Craniofacial morphology in children with van der Woude syndrome and isolated cleft palate

Craniofacial disorders and dysplasias: Molecular, clinical, and management perspectives

There is a wide spectrum of craniofacial bone disorders and dysplasias because embryological development of the craniofacial region is complex. Classification of craniofacial bone disorders and dysplasias is also complex because they exhibit complex clinical, pathological, and molecular heterogeneity. Most craniofacial disorders and dysplasias are rare but they present an array of phenotypes that functionally impact the orofacial complex. Management of craniofacial disorders is a multidisciplinary approach that involves the collaborative efforts of multiple professionals. This review provides an overview of the complexity of craniofacial disorders and dysplasias from molecular, clinical, and management perspectives.

Novel de novo missense mutation in the interferon regulatory factor 6 gene in an Italian infant with IRF6-related disorder

Background

Congenital maxillomandibular syngnathia is a rare craniofacial anomaly leading to difficulties in feeding, breathing and ability to thrive. The fusion may consist of soft tissue union (synechiae) to hard tissue union. Isolated cases of maxillomandibular fusion are extremely rare, it is most often syndromic in etiology.

Case presentation

Clinical management of a female newborn with oromaxillofacial abnormities (synechiae, cleft palate, craniofacial dysmorphisms, dental anomaly) and extraoral malformations (skinfold overlying the nails of both halluces, syndactyly, abnormal external genitalia) is presented. The associated malformations addressed to molecular genetic investigations revealing an interferon regulatory factor 6 (IRF6)-related disorder (van der Woude syndrome/popliteal pterygium syndrome). A novel de novo heterozygous mutation in exon 4 of IRF6 gene on chromosome 1q32.2, precisely c.262A > G (p.Asn88Asp), was found. Similarities are discussed with known asparagine missense mutations in the same codon, which may alter IRF6 gene function by reduced DNA-binding ability. A concomitant maternal Xp11.22 duplication involving two microRNA genes could contribute to possible epigenetic effects.

Conclusions

Our reported case carrying a novel mutation can contribute to expand understandings of molecular mechanisms underlying synechiae and orofacial clefting and to correct diagnosing of incomplete or overlapping features in IRF6-related disorders. Additional multidisciplinary evaluations to establish the phenotypical extent of the IRF6-related disorder and to address family counseling should not only be focused on the surgical corrections of syngnathia and cleft palate, but also involve comprehensive otolaryngologic, audiologic, logopedic, dental, orthopedic, urological and psychological evaluations.

Craniofacial characteristics in Van der Woude syndrome

AIM

To describe the particular craniofacial characteristics of Van der Woude syndrome(VWS) patients compared to patients with a non-syndromic cleft(CG1) and to a malocclusive healthy population(CG2).

MATERIAL AND METHODS

Retrospective case-control study. A sample of 110matched-patients was recruited(VWS(n=7),CG1(n=49),CG2(n=49)).Subsequently, 37 radiometric-variables were analysed and the dental-skeletal ages were determined. The intra/inter-observer method errors were quantified.Descriptive statistics were computed, and different inferential analysis tests were used depending on the normality of the data(Chi-square-test,Fisher-exact-test,paired-Student'sT-test,Mann-Whitney´s-test)(p-value<0.05).Pairwise comparisons were corrected by Bonferroni´s criteria.

RESULTS

VW-patients presented specific craniofacial characteristics and morphology. A marked tendency to the vertical growth pattern was found in VW-patients compared to CG1-CG2(p<0.001); at the sagittal level, skeletal class II caused by mandibular retrognathism, with a greatly increased ANB angle compared to CG1(p=0.042). Dental analysis showed that the lower incisor was more retruded and retroclined(p<0.05 in all cases)and the interincisal angulation was increased(p<0.001(CG2)).At the profile level, an open nasolabial angle(p=0.040;CG1) and a more protruding lower lip with respect to the Sn-Pg plane(p=0.040(CG1);p=0.044(CG2))were observed.

CONCLUSIONS

VW-patients present particular characteristics in the facial skeletal structures. There is a critical necessity to increase the evidence regarding specific clinical features and orofacial pathology of rare diseases such as VWS, which will help to these minorities to gain access in the future to a better quality of care with precise treatment and diagnostic necessities.

Minimal incision palatoplasty with or without muscle reconstruction in patients with isolated cleft palate-a cephalometric study at 5 and 10 years

OBJECTIVE

To compare differences in facial growth in patients with isolated clefts of the hard and/or soft palate treated with the minimal incision technique without (MI) or with muscle reconstruction (MMI).

SUBJECTS AND METHOD

A consecutive series of 170 Caucasian children born with isolated cleft palate were studied. Individuals with other craniofacial malformations, apart from Pierre Robin sequence (PRS), were excluded. The patients were treated surgically with MI (n = 85) or MMI (n = 85) palatoplasty (mean age: 13 months) and divided further into two subgroups: clefts within the soft palate only (small cleft, n = 51) and within the hard and soft palate (big cleft, n = 119). A retrospective evaluation at 5 (mean 5.4) and 10 (mean 10.3) years was performed using lateral cephalograms. Twelve skeletal and one soft tissue measurement was evaluated. Both 95% and 99% confidence intervals were calculated, two-way ANOVA and mixed model analysis was performed including/excluding PRS.

RESULTS

At 5 years, statistically significant increased inclination of the palatal plane in the big MMI cleft group (P < 0.01), increased posterior upper face height (P < 0.01), and longer mandibular length (P < 0.001) in the small MI cleft group was observed. At 10 years, statistically significant increased inclination of the palatal plane (P < 0.001), decreased posterior upper face height (P < 0.001), and longer palatal length (P < 0.01) was seen in the big MMI group.

LIMITATIONS

Retrospective single centre study, limited sample size, three surgeons.

CONCLUSION

Minor differences in craniofacial morphology were found between patients with isolated clefts treated with MI or MMI technique and between small and big cleft lengths.

Update on 13 Syndromes Affecting Craniofacial and Dental Structures

Care of individuals with syndromes affecting craniofacial and dental structures are mostly treated by an interdisciplinary team from early childhood on. In addition to medical and dental specialists that have a vivid interest in these syndromes and for whom these syndromes are of evident interest, experts of scientific background-like molecular and developmental geneticists, but also computational biologists and bioinformaticians-, become more frequently involved in the refined diagnostic and etiological processes of these patients. Early diagnosis is often crucial for the effective treatment of functional and developmental aspects. However, not all syndromes can be clinically identified early, especially in cases of absence of known family history. Moreover, the treatment of these patients is often complicated because of insufficient medical knowledge, and because of the dental and craniofacial developmental variations. The role of the team is crucial for the prevention, proper function, and craniofacial development which is often combined with orthognathic surgery. Although the existing literature does not provide considerable insight into this topic, this descriptive review aims to provide tools for the interdisciplinary team by giving an update on the genetics and general features, and the oral and craniofacial manifestations for early diagnosis. Clinical phenotyping together with genetic data and pathway information will ultimately pave the way for preventive strategies and therapeutic options in the future. This will improve the prognosis for better functional and aesthetic outcome for these patients and lead to a better quality of life, not only for the patients themselves but also for their families. The aim of this review is to promote interdisciplinary interaction and mutual understanding among all specialists involved in the diagnosis and therapeutic guidance of patients with these syndromal conditions in order to provide optimal personalized care in an integrated approach.