Pattern of Morphological Variability in Unrepaired Unilateral Clefts With and Without Cleft Palate May Suggest Intrinsic Growth Deficiency

The Asymmetry Within: A Renewed Look at Cupids Bow in Unilateral Cleft Lip

The purpose of this study is to analyze the angular variations within Cupid's bow in patients with unoperated unilateral cleft lip (UCL). Angular features of Cupid's bow were quantified in standardized presurgical photographs of children with UCL by 5 medical professionals specializing in craniofacial anomalies. The peaks and valley of Cupid's bow were identified. A cleft side (CSA) and a noncleft side angle (NCSA) were delineated and measured by each expert. The data was pooled, and the angles were analyzed for symmetry. Cupid's bow asymmetry was defined as a difference between NCSA and CSA ≥3°. Of the 37 patients studied, 29 were found to have asymmetry of Cupid's bow with an average angle difference of 8.0° (95% CI: 6.6°-9.5°). Within this group,15 patients were found with acute asymmetry and 14 with obtuse asymmetry. Geometric analysis was performed on an example of a patient with acute asymmetry to demonstrate how correction of asymmetry can be considered during surgical repair. There is an asymmetry that exists in the Cupid's bow of a significant number of patients with unoperated UCL. This finding not only adds to our understanding of UCL but may also have important implications when selecting the method/technique of surgical repair.

Three-dimensional finite element analysis on stress distribution after different palatoplasty and levator veli palatini muscle reconstruction

OBJECTIVES

To establish a three-dimensional finite element model of the upper palate, pharyngeal cavity, and levator veli palatini muscle in patients with unilateral complete cleft palate, simulate two surgical procedures that the two-flap method and Furlow reverse double Z method, observe the stress distribution of the upper palate soft tissue and changes in pharyngeal cavity area after different surgical methods, and verify the accuracy of the model by reconstructing and measuring the levator veli palatini muscle.

MATERIALS AND METHODS

Mimics, Geomagic, Ansys, and Hypermesh were applied to establish three-dimensional finite element models of the pharyngeal cavity, upper palate, and levator veli palatini muscle in patients with unilateral complete cleft palate. The parameters including length, angle, and cross-sectional area of the levator veli palatini muscle etc. were measured in Mimics, and two surgical procedures that two-flap method and Furlow reverse double Z method were simulated in Ansys, and the area of pharyngeal cavity was measured by hypermesh.

RESULTS

A three-dimensional finite element model of the upper palate, pharyngeal cavity, and bilateral levator veli palatini muscle was established in patients with unilateral complete cleft palate ; The concept of horizontal projection characteristics of the palatal dome was applied to the finite element simulation of cleft palate surgery, vividly simulating the displacement and elastic stretching of the two flap method and Furlow reverse double Z method during the surgical process; The areas with the highest stress in the two-flap method and Furlow reverse double Z method both occur in the hard soft palate junction area; In resting state, as measured, the two flap method can narrow the pharyngeal cavity area by 50.9%, while the Furlow reverse double Z method can narrow the pharyngeal cavity area by 65.4%; The measurement results of the levator veli palatini muscle showed no significant difference compared to previous studies, confirming the accuracy of the model.

CONCLUSIONS

The finite element method was used to establish a model to simulate the surgical procedure, which is effective and reliable. The area with the highest postoperative stress for both methods is the hard soft palate junction area, and the stress of the Furlow reverse double Z method is lower than that of the two-flap method. The anatomical conditions of pharyngeal cavity of Furlow reverse double Z method are better than that of two-flap method in the resting state.

CLINICAL RELEVANCE

This article uses three-dimensional finite element method to simulate the commonly used two-flap method and Furlow reverse double Z method in clinical cleft palate surgery, and analyzes the stress distribution characteristics and changes in pharyngeal cavity area of the two surgical methods, in order to provide a theoretical basis for the surgeon to choose the surgical method and reduce the occurrence of complications.

Impact of Unilateral Alveolar Bone Grafting on Nasal Volume and Nasolabial Surface: A 3D Analysis

OBJECTIVE

To determine possible effects of unilateral alveolar cleft closure on internal nasal volume and external nasolabial surface.

DESIGN

Retrospective, single-arm, cohort study.

SETTING

Institutional, tertiary care.

PATIENTS

Patients with complete unilateral cleft lip, alveolus, and palate (CUCLAP), who underwent closure of the alveolar cleft with autologous bone graft (ABG) at the age of 9-11 years, with cone beam computed tomography (CBCT) and/or three-dimensional (3D) stereophotogrammetry images taken before and one year after the ABG procedure.

INTERVENTIONS

ABG-pocedure in patients with CUCLAP.

MAIN OUTCOME MEASURES

The influence of ABG on the internal and external nasal morphology.

RESULTS

A total of 28 patients (21M/7F, 14R/14L) were divided into internal (CBCT) and external (3D-stereophotogrammetry) measurement subgroups. The external nasolabial surface showed a significant decrease of the angle alar curvature right-subnasale-alar curvature left (-1.99°; P = .02; 95% CI -2.61, -0.36) and an increase of the linear measurement between these points (+1.01 mm; P = .03; 95% CI: 0.11, 1.91). No significant differences were found when comparing the distance maps of the affected side with the non-affected side (P = .50, 95% CI: -0.20, 0.29).

CONCLUSIONS

Closure of the alveolar cleft in CUCLAP patients with ABG did not affect the internal nasal volume, but significantly affected the external nasal surface. The procedure resulted in the nose becoming wider because both alar curvatures moved caudally and laterally relative to the subnasale.

Discovery and characterization of heterogeneous and multipotent fibroblast populations isolated from excised cleft lip tissue

Background

Regularly discarded lip tissue obtained from corrective surgeries to close the cleft lip represents an easily accessible and rich source for the isolation of primary fibroblasts. Primary fibroblasts have been described to show compelling similarities to mesenchymal stem cells (MSCs). Hence, cleft lip and palate (CLP) lip-derived fibroblasts could be thought as an intriguing cell source for personalized regenerative therapies in CLP-affected patients.

Methods

Initially, we thoroughly characterized the fibroblastic nature of the lip-derived mesenchymal outgrowths by molecular and functional assays. Next, we compared their phenotype and genotype to that of bone marrow-mesenchymal stem cells (BM-MSCs) and of human lung-derived fibroblasts WI38, by assessing their morphology, surface marker expression, trilineage differentiation potential, colony-forming (CFU) capacity, and immunomodulation property. Finally, to better decipher the heterogeneity of our CLP cultures, we performed a single cell clonal analysis and tested expanded clones for surface marker expression, as well as osteogenic and CFU potential.

Results

We identified intriguingly similar phenotypic and genotypic properties between CLP lip fibroblasts and BM-MSCs, which makes them distinct from WI38. Furthermore, our own data in combination with the complex anatomy of the lip tissue indicated heterogeneity in our CLP cultures. Using a clonal analysis, we discovered single cell-derived clones with increased levels of the MSC markers CD106 and CD146 and clones with variabilities in their commitment to differentiate into bone-forming cells and in their potential to form single cell-derived colonies. However, we were not able to gain clones possessing superior MSC-like capacities when compared to the heterogeneous parental CLP population. Additionally, all clones could still generate contractile forces and retained robust levels of the fibroblast specific marker FSP1, which was not detectable in BM-MSCs.

Conclusions

Our results suggest that we isolate heterogeneous populations of fibroblasts from discarded CLP lip tissue, which show a prominently multipotent character in their entirety avoiding the need for elaborate subpopulation selections in vitro. These findings suggest that CLP lip fibroblasts might be a novel potential cell source for personalized regenerative medicine of clinical benefit for CLP patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03154-x.