Cone Beam Computed Tomographic Evaluation of Mandibular Asymmetry in Patients with Cleft Lip and Palate

Mandibular condyle volumes are associated with facial asymmetry in patients with cleft lip and palate: A retrospective cohort study

This study compares condylar volumetric asymmetry and facial asymmetry in patients with cleft lip and/or palate (CLP) and controls. The mandibular condyle is important to facial growth, but its role in facial asymmetry for those with CLP has not been described. Condylar volumes and mandibular asymmetry were retrospectively calculated using Mimics Version 23.0 (Materialise, Leuven, Belgium) from patients with CLP undergoing computed tomography (CT) imaging and a cohort of controls. A total of 101 participants, 60 with CLP and 41 controls, had mean condylar volumetric asymmetry of 16.4 ± 17.4 % (CLP) and 6.0 ± 4.0 % (controls) (p = 0.0002). Patients with CLP who had clinically significant chin deviation (>4 mm) had more asymmetric condyles than those without significant chin deviation (p = 0.003). The chin deviated toward the smaller condyle in patients with facial asymmetry more often than in patients without facial asymmetry (81 % vs. 62 %, p = 0.033). While controls had some degree of condylar asymmetry, it tended to be milder and not associated with facial asymmetry. There is a greater degree of condylar volumetric asymmetry in patients with CLP compared to individuals in the general population. Clinically significant facial asymmetry in CLP is associated with a higher degree of condylar asymmetry, with the facial midline deviating toward the smaller condyle.

The Use of Clear Aligners in Multi-Segmental Maxillary Surgery: A Case-Control Study in Cleft Lip and Palate and Skeletal Class III Patients

Background: Maxillary hypoplasia and mandibular asymmetry may be corrected with orthognathic surgery after growth completion. For most stable results, some cases may require segmental Le Fort I osteotomies. Unfortunately, Invisalign's software (6.0 version) still has some inherent limitations in predicting outcomes for complex surgeries. This study explores the potential of aligners, particularly in multiple-piece maxillary osteotomies in both cleft and non-cleft patients. Method: Thirteen patients who underwent pre-surgical treatment with Invisalign were retrospectively matched in terms of diagnosis, surgical procedure, and orthodontic complexity with thirteen patients treated using fixed appliances. Virtual curves following the lower arch were employed to guide the correct pre-surgical positions of the upper teeth with a simple superimposition technique. The amount of impressions required in both groups to achieve satisfactory pre-surgical alignment of the segmented arches was compared. Results: one or no refinement phases were needed in the Invisalign group to reach an acceptable pre-surgical occlusion, while the amount of pre-surgical impressions needed to reach adequate coordination with fixed appliance treatment was slightly higher (p > 0.05). Conclusions: it appears that clear aligner could serve as an effective treatment for individuals necessitating segmental Le Fort I osteotomies when aided by the suggested simple superimposition approach.

Assessment of mandibular asymmetry in different skeletal malocclusions and vertical patterns in adult individuals: A cone-beam computed tomography study

OBJECTIVES

The study aims to measure the mandibular condylar height (CH), ramus height (RH), total height (CH+RH), asymmetry index, and condylar volume (Cvol) in individuals with different anteroposterior and vertical skeletal discrepancies.

MATERIALS AND METHODS

The study sample consisted of 131 subjects (60 females and 71 males) with a mean age of 35.06 ± 12.79 years. Pre-existing CBCT images were divided into groups according to the anteroposterior and vertical skeletal discrepancies. The investigator analyzed the data using t-tests to assess the mandibular bilateral sides of the individuals and gender differences. The mean difference between groups was determined using a one-way analysis of variance (ANOVA). The Chi-square test was used to study the association between the asymmetry index and groups.

RESULTS

Each individual's bilateral sides exhibited statistically significant differences in CH, RH, and Cvol (P = 0.033, P = 0.039, P = 0.005, respectively), but not in CH+RH (P = 0.458). There were, however, statistically significant gender differences in CH+RH (P < 0.001). Skeletal Class III and hypodivergent groups revealed the highest linear and volumetric values compared to other groups. The asymmetry index was increased in CH (P = 0.006) and Cvol (P = 0.002) in skeletal Class II subjects.

CONCLUSIONS

Significant differences in CH, RH, and Cvol were found on the right and left sides of the same individual. This study found increased linear and volumetric values in males, skeletal Class III, and hypodivergent subjects. Class II individuals had an increased CH and Cvol asymmetry index. This study highlights in-depth knowledge of mandibular asymmetry, which is extremely important to achieve an accurate diagnosis and provide the best treatment outcome.

Evaluation of the Prevalence of Atherosclerosis Within the Course of Internal Carotid Artery in Cone Beam Computed Tomography Images

The aim of the present study was to retrospectively evaluate the gender-related and age-related prevalence and severity of calcifications within the segments of the internal carotid artery in cone beam computed tomography (CBCT). By using a documented visual scale, out of 400 CBCT examinations a total of 304 CBCT scans of adult patients over 40 years old were evaluated as to the prevalence and severity of intracranial calcifications within the segments of the internal carotid artery. Calcifications were found in 117 CBCT scans. These calcifications were detected along the extracranial (C1: 53%), petrous (C2: 22.2%), Lacerum (C3:27%), cavernous (C4: 94%), and ophthalmic-clinoid (C5/C6: 65%) segments. The Friedman test showed significant differences in the severity of calcifications among the internal carotid artery segments. The McNemar test showed no significant differences between calcifications on the right or left side segments. The Chi square test showed no significant differences in the prevalence of calcifications between men and women; it also showed that the prevalence of calcifications increased with increase in age (P < 0.05). In this study, the frequency and severity of calcifications decreased throughout the C4, C5/C6, and C1 segments in a descending order; moreover, an increased incidence of calcifications by increase in age was documented irrespective of gender.

Evaluation of associations between condylar morphology, ramus height, and mandibular plane angle in various vertical skeletal patterns: a digital radiographic study

Background

To evaluate condylar morphology, ramus height, and asymmetry indexes in patients with different vertical skeletal patterns and to determine the association between condylar and ramal measurements with the mandibular plane angle.

Methods

Dental panoramic radiographs of 60 patients with different skeletal patterns were evaluated. According to the cranial base (Sella-Nasion)-mandibular plane (SN-MP) angle, the patients were divided into three groups: normal angle (NA), low angle (LA), and high angle (HA). The condylar area, condylar perimeter, condylar heights, and ramus height were measured, and the asymmetry index value of each measurement was calculated. A one-way analysis of variance as well as a post hoc Tukey and Kruskall-Wallis tests were used to determine intergroup differences. Pearson’s correlation coefficient was used to determine the relationship between all measurements and SN-MP.

Results

The intergroup comparison of condylar area, condylar perimeter, condylar heights, and ramus height measurements showed that the patients in the LA group have statistically significantly greater values compared to those in the HA group. A statistically significant difference was detected between the NA and LA groups only in the condylar area measurements. There was no statistical difference only in the ramus height measurements between the NA and HA groups. Asymmetry index values of the groups were similar. The negative correlations were found between all measurements and the SN-MP angle.

Conclusion

HA individuals have lower ramus heights and smaller condylar morphologies than NA and LA individuals. In addition, as the SN-MP angle increases, the condyle dimensions and ramus height decrease, and this is a clinically important finding.

Condylar Changes after Maxillary Expansion in Children with Cleft Lip and Palate—A Three-Dimensional Retrospective Study

Background: The presence of posterior crossbite can trigger aesthetic and functional changes as mandibular asymmetry in individuals, contributing to asymmetrical muscle function. Mandibular asymmetry and respective condyle adaptation may be an etiological factor in temporomandibular disorder. This study aims to evaluate the effects of maxillary expansion on the position and angulation of the condyles as well as the intercondylar distance in children with cleft lip and palate. Methods: Twenty-five individuals with cleft lip and palate who underwent maxillary expansion were selected. Condylar changes were evaluated by cone beam computed tomography using the Pullinger and Hollender formula. To determine the statistically significant differences between the variables, the Student t-test and the Benjamini–Hochberg correction method for multiple comparisons were used. Results: No statistically significant differences between angulation and condylar position before and after maxillary expansion were found. The intercondylar distance tended to increase in growing individuals with cleft lip and palate after maxillary expansion. Conclusions: Intercondylar distance shows a tendency to increase after expansion regardless of the cleft phenotype. No differences were found in angulation and condylar position with the changes in occlusion resulting from maxillary expansion.

A Radio-Odontometric Analysis of Sexual Dimorphism in First Molars Using Cone-Beam Computed Tomography

OBJECTIVE

Different techniques for sex prediction are developed and used in the forensic medicine field. One of these methods is based on the teeth morphometry. The aim of the present study was to evaluate the degree of sex determination of the maxillary and mandibular first molar teeth in cone beam computed tomography images.

METHOD AND MATERIALS

This study was carried out on cone beam computed tomography images of 100 men and 100 women with a mean age of 21.28 ± 2.47 years. The roof, floor and height of pulp chamber, as well as marginal enamel thickness and dentin thickness at the height of contour, tooth width, and crown length were measured. Student t test and discriminant analysis were applied to assess the differences in the measured parameters between men and women.

RESULTS

According to the present study, the maxillary first molar was more dimorphic than the mandibular teeth. The accuracy of sex identification of mandibular and maxillary first molar tooth was 84% and 77%, respectively. The mesiodistal measured variables were more accurate in sexual differentiation than the buccolingual ones. For sex differentiation, the most dominant variables for maxillary and mandibular first molar teeth were crown height and dentin thickness, respectively.

CONCLUSIONS

The first molar tooth showed an acceptable level of sex determination accuracy based on the odontometric measurements.

Correlations Between Mandibular Asymmetries and Temporomandibular Disorders: A Systematic Review

Objective

This systematic review aimed to investigate the correlation between mandibular asymmetry and temporomandibular disorders (TMDs).

Materials and Methods

A systematic search of the published literature was performed in electronic databases such as PubMed (MEDLINE), Scopus, Web of Science, Cochrane, Google Scholar, Clinicaltrials.gov, and Saudi Digital Library. Gray literature was searched through System for Information on Grey Literature through OpenGrey. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was followed in the investigation. The focussed question according to PICO format was: "does the mandibular asymmetry contribute to temporomandibular disorders"? Eligibility criteria included clinical trials (CTs), observation studies, cross-sectional and cohort studies in English that investigated mandibular asymmetries and TMD among patients. Blind and duplicate study selection, data extraction, and risk of bias assessment were carried out.

Results

The initial search resulted in 1906 articles, of which 11 (8 CTs, 1 cross-sectional, 1 retrospective, and 1 observational) studies were selected for qualitative synthesis after fulfilling the eligibility criteria.

Conclusion

Most of the studies included in this review showed either very high risk or high risk of bias. Despite the low certainty of evidence, the current study indicated a likely relationship between mandibular asymmetries and TMDs.

A cloud-fog software architecture for dental CBCT dose monitoring using the DICOM structured report: Automated establishment of DRL

PURPOSE

The diagnostic reference level (DRL) has been established to optimize the diagnostic methods and reduce radiation dose during radiographic examinations. The aim of this study was to present a completely new solution based on Cloud-Fog software architecture for automatic establishment of the DRL values during dental cone-beam computed tomography (CBCT) according to digital imaging and communications in medicine (DICOM) structured reports.

METHODS AND MATERIALS

A Cloud-Fog software architecture was used for automatic data handling. This architecture used the DICOM structured reports as a source for extracting the required information by fog devices in the imaging center. These devices transferred the derived information to the cloud server. The cloud server calculated the value of indication-based DRL in dental CBCT imaging based upon the parameters and adequate quantities of the absorbed dose. The feedback of DRL value was continuously announced to the imaging centers in 6 phases. In each phase, the level of the dose was optimized in imaging centers.

RESULTS

The DRL value was established for 5-specific indications, including third molar teeth (511 mGy.cm²), implant (719 mGy.cm²), form and position anomalies of the tooth (408 mGy.cm²), dentoalveolar pathologies (612 mGy.cm²), and endodontics (632 mGy.cm²). The determination of the DRL value in each phase revealed a downward trend until stabilization.

CONCLUSION

The new solution presented in this study makes it possible to calculate and update the DRL value nationally and automatically among all centers. Also, the results showed that this approach is successful in establishing stabilized DRL values.

Evaluation of Maxillary Sinus Characteristics in Patients With Cleft Lip and Palate Using Cone Beam Computed Tomography

OBJECTIVES

The detection of anatomical variation impairments in patients with cleft lip and palate (CLP) is crucial in combined orthodontic and maxillofacial surgical treatments. Therefore, this study aimed at evaluating the anatomical maxillary sinus characteristics, nasal septum deviation (NSD), and mucosal thickening of the maxillary sinus in patients with CLP using cone beam computed tomography (CBCT).

DESIGN

The CBCT images were classified into 3 groups of unilateral cleft lip and palate (UCLP; n = 40), bilateral cleft lip and palate (BCLP; n=14), and noncleft (control; n = 54). Subsequently, the maxillary sinus linear dimensions were assessed. Height, width, depth, infundibulum height, and ostium width were assessed as quantitative measures, whereas nasal septum deviation and mucosal thickening were assessed as qualitative measures. One-way analysis of variance and χ² tests were utilized to identify any significant differences among the groups regarding the aforementioned variables.

RESULTS

Significant differences were observed among the groups regarding maxillary sinus height and depth, NSD, and mucosal thickening. Moreover, UCLP and BCLP groups showed higher incidence of NSD and mucosal thickening. However, the size of maxillary sinus height and depth was lower in the UCLP and BCLP groups.

CONCLUSION

The results showed that BCLP and UCLP groups obtained lower maxillary sinus height and depth compared to the control group. On the other hand, incidence of the NSD and mucosal thickening was significantly higher in UCLP and BCLP groups than those in the control group.

Vertical Facial Skeletal Asymmetry and Occlusal Cant Relationship in Patients With Unilateral Cleft Lip and Palate

OBJECTIVE

To evaluate the maxillary and mandibular vertical skeletal asymmetries, and the correlation between these asymmetries and occlusal cant in patients with unilateral cleft lip-palate (UCLP).

METHODS

Anteroposterior radiographs of 25 patients with UCLP (UCLP group, mean age: 20.98 ± 4.88 years) and 25 subjects without cleft (control group, mean age: 19 ± 2.86 years) were included. Independent samples t test, Mann-Whitney U test and Pearson correlation analysis were performed based on linear and angular measurements.

RESULTS

Lower facial horizontal asymmetry did not show statistically significant difference between the UCLP and control groups. However, vertical asymmetry of (a) the lateral cranial base (P = .014), (b) the nasomaxillary region (P < .001), (c) the maxillary dentoalveolus (P = .001), and (d) the lower face (P = .038) were all found to be significantly greater in UCLP group. The occlusal cant angle was also significantly greater in patients with UCLP compared to the controls (P = .016). While the occlusal cant angle was found to be correlated with the vertical asymmetry of the occlusal cant (r = 0.931, P < .001), maxillary cant angle was found to be correlated with the vertical asymmetry of the maxillary dentoalveolus (r = 0.655, P < .001).

CONCLUSIONS

There was no correlation between the occlusal cant and the vertical and horizontal skeletal asymmetries. Vertical asymmetries of the lower face and the medial cranial base were negatively correlated with the horizontal lower facial asymmetry.

CBCT in orthodontics: a systematic review on justification of CBCT in a paediatric population prior to orthodontic treatment

BACKGROUND

Taking into account radiation doses, safety, and protection, we highlighted the features in which cone-beam computed tomography (CBCT) can offer an advantage compared to the conventional two-dimensional imaging in paediatric dentistry before orthodontic treatment.

OBJECTIVE

The aim of this article was to conduct a systematic review to assess the diagnostic efficacy of CBCT in the paediatric population at a pre-orthodontic phase.

SEARCH METHODS

MEDLINE via PubMed was searched to identify all peer-reviewed articles potentially relevant to the review until 1 July 2018. Relevant publications were selected by two reviewers independently.

SELECTION CRITERIA

The literature selection for this systematic review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was based on predetermined inclusion criteria.

DATA COLLECTION AND ANALYSIS

Data were collected on overall study characteristics and examination characteristics of the selected studies. Methodological quality of the selected studies was evaluated. Original studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. Thereafter, levels of evidence were obtained according to Grading of Recommendations Assessment, Development and Evaluation criteria.

RESULTS

As a result of the QUADAS assessment, a total of 37 articles were included in the protocol. Following a proper protocol, CBCT was regarded as a reliable tool for assessment and management of impacted canine and root fracture. It provided a better evaluation of normal and pathological condylar shape and volume. CBCT was a superior choice for pre-surgical diagnostic applications in cleft lip and/or palate over a medical computed tomography based on its lower radiation exposure, shorter investigation time, and low purchase costs.

CONCLUSIONS

CBCT is justified only in those cases where conventional radiography fails to provide a correct diagnosis of pathology. Therefore, it cannot be regarded as a standard method of diagnosis. CBCT imaging may also be justified when it positively affects treatment options or provides treatment optimization.

REGISTRATION

None.

CONFLICT OF INTEREST

None to declare.

Outcome of facial contour asymmetry after conventional two-dimensional versus computer-assisted three-dimensional planning in cleft orthognathic surgery

Computer-assisted 3D planning has overcome the limitations of conventional 2D planning-guided orthognathic surgery (OGS), but difference for facial contour asymmetry outcome has not been verified to date. This comparative study assessed the facial contour asymmetry outcome of consecutive patients with unilateral cleft lip and palate who underwent 2D planning (n = 37)- or 3D simulation (n = 38)-guided OGS treatment for correction of maxillary hypoplasia and skeletal Class III malocclusion between 2010 and 2018. Normal age-, gender-, and ethnicity-matched individuals (n = 60) were enrolled for comparative analyses. 2D (n = 60, with 30 images for each group) and 3D (n = 43, with 18 and 25 images for 2D planning and 3D simulation groups, respectively) photogrammetric-based facial contour asymmetry-related measurements were collected from patients and normal individuals. The facial asymmetry was further verified by using subjective perception of a panel composed of 6 blinded raters. On average, the facial contour asymmetry was significantly (all p < 0.05) reduced after 3D virtual surgery planning for all tested parameters, with no significant differences between post-OGS 3D simulation-related values and normal individuals. No significant differences were observed for pre- and post-OGS values in conventional 2D planning-based treatment, with significant (all p < 0.05) differences for all normal individuals-related comparisons. This study suggests that 3D planning presents superior facial contour asymmetry outcome than 2D planning.

Photogrammetric Evaluation of Soft Tissue Profile and Frontal Photographs in Repaired Bilateral Cleft Lip and Palate

OBJECTIVE

To evaluate the soft tissue profile and frontal photographs of 8- to 12-year-old patients with repaired complete bilateral cleft lip and palate (BCLP).

METHODS

The profile and frontal photographs obtained from 31 nonsyndromic BCLP children (aged 8-12 years: 14 boys and 17 girls) were analyzed and compared with an age- and sex-matched normal population (18 boys and 32 girls). In each patient, 12 soft tissue angular and proportional parameters on the frontal photograph and 12 angular parameters for the profile photographs were developed and measured. Student t test was used to compare the mean value of the parameters between both sexes.

RESULTS

In the frontal view, there was a significant difference between the 2 study groups in the facial symmetry angle (P < .001), lower facial height proportion (P < .001), upper lip proportion (P < .001), and interalar width/distance between the inner canthus of the eyes (P < .001). In the profile view, there was a significant difference between the control group and the patients with cleft lip and palate in terms of nasofrontal angle (P < .001), nasal angle (P < .001), angle of the inferior facial third (P = .032), head position angle (P < .001), facial convexity angle (P < .001), total facial convexity angle (P < .001), and vertical nasal angle (P < .001).

CONCLUSION

In comparison with the normal population, the face of patients with repaired BCLP showed several soft tissue deformities, especially in the nasofrontal region, even after a surgical repair.

Breaking Symmetry: A Quantitative Analysis of Facial Skeleton Disharmony in Children Born with Bilateral Cleft Lip and Palate

Bilateral cleft lip and palate (BCLP) occurs when craniofacial precursors fail to form or fuse properly during development. The aim of this retrospective, cross-sectional investigation was to quantify directional asymmetry (DA) of the facial skeleton of children born with Veau Class IV nonsyndromic BCLP. To accomplish this goal, coordinate values of anatomical landmarks were acquired from three-dimensional cone beam computed tomographic images of the craniofacial skeleton of middle- to late-aged children born with BCLP and age- and sex-matched controls and used to compare patterns of asymmetry variation. Multivariate analyses revealed different patterns of DA variation across samples and identified approximately 30% of DA measures as significantly different. Magnitudes of statistically significant linear distances differ in the craniofacial region, with most smaller DA differences located near the orbits and frontal bone, while larger differences were localized mostly to the midface, alveolar ridge, and nasal borders. Generally, areas of the craniofacial skeleton derived from the maxillary and nasal prominences demonstrated the highest magnitudes of DA. The methods and results presented will be useful to biomedical researchers when identifying the extent to which patients with BCLP diverge from typical developmental expectations. Quantifying DA and assessing local differences across the craniofacial complex can aid medical practitioners when developing treatments to improve BCLP surgical algorithms and outcomes. Anat Rec, 302:1726-1732, 2019. © 2019 American Association for Anatomy.

A cone beam computed tomographic evaluation of the size of the sella turcica in patients with cleft lip and palate

OBJECTIVE

Changes in the size of the sella turcica are frequently related to pathologies and syndromes. The aim of this was to compare the sella turcica dimensions in patients with unilateral and bilateral cleft lip and palate and non-cleft subjects.

METHODS

Cone beam computed tomography (CBCT) images of three groups consisted of 20 patients with unilateral cleft lip and palate; 20 patients with bilateral cleft lip and palate and a control group consisting of 20 non-cleft subjects were the research population in this pilot study. The sella turcica linear dimensions in terms of length, depth and diameter were measured for all subjects. One-way ANOVA test was used to determine any significant differences among the three groups for the measured parameters.

RESULTS

The length, depth and diameter of sella turcica were found to be significantly smaller in the unilateral and bilateral groups compared with the normal age and gender matched group. No significant differences were found in the measured variables between the unilateral and bilateral cleft patients.

CONCLUSION

CBCT images showed a greater likelihood of abnormal sella turcica dimensions in patients with unilateral and bilateral cleft lip and palate. Therefore, the sella turcica dimensions may have an intrinsic relationship to the cleft condition.