Risk Assessment of Lingual Plate Perforation in Anterior Edentulous Mandibular Region: A Virtual Implant Placement Study Using Cone-Beam Computed Tomography.

BACKGROUND: The aim of this study was to evaluate the prevalence of lingual cortical bone perforation caused by virtually placed implants on cone-beam computed tomography images in the edentulous mandibular canine region and determine the relationship between the morphological structure of the crest and the risk of perforation. METHODS: Eight hundred dental implants were virtually inserted on 100 qualified cone-beam computed tomography scans. Crests were divided into 4 groups according to the crest morphology as Type U, Type L, Type P, and Type C. The distance between the implant tip and lingual plate was measured using a digital caliper. Incidence of lingual plate perforation and proximity of the implant tip to the lingual plate were measured for 4 types of the alveolar crest. RESULTS: A total of 800 virtual implant applications were performed in 100 patients who met the inclusion criteria. The incidence of lingual plate perforation was found to be significantly higher in Type U crests than in the other types. It was also found to be statistically significantly higher in Type L crests than in Type P and Type C crests. When the relationship between implant length and perforation was evaluated, perforation in 14 mm implants was significantly higher than 8, 10, and 12 mm implants. CONCLUSIONS: According to the results of this study, it was determined that high rates of perforation occurred in the U and L type crests and 14 mm implants during implant surgery in the mandibular anterior edentulous region.

Evaluation of stylohyoid complex in subjects with different types of malocclusions using cone-beam computed tomography: a retrospective study in a Turkish subpopulation.

PURPOSE: According to the functional matrix theory, the development of maxillomandibular complex may be affected by the surrounding tissues. The aim of this study was to evaluate the length and angulation of the styloid process in different types of malocclusions using cone-beam computed tomography (CBCT). METHODS: Angulations and length of the styloid process were evaluated in CBCT images of 97 individuals retrospectively. The patients were classified as class I, II, and III groups according to sagittal skeletal classes. The mean length, anterior angulation, and medial angulation of the styloid process were analyzed. Statistical significance was evaluated at p < 0.05. RESULTS: The mean styloid process length in group class III was found to be significantly longer than class I (p: 0.035). Anterior angle was significantly higher in class III group than in other groups (p < 0.05). No statistically significant difference was found in medial angle between the groups (p: 0.506). CONCLUSION: According to present findings, class III malocclusion is associated with the stylohyoid complex morphology due to longer styloid process lengths and higher anterior angle values.

Radiographic Evaluation of Infraorbital Canal Protrusion into Maxillary Sinus Using Cone-Beam Computed Tomography.

OBJECTIVES: The aim of this retrospective study was to evaluate the relation of the infraorbital canal course with the maxillary sinus using cone-beam computed tomography. MATERIAL AND METHODS: A total of 1000 infraorbital canals (IOC) were examined from 500 cone-beam computed tomography scans. IOCs were classified into three types based on the degree of protrusion into the sinus. The presence of Haller cells and mucosal thickening in the sinus were evaluated. The length of bony septum from the canal to the sinus wall (D1), the distance at which protrusion begins posterior to the inferior orbital rim (D2), the vertical distance from the canal to the sinus roof (D3), and the vertical distance from the canal to the sinus floor (D4) were measured. RESULTS: The prevalence of IOC protrusion into the sinus was 8.8%. There was a significant difference in the prevalence of Haller cells between IOC types (P < 0.01). However, no significant correlation was found between IOC types and the presence of mucosal thickening (P > 0.05). There was no significant difference in the mean D1, D2, and D3 between the genders (P > 0.05). The mean D4 was significantly higher in males than in females (P < 0.05). CONCLUSIONS: The protrusion of infraorbital canals into the sinus is a common variation that must be considered to prevent accidental injury. Our findings suggest that the risk of injury to the descending canals is very low during routine dentoalveolar procedures because the protruded canal is not close to the sinus floor.

Cone-Beam Computed Tomographic Evaluation of Styloid Process in Patients With Temporomandibular Disorders and Asymptomatic Individuals.

OBJECTIVES: Elongated styloid processes (ESP) may show clinical symptoms that are readily confused with symptoms associated with temporomandibular disorders (TMDs). The purpose of study was to compare the prevalance and characteristics of ESP in patients with TMD and asymptomatic individuals are examined by cone beam computed tomography. METHODS: Angulations and length of the styloid process (SP) were evaluated in CBCT images of 100 patients with TMD symptoms and 100 control patients, retrospectively. Differences between the patient and control groups were assessed by analysis independent sample t test. Pearson correlation test was used to evaluate between length and angulation of SP relationship. RESULTS: The mean length of SP in the TMD group was 38.19 ±â€Š8.6 mm for the right and 38.99 ±â€Š8.1 mm for the right side. The mean length of SP in the control group was 36.80 ±â€Š6.3 for the right side and 36.18 ±â€Š6.5 mm for the left side. The mean anterior angulation of the SP in the TMD group was 22.08 ±â€Š5.5 degree in the TMD group and 23.97 ±â€Š4.1 degree in the control group. The mean medial angulation of the SP in the TMD group was 30.57 ±â€Š4.9 degree and 29.89 ±â€Š4.4 degree in the control group. There was no significant difference in length and angle between the groups (P > 0.05). CONCLUSION: No correlation was found in terms of length and angulations of SP between TMD and control groups.

Localization of the Mandibular Canal in a Turkish Population: a Retrospective Cone-Beam Computed Tomography Study.

OBJECTIVES: The aim of this study was to determine the location of the mandibular canal at the mental foramen region that is essential in order to prevent injuries to the inferior alveolar neurovascular bundle during mandibular surgical procedures. MATERIAL AND METHODS: The position of the mandibular canal was analysed using cone-beam computed tomography images from 300 Turkish patients, who were referred to Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Izmir Katip Celebi University for various complaints. The distances of the mandibular canal to the outer superior (D1), inferior (D2), buccal (D3), and lingual (D4) cortical margins were measured at 2 mm distal to the mental foramen. RESULTS: There were 148 (49.3%) males and 152 (50.7%) females with ages ranging from 15 to 74 years (39.15 [SD 17.8]). D1 was significantly greater than D2 and D3 was significantly greater than D4 on both left and right sides. While the mean D1, D2, and D4 in males were significantly greater than in females on both left and right sides. There was no significant difference between D3 in males and females on both left and right sides. CONCLUSIONS: The results showed that the mandibular canal was vertically located nearer to the inferior cortical border and horizontally nearer to the lingual cortical border of the mandible at the mental foramen region. Knowledge of the distances of mandibular canal to the outer cortical margins at this region of the mandible will be helpful for surgical procedures.

Investigation of maxillary sinus volume relationships with nasal septal deviation, concha bullosa, and impacted or missing teeth using cone-beam computed tomography.

OBJECTIVES: The aim of this retrospective study was to investigate the correlations of maxillary sinus volume with nasal septal deviation, concha bullosa, impacted teeth, and missing teeth in the maxillary posterior region on maxillary sinus volume using cone-beam computed tomography (CBCT) images. METHODS: The study cohort comprised 252 CBCT images of 252 patients retrospectively selected from the records in our CBCT archive. All CBCT images were exported to 3D modeling software for calculation of maxillary sinus volumes. Nasal septal deviation cases were grouped as mild, moderate, and severe. Concha bullosa was classified as lamellar, bulbous, and extensive. Maxillary sinus volume differences were evaluated by comparing the bilateral sinus volumes in patients with nasal septal deviation, unilateral concha bullosa, and unilateral impacted or missing maxillary posterior teeth. RESULTS: The findings revealed that males had a significantly higher mean sinus volume than females (p < 0.01) and that sinus volume tended to decrease with age (p < 0.05). In moderate and severe nasal septal deviation cases, the maxillary sinus volume was significantly smaller on the same side as the deviation than on the contralateral side (p < 0.05). There were no significant correlations between maxillary sinus volume and concha bullosa, unilateral impacted teeth, or unilateral missing teeth (p > 0.05). CONCLUSIONS: The present findings suggest that maxillary sinus volume is smaller on the same side as the deviation in moderate and severe septal deviation cases and that the maxillary sinus volume tends to decrease with increasing age.

Does Unilateral Cleft Lip and Palate Affect the Maxillary Sinus Volume?

OBJECTIVE: The purposes of this study were to evaluate and compare the maxillary sinus volume (MSV) of patients with a unilateral cleft lip and palate (UCLP) between the cleft side and noncleft side and between adolescent patients with UCLP and a control (noncleft) group using cone beam computed tomography (CBCT). METHODS: CBCT images of 44 UCLP patients (29 males and 15 females, with a mean [SD] age of 13.5 [5.0] years) and 44 (22 males and 22 females, with a mean [SD] age 14.9 [4.2] years) age- and sex-matched controls were evaluated in this study. Each maxillary sinus was assessed 3-dimensionally, segmented, and its volume was calculated. RESULTS: There were no statistically significant differences between the age and gender distributions of the groups. There was a statistically significant difference in the MSVs of the cleft (10996.78±3522.89 mm3) versus the noncleft side (10382.3±3416.2 mm3; P < .05)] but no significant difference between the MSVs of the right and left sides ( P > .05). In the intergroup comparison, the mean MSVs of the UCLP patients (10701.52±3369.33 mm3) were significantly smaller than those of the control group (16054.08 ± 5293.96 mm3; P < .001). CONCLUSIONS: The MSVs of the UCLP patients showed a statistically significant decrease compared to those of the controls ( P < .001). There was also a significant difference in the MSVs of the cleft and noncleft sides of the UCLP patients ( P < .05).

Evaluation of pre-eruptive intracoronal resorption on cone-beam computed tomography: A retrospective study.

OBJECTIVES: This retrospective study aimed to investigate the prevalence of pre-eruptive intracoronal resorption (PIR) in unerupted permanent teeth in a Turkish population using cone beam computed tomography (CBCT). METHOD: A total of 1,317 CBCT images were screened. In all the images, the following were recorded: the number of unerupted teeth, number of teeth with intracoronal resorption, affected tooth type and number, and location of radiolucent defects. Demographic data were also obtained. RESULTS: The prevalence of intracoronal resorption in the study group was 15.1%, with a prevalence in teeth of 3.5%. The prevalence of intracoronal resorption using CBCT was much higher than that recorded previously using panoramic or bitewing radiographs intracoronal resorption was more common in males (57%) than females (43%). Twenty-three cases were located in the maxilla (48%), and 25 were located in the mandible (52%). The mandibular third molar was the most affected tooth type, followed by maxillary third molars and supernumerary teeth. CONCLUSION: CBCT can be useful for diagnosing PIR defects because it provides an accurate representation of internal dental anatomy. SCANNING 38:442-447, 2016. © 2016 Wiley Periodicals, Inc.