Assessment of regional asymmetry of the face before and after surgical correction of unilateral cleft lip

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.

Validity and reliability of three-dimensional modeling of orthodontic dental casts using smartphone-based photogrammetric technology

BACKGROUND

The development of intraoral scanning technology has effectively enhanced the digital documentation of orthodontic dental casts. Albeit, the expense of this technology is the main limitation. The purpose of the present study was to assess the validity and reliability of virtual three-dimensional (3D) models of orthodontic dental casts, which were constructed using smartphone-based 3D photogrammetry.

METHODS

A smartphone was used to capture a set of two-dimensional images for 30 orthodontic dental casts. The captured images were processed to construct 3D virtual images using Agisoft and 3DF Zephyr software programs. To evaluate the accuracy of the virtual 3D models obtained by the two software programs, the virtual 3D models were compared with cone-beam computed tomography scans of the 30 dental casts. Colored maps were used to express the absolute distances between the points of each compared two surfaces; then, the means of the 100%, 95th, and 90th of the absolute distances were calculated. A Wilcoxon signed-rank test was applied to detect any significant differences.

RESULTS

The differences between the constructed 3D images and the cone-beam computed tomography scans were not statistically significant and were accepted clinically. The deviations were mostly in the interproximal areas and in the occlusal details (sharp cusps and deep pits and fissures).

CONCLUSIONS

This study found that smartphone-based stereophotogrammetry is an accurate and reliable method for 3D modeling of orthodontic dental casts, with errors less than the accepted clinically detectable error of 0.5 mm. Smartphone photogrammetry succeeded in presenting occlusal details, but it was difficult to accurately reproduce interproximal areas.

Growth patterns of the nasolabial region following unilateral cleft lip primary repair

Surgical correction is the optimal way of repairing a congenital cleft lip. Patients with this condition often undergo initial surgical treatment at an early age and achieve an acceptable outcome. However, their levels of satisfaction will decrease in later stages of life as facial growth and development will inevitably cause changes in long-term outcomes, especially in the nasolabial region. Therefore, it is important for surgeons to understand nasolabial development after primary treatment and tailor their surgical techniques appropriately. This review focuses on the growth patterns of the nasolabial region after primary repair, so as to provide references for operative strategy.

Reconstruction of the Nose After Unilateral Cheilouranoplasty

Congenital clefts of the maxillofacial area still remain of current interest in reconstructive facial surgery. While their frequency grows up, the issues of effective surgical primary and secondary interventions are not completely solved yet. The article presents the main problems associated with the elimination of the deformations and our modifications of methods for their correction.

The study was conducted based on the Centre [2] and the University [1], Russian Federation. The project was carried out within the framework of the state assignment of the Ministry of Science and Higher Education of the Russian Federation, mnemocode 0669-2020-0008.

The research is based on the results of complex treatment of 112 patients with unilateral clefts of the upper lip and palate from the age of 5 to 34 years, 68 patients of them also carried out secondary surgeries.

The methods of performing rhinocheiloplasty by moving a "sliding" flap, of eliminating a ctenoid plica appearing after primary surgeries are presented, described, explained, and substantiated in the article.

The proposed methods gave a good or satisfactory result in 92.8% of the operated patients, which allows them to be considered effective for eliminating congenital and postoperative nasal deformities in patients with facial clefts.

: The surgical methods of eliminating congenital and postoperative deformities of the nose in patients with facial clefts should be modified in accordance with the nature of the most frequently arising shortcomings of the surgical stages of correction.

Facial Asymmetry Detected with 3D Methods in Orthodontics: A Systematic Review

Background:

Historically, the development of two-dimensional (2D) imaging techniquesforerun that of three-dimensional (3D) ones. Some 2D methods are still considered valid and effective to diagnose facial asymmetry but 3D techniques may provide more precise and accurate measurements.

Objective:

The aim of this work is to analyze the accuracy and reliability of the imaging techniques available for the diagnosis of facial asymmetry in orthodontics and find the most reliable.

Methods:

A search strategy was implemented using PubMed (National Library of Medicine, NCBI).

Results:

A total of 3201 papers were identified in electronic searches. 90 articles, available in full text, were included in the qualitative synthesis consisting of 8 reviews on the diagnosis of facial asymmetry, 22 in vivo and in vitro studies on 2D methods and 60 in vivo and in vitro studies on 3D methods to quantify the asymmetry.

Conclusion:

2D techniques include X-ray techniques such as posterior-anterior cephalogram, which still represents the first level exam in the diagnosis of facial asymmetry. 3D techniques represent the second level exam in the diagnosis of facial asymmetry. The most current used techniques are CBCT, stereophotogrammetry, laser scanning, 3D optical sensors and contact digitization. The comparison between bilateral parameters (linear distances, angles, areas, volumes and contours) and the calculation of an asymmetry index represent the best choices for clinicians who use CBCT. The creation of a color-coded distance map seems to represent the most accurate, reliable and validated methods for clinicians who use stereophotogrammetry, laser scanning and 3D optical sensors.

Short-term surgical outcomes in patients with unilateral complete cleft lip and palate after presurgical nasoalveolar molding therapy: A three-dimensional anthropometric study

OBJECTIVE

This brief research report aimed to evaluate the short-term efficacy of presurgical nasoalveolar molding (PNAM) therapy on the nasolabial morphology three dimensionally in patients with non-syndromic complete unilateral cleft lip and palate (UCLP).

METHODS

Thirty-six patients with non-syndromic complete unilateral complete cleft lip and palate were enrolled retrospectively and categorized into 2 groups: 18 patients who had received PNAM treatment (PNAM group) and 18 age-matched patients who have not receive PNAM treatment (no PNAM group) from 2017 to 2021. The average starting age for PNAM therapy was 18.33 days, and the average PNAM treatment duration was 99.08 days. Twelve nasolabial parameters were measured to compare the postsurgical outcomes of two groups.

RESULTS

In PNAM groups, cleft width, vertical distance between double Crista philtri and columellar deviation were reduced compared to that in no PNAM group. And nostril height was larger than that in no PNAM group. The differences between two groups were statistically significant (p < .05). There were no statistical differences in columellar length, nostril width and bi-alar width between two groups. However, the nostril width on cleft side in PNAM group was decreased by an average of 1.1 mm.

CONCLUSION

Our result indicated that PNAM therapy decreased cleft width and vertical distance between Crista philtri. It also increased nasal symmetry by decreasing columellar deviation, increasing nostril height.

Lips and noses in 10-year old patients with repaired complete unilateral clefts of lip, alveolus, and palate. A prospective three-centre study of the Baltic Cleft Network

This multicenter study aimed at comparing different techniques of lip and nose repair with or without NAM and primary anterior rhinoplasty in pre-adolescent children. Patients with unilateral clefts of lip, alveolus, and palate who had undergone cleft lip and nose repair were evaluated in a prospective three-centre study using standardized monochromatic, cropped photographs. Four cleft surgeons evaluated the aesthetics of the central part of the face when the patients had reached age ten years. Seventy-six sets of photographs out of 87 patients were evaluated. The overall ratings of lips and noses did not differ much between centres. However, noses of centres 1 (mean 0.74; SD 0.57) and 2 (mean 0.76; SD 0.60) had been rated better than centre 3 (mean 1.32; SD 0.78; p = 0.0078), especially "Deformation of upper part of nostril rim or poor position of alar cartilage". Centre 3 had produced better looking scars (mean 0.33; SD 0.48); p = 0.0036. Within the limitations of the study it seems that NAM and primary anterior rhinoplasty including postoperative nasal stents should be performed whenever possible in order to achieve a favorable shape of the nose and to reduce the need for secondary corrective surgery.

Aesthetic and psychosocial impact of dentofacial appearance after primary rhinoplasty for cleft lip and palate

The primary aim of this study was to demonstrate whether primary rhinoplasty shows aesthetic and psychosocial advantages for children with a complete unilateral cleft lip and palate. The second aim was to determine the satisfaction levels concerning the dentofacial appearance. Group A corresponded to patients from a center specialised in primary cheilo-rhinoplasty with 20 years' experience and Group B to patients who did not benefit from primary rhinoplasty. Children and their parents filled in a custom-designed satisfaction questionnaire on dentofacial appearance and its psychosocial impact. The variables studied were the main criterion (the nose) and secondary criteria (the upper lip, the smile, the profile and the face as a whole). 56 families consented to be involved in the study. The children did not rate statistically differently their social relationships if they had primary rhinoplasty or not. Parents however expressed very different views. They considered the nasal appearance of the children who had primary rhinoplasty as statistically more attractive and evaluated their psychosocial experience as significantly better. For the other parts of the face, in both groups, satisfaction levels of dentofacial appearance and psychosocial comfort were good (scores above 80/100). Yet, 44% of the families would go for further interventions, especially concerning the nose (13% of whom were in Group A and 42% in Group B). Within the limitations of this study, primary rhinoplasty seems to improve the patient's well-being and social life and, therefore, should be considered whenever appropriate.

Evaluation of mandibular symmetry and morphology in adult patients with unilateral posterior crossbite: a CBCT study using a surface-to-surface matching technique

OBJECTIVES

To investigate mandibular morphology in adults affected by posterior unilateral crossbite (PUXB) and to evaluate the hemi mandibular volumes from the crossbite (CB) and non-CB sides of the same patients.

METHODS

Thirty-eight cone beam computed tomography (CBCT) images were consecutively recruited and the Digital Imaging and Communications in Medicine (DICOM)-formatted scans were volume rendered into a surface three-dimensional (3D) mesh model and volumes to obtain the 3D model of the mandibular bone. To achieve the surface point-to-point analysis of the mandibular models, a reverse engineering software was used. The same procedure was performed for an age-matched control group (19 CBCT images).

RESULTS

Total mandibular volume showed a difference of 2.46 cm3 between patients and controls, which was not statistically significant. A mean difference of 1.53 cm3 was found comparing the hemi mandibular volumes from the CB and non-CB sides of PUXB patients, this difference was statistically significant (P ≤ 0.01). Findings for the surface-to-surface deviation analysis, demonstrated a higher percentage of mismatch in patients PUXB, over 10% at 0.5 mm tolerance level.

LIMITATIONS

Limitations are related to the intrinsic surfaces matching methodology, that make difficult to evaluate discrepancies among different mandibular anatomical units.

CONCLUSION

Adult patients affected by PUXB show a greater mandibular structural asymmetry compared to controls because of a lower matching percentage obtained from the surface-to-surface matching technique.

IMPLICATIONS

Treatment of adult patients affected by PUXB should take into consideration the possibility of a mild mandibular asymmetry mainly localized at the condyle and gonial angle levels.

Modeling and measuring average nasal asymmetry by dorsum midline and nose tip lateral deviation

In rhinoplasty and nasal reconstruction, achieving symmetry is critical for optimal patient outcomes and reducing re-operation rates. Assessing nasal asymmetry is challenging, both pre- and intra-operatively, if based on only a surgeons' visual perception to assess and adjust the small distances important to cosmesis (<2-3 mm). To measure nasal symmetry, we first developed an algorithm to analyze lateral nasal deviation on facial three-dimensional (3D) scans captured by external surface scanning. In this, nasal deviation is measured by first registering a 3D facial scan to orthogonal axes in order to remove tilt. The lateral position of the nasal midline is then found across transverse planes along the dorsum and nasal tip regions by probing midpoints 1 and 2 mm back from the local maximum projection. The nasal deviation measurement algorithm was validated on a simulated asymmetrical nose model with known nasal deviation. Simulated deviations were applied to the symmetrical average nose using an exponential twist away from the face, with control of the maximum deviation and degree of curvature. Modeled deviations were evaluated with the algorithm at clinically negligible (0.02-0.06 mm) average differences and for small lateral deviations (1-5 mm). Nasal deviation using the algorithms was then measured for the 100 multi-ethnic subjects in the Binghamton University 3D Facial Expression database. Average values for maximum lateral deviation, deviation across the whole nose, and deviation at the nose tip were measured to provide context to deviation measurements in surgical planning. This research presents a new nasal assessment tool that can be useful in improving symmetry in rhinoplasty and reconstruction.

An Innovative Assessment of the Dynamics of Facial Movements in Surgically Managed Unilateral Cleft Lip and Palate Using 4D Imaging

OBJECTIVE

Assess facial asymmetry during maximum smile in patients with surgically managed unilateral cleft lip and palate (UCLP), using a dynamic 3-dimensional (3D) imaging (4-dimensional) system.

DESIGN

Prospective 2 cohort comparative study.

METHODS

Twenty-five surgically managed UCLP cases and 75 controls at 8 to 10 years of age were recruited. Facial movements during maximum smile were recorded using video stereophotogrammetry at a rate of 60 3D facial images per second. Maximum smile took approximately 3 seconds and generated 180 3D facial images for the analysis. A generic facial mesh which consists of more than 7000 quasi landmarks was used for the assessment of facial asymmetry at 5 key 3D frames representing the pattern of maximum smile.

RESULTS

Statistically significant differences were seen regarding the magnitude of facial asymmetry between the UCLP group and the noncleft controls. Higher average asymmetry in the UCLP group was seen in the 3D frame midway between maximum smile and rest (frame 4) followed by the frame at peak expression of maximum smile (frame 3). The average magnitude of nasolabial asymmetry of the control group was within 0.5 mm in comparison with the UCLP cases which was about 1.8 mm.

CONCLUSION

This study provided for the first time, an objective tool for analysis of the dynamics of muscle movements which provided an unprecedented insight into the anatomical basis of the residual dysmorphology. The research demonstrates the limitations of the primary lip repair in achieving symmetrical results and underpins the required refinements to improve the quality of surgical repair of cleft lip.

Facial and midfacial symmetry in cleft patients: Comparison to non-cleft children and influence of the primary treatment concept

PURPOSE

Patients with cleft lip, alveolus and palate (CLAP) may suffer from marked asymmetry with an impact on attractiveness and psychosocial aspects. The aim of this study was to assess symmetry in CLAP patients compared to non-cleft controls of similar age with regard to cleft type and treatment concept.

MATERIALS AND METHODS

In CLAP patients with different cleft forms and in healthy non-cleft subjects (control group) a three-dimensional stereophotogrammetric face scan was performed and an objective 3D asymmetry index (AI) was calculated for the whole face, the midface, the upper lip and the nose.

RESULTS

In total, 305 patients were included: 140 CLAP patients (90 male, 50 female, mean age 9.9 ± 3.6 years) and 165 controls (87 male, 78 female, mean age 8.7 ± 2.1 years). In general, CLAP patients showed significantly higher asymmetry than controls, with the most severe asymmetry found in unilateral complete CLAP. Patients treated according to an actual concept considering reconstruction of all affected muscular systems had a significant lower and more favourable AI than patients not treated according to this concept (p < 0.05).

CONCLUSION

An adequate treatment concept is essential to achieve better results concerning symmetry in CLAP, but symmetry values of healthy non-cleft controls are not reached.