Evaluation of the oropharynx in class I and II skeletal patterns by CBCT

Purpose

This study aimed to evaluate the dimensions of the oropharynx and its shape in the minimum cross-sectional area, in individuals with Class I and Class II skeletal patterns, using three-dimensional CBCT images.

Methods

Forty-two cone-beam computed tomography images of grown individuals were evaluated. The images were divided according to the patient’s skeletal patterns. The dimensions of the oropharyngeal airway space were determined using the Dolphin Imaging software.

Results

The volume and the minimum cross-sectional area were greater in patients with a Class I skeletal pattern, with a median difference of 5379 mm³ and 86.8 mm², respectively. The anteroposterior and lateral diameters in the minimum cross-sectional area were also higher in Class I individuals (2.3 and 6.0 mm, respectively), but the ratio between them was not different.

Conclusions

The volume and the minimum cross-sectional area of the oropharynx, as well as the anteroposterior and lateral diameters, are lower in individuals with a class II skeletal pattern than in individuals with a class I skeletal pattern. There was no difference in the shape of the oropharynx in healthy individuals with different skeletal patterns.

     

Three-dimensional evaluation of the pharyngeal airway using cone-beam computed tomography following bimaxillary orthognathic surgery in skeletal class III patients

Objective

The study aims to evaluate the pharyngeal airway space (PAS) following bimaxillary surgery in skeletal class III patients and to compare the changes in PAS between genders using cone-beam computed tomography (CBCT).

Materials and methods

In all, 38 patients (16 male and 22 female) with skeletal class III malocclusion underwent bimaxillary surgery. CBCT scans were acquired approximately 1 month before surgery, 3 months after surgery, and 6 months after surgery. The oropharyngeal volume and the minimum cross-sectional area (CSA) were characterized using the InVivoDental imaging software package at each time point.

Results

The volume and minimum CSA decreased significantly postoperatively, which was maintained until 6 months postoperatively (p < 0.01). The location of the minimum CSA tended to move into the retropalatal and retroglossal areas postoperatively. A strong correlation between volume and minimum CSA was found. The amount of mandibular setback was not correlated with the change in the airway. By gender, significant decreases in both the volume and minimum CSA were found in females (p < 0.05) but not in males.

Conclusion

Bimaxillary surgery significantly affects PAS. Gender differences should also be considered when considering changes in PAS.

Clinical relevance

An awareness of the effects of bimaxillary setback surgery on the airway should be considered when implementing an orthognathic treatment plan.

     

Evaluation of anatomical variations of the nasal cavity and ethmoidal complex on cone-beam computed tomography

Objectives

The purpose of this study was to evaluate the prevalence of anatomical variations of the nasal cavity and ethmoid complex on cone-beam computed tomography (CBCT) images.

Methods

The CBCT images of 322 patients were evaluated retrospectively. The anatomical variations of the bilateral nasal cavity and ethmoidal complex were evaluated in four categories, namely nasal septum, turbinates, ethmoid air cells, and crista galli.

Results

The patients comprised 134 males (41.6 %) and 188 females (58.4 %), with an age range of 18–83 years. One or more nasal septum variations were observed in 76.7 % of patients, while variations in the turbinate and ethmoid cell categories were present in 89.4 and 62.1 % of patients, respectively. Overall, 5 % of patients showed pneumatized crista galli.

Conclusions

The detailed radiographic examination of the nasal cavity and ethmoid complex is possible and successful on the CBCT images.

     

Upper airway imaging in sleep-disordered breathing: role of cone-beam computed tomography

Objective

To review recent use of three-dimensional (3D) imaging, specifically cone-beam computed tomography (CBCT), in the analysis of the upper airway for diagnosis or treatment outcomes in patients with sleep-disordered breathing (SDB).

Types of studies reviewed

Literature review of relevant medical and dental studies utilizing 3D imaging to assess the upper airway.

Results

Imaging of the upper airway provided insight into potential areas of obstruction. Accessibility of CBCT to dentists is reflected in several applications of upper airway diagnosis, treatment planning, and different treatment outcomes, as well as association with craniofacial development. However, multiple deficiencies in image acquisition, 3D reconstruction, and analysis are evident.

Practical implications

The role of CBCT in the analysis of the upper airway is growing; however, critical limitations remain. An understanding of these limitations, clarification of misconceptions, and improvements in analysis methods are required to ensure proper use and development of CBCT.

     

Evaluation of retromolar canals on cone beam computerized tomography scans and digital panoramic radiographs

Purpose

The purpose of this study was to carry out morphologic and topographic analyses of retromolar canals on cone beam computerized tomography (CBCT) scans, comparing findings to others obtained from the corresponding digital panoramic radiographs.

Methods

Sixty-one CBCT scans were analysed digitally, as well as their corresponding digital panoramic radiographs. The prevalence and distribution of these canals, foramen diameters, and intraosseous communications were also evaluated.

Results

On CBCT scans, we found that 24.6% of individuals had at least one retromolar canal. The mean foramen diameter was slightly higher than 1 mm and we could not determine the intraosseous anatomical connections in most cases. The morphology and topography of the retromolar canals were not affected by gender and antimere. In addition, only 22.2% of all tomographically identified canals could be confirmed on digital panoramic radiographs (26.7% of such patients). Regarding all sample, 6.6% of individuals showed retromolar canals on digital panoramic radiographs.

Conclusion

We may consider that these structures are clinically relevant findings and, due to the low accuracy of the panoramic radiographs, high-quality tomographic exams should always be asked for presurgical treatment planning.

     

Construction of a low-cost surface scanner for medical studies: a feasibility study

Purpose

This article describes the assembly of a cost-efficient system to enable contact-free volumetric measurement of facial volumes.

Methods

The system was built from low-cost standard equipment, including Lego bricks, standard CCD camera, laser module, USB board, and stepper motor. The total cost was less than 200 €. At different time intervals, depth data were captured with a sweeping laser line to subsequently determine volumetric models of the object under investigation.

Results

The obtained volumetric data were imported in the open-source software ParaView (Kitware Inc., New York, NY, USA) as standard comma-separated files. The absolute errors of the obtained depth values increased from 0.5 to 3.52 mm between 30 and 90 cm of defined object distance, respectively. The relative errors increased from 0.3 to 0.76 %, respectively.

Conclusions

This study proves that applicable volume scanners can be built using low-cost components.

     

Increased local recurrence in advanced parotid malignancy treated with mastoidectomy without lateral temporal bone resection

Objective

We analyzed patients with advanced parotid malignancy requiring proximal facial nerve exposure undergoing mastoidectomy versus lateral temporal bone resection to determine differences in local and distant recurrence.

Study design

The study design is a case series with chart review.

Setting

The setting is in Tertiary care practice in Fort Worth, Texas from January1998 to January 2014.

Subjects and methods

The study included 120 patients with advanced parotid malignancy, 82 males between 19 and 87 years, and 38 females between 26 and 83 years. Patients with no overt bone involvement were treated with parotidectomy and mastoidectomy for exposure of the proximal facial nerve, and patients with clinically suspected (radiographic imaging or clinical fixation) bone involvement were treated with parotidectomy and lateral temporal bone resection. Follow up ranged from a minimum of 18 months to 11 years following surgery.

Results

Sixty patients were treated with mastoidectomy and 60 were treated with lateral temporal bone resection. In patients treated with mastoidectomy, 13 had local recurrence and 7 had distal recurrence. In patients treated with lateral temporal bone resection, 2 had local recurrence while 9 had distant recurrence. Statistical analysis revealed that patients treated with mastoidectomy developed local recurrence (p = 0.0022) more commonly than those treated with lateral temporal bone resection. There was no significant difference in distant recurrence between both groups (p = 0.5949).

Conclusions

Patients with advanced parotid malignancy should be treated aggressively with parotidectomy and lateral temporal bone resection regardless of bone involvement due to increased risk of local recurrence in those treated with mastoidectomy alone.

Level of evidence

Level of evidence is a 4 case series.

     

Can gray values derived from CT and cone beam CT estimate new bone formation? An in vivo study

Objectives

The main aim of this study was to investigate whether Hounsfield unit derived from computed tomography (HU/CT) and gray value derived from cone beam computed tomography (GV/CBCT) can predict the amount of new bone formation (NBF) in the defects after bone reconstruction surgeries.

Materials and methods

Thirty calvaria defects created in 5 rabbits and grafted with both radiolucent (RL, n = 15) and radiopaque (RO, n = 15) bone substitute materials were evaluated, 8 weeks postoperatively. The defects were scanned by multislice computed tomography (Somatom®, Siemens Healthineers, Erlangen, Germany) and CBCT (NewTom VG®, Qualitative Radiology, Verona, Italy). MSCT and CBCT scans were matched to select the exact region of interest (ROI, diameter = 5 mm and height = 1 mm). HU/CT and GV/CBCT of each ROI were obtained. Mean amount of NBF in whole of the defects was measured using serial histomorphometric assessment. We investigated the correlation between HU/CT and GV/CBCT, HU/CT and NBF, and GV/CBCT and NBF generally, and separately among the RL or RO grafted defects, by linear generalized estimating equation modeling. Receiver operation characteristic analysis was performed to check the accuracy of HU/CT and GV/CBCT in diagnosing more than 10% NBF in the samples.

Results

There were linear correlations between HU/CT and GV/CBCT, HU/CT and NBF, and GV/CBCT and NBF.

Conclusion

According to the results, both HU/CT and GV/CBCT can be considered as fairly good predictors for assessment of the amount of NBF following bone reconstruction surgeries.

     

Complicated Giant Pilomatrixoma of the Parotid Region

Objective

Pilomatrixoma (calcifying epithelioma of Malherbe) is a benign soft tissue tumour arising from dermis or subcutaneous tissue which should be considered in differential diagnosis of preauricular lesions especially when skin fixation is present.

Case Report

Twenty-three year old male referred to our clinic with complaint of left preauricular swelling over 18 months which enlarged and became painful in the last 2 months. Because the lesion showed signs of infection, surgery was planned after medical therapy was completed. FNAB suggest pleomorphic adenoma as preliminary diagnosis. US or MRI showed no specific feature.

Treatment and Prognosis

Total excision, superficial parotidectomy with facial nerve sparing was performed after regression of infectious signs. Postoperatively no recurrence was detected.

Conclusion

Pilomatrixomas are benign tumours but have diagnostic difficulties according to clinical and cytologic findings. This rare lesion should be kept in mind to avoid misdiagnosis as malign parotid tumours, particularly in the presence of skin change.

     

Evaluation of the maxillary third molar position and its relationship with the maxillary sinus: a CBCT study

Objectives

The present study investigated the position and relationship of the maxillary third molars to the maxillary sinus. These molars were detected to have a close relationship with the maxillary sinus based on panoramic images, using cone-beam computed tomography (CBCT).

Methods

This retrospective study evaluated 162 impacted third molars from 100 patients that showed a superimposed relationship between the maxillary sinus and third molars on panoramic images obtained from CBCT. CBCT images were used to assess the horizontal (buccopalatal) and vertical positions of the maxillary sinus relative to the maxillary third molars, proximity of the roots to the sinus, and angulation and depth of the third molars. The associations among the angulation, depth of third molars, and horizontal and vertical positions of the maxillary sinus relative to the third molar findings were examined using Chi square tests.

Results

Based on the winter classification, the most frequent tooth position was vertical (59.9 %), followed by mesioangular (14.2 %), distoangular (9.9 %), and others. Most impacted teeth were at the level between the occlusal and cervical levels of the adjacent second molar. Regarding the relationships of the maxillary third molars with the maxillary sinus examined on CBCT, vertical type III (buccal root related with maxillary sinus) (34 %) and horizontal type 2 (maxillary sinus located between roots) (64.8 %) were seen most frequently.

Conclusions

The relationship between the maxillary sinus and third molar roots should be considered during extraction. When a risk of sinus perforation is predicted in an extraction, a presurgical CBCT examination could be valuable.

     

Application of fractal analysis of the midpalatal suture for estimation of pubertal growth spurts

Objective

To evaluate the potential clinical application of fractal analysis of midpalatal suture fusion for prediction of pubertal growth spurts.

Methods

Cone-beam computed tomography (CBCT) scans and hand-wrist radiographs were obtained for 165 subjects (81 males, 84 females; mean age 15.5 ± 7.6 years). From the CBCT image of the midpalatal suture, the region of interest was obtained according to a previously described protocol. The fractal dimension (FD) of the midpalatal suture was calculated. Spearman’s correlation coefficients were estimated to investigate the associations among age, skeletal maturation index (SMI), and FD of the midpalatal suture. Receiver-operating characteristic curves were used to determine the cutoff values for identification of pubertal growth spurts.

Results

Significant correlations were observed among age, SMI, and FD of the midpalatal suture (P < 0.05). The optimal cutoff value of the FD for evaluation of a pubertal growth spurt was 0.9484 in males and 1.1205 in females. Fractal analysis of the midpalatal suture on CBCT images might be a clinically meaningful, objective, and quantitative method for evaluating pubertal growth spurts.

Conclusions

The present results suggest that fractal analysis of the midpalatal suture could be useful for decision-making on treatments involving growth modification in growing children with a skeletal discrepancy.

     

Recent Advances in Face Lift to Achieve Facial Balance

Introduction

Facial balance is achieved by correction of facial proportions and the facial contour. Ageing affects this balance in addition to other factors. We have strived to inform all the recent advances in providing this balance.

Method

The anatomy of ageing including various changed in clinical features are described. The procedures are explained on the basis of the upper, middle and lower face.

Results

Different face lift, neck lift procedures with innovative techniques are demonstrated.

Conclusion

The aim is to provide an unoperated balanced facial proportion with zero complication.

     

Relationship between maxillary sinus pathologies and maxillary posterior tooth periapical pathologies

Objectives

To determine the prevalence of odontogenic maxillary sinus pathologies and their relationship with periapical pathologies in the maxillary posterior teeth using cone-beam computed tomography (CBCT).

Method

Maxillary posterior CBCT scans of consecutive patients aged 20–77 years were evaluated retrospectively. Patients with at least one maxillary posterior tooth were included. Patients with edentulous maxillae or having one or more maxillary implants were excluded. Finally, 461 CBCT images were evaluated. Demographic data, such as age and sex, and pathologic findings of the right and left maxillary sinuses and adjacent teeth were recorded. Statistical analyses were performed using the Chi square test and binary logistic regression.

Results

The prevalence of right and left odontogenic maxillary sinusitis was 59.5 and 64 %, respectively. Maxillary sinus pathology was more common in males, and there was no relationship with age. Regarding the maxillary sinus pathology, 64 % had mucosal thickening, 19 % had partial opacification, 5 % had total opacification, and 12 % had polypoidal mucosal thickening. Right and left maxillary sinus pathologies were approximately twice as prevalent in patients with periapical pathology in at least one maxillary posterior tooth. Periapical pathologies in the right maxillary first molar and left maxillary first and second molars significantly increased the risk of maxillary sinus pathology with odds ratios of 2.53, 1.83, and 3.12, respectively.

Conclusions

Odontogenic maxillary sinus pathologies were present in >50 % of the study population. Periapical pathologies in the maxillary first and second molar teeth significantly increased maxillary sinus pathologies.

     

Comparison of periodontal evaluation by cone-beam computed tomography,and clinical and intraoral radiographic examinations

Objectives

Cone-beam computed tomography (CBCT) has been widely used in many fields of dentistry. However, little is known about the accuracy of CBCT for evaluation of periodontal status. The objective of this study was to compare and correlate periodontal assessments among CBCT, clinical attachment loss (CAL) measurement, and periapical (PA)/bitewing (BW) radiography.

Methods

Eighty patients (28 males, 52 females; age range, 19–84 years) from the University of Texas School of Dentistry at Houston were evaluated retrospectively. Measurements were taken on the central incisors, canines, and first molars of the right maxilla and left mandible. CAL was extracted from periodontal charts. The radiographic distance from the cementum–enamel junction (CEJ) to the alveolar crest was measured for tooth mesial and distal sites on PA/BW and CBCT images using MiPacs software and Anatomage Invivo software, respectively. One-way ANOVA and Pearson analysis were performed for statistical analyses.

Results

The CEJ–crest distances for CBCT, PA/BW, and CAL were 2.56 ± 0.12, 2.04 ± 0.12, and 2.08 ± 0.17 mm (mean ± SD), respectively. CBCT exhibited larger values than the other two methods (p < 0.05). There were highly significant positive correlations among CBCT, PA/BW, and CAL measurements at all examined sites (p < 0.001). The Pearson correlation coefficient was higher for CBCT with CAL relative to PA/BW with CAL, but the difference was not significant (r = 0.64 and r = 0.55, respectively, p > 0.05).

Conclusions

This study validates the suitability of CBCT for periodontal assessment. Further studies are necessary to optimize the measurement methodology with CBCT.

     

Cone-beam computed tomography for assessment of dens invaginatus in the Polish population

Objectives

There are many developmental variations in the permanent dentition. Dens invaginatus can be recognized on many dental X-rays of affected patients, but not every image allows for assessment of the type of malformation. The aim of the present study was to assess the presence of dens invaginatus with radiological features using cone-beam computed tomography (CBCT).

Methods

CBCT images of 33 patients were evaluated. Age, sex, side, lateralization, occurrence in a particular group of teeth, type of invagination, differentiation, and the consequences of these factors were analyzed.

Results

Forty-one teeth with dens invaginatus met the inclusion criteria for this evaluation. Females were affected more frequently than males (57.6 vs. 42.4%, respectively). The patients’ age ranged from 7 to 40 years, and the occurrence of dens invaginatus peaked from age 9 to 13 years. In total, 92.7% of affected teeth were present in the maxilla, more often unilaterally (75.8%) than bilaterally (24.2%). The most frequent tooth with dens invaginatus was the maxillary lateral incisor (53.7% of affected teeth). Almost two-thirds (63.4%) of affected teeth were found on the left side and 36.6% were found on the right. The tooth anatomy was distorted within the crown and root. Dens invaginatus sometimes affected other surrounding teeth and reduced their esthetics.

Conclusions

The obtained data indicate that CBCT examination is an essential tool in assessing dens invaginatus and can guide dental practitioners in treating patients who exhibit characteristic features of this disorder. CBCT allows the clinician to distinguish the type of anomaly.

     

Three-dimensional evaluation of angular,linear, and resorption features of maxillary impacted canines on cone-beam computed tomography

Objectives

The aim of this study was to evaluate the localization, angulation, and resorption features of maxillary impacted canines on cone-beam computed tomography (CBCT).

Methods

This retrospective study examined the CBCT scans of 140 maxillary impacted canines in 102 patients (43 males, 59 females; mean age: 16.25 ± 6.31 years). The following impacted canine-related parameters were analyzed on the CBCT images: impaction side; location; root resorption levels of adjacent teeth; occlusal plane and midline distances of impacted canines; and angulations of impacted canines to midline, lateral incisor, and occlusal plane.

Results

Bilateral canine impaction was found in 38 subjects, and unilateral canine impaction was present in 64 subjects. Severe resorption was found in 14 canines. There were no significant differences between the occlusal plane and midline distances to the impacted canine cusp tip and root apex (p > 0.05). The midline angulation of right maxillary impacted canines was significantly higher than that of left maxillary impacted canines (p < 0.05), while the occlusal plane angulation of left maxillary impacted canines was significantly higher than that of right maxillary impacted canines (p < 0.05).

Conclusions

Maxillary canine impaction was more frequently seen in female subjects than in male subjects. Lateral incisors were more frequently affected than first premolars, and slight resorption was more frequently seen in adjacent teeth. CBCT assessment of maxillary impacted canines can provide accurate measurements of angular, linear, and resorption parameters.

     

Facial fractures caused by less-lethal rubber bullet weapons: case series report and literature review

Purpose

The present study aims to describe three cases of patients inflicted by rubber bullets with severe facial fractures.

Methods

In addition, a review of English-language literature involving facial fractures by rubber bullets from 1975 to 2016 was performed.

Results

This current study demonstrated that the use of the LLRBW is unsafety even when applied by police enforcements exclusively.

Conclusions

Management of facial fractures caused by LLRBW is done in a usual manner with closed or open reduction associated with bone mini-plates or reconstruction plates when indicated. Special initial wound care should be done to avoid secondary infection and additional procedures.

     

CBCT-based bone quality assessment in decompression of large odontogenic cystic lesions

Objectives

Bone quality comprises bone mineral density and trabecular microstructure. The aim of this study was to explore the effectiveness of cone-beam computed tomography (CBCT) in evaluating bone quality of large odontogenic cystic lesions after decompression using CBCT and BoneJ software, and to determine whether secondary definitive surgery can be guided using CBCT data.

Methods

Twenty-seven patients with large odontogenic cystic lesions treated by decompression were evaluated by CBCT. Medical history and perioperative details were analyzed.

Results

The \(\Delta\)CT values for all patients with cystic lesions decreased after decompression, with no differences for age, sex, and histology (p?>?0.05). Bone volume fraction and trabecular number of new cancellous bone (0.012%, 0.17/mm³) were lower than those of normal cancellous bone (0.189%, 0.47/mm³) (p?<?0.05), while new cancellous bone trabecular separation (11.344?±?2.556 mm) was stronger than normal cancellous bone trabecular separation (4.833?±?2.232 mm) (p?<?0.05). There were no differences in trabecular thickness between new cancellous bone (3.812?±?1.593 mm) and normal cancellous bone (4.598?±?3.573 mm) (p?=?0.746). The \(\Delta\)CT values of five patients with favorable osteogenesis were ??72, ?86, ??86, ?47, and ??55, those of three patients with moderate osteogenesis were ??107, ?120, and ??71, and those of two patients with poor osteogenesis were ??165 and ??127 during secondary definitive surgery.

Conclusions

CBCT is considered beneficial for evaluating bone quality of large odontogenic cystic lesions after decompression, while providing potentially useful information for referral to secondary definitive surgery.