Three-dimensional evaluation of midfacial asymmetry in patients with nonsyndromic unilateral cleft lip and palate by cone-beam computed tomography

Midface asymmetry in non-syndromic unilateral cleft lip-palate: a retrospective cbct analysis

Purpose

The aim of this study was to determine the relationship between the zygomaticomaxillary complex (ZMC) and infraorbital foramen region (IFR) with facial symmetry in patients with unilateral cleft lip and palate (UCLP) using cone beam computed tomography (CBCT).

Materials and methods

In this retrospective study, CBCT images of 30 non-syndromic UCLP patients were included, along with 30 age- and sex-matched control individuals. ZMC symmetry was evaluated in the axial section by comparing the right and left sides. Similarly, symmetry in the IFR was assessed in the coronal section. The significance level was set at p<0.05 for statistical analysis.

Results

The study group comprised 12 female and 18 male patients, with ages ranging from 10 to 18 years (mean age 14.1 years). Both ZMC and IFR measurements were significantly lower on the cleft sides of the study group compared to both the non-cleft sides of UCLP patients and the control group (p<0.001, p=0.022, and p=0.036, respectively). Furthermore, IFR measurements were significantly lower in the control group compared to the non-cleft sides of the study group (p=0.04).

Conclusion

This study demonstrated that individuals with UCLP exhibit asymmetry in both the ZMC and the IFR. These findings suggest a negative impact on facial aesthetics.

Three-dimensional nasal asymmetry analysis between adolescence and adulthood in postoperative patients with unilateral cleft lip and palate using computed tomography

AIM

To investigate the differences of the nasal soft and hard tissue asymmetry in postoperative patients with unilateral cleft lip and palate (UCLP) between adolescence and adulthood, and to explore the correlation of nasal soft and hard tissue asymmetry.

METHODS

CT data from 47 repaired UCLP patients were included and divided into two groups:1. adolescent group: 23 patients (15 males, 8 females; age: 10-12 years old). 2. adult group: 24 patients (16 males, 8 females; age:18-32 years old). The three-dimensional asymmetry in nasal soft and hard tissues was analyzed. Additionally, the correlation between nasal soft and hard tissue asymmetry was also analyzed.

RESULTS

Both the adolescent group and adult group showed asymmetries in nasal soft and hard tissues. Compared to the adolescent group, the adult group had a significantly increased horizontal asymmetry of nasal soft tissues Sbal (P < 0.05). Furthermore, the sagittal asymmetry of soft tissue Glat (P < 0.05), Sbal (P < 0.001), Sni (P < 0.001) and hard tissue LPA (P < 0.05) also increased significantly. In the adult group, there were more landmarks with a correlation between the asymmetry of nasal hard tissue and soft tissue compared to the adolescent group. There were moderate to strong correlations between nasal hard and soft tissue symmetries in the horizontal and sagittal directions (0.444 < r < 764), but no correlation in the vertical direction in the adult group (P > 0.05).

CONCLUSIONS

The asymmetry of nasal soft and hard tissues in patients with repaired UCLP becomes more apparent in the horizontal and sagittal dimensions from adolescence to adulthood. The correlation between the asymmetry of nasal hard tissue and soft tissue becomes stronger in the horizontal and sagittal dimensions. These factors should be taken into account when performing treatment for repaired UCLP patients in adolescence and adulthood.

Correlation between Cleft Width and Adjacent Teeth Inclination in Patients with Unilateral Cleft Lip and Palate Using CBCT: A Retrospective Study

OBJECTIVES

To evaluate buccolingual and mesiodistal inclination of cleft-adjacent maxillary permanent central incisors (U1) and canines (U3) in patients with unilateral cleft lip and palate (UCLP) in the late mixed dentition and to investigate the correlation between the alveolar cleft width and cleft-adjacent teeth inclination using cone beam computed tomography (CBCT).

DESIGN

Observational cross-sectional retrospective study.

SETTING

Department of Orthodontics, Hama University Dental School.

PATIENTS

32 patients with UCLP (22 boys, 10 girls; mean age = 10.53 ± 1.51 years).

MAIN OUTCOME MEASURE

Buccolingual and mesiodistal inclination of maxillary central incisors and canines were measured on both sides. Then, the cleft and non-cleft sides were compared using the Wilcoxon signed-rank test. Pearson's correlation was used to explore the association between the alveolar cleft width and cleft-adjacent U1 and U3 buccolingual and mesiodistal inclination.

RESULTS

The cleft-adjacent central incisors were significantly inclined lingually and distally compared with their non-cleft antimeres (P = .003, P < .001, respectively). The cleft-adjacent canines were significantly inclined buccally and mesially compared with their non-cleft antimeres (P < .001, for both). A positive correlation was found between the buccolingual inclination of cleft-adjacent U1 and the alveolar cleft width (r = 0.49, P = .004).

CONCLUSIONS

Patients with UCLP demonstrated a significant lingual and distal inclination of cleft-adjacent U1 and a significant buccal and mesial inclination of cleft-adjacent U3. The buccolingual inclination of cleft-adjacent U1 tends to increase with increasing the alveolar cleft width; however, the correlation was weak.

One-Jaw versus Two-Jaw Orthognathic Surgery for Patients with Cleft: A Comparative Study Using 3D Imaging Virtual Surgical Planning

Whether a one-jaw or two-jaw design is used in orthognathic surgery for patients with cleft remains varied and controversial. This study aimed to compare the two approaches using 3-dimensional imaging surgical simulation. This study was conducted on 41 consecutive patients with complete unilateral cleft lip and palate treated in the craniofacial center. All patients had original two-jaw virtual planning and orthognathic surgery. Simulation of one-jaw LeFort I surgery was performed using the same final dental occlusion on 3-dimensional images. Cephalometric data and asymmetry index were collected and compared among the designs. Average advancement of the maxilla was 7.46 mm in one-jaw and 4.80 mm in two-jaw design. SNA, SNB, and A-N perpendicular were significantly greater and close to normative data in the one-jaw design. ANB angles were similar in both designs. The anterior and posterior occlusal plane cants, the deviation of midline landmarks, and the asymmetry index were more improved in the two-jaw approach. It is concluded that the two-jaw cleft orthognathic surgery could significantly improve facial midline and symmetry compared with the one-jaw approach. However, the two-jaw surgery with mandibular setback produced less protrusive facial contour although a harmonious relationship between the maxilla and mandible was achieved.

Assessment of the asymmetry of the lower jaw, face, and palate in patients with unilateral cleft lip and palate

Background:

This study aimed to assess the asymmetry of the lower jaw, face, and palate in patients with unilateral cleft lip and palate (UCLP) using photography, cone-beam computed tomography (CBCT), and digitized three-dimensional casts.

Methods:

This case–control study was conducted on photographic, CBCT, and digital cast records of 14 UCLP patients and 24 healthy controls between 10 and 16 years. Totally, 65 variables were measured on photographs, CBCT scans, and on digitized casts. Measurements were compared between the two groups and within each group between the two sides. For easier measurement, in patients who had right side CLP, the cleft was transferred to the left side and in subjects without cleft, mild chin deviation was transferred to the left side.

Results:

The anteroposterior dimensions of the two condyles in the UCLP group were greater than those in the control group, while the mediolateral dimensions of the left condyle and ramus height, mandibular body length, and total length of the mandible in the control group were greater than those in the UCLP group. Right ocular, nasal, and angular variables were greater in the UCLP group. Other variables except for the palatal width from the right canine to midline were greater in the control group.

Conclusion:

Our findings highlighted the presence of asymmetry in the nasal and palatal areas in patients with UCLP while these patients had no significant difference with healthy controls in the relationship of condyles with the temporomandibular fossa.

Correlation between alveolar cleft volume and alveolar bone quality in patients with unilateral cleft lip and palate: A cone-beam computed tomography study

OBJECTIVES

This study aimed to determine the correlation between alveolar cleft volume and fenestration and dehiscence in the adjacent alveolar bone in patients with unilateral cleft lip and palate (UCLP) using cone-beam computed tomography (CBCT) sections.

MATERIALS AND METHODS

In this descriptive, cross-sectional study, CBCT scans of 68 non-syndromic patients with UCLP aged between 6 and14 years were selected. All patients were treated in Iran and had undergone lip and palate repair surgery within the first 3 to 18 months after birth. CBCT scans had been taken after orthodontic expansion and prior to alveolar bone grafting surgery. Cleft volume, fenestration and dehiscence were assessed using Mimics software. Data were analyzed using independent t-test, Kruskal-Wallis test, Spearman's correlation coefficient and logistic regression model.

RESULTS

The mean alveolar cleft volume was 628.66±172.84 mm³. There was a significant negative correlation between cleft volume and fenestration (P<0.001). Also, there was a significant positive correlation between cleft volume and dehiscence (P<0.001) in the adjacent bone.

CONCLUSION

The Mimics software can be successfully used to estimate the cleft volume prior to surgical procedures in UCLP patients. The results suggest that the alveolar cleft volume can be used as an aid to assess the periodontal condition of adjacent teeth. The cleft volume has a negative and positive correlation with fenestration and dehiscence respectively.

3D morphometric quantification of maxillae and defects for patients with unilateral cleft palate via deep learning-based CBCT image auto-segmentation

OBJECTIVE

This study aimed to quantify the 3D asymmetry of the maxilla in patients with unilateral cleft lip and palate (UCP) and investigate the defect factors responsible for the variability of the maxilla on the cleft side using a deep-learning-based CBCT image segmentation protocol.

SETTING AND SAMPLE POPULATION

Cone beam computed tomography (CBCT) images of 60 patients with UCP were acquired. The samples in this study consisted of 39 males and 21 females, with a mean age of 11.52 years (SD = 3.27 years; range of 8-18 years).

MATERIALS AND METHODS

The deep-learning-based protocol was used to segment the maxilla and defect initially, followed by manual refinement. Paired t-tests were performed to characterize the maxillary asymmetry. A multiple linear regression was carried out to investigate the relationship between the defect parameters and those of the cleft side of the maxilla.

RESULTS

The cleft side of the maxilla demonstrated a significant decrease in maxillary volume and length as well as alveolar length, anterior width, posterior width, anterior height and posterior height. A significant increase in maxillary anterior width was demonstrated on the cleft side of the maxilla. There was a close relationship between the defect parameters and those of the cleft side of the maxilla.

CONCLUSIONS

Based on the 3D volumetric segmentations, significant hypoplasia of the maxilla on the cleft side existed in the pyriform aperture and alveolar crest area near the defect. The defect structures appeared to contribute to the variability of the maxilla on the cleft side.

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.

Three-Dimensional Analysis of Craniofacial Structures of Individuals With Nonsyndromic Unilateral Complete Cleft Lip and Palate

ABSTRACT

Cleft lip and palate (CLP) is one of the most common congenital deformities. Primary surgeries at an early age result in scar formation, which may impede the growth of craniofacial structures of the maxilla. Orthodontist's role in the management of individuals with CLP is important and starts from the time of birth. The knowledge of craniofacial structures in individuals with a cleft is essential for treatment planning. The purpose of this study was to analyze and compare craniofacial structures of cleft and noncleft side of individuals with non-syndromic unilateral complete cleft lip and palate (NSUCCLP) using cone-beam computed tomography (CBCT). CBCT scans of individuals with NSUCCLP (n = 42) were retrieved from the databases of two cleft centers, which followed the same protocols for timing and type of primary surgeries and secondary alveolar bone grafting (SABG). DICOM files of CBCT scans were integrated into Dolphin 3D software, and analysis was carried out in multiplanar views. The craniofacial structures of individuals with NSUCCLP were analyzed using fourteen parameters. Measurements were also recorded between the cleft and noncleft sides for comparison. The volume of the maxilla was generated by isolating it from adjacent structures on a 3D reconstructed model. MAWC, MAWPM1, MAWPM2, MAWM1, and MV of the cleft side was less than noncleft side (P < 0.05). MHP @ N Aper is less on the noncleft side (P < 0.05). There is an asymmetry of structures around the dentoalveolar and nasal region; however, asymmetries were not affected at deeper structures of the craniofacial region of individuals with NSUCCLP.

Three-dimensional evaluation of the correlation between lip canting and craniofacial planes

Objective

This study aimed to analyze the correlation of horizontal and sagittal planes used in two-dimensional diagnosis with lip canting by using threedimensional (3D) analysis.

Methods

Fifty-two patients (25 men, 27 women; average age: 24 years) undergoing treatment for dentofacial deformity were enrolled. Computed tomography images were acquired, and digital imaging and communication in medicine files were reconstructed into a 3D virtual model wherein horizontal and sagittal craniofacial planes were measured. Subsequently, the correlations of lip canting with these horizontal and sagittal planes were investigated.

Results

The mandibular symmetry plane, the occlusal plane, Camper's plane, the mandibular plane, Broadbent's plane, and the nasal axis plane were correlated with the amount of lip canting (Pearson's correlation coefficients: 0.761, 0.648, 0.556, 0.526, 0.438, and 0.406, respectively). Planes associated with the lower part of the face showed the strongest correlations; the strength of the correlations decreased in the midfacial and cranial regions. None of the planes showed statistically significant differences between patients with clinical lip canting (> 3°) and those without prominent lip canting.

Conclusions

The findings of this study suggest that lip canting is strongly correlated with the mandibular symmetry plane, which includes menton deviation. This finding may have clinical implications with regard to the treatment of patients requiring correction of lip canting. Further studies are necessary for evaluating changes in lip canting after orthognathic surgery.

The use of Medpor implants for midface contouring in cleft patients

Three-dimensional midfacial deficiency in cleft patients is common and is frequently connected to impairment of the aesthetic facial appearance. Different approaches to augment relevant facial regions are available. Alloplastic facial implants have been established as a viable alternative to autologous tissue augmentation in various circumstances. However, in cleft patients, the application of facial implants has rarely been reported. This retrospective study aimed to evaluate the use of Medpor implants for midfacial contouring in cleft patients. Fifty-one patients with orofacial clefts were assessed with regard to defined parameters. A range of Paranasal, Malar and Nasal Dorsum Medpor implants had been used. Unilateral cleft lip and palate (UCLP) represented the most common indication, followed by bilateral cleft lip and palate (BCLP). Bilateral implant insertion was performed as a general rule with few exceptions. Insertion of implants was frequently combined with other cleft-related surgical procedures. Even after orthognathic surgery, midfacial augmentation was implemented to specifically address residual volume deficiency, particularly in the malar region. The complication rate amounted to 4.9% (6/122 implants). Based on our findings, Medpor implants are reliable and long-term stable materials to successfully augment paranasal, subnasal and malar areas as well as a solid nasal dorsum material with few complications in cleft patients.

Hard- and soft-tissue profiles of the midface region in patients with skeletal Class III malocclusion using cone-beam computed tomography multiplanar-reconstructed image analysis

Objective

This study examined cone-beam computed tomography (CBCT)-derived multiplanar-reconstructed (MPR) cross-sections to clarify the salient characteristics of patients with skeletal class III malocclusion with midface deficiency (MD).

Methods

The horizontal and sagittal plane intersection points were identified for middle-third facial analysis in 40 patients in the MD or normal (N) groups. MPR images acquired parallel to each horizontal plane were used for length and angular measurements.

Results

A comparison of the MD and N groups revealed significant differences in the zygoma prominence among female patients. The convex zygomatic area in the N group was larger than that in the MD group, and the inferior part of the midface in the N group was smaller than that in the MD group for both male and female patients. A significant difference was observed in the concave middle maxillary area among male patients.

Conclusions

This study was conducted to demonstrate the difference between MD and normal face through MPR images derived from CBCT. Male patients in the MD group had a more flattened face than did those in the N group. Female patients in the MD group showed a concave-shaped lower section of the zygoma, which tended to have more severe MD. These findings indicate that orthognathic surgery to improve skeletal discrepancy requires different approaches in male and female patients.

Cleft Skeletal Asymmetry: Asymmetry Index, Classification and Application

OBJECTIVE

To quantitatively measure the extent of 3D asymmetry of the facial skeleton in patients with unilateral cleft lip and palate (UCLP) using an asymmetry index (AI) approach, and to illustrate the applicability of the index in guiding and measuring treatment outcome.

METHOD

Two groups of subjects between the ages of 15 and 20 who had archived CBCT scan were included in this study. Twenty-five patients with complete UCLP were compared with 50 age-matched noncleft subjects. The CBCT scans were segmented and landmarked for 3D anthropometric analysis. An AI was calculated as a quantitative measure of the extent of facial skeletal asymmetry.

RESULTS

For the control group, the AI ranged from 0.72 ± 0.47 at A point to 4.77 ± 1.59 at Gonion. The degree of asymmetry increased with the increasing laterality of the landmark from the midsagittal plane. In the UCLP group, the values of AI significantly increased compared to the control group at nearly all measured landmarks. The extent of the asymmetry to involve the upper, middle, and lower facial skeleton varied widely with the individual patient with UCLP.

CONCLUSION

The asymmetry index is capable of capturing the 3D facial asymmetry of subjects with UCLP and as a basis for classification of the extent of the asymmetry. We found the index to be applicable in surgical planning and in measuring the outcome in improving the symmetry in patients who have undergone orthognathic surgery.

A cone-beam computed tomography evaluation of facial asymmetry in unilateral cleft lip and palate individuals

Our study aimed to examine facial asymmetry in patients with unilateral cleft lip and palates (UCLP) using cone-beam computed tomography (CBCT) and explore the factors responsible for lower facial asymmetry in these individuals. The experimental group included 21 adolescent patients with non-syndromic UCLP while the control group comprised 14 patients without any facial cleft defects. The maxillofacial regions of the patients in the two groups were scanned using CBCT, and the Mimics 10.01 software was used to analyze the images. Multiple linear stepwise regression analysis was used to explore the factors related to the deviation of the pogonion point (Pog). Comparison of the two groups showed that the position of the lateral point of the pyriform aperture and the length of the mandibular body exhibited significant asymmetry (P < 0.05). Pog in the UCLP group deviated to the cleft side (1.24 ± 2.28 mm), and was related to B6L(R) to Sagittal plane, CdL(R) to Sagittal plane, and U6L(R) to LS plane. We concluded that significant differences between the cleft and non-cleft sides existed only around the cleft, and not in the deeper regions of the maxillary complex. Functional adaption may be the main reason responsible for chin deviation in UCLP individuals. (J Oral Sci 58, 109-115, 2016).

A novel computer system for the evaluation of nasolabial morphology, symmetry and aesthetics after cleft lip and palate treatment. Part 1: General concept and validation

PURPOSE

The need for a widely accepted method suitable for a multicentre quantitative evaluation of facial aesthetics after surgical treatment of cleft lip and palate (CLP) has been emphasized for years. The aim of this study was to validate a novel computer system 'Analyse It Doc' (A.I.D.) as a tool for objective anthropometric analysis of the nasolabial region.

MATERIALS AND METHODS

An indirect anthropometric analysis of facial photographs was conducted with the A.I.D. system and Adobe Photoshop/ImageJ software. Intra-rater and inter-rater reliability and the time required for the analysis were estimated separately for each method and compared.

RESULTS

Analysis with A.I.D. system was nearly 10-fold faster than that with the reference evaluation method. The A.I.D. system provided strong inter-rater and intra-rater correlations for linear, angular and area measurements of the nasolabial region, as well as a significantly higher accuracy and reproducibility of angular measurements in submental view. No statistically significant inter-method differences were found for other measurements.

CONCLUSIONS

The hereby presented novel computer system is suitable for simple, time-efficient and reliable multicenter photogrammetric analyses of the nasolabial region in CLP patients and healthy subjects.

Three-dimensional craniofacial morphology in unilateral cleft lip and palate

Craniofacial morphology and asymmetry were compared before, during, and after puberty within and between patients with unilateral complete cleft lip and palate (UCCLP) and a non-cleft group. In the UCCLP group, the posterior cranial base and total cranial base were significantly shorter at all skeletal periods, the maxilla was significantly retruded and posteriorly rotated, and the mandible was significantly smaller and inferoposteriorly rotated. The angle between the nasal and mandibular plane and lower anterior facial height were significantly higher, and upper posterior facial height and total posterior height were significantly lower, in the UCCLP group. Except for an increase in the nasal cavity, no significant differences were detected in facial width. For all measurements, asymmetry on the horizontal plane was more significant than that on the vertical plane. Asymmetries in the UCCLP group were mostly detected during puberty. The UCCLP group had no distinctive mandibular asymmetry, as compared with the Class I group. In UCCLP patients, the cranial base, maxilla, and mandible were affected on the sagittal plane during all growth periods. However, horizontal asymmetries were mostly detected before and during puberty. Vertical asymmetries were less severe, and there was no distinctive mandibular asymmetry as compared with the Class I group. (J Oral Sci 56, 165-172, 2014).

A Multivariate Analysis of Unilateral Cleft Lip and Palate Facial Skeletal Morphology

Unilateral cleft lip and palate (UCLP) occurs when the maxillary and nasal facial prominences fail to fuse correctly during development, resulting in a palatal cleft and clefted soft and hard tissues of the dentoalveolus. The UCLP deformity may compromise an individual's ability to eat, chew, and speak. In this retrospective cross-sectional study, cone beam computed tomography (CBCT) images of 7-17-year-old individuals born with UCLP (n = 24) and age- and sex-matched controls (n = 24) were assessed. Coordinate values of three-dimensional anatomical landmarks (n = 32) were recorded from each CBCT image. Data were evaluated using principal coordinates analysis (PCOORD) and Euclidean distance matrix analysis (EDMA). Approximately 40% of morphometric variation is captured by PCOORD axes 1-3, and the negative and positive ends of each axis are associated with specific patterns of morphological differences. Approximately 36% of facial skeletal measures significantly differ by confidence interval testing (α = 0.10) between samples. Although significant form differences occur across the facial skeleton, strong patterns of morphological differences were localized to the lateral and superioinferior aspects of the nasal aperture, particularly on the clefted side of the face. The UCLP deformity strongly influences facial skeletal morphology of the midface and oronasal facial regions, and to a lesser extent the upper and lower facial skeletons. The pattern of strong morphological differences in the oronasal region combined with differences across the facial complex suggests that craniofacial bones are integrated and covary, despite influences from the congenital cleft.

Evaluation of the mandibular volume and correlating variables in patients affected by unilateral and bilateral cleft lip and palate: a cone-beam computed tomography study

OBJECTIVES

The aims of the present study were to evaluate the mandibular volume in patients affected by unilateral (UCLP) and bilateral cleft lip and palate (BCLP) and to compare the findings with a well-matched normal occlusion sample without cleft.

MATERIALS AND METHODS

The study sample consisted of 66 patients divided into UCLP (24 patients; mean age, 14.46 ± 3.24 years), BCLP (17 patients; mean age, 14.28 ± 2.85 years), and control (25 patients; mean age, 14.40 ± 2.81 years) groups. The volume of the mandible including the condyle and the roots of the teeth and craniofacial measurements were performed using cone-beam computed tomography and analyzed using the one-way variance analysis and post hoc Tukey's tests. Regression analyses were used to evaluate the relationships of the measurements and the mandibular volume.

RESULTS

Patients affected by UCLP and BCLP had similar craniofacial features (p > 0.05), including decreased SNB, Co-A, Co-Gn, Co-Go, and Go-Gn and increased ANB and SN-MP measurements compared to the control group. Both UCLP and BCLP groups had decreased values of mandibular volume compared to the normal occlusion group, while these differences were found to be statistically insignificant (p > 0.05). Co-Go (Beta = 0.420; p = 0.014) and Co-Gn variables (Beta = 0.708; p = 0.045) were positively correlated with mandibular volume, while SNB (Beta = -0.669; p = 0.044) and SN-MP (Beta = -0.358; p = 0.049) variables were negatively correlated (R (2) = 60.3 and p = 0.000).

CONCLUSION

Mandibular volume insignificantly differs in cleft patients (p > 0.05), and the variables of Co-Go, Co-Gn, SNB, and SN-MP significantly correlate with the volume.

CLINICAL RELEVANCE

This article investigates mandibular volume in patients affected by UCLP and BCLP that has never been investigated in the literature. The present study showed that both UCLP and BCLP groups had insignificantly decreased values of mandibular volume compared to the normal occlusion group.

Facial soft-tissue asymmetry in three-dimensional cone-beam computed tomography images of children with surgically corrected unilateral clefts

Cleft lip with or without cleft palate (CL/P) is a relatively common craniofacial malformation involving bony and soft-tissue disruptions of the nasolabial and dentoalveolar regions. The combination of CL/P and subsequent craniofacial surgeries to close the cleft and improve appearance of the cutaneous upper lip and nose can cause scarring and muscle pull, possibly resulting in soft-tissue depth asymmetries across the face. We tested the hypothesis that tissue depths in children with unilateral CL/P exhibit differences in symmetry across the sides of the face. Twenty-eight tissue depths were measured on cone-beam computed tomography images of children with unilateral CL/P (n = 55), aged 7 to 17 years, using Dolphin software (version 11.5). Significant differences in tissue depth symmetry were found around the cutaneous upper lip and nose in patients with unilateral CL/P.

Displacements prediction from 3D finite element model of maxillary protraction with and without rapid maxillary expansion in a patient with unilateral cleft palate and alveolus

Background

Both maxillary protraction and rapid expansion are recommended for patients with cleft palate and alveolus. The aim of the study is to establish a three-dimensional finite element model of the craniomaxillary complex with unilateral cleft palate and alveolus to simulate maxillary protraction with and without rapid maxillary expansion. The study also investigates the deformation of the craniomaxillary complex after applied orthopaedic forces in different directions.

Methods

A three dimensional finite element model of 1,277,568 hexahedral elements (C3D8) and 1,801,945 nodes was established based upon CT scan of a patient with unilateral cleft palate and alveolus on the right side in this study. A force of 4.9 N per side was directed on the anatomic height of contour on the buccal side of the first molar. The angles between the force vector and occlusal plane were −30°, −20°, −10°, 0°, 10°, 20°, and 30°. A force of 2.45 N on each loading point was directed on the anatomic height of contour on the lingual side of the first premolar and the first molar to simulate the expansion of the palate.

Results

The craniomaxillary complex displaced forward under any of the loading conditions. The sagittal and vertical displacement of the craniomaxillary complex reached their peak at the protraction degree of −10° forward and downward to the occlusal plane. There were larger sagittal displacements when the maxilla was protracted forward with maxillary expansion. The palatal plane rotated counterclockwise under any of the loading conditions. Being protracted without expansion, the dental arch was constricted. When supplemented with maxillary expansion, the width of the dental arch increased. Transverse deformation of the dental arch on affected side was different from that on unaffected side.

Conclusions

Protraction force alone led the craniomaxillary complex moved forward and counterclockwise, accompanied with lateral constrain on the dental arch. Additional rapid maxillary expansion resulted in a more positive reaction including both larger sagittal displacement and the width of the dental arch increase.

Cone-Beam Computed Tomography Assessment of Lower Facial Asymmetry in Unilateral Cleft Lip and Palate and Non-Cleft Patients with Class III Skeletal Relationship

Introduction

To evaluate, using cone-beam computed tomography (CBCT), both the condylar-fossa relationships and the mandibular and condylar asymmetries between unilateral cleft lip and palate (UCLP) patients and non-cleft patients with class III skeletal relationship, and to investigate the factors of asymmetry contributing to chin deviation.

Methods

The UCLP and non-cleft groups consisted of 30 and 40 subjects, respectively, in mixed dentition with class III skeletal relationships. Condylar-fossa relationships and the dimensional and positional asymmetries of the condyles and mandibles were examined using CBCT. Intra-group differences were compared between two sides in both groups using a paired t-test. Furthermore, correlations between each measurement and chin deviation were assessed.

Results

It was observed that 90% of UCLP and 67.5% of non-cleft subjects had both condyles centered, and no significant asymmetry was found. The axial angle and the condylar center distances to the midsagittal plane were significantly greater on the cleft side than on the non-cleft side (P=0.001 and P=0.028, respectively) and were positively correlated with chin deviation in the UCLP group. Except for a larger gonial angle on the cleft side, the two groups presented with consistent asymmetries showing shorter mandibular bodies and total mandibular lengths on the cleft (deviated) side. The average chin deviation was 1.63 mm to the cleft side, and the average absolute chin deviation was significantly greater in the UCLP group than in the non-cleft group (P=0.037).

Conclusion

Compared with non-cleft subjects with similar class III skeletal relationships, the subjects with UCLP showed more severe lower facial asymmetry. The subjects with UCLP presented with more asymmetrical positions and rotations of the condyles on axial slices, which were positively correlated with chin deviation.

Nasal airway and septal variation in unilateral and bilateral cleft lip and palate

Cleft lip and palate (CLP) affects the dentoalveolar and nasolabial facial regions. Internal and external nasal dysmorphology may persist in individuals born with CLP despite surgical interventions. 7-18 year old individuals born with unilateral and bilateral CLP (n = 50) were retrospectively assessed using cone beam computed tomography. Anterior, middle, and posterior nasal airway volumes were measured on each facial side. Septal deviation was measured at the anterior and posterior nasal spine, and the midpoint between these two locations. Data were evaluated using principal components analysis (PCA), multivariate analysis of variance (MANOVA), and post-hoc ANOVA tests. PCA results show partial separation in high dimensional space along PC1 (48.5% variance) based on age groups and partial separation along PC2 (29.8% variance) based on CLP type and septal deviation patterns. MANOVA results indicate that age (P = 0.007) and CLP type (P ≤ 0.001) significantly affect nasal airway volume and septal deviation. ANOVA results indicate that anterior nasal volume is significantly affected by age (P ≤ 0.001), whereas septal deviation patterns are significantly affected by CLP type (P ≤ 0.001). Age and CLP type affect nasal airway volume and septal deviation patterns. Nasal airway volumes tend to be reduced on the clefted sides of the face relative to non-clefted sides of the face. Nasal airway volumes tend to strongly increase with age, whereas septal deviation values tend to increase only slightly with age. These results suggest that functional nasal breathing may be impaired in individuals born with the unilateral and bilateral CLP deformity.