three-dimensional-cephalometric-landmark-annotation-demonstration-on

Three-Dimensional Cephalometric Landmark Annotation Demonstration on Human Cone Beam Computed Tomography Scans

Craniofacial cephalometric analysis is a diagnostic tool used for the assessment of the relationship of various bones and soft tissues in the head and ...

quantitative-assessment-protocol-for-facial-soft-tissue-volumetric

Quantitative Assessment Protocol for Facial Soft Tissue Volumetric Changes with Stereophotogrammetry

The assessment of the impact of dental and orthodontic treatment, as well as of orthognathic surgery on facial soft tissue, is critically important, ...

National Institute of Dental and Craniofacial Research

Roseman University of Health Sciences

The reproductive axis is controlled by a network of gonadotropin-releasing hormone (GnRH) neurons born in the primitive nose that migrate to the hypothalamus alongside axons of the olfactory system. The observation that congenital anosmia (inability to smell) is often associated with GnRH deficiency in humans led to the prevailing view that GnRH neurons depend on olfactory structures to reach the brain, but this hypothesis has not been confirmed.

Insight Into the Ontogeny of GnRH Neurons From Patients Born Without a Nose.

 Loeys-Dietz syndrome (LDS), an autosomal dominant rare connective tissue disorder, has multisystemic manifestations, characterised by vascular tortuosity, aneurysms and craniofacial manifestations. Based on the associated gene mutations along the transforming growth factor-beta (TGF-β) pathway, LDS is presently classified into six subtypes.  We present the oro-dental features of a cohort of 40 patients with LDS from five subtypes.  The most common oro-dental manifestations were the presence of a high-arched and narrow palate, and enamel defects. Other common characteristics included bifid uvula, submucous cleft palate, malocclusion, dental crowding and delayed eruption of permanent teeth. Both deciduous and permanent teeth had enamel defects in some individuals. We established a grading system to measure the severity of enamel defects, and we determined that the severity of the enamel anomalies in LDS is subtype-dependent. In specific, patients with TGF-β receptor II mutations (LDS2) presented with the most severe enamel defects, followed by patients with TGF-β receptor I mutations (LDS1). LDS2 patients had higher frequency of oro-dental deformities in general. Across all five subtypes, as well as within each subtype, enamel defects exhibited incomplete penetrance and variable expression, which is not associated with the location of the gene mutations.  This study describes, in detail, the oro-dental manifestations in a cohort of LDS, and we conclude that LDS2 has the most severely affected phenotype. This extensive characterisation, as well as some identified distinguishing features can significantly aid dental and medical care providers in the diagnosis and clinical management of patients with this rare connective tissue disorder.

Severity of oro-dental anomalies in Loeys-Dietz syndrome segregates by gene mutation.

Microtubules are formed from heterodimers of alpha- and beta-tubulin, each of which has multiple isoforms encoded by separate genes. Pathogenic missense variants in multiple different tubulin isoforms cause brain malformations. Missense mutations in TUBB3, which encodes the neuron-specific beta-tubulin isotype, can cause congenital fibrosis of the extraocular muscles type 3 (CFEOM3) and/or malformations of cortical development, with distinct genotype-phenotype correlations. Here, we report fourteen individuals from thirteen unrelated families, each of whom harbors the identical NM_006086.4 (TUBB3):c.785G>A (p.Arg262His) variant resulting in a phenotype we refer to as the TUBB3 R262H syndrome. The affected individuals present at birth with ptosis, ophthalmoplegia, exotropia, facial weakness, facial dysmorphisms, and, in most cases, distal congenital joint contractures, and subsequently develop intellectual disabilities, gait disorders with proximal joint contractures, Kallmann syndrome (hypogonadotropic hypogonadism and anosmia), and a progressive peripheral neuropathy during the first decade of life. Subsets may also have vocal cord paralysis, auditory dysfunction, cyclic vomiting, and/or tachycardia at rest. All fourteen subjects share a recognizable set of brain malformations, including hypoplasia of the corpus callosum and anterior commissure, basal ganglia malformations, absent olfactory bulbs and sulci, and subtle cerebellar malformations. While similar, individuals with the TUBB3 R262H syndrome can be distinguished from individuals with the TUBB3 E410K syndrome by the presence of congenital and acquired joint contractures, an earlier onset peripheral neuropathy, impaired gait, and basal ganglia malformations.

TUBB3 Arg262His causes a recognizable syndrome including CFEOM3, facial palsy, joint contractures, and early-onset peripheral neuropathy.

In this case report, we focus on Muenke syndrome (MS), a disease caused by the p.Pro250Arg variant in fibroblast growth factor receptor 3 (FGFR3) and characterized by uni- or bilateral coronal suture synostosis, macrocephaly without craniosynostosis, dysmorphic craniofacial features, and dental malocclusion. The clinical findings of MS are further complicated by variable expression of phenotypic traits and incomplete penetrance. As such, unraveling the mechanisms behind MS will require a comprehensive and systematic way of phenotyping patients to precisely identify the impact of the mutation variant on craniofacial development. To establish this framework, we quantitatively delineated the craniofacial phenotype of an individual with MS and compared this to his unaffected parents using three-dimensional cephalometric analysis of cone beam computed tomography scans and geometric morphometric analysis, in addition to an extensive clinical evaluation. Secondly, given the utility of human induced pluripotent stem cells (hiPSCs) as a patient-specific investigative tool, we also generated the first hiPSCs derived from a family trio, the proband and his unaffected parents as controls, with detailed characterization of all cell lines. This report provides a starting point for evaluating the mechanistic underpinning of the craniofacial development in MS with the goal of linking specific clinical manifestations to molecular insights gained from hiPSC-based disease modeling.

Quantitative Craniofacial Analysis and Generation of Human Induced Pluripotent Stem Cells for Muenke Syndrome: A Case Report.

Elevated transforming growth factor-beta (TGF-β) signalling has been implicated in the pathogenesis of Loeys-Dietz syndrome (LDS) and Shprintzen-Goldberg syndrome (SGS). In this study, we provide a qualitative and quantitative analysis of the craniofacial and functional features among the LDS subtypes and SGS.

Loeys-Dietz and Shprintzen-Goldberg syndromes: analysis of TGF-β-opathies with craniofacial manifestations using an innovative multimodality method.

Analyzing and interpreting cone-beam computed tomography (CBCT) images is a complicated and often time-consuming process. In this study, we present two different architectures of multi-channel deep learning (DL) models: "Ensemble" and "Synchronized multi-channel", to automatically identify and classify skeletal malocclusions from 3D CBCT craniofacial images. These multi-channel models combine three individual single-channel base models using a voting scheme and a two-step learning process, respectively, to simultaneously extract and learn a visual representation from three different directional views of 2D images generated from a single 3D CBCT image. We also employ a visualization method called "Class-selective Relevance Mapping" (CRM) to explain the learned behavior of our DL models by localizing and highlighting a discriminative area within an input image. Our multi-channel models achieve significantly better performance overall (accuracy exceeding 93%), compared to single-channel DL models that only take one specific directional view of 2D projected image as an input. In addition, CRM visually demonstrates that a DL model based on the sagittal-left view of 2D images outperforms those based on other directional 2D images.Clinical Relevance- the proposed method aims at assisting orthodontist to determine the best treatment path for the patient be it orthodontic or surgical treatment or a combination of both.

Malocclusion Classification on 3D Cone-Beam CT Craniofacial Images Using Multi-Channel Deep Learning Models.

Congenital facial weakness (CFW) encompasses a heterogenous set of rare disorders presenting with decreased facial movement from birth, secondary to impaired function of the facial musculature. The aim of the present study is to provide an analysis of subject-reported oral health-related quality of life (OHRQoL) in congenital facial weakness (CFW) disorders. Forty-four subjects with CFW and age- and sex- matched controls were enrolled in an Institutional Review Board (IRB)-approved study. Demographic data, medical and surgical history, comprehensive oral examination, and the Oral Health Impact Profile (OHIP-14) were obtained. Compared to unaffected controls, subjects with CFW had higher OHIP-14 scores overall (mean ± SD: 13.11 ± 8.11 vs. 4.46 ± 4.98,  < 0.0001) and within five of seven oral health domains, indicating decreased OHRQoL. Although subjects with Moebius syndrome (MBS) were noted to have higher OHIP-14 scores than those with Hereditary Congenital Facial Paresis (HCFP), there was no significant correlation in OHIP-14 score to age, sex, or specific diagnosis. An increase in OHIP-14 scores in subjects was detected in those who had undergone reanimation surgery. In conclusion, subjects with CFW had poorer OHRQoL compared to controls, and subjects with MBS had poorer OHRQoL than subjects with HCFP. This study provides better understanding of oral health care needs and quality of life in a CFW cohort and suggests that guidelines for dental treatment are required.

Oral Health-Related Quality of Life in Rare Disorders of Congenital Facial Weakness.

Jansen metaphyseal chondrodysplasia (JMC) is an ultra-rare disorder caused by germline heterozygous  variants resulting in constitutive activation of parathyroid hormone type 1 receptor. A description of ocular manifestations of the disease is lacking. Six patients with JMC underwent a detailed ophthalmic evaluation, spectral-domain optical coherence tomography (OCT), visual field testing, and craniofacial CT scans. Five of 6 patients had good visual acuity. All patients had widely spaced eyes; 5/6 had downslanted palpebral fissures. One patient had proptosis, and another had bilateral ptosis. Two patients had incomplete closure of the eyelids (lagophthalmos), one had a history of progressive right facial nerve palsy with profuse epiphora, while the second had advanced optic nerve atrophy with corresponding retinal nerve fiber layer (RNFL) thinning on OCT and significant bilateral optic canal narrowing on CT scan. Additionally, this patient also had central visual field defects and abnormal color vision. A third patient had normal visual acuity, subtle temporal pallor of the optic nerve head, normal average RNFL, but decreased temporal RNFL and retinal ganglion cell layer analysis (GCA) on OCT. GCA was decreased in 4/6 patients indicating a subclinical optic nerve atrophic process. None of the patients had glaucoma or high myopia. These data represent the first comprehensive report of ophthalmic findings in JMC. Patients with JMC have significant eye findings associated with optic canal narrowing due to extensive skull base dysplastic bone overgrowth that appear to be more prevalent and pronounced with age. Progressive optic neuropathy from optic canal narrowing may be a feature of JMC, and OCT GCA can serve as a useful biomarker for progression in the setting of optic canal narrowing. We suggest that patients with JMC should undergo regular ophthalmic examination including color vision, OCT, visual field testing, orbital, and craniofacial imaging.

Ocular findings in Jansen metaphyseal chondrodysplasia.

Jansen metaphyseal chondrodysplasia (JMC) is an ultra-rare disorder caused by constitutive activation of parathyroid hormone type 1 receptor (PTH1R). We sought to characterize the craniofacial phenotype of patients with the disease. Six patients with genetically confirmed JMC underwent comprehensive craniofacial phenotyping revealing a distinct facial appearance that prompted a cephalometric analysis demonstrating a pattern of mandibular retrognathia. Oral examination was notable for flat and shallow palate, delayed eruption pattern, and impacted maxillary teeth. Subclinical and/or mild hearing loss was noted in 4 of 5 patients studied. The most common etiology was conductive, likely due to overcrowding of epitympanum which impedes the normal vibration of ossicles to sound. Paranasal sinus obliteration was noted in 5 of 6 patients. Computed tomography (CT) scan evaluation of craniofacial bones revealed bilaterally symmetric expansile lesions with predominant involvement of neural crest cell (NCC)-derived bones. Bilateral narrowing of facial nerve canals, particularly at the labyrinthine segment, was seen in 5 of 6 patients when compared to age-matched controls; 1 patient presented with progressive facial nerve palsy. Sagittal suture craniosynostosis was present in 5 of 6 patients-one of whom had a history of cranial reconstruction for pansynostosis in infancy. All patients demonstrated a significant degree of upper airway stenosis, as well as a more anterior hyoid bone displacement. Two patients had a diagnosis of obstructive sleep apnea. 18F-NaF Positron-emission tomography (PET)-CT revealed increased uptake associated with the skull base and gnathic bones in all patients. In conclusion, this first detailed systematic evaluation of the craniofacial phenotype of patients with JMC demonstrates a distinct and pronounced phenotype that predominantly affects the NCC-derived cranial bones indicating a critical role of PTH1R signaling in their development. These affects can result in significant disease-related morbidity, include hearing loss, nerve compression, craniosynostosis, dentoskeletal malocclusion, and airway compromise; all of which require close monitoring.

Jansen metaphyseal chondrodysplasia: analysis of craniofacial manifestations.

Congenital facial weakness (CFW) disorders are a heterogeneous group of rare conditions, that present at birth, with reduced facial movement, and mask-like facies. This study utilized a multimodality approach to examine the craniofacial and intraoral phenotypes among CFW disorders: Moebius syndrome (MBS), Hereditary Congenital Facial Palsy (HCFP), β-tubulin isotype 3 syndrome (CFEOM3A-TUBB3), Carey-Fineman-Ziter syndrome (CFZS), and a group of rarer disorders (Other).Prospective cohort study. Dental clinic. Sixty individuals (sex ratio 1:1, mean age 26.2 ± 17.5 years) with a diagnosis of CFW. Deep clinical craniofacial and dental phenotyping, three-dimensional facial surface and cone-beam computed tomography scans, and cephalometric and geometric morphometric analyses.CFEOM3A-TUBB3, MBS, and CFZS groups had the highest prevalence of craniofacial anomalies; HCFP individuals were least affected. CFEOM3A-TUBB3 had a higher prevalence of short lower face (75%), poor oral hygiene (100%)/decay (75%), and Class II malocclusion (87.5%). Moebius syndrome was associated with lagophthalmos (90.9%), tongue fissures (72.4%), tight/small oral orifice (51.7%), and tongue fasciculations (50%). Carey-Fineman-Ziter syndrome had oblong facial shape (100%), downward lip commissures (100%), and abnormal hearing (60%). Moderate-severe decay/gingivitis correlated with restricted oral orifice, common among patients with facial animation/sling surgery. Morphologically, the CFW cohort had a relatively small craniofacial centroid size, anthropometric measurements, and distinct craniofacial shapes for each subtype.Congenital facial weakness can result in abnormal craniofacial development in addition to the loss of facial movement. Multimodality phenotypic characterization of CFW disorders elucidated key clinical findings and distinct craniofacial shape segregation among the different groups.

ArticleTotal : 2	Year
Publication title Cited by 2	2023
Publication title	2025

Article	Year
Insight Into the Ontogeny of GnRH Neurons From Patients Born Without a Nose. The Journal of clinical endocrinology and metabolism\| PubMed ID: 32034419	2020
Severity of oro-dental anomalies in Loeys-Dietz syndrome segregates by gene mutation. Journal of medical genetics\| PubMed ID: 32152251	2020
TUBB3 Arg262His causes a recognizable syndrome including CFEOM3, facial palsy, joint contractures, and early-onset peripheral neuropathy. Human genetics\| PubMed ID: 34652576	2021
Quantitative Craniofacial Analysis and Generation of Human Induced Pluripotent Stem Cells for Muenke Syndrome: A Case Report. Journal of developmental biology\| PubMed ID: 34698187	2021
Loeys-Dietz and Shprintzen-Goldberg syndromes: analysis of TGF-β-opathies with craniofacial manifestations using an innovative multimodality method. Journal of medical genetics\| PubMed ID: 34916229	2022
Malocclusion Classification on 3D Cone-Beam CT Craniofacial Images Using Multi-Channel Deep Learning Models. Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference\| PubMed ID: 33018225	2020
Oral Health-Related Quality of Life in Rare Disorders of Congenital Facial Weakness. International journal of environmental research and public health\| PubMed ID: 38791829	2024
Ocular findings in Jansen metaphyseal chondrodysplasia. JBMR plus\| PubMed ID: 39108358	2024
Jansen metaphyseal chondrodysplasia: analysis of craniofacial manifestations. JBMR plus\| PubMed ID: 39830149	2025
Multimodality Craniofacial Phenotyping of Congenital Facial Weakness Disorders. The Cleft palate-craniofacial journal : official publication of the American Cleft Palate-Craniofacial Association\| PubMed ID: 40611650	2025

Konstantinia Almpani

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