Case report: unusual dental morphology in a child with ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome.
Abstract: BACKGROUND: Anomalies of dental anatomy are common in the ectodermal dysplasia syndromes. These anomalies, when found in combination with dental caries, can pose a restorative challenge for the paediatric dentist. Modification of traditional techniques and approaches may help the practitioner provide a successful treatment outcome. Case REPORT: A 3 years and 11 months old girl with a diagnosis of ankyloblepharon-ectodermal dysplasia-cleft lip/palate (AEC) syndrome was referred for treatment to a specialist paediatric dental service. Her abnormal dental anatomy, hypodontia and dental caries formed a triad of challenges for the team. Under general anaesthesia, her dentition was restored using a combination of restorative approaches and techniques, including the placement of both composite resin and preformed metal crown restorations. FOLLOW-UP: At 18-month follow-up, the family had successfully implemented good home care and dietary practices, and the local dental service had instituted a preventive programe consisting of regular examination, advice and fluoride varnish placement. The restorations remained intact and no further caries was detected. At 24-month follow-up, the first permanent molars were partially erupted, and displayed unusually deep fissures. There was also a degree of ectopic eruption of the first permanent molars, and possibly of one of the maxilary permanent incisors. CONCLUSION: Dental care for children with AEC syndrome is optimised by early intervention, good home care and regular professional review. Dental care providers should be aware of the possibility of complex dental anatomy, and bear this in mind should it become necessary to formulate a restorative treatment plan.

Key words: Ectodermal dysplasia, dental care for children, anodontia, dental caries, dental caries/therapy.
Article Type: Case study
Subject: Tooth diseases (Risk factors)
Tooth diseases (Diagnosis)
Tooth diseases (Care and treatment)
Tooth diseases (Case studies)
Authors: FitzGerald, K.
Lynch, S.A.
McKiernan, E.
Pub Date: 08/01/2011
Publication: Name: European Archives of Paediatric Dentistry Publisher: European Academy of Paediatric Dentistry Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2011 European Academy of Paediatric Dentistry ISSN: 1818-6300
Issue: Date: August, 2011 Source Volume: 12 Source Issue: 4
Geographic: Geographic Scope: Ireland Geographic Code: 4EUIR Ireland
Accession Number: 277106774
Full Text: Background

Ankyloblepharon-ectodermal dysplasia-cleft lip/palate (AEC) syndrome is a rare, autosomal dominant disorder. It is characterised by ectodermal abnormalities, fused eyelids (ankyloblepharon) and facial clefting, and is also known as Hay-Wells syndrome [Fete et al., 2009]. The genetic basis has been elucidated and is caused by mutations in Tp63 [McGrath et al., 2001]. The mutations give rise to a wide variety of phenotypic presentations in affected patients.

Allelic disorders with overlapping features include EEC (ectodermal, ectrodactyly, cleft lip/palate), Rapp Hodgkin, ADULT (acro-dermato-ungual-lacrimal-tooth) and limb-mammary syndromes. In common with many of the EDs (ectodermal dysplasias), patients with AEC syndrome have significant dental abnormalities. Review of 34 cases in three separate case series showed 100% of AEC patients displaying dental abnormalities [Vanderhooft et al., 1993; Siegfried et al., 2005; Farrington and Lausten, 2009]. Individual case reports have also identified dental abnormalities [Rule and Shaw,1988; Macias et al., 2006]. For patients with AEC, the dental features so far described are typical of those seen in patients with ED, i.e. hypodontia, conical teeth and enamel hypoplasia. Psychosocial functioning and quality of life in children and families affected by AEC syndrome can be impacted by dental concerns [Lane et al., 2009].

Case Report

Medical history A female child of 3 years and 11 months was referred to a hospital-based paediatric dental service by her consultant plastic surgeon. She had been born with fused eyelids (ankyloblepharon), a cleft lip and palate, and anorectal atresia. A clinical diagnosis of AEC syndrome was made by a consultant clinical geneticist. Subsequent molecular analysis (both sequencing and dosage analysis) of the p63 gene failed to reveal a mutation; however the presence of a mutation in an intron, promoter or enhancer could not be excluded. Although she exhibited some developmental delay, she was making great progress, especially since starting pre-school. She had undergone multiple surgeries in relation to her cleft lip and palate (aged 18 months and 3 years 9 months) and anal abnormalities, and had tolerated these well.

Dental history As her primary dentition erupted it became apparent that she had hypodontia and anomalies of dental morphology, and her mother was concerned that her pointed incisors might cause trauma to the soft tissues. For the family, the main concern was the pointed teeth in the incisor region. She had been seen once by a community-based dental team, but no specific treatment suggested. Her home care practices consisted of once daily brushing with a 500 ppm fluoride toothpaste, and she drank primarily water and fruit juice.

Extra-oral examination Extra-oral examination was consistent with her diagnosis. The child had a well-repaired bilateral cleft lip, with associated midface retrusion, and minimal scarring of her eyelids. She had somewhat sparse hair, but this did not have an aesthetic impact.

Intra-oral and radiographic examination, and treatment needs Intra-oral examination revealed the ungrafted cleft sites and cleft-associated occlusal anomalies, with an unremarkable soft tissue examination and good oral hygiene. Examination of the dentition demonstrated that the patient had only ten primary teeth, that her molars had extra cusps, that her lower incisors were conical, and that her single maxilary incisor was long and tapered, with an overall screwdriver shape (Fig. 1a - 1d). There was no associated soft tissue trauma. The molars were measured at 12-13mm mesiodistally. The child was cooperative for orthopantomographic radiography (OPG) and this revealed her limited permanent dentition, with a significantly reduced number of primary and permanent teeth (hypodontia) and abnormal morphology (Fig. 1e).

The OPG also revealed what seemed to be an unusually deep fissure pattern for the lower right first permanent molar. The morphology of the mandibular primary molars was that of a double tooth (Fig. 1c, 1d). Unfortunately, the child had developed significant dental caries in her primary molars, and this required a restorative approach in conjunction with the implementation of a rigorous preventive program. Given the extent of dental treatment required, her young age, and limited ability to cooperate in the regular dental clinic setting, a decision was made to carry out her treatment under general anaesthesia (GA). Her treatment was scheduled for the next available opportunity due to her significant hypodontia and the limited restorative options available due to the abnormal morphology of the carious teeth.

[FIGURE 1 OMITTED]

Treatment The patient was admitted as a day case for her procedure. She was anaesthetised using inhalation induction followed by endotracheal intubation with an oral RAE tube, a nasal endotracheal tube being best avoided due to the patient's repaired cleft palate. Standard pain relief and anti-emesis medications were administered intravenously, per rectum medications being avoided given her history of imperforate anus. Following pre-operative photographic record-taking (Fig. 1a-1d) and a comprehensive examination, the dentition was restored. The carious primary molars were a restorative challenge and required some modification of traditional treatment approaches. Usually, for the restoration of large carious lesions in primary molars in a child of this age who requires a GA for dental treatment, the preformed metal crown (PMC) is the restoration of choice. The PMC is durable and has the advantage of full coronal coverage [Seale, 2002]. In this case, although the caries was relatively extensive in the occlusal surfaces of teeth 75 and 85 (Fig. 1c, 1d), a direct adhesive restoration technique was preferred, as their anatomy was so anomalous that placement of a PMC would have involved much destruction of healthy tooth structure, and possible pulpal exposure.

The caries was removed and a light cured glass ionomer base placed, followed by composite resin and conventional light cured resin sealant. Tooth 65 (Fig. 1a) had a small carious cavity which was amenable to direct adhesive restoration in a similar fashion to teeth 75 and 85, but without the need for a glass ionomer base. Tooth 55 (Figure 1a) was extensively broken down and full coverage was required for successful restoration. It also had an unusual anatomy, and a mandibular second primary molar PMC (3M ESPE Unitek) was selected as the best fit after conservative reduction and caries removal. Following adaptation of the PMC by crimping and contouring to ensure the best possible fit was achieved, glass ionomer (Ketac Cem 3M ESPE) was used to cement the crown (Fig. 2). Fluoride varnish was applied to all exposed enamel surfaces.

The patient tolerated the course of treatment well and was discharged home the same day with standard post-operative instructions and oral care advice. Follow-up at her local primary dental care clinic on a three-monthly basis was arranged, to include regular placement of fluoride varnish in conjunction with dietary and oral hygiene advice. Her family have instituted good oral care practices at home, and her dietary practices were modified in line with dental health advice. At this time a referral was made to the consultant orthodontist at the national maxillofacial unit, where orthodontic care is provided for children with cleft lip and/or palate and those with craniofacial anomalies.

[FIGURE 2 OMITTED]

Follow up

18 months On review, 18 months following treatment, the restorations were found to be intact and no further dental caries was detected (Fig. 2b). Close to this time, orthodontic review also took place, and a new OPG was exposed (Fig. 2c). This radiograph demonstrated the presence of premolars 34 and 45, which were not clearly evident on the initial OPG examination. Developing ectopia of the maxillary first permanent molars, and possibly of the maxillary left incisor, was evident on this OPG.

24 months Further review, at two years post-treatment, revealed partially erupted mandibular first permanent molars with unusually deep fissures and a mild degree of diffuse enamel opacity (Fig. 4a). These fissures had been identified as unusually deep from the original OPG radiograph (Figure 1e). Glass ionomer cement fissure sealant was placed into the accessible first permanent molar fissures. Mild ectopia of the upper right and left first permanent molars was noted at the clinical examination, (Fig. 4b) but no immediate treatment was indicated, as 69% of ectopically erupted teeth can be expected to self-correct [Barberia-Leache et al., 2005]. Should intervention be required, options available are: placement of separators; distal tipping using either removable appliances with palatal finger springs and bonded occlusal 'buttons'; or fixed loops and/or power chain. The unerupted maxilary left incisor (Fig. 2c) may require exposure at a later date if it fails to erupt.

Orthodontic and paediatric dental care is in place to monitor the developing occlusion and ensure continued oral health. From a developmental perspective, the child is thriving and the absence of ongoing serious medical concerns has allowed her and her family to focus more on her lifelong dental health.

[FIGURE 3 OMITTED]

Discussion

The oral findings of AEC syndrome in 34 patients have been reported in the literature, and have been found to be generally consistent with what might be expected by combining the dental findings of patients with ectodermal dysplasia and cleft lip/palate [Farrington and Lausten, 2009]. As such, children with AEC syndrome may be at higher risk of developing dental caries, in particular of their primary teeth [Hasslof and Twetman, 2007], which can be further complicated by their hypodontia. Ideally, anticipatory guidance and regular follow-up from an appropriate dental care provider would minimise the occurrence of dental disease. Appropriate guidance might include infant oral care measures, dietary recommendations, education regarding the impact of hypodontia and clefting on the dentition, and institution of a fluoride programme tailored to the child's needs. Regular examination will allow any caries that might develop to be treated conservatively, foregoing the need for complex restorative care.

Sometimes, the general medical concerns are overriding and dental care is overlooked. Children with complex medical issues often present late to the dental setting. If a patient with advanced dental disease in the context of AEC or another ED syndrome is encountered, as was found for the case reported above, efforts should be made to carry out their treatment promptly to minimise the loss of tooth structure and optimise the restorative treatment options available to the clinician.

Double teeth have been reported in the literature, both as an isolated finding, and in association with many conditions [Acs et al., 1992; Atar et al., 1997]. Usually, a double tooth is found in the incisor/canine region, and rarely in the molar region. There is one report in the literature of a primary molar double tooth associated with ED [Atar et al.,1997], and another of a permanent molar 'gemini' tooth in a child with AEC syndrome [Macias et al., 2006], but this case is the first report of primary molar double teeth in AEC syndrome. The unusually deep fissure pattern observed in the first permanent molar teeth and the screwdriver shape of the maxillary incisor in this case are also previously unreported for AEC syndrome.

A Tp63 mutation was not identified in this child raising the possibility of genetic heterogeneity for this disorder. The child has not developed the typical dermatological manifestations of the disorder but Tp63 causes a very variable phenotype, indicated by the numerous different distinct syndromes associated with mutations in the same gene [Brunner et al., 2002]. It is possible that she has a mutation elsewhere in the gene which has been missed on the analysis. Dental anomies including hypodontia are common in Tp63 disorders. Neural crest cells are essential for the formation of much of the craniofacial region, and teeth develop from epithelial-mesenchymal interactions between oral epithelium and neural crest derived mesenchyme. As Tp63 is expressed in the branchial arches (a derivative of neural crest cells), it is not surprising that dental anomalies are common in these group of disorders.

For teeth that have anomalies of shape and size, placement of intra-coronal restorations may sometimes be favoured over placement of full coverage restorations such as PMCs, but conventional techniques can be modified to achieve success when full coverage is required. This is demonstrated by the use of a lower molar PMC on maxillary molar in the case herin. Some modification was required and achieved through crimping and contouring the PMC with appropriate instruments.

Obviously, given the significant hypodontia associated with this condition, extraction therapy is best avoided. Long-term care might include the provision of prostheses to replace absent teeth, and the placement of definitive restorations to improve aesthetics in the anterior segment. As for all patients with abnormalities of number, size and shape of the dentition, prosthodontic treatment should be patient-led and be planned in the context of the overall health and ability to tolerate such extensive dental treatment. With stabilisation of a patient's medical condition, the focus may appropriately shift to the dental and oral health.

Conclusion

Dental care for children with AEC syndrome is optimised by early intervention, good home care and regular professional review. Dental care providers should be aware of the possibility of complex dental anatomy, and bear this in mind should it become necessary to formulate a restorative treatment plan. Orthodontic input at an appropriate stage is an important part of care for the child with a developing dentition. In the long-term, prosthodontic input can be arranged if the patient desires it.

References

Acs G, Cozzi E, Pokala P. Bilateral double primary molars: case report. Pediatr Dent, 1992; 14:115-116.

Atar G, Uzamis M, Olmez S. Ectodermal dysplasia with associated double tooth. ASDC J Dent Child, 1997; 64:362-364.

Barberia-Leache E, Suarez-ClOa MC, Saavedra-Ontiveros D. Ectopic Eruption of the Maxillary First Permanent Molar: Characteristics and Occurrence in Growing Children. Angle Orthod, 2005; 75:610-615.

Brunner HG, Hamel B C J, van Bokhoven H. The p63 gene in EEC and other syndromes. J Med Genet, 2002; 39:377-381.

Farrington F, Lausten L. Oral findings in ankyloblepharon-ectodermal dysplasia-cleft lip/palate (AEC) syndrome. Am J Med Genet A, 2009; 149A:1907-1909.

Fete M, vanBokhoven H, Clements SE et al. International Research Symposium on Ankyloblepharon-Ectodermal Defects-Cleft Lip/Palate (AEC) syndrome. Am J Med Genet A, 2009; 149A:1885-1893.

Hasslof P, Twetman S. Caries prevalence in children with cleft lip and palate-a systematic review of case-control studies. Int J Paediatr Dent, 2007; 17:313-319.

Lane MM, Dalton WT 3rd, Sherman SA et al. Psychosocial functioning and quality of life in children and families affected by AEC syndrome. Am J Med Genet A, 2009; 149A:1926-1934.

Macias E, de Carlos F, Cobo J. Hay-Wells syndrome (AEC): a case report. Oral Dis, 2006; 12:506-508.

McGrath JA, Duijf PH, Doetsch Vet al. Hay-Wells syndrome is caused by heterozygous missense mutations in the SAM domain of p63. Hum Mol Genet, 2001; 10:221-229.

Rule DC, Shaw MJ. The dental management of patients with ankyloblepharon (AEC) syndrome. Br Dent J, 1988; 164:215-218.

Seale NS. The use of stainless steel crowns. Pediatr Dent, 2002; 24:501-505.

Siegfried E, Bree A, Fete M et al. Skin erosions and wound healing in ankyloblepharon-ectodermal defect-cleft lip and/or palate. Arch Dermatol, 2005; 141:1591-1594.

Vanderhooft SL, Stephan MJ, Sybert VP. Severe skin erosions and scalp infections in AEC syndrome. Pediatr Dermatol, 1993; 10:334-340.

K. FitzGerald, Department of Paediatric Dentistry, and S.A. Lynch, National Centre for Medical Genetics, Our Lady's Children's Hospital, Crumlin, Dublin 12; E. McKiernan, National Maxillofacial Unit, St. James's Hospital, James's Street, Dublin 8; Ireland.

Postal address: K. FitzGerald Dept of Paediatric Dentistry, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland.

Email: kirsten.fitzgerald@olchc.ie
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