Unilateral Advancement of the Maxillary Minor Segment by Distraction Osteogenesis in Patients With Repaired Unilateral Cleft Lip and Palate: Report of Two Cases

The comparison of biomechanical effects of the conventional and bone-borne palatal expanders on late adolescence with unilateral cleft palate: a 3-dimensional finite element analysis

BACKGROUND

Patients with unilateral cleft lip and palate were associated with different nasomaxillary complex from the normal population. Although the biomechanical effects of conventional rapid palatal expansion (Hyrax expansion) and bone-borne rapid palatal expansion (micro-implant-assisted expansion) in non-cleft patients have been identified by multiple studies, little is known in patients with unilateral cleft lip and palate. The purpose of this study was to investigate and compare the biomechanical effects of the conventional and bone-borne palatal expanders in a late adolescence with unilateral cleft lip and palate.

METHODS

A cone beam CT scan of a late adolescence with unilateral cleft lip and palate was selected to construct the three-dimensional finite element models of teeth and craniofacial structures. The models of conventional and born-borne palatal expanders were established to simulate the clinical maxillary expansion. The geometric nonlinear theory was applied to evaluate the Von Mises stress distribution and displacements in craniofacial structures and teeth.

RESULTS

Bone-borne palatal expander achieved more transverse movement than conventional palatal expander in the whole mount of craniofacial regions, and the maximum amount of expansion was occurred anteriorly along the alveolar ridge on cleft-side. The expanding force from born-borne palatal expander resulted in more advancement in nasomaxillary complex than it in conventional palatal expander, especially in the anterior area of the minor segment of maxilla. Stresses from the both expanders distributed in similar patterns, but larger magnitudes and ranges were generated using the bone-borne expander around the maxillary buttresses and pterygoid plates of sphenoid bone. The maximum expanding stresses from born-borne palatal expander were concentrated on palatal slope supporting minscrews, whereas those from conventional palatal expander were concentrated on the anchoring molars. In addition, the buccal tipping effect of teeth generated using the bone-borne expander was less than it using the conventional palatal expander.

CONCLUSION

Bone-borne expander generated enhanced skeletal expansion at the levels of alveolar and palate in transversal direction, where the miniscrews contributed increased expanding forces to maxillary buttresses and decreased forces to buccal alveolar. Bone-borne expanders presented a superiority in correcting the asymmetric maxilla without surgical assistant in late adolescence with unilateral cleft lip and palate.

Clinical Applications of Artificial Intelligence and Machine Learning in Children with Cleft Lip and Palate-A Systematic Review

OBJECTIVE

The objective of this systematic review was (a) to explore the current clinical applications of AI/ML (Artificial intelligence and Machine learning) techniques in diagnosis and treatment prediction in children with CLP (Cleft lip and palate), (b) to create a qualitative summary of results of the studies retrieved.

MATERIALS AND METHODS

An electronic search was carried out using databases such as PubMed, Scopus, and the Web of Science Core Collection. Two reviewers searched the databases separately and concurrently. The initial search was conducted on 6 July 2021. The publishing period was unrestricted; however, the search was limited to articles involving human participants and published in English. Combinations of Medical Subject Headings (MeSH) phrases and free text terms were used as search keywords in each database. The following data was taken from the methods and results sections of the selected papers: The amount of AI training datasets utilized to train the intelligent system, as well as their conditional properties; Unilateral CLP, Bilateral CLP, Unilateral Cleft lip and alveolus, Unilateral cleft lip, Hypernasality, Dental characteristics, and sagittal jaw relationship in children with CLP are among the problems studied.

RESULTS

Based on the predefined search strings with accompanying database keywords, a total of 44 articles were found in Scopus, PubMed, and Web of Science search results. After reading the full articles, 12 papers were included for systematic analysis.

CONCLUSIONS

Artificial intelligence provides an advanced technology that can be employed in AI-enabled computerized programming software for accurate landmark detection, rapid digital cephalometric analysis, clinical decision-making, and treatment prediction. In children with corrected unilateral cleft lip and palate, ML can help detect cephalometric predictors of future need for orthognathic surgery.

Biomechanical effects of maxillary expansion on a patient with cleft palate: A finite element analysis

INTRODUCTION

The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model.

METHODS

A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP.

RESULTS

High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment.

CONCLUSIONS

The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP.

[Distraction osteogenesis in the treatment of facial and mandibular deformities]

<Zakljucak> Prikazani protokoli lecenja i kriterijumi uspesnosti svakako ce zahtevati dalje izmene i dopune, ali se mogu koristiti u buducim klinickim studijama u cilju obezbedjivanja objektivnih podataka. Buduci pravci razvoja kraniofacijalne OD ukljucuju: uticaj faktora rasta na OD, uticaj OD na kraniofacijalni skelet u procesu rasta, usavrsavanje tehnike osteotomije putem endoskopije, razvoj minijaturnih multidirekcionih distrakcionih uredjaja koji omogucavaju interceptivnu OD i modifikaciju i usavrsavanje protokola lecenja putem kraniofacijalne OD.

A meta-analysis of cleft maxillary osteotomy and distraction osteogenesis

This meta-analysis aims to provide evidence-based data to assist surgeons to make an informed choice between distraction osteogenesis or conventional osteotomy for cleft lip and palate patients. A PUBMED search of the National Library of Medicine from 1966 to December 2003 was conducted. Keywords used in the search were 'cleft', 'distraction', 'maxilla', 'maxillary', 'advancement', 'osteotomy', and 'orthognathic surgery'. This study concluded that distraction osteogenesis tends to be preferred to conventional osteotomy for younger CLP patients with more severe deformities. In such cases it was feasible to use distraction to correct moderate to large movement of the maxilla by either complete or incomplete Le Fort I osteotomy, and a concurrent mandibular osteotomy was less frequently required. Intra-operative and post-operative complications were uncommon with either technique, and some of the traditional ischemic complications related to conventional osteotomy were replaced by infection of the oral mucosa due to the prolonged retention of the distractors. There is still no conclusive data on any differences in surgical relapse, velopharyngeal function and speech between the two techniques. Both distraction osteogenesis and conventional osteotomy can deliver a marked improvement in facial aesthetics.