PEDIATRIC DENTISTRY/Copyright @1985 byThe American Academy of Pediatric DentistryVolume 7 Number 4 CAS

The Nance-Horan syndrome of dental anomalies, congenitalcataracts, microphthalmia, and anteverted pinna: case report

W. Kim Seow, BDS, MDSc, FRACDS J.P. Brown, BDSc, MS, PhD, FRACDSK. Romaniuk, BDS, MDS, DrMedDent, PhD, FRACDS

Abstract

A case of a male patient presenting with unusualdental morphology, anterior supernumerary teeth, andagenesis of premolars associated with congenital cataracts,microphthalmia and anteverted pinna is described.Although 3 similar cases are in the medical literature,this is the first case in which the dental features aredescribed in detail.

Dental anomalies associated with many congen-

ital and hereditary syndromes have been well docu-mented. Hypodontia, the agenesis of one or moreteeth, is observed in various ectodermal dysplasiasE

while hyperdontia or the presence of supernumeraryteeth is a well-described feature of cleidocranialdysostosis 2 and Gardner’s syndrome.3 Disorders oftooth form also are associated with many genetic dis-eases. Taurodontism, an anomaly in which the fur-cation of molars is displaced apically, resulting inelongation of the body and pulp chamber and inshortening of the roots, has been described in thetrichoonychondental (TOD) syndrome, the tricho-dento-osseous syndrome, the Mohr syndrome (oral-facial-digital syndrome II) as well as the Kleinfelter’ssyndrome.4 Alteration in crown morphology also isseen in Ellis-van Creveld syndromes where conicallyshaped lateral incisors and canines and barrel-shapedcentral incisors are present.

In many of these inherited conditions, the dentalfindings are so consistent as to constitute importantfeatures of the syndrome. Thus, recognition of dentalanomalies in patients with congenital medical con-ditions may play an important role in the diagnosisof the disease, especially in cases where dysmor-

phological features and metabolic changes are not welldefined.

This report describes a patient who presented withpeg-shaped central incisors, anterior supernumeraryteeth, agenesis of premolars, and taurodont molarswith unusual rhomboidal crown morphology and someprominent pulp horns. These multiple dental anom-alies were associated with congenital cataracts, mi-crophthalmia, and anteverted pinna.

Clinical Report

The patient, a Caucasian male was 8 years of agewhen first referred to the University Dental Schoolby the School Dental Service for assessment andtreatment of supernumerary teeth.

He was of normal intelligence, with height 132.4cm (90th percentile) and weight (22.6 kg (25th centile). He had almost total loss of vision which re-sulted from bilateral cataracts and attended a schoolfor the blind. In addition, he also showed micro-phthalmia, convergent strabismus of the left eye, andnystagmus. The ears appeared large and anteverted,but no obvious abnormality of pinna morphology wasnoted (Fig 1). No other general dysmorphic featureswere found.

Dental FindingsAt the time of the first dental examination, all pri-

mary teeth were present except for the mandibularincisors, the left maxillary second molar, and themaxillary right central incisor. The maxillary perma-nent first molars and mandibular incisors were fullyerupted. The maxillary primary left central incisor wascarious, nonvital and abscessed, and the root frag-

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FIG 1. Photograph of the patient's face showing front and sideviews.

FIG 3. Orthopantomograph of the patient taken at age 7 years,10 months, revealing agenesis of both maxillary and left man-dibular second premolars, anterior supernumerary teeth, andtaurodont first permanent molars.

FIG 2. Models of the pa-tient's dentition at age 8years showing the abnor-mal morphology of theteeth.

ment of the maxillary left primary second molar pres-ent. The primary second molars appeared ankylosed.

The crowns of the primary molars were abnormal,with buccal, lingual, mesial, and distal surfaces con-verging toward the occlusal. The occlusal table thusappeared narrow. In addition, an extra cusp waspresent in the center of the occlusal surface of themaxillary right deciduous molar (Fig 2).

Examination of the occlusion revealed a deep ov-erbite with the lower incisors contacting the upperpalatal gingiva and an overjet of 3 mm. There was abilateral posterior open bite of about 3 mm.

An Orthopantomograph taken at age 7 years, 10months revealed agenesis of both maxillary and leftmandibular second premolars (Fig 3). In addition, 2supernumerary teeth were present in the area of themaxillary central incisors. Further interesting find-ings included the taurodont first permanent molarswith their large pulp chambers. Also, the mesial pulp

FIG 4. Intraoral radiographs of the patient.

horns of lower second primary molars appeared toextend very close to the occlusal surfaces. Intraoralradiographs confirmed the findings in the Orthopan-tomograph (Fig 4). No proximal caries was noted frombite-wing radiographs.

The abscessed primary incisor, the root fragmentof the maxillary second deciduous molar, and the su-pernumeraries were removed with the aid of localanesthesia. Healing was uneventful. A histologicalexamination of the supernumeraries revealed no sig-nificant findings. The patient was followed up reg-ularly for preventive care.

When the permanent teeth erupted, they were notedto be distinctly abnormal in crown morphology. Thepermanent incisors were peg-shaped with markedconvergence of the proximal surfaces toward the in-cisal edges. This was more marked in the maxillary

308 DENTAL ANOMALIES/CONGENITAL CATARACTS: Seow et al.

incisors compared to the mandibular incisors. In ad-dition, the maxillary central incisors were rotated anda large diastema was present between the teeth. Thefirst permanent molars also had occlusally converg-ing sides so that the occlusal surfaces were reduced.The cusps of these teeth were rounded and reducedin height. In addition, an extra cusp was present inthe center of the occlusal surface of each of the max-illary first permanent molars. The dentition at age 12years is shown in Figures 5, 6, and 7.

At age 12 years, another orthopantomograph re-vealed another supernumerary tooth developing inthe area of the root of the right maxillary canine. Inaddition, the roots of the maxillary central incisorsappeared dilacerated. Although the second perma-nent molars still were unerupted, it was evident fromthis radiograph that their crown morphology was alsoabnormal, with tapered proximal surfaces. These teethwere also taurodont, similar to the first permanentmolars (Fig 8).

A hand-wrist radiograph revealed that the patientwas about 6 months retarded in skeletal age com-pared to the reference standards of Greulich and Pyle.6

No morphological bone defects were detected. A mildskeletal II base was observed from a lateral skullradiograph.

The mandibular second primary molars were ex-tracted to allow optimal eruption of the premolars.The dentition of the patient's mother and brother wereexamined clinically and radiographically but no sig-nificant features were noted.

Histological FindingsMicroscopically, sections of the primary molar tooth

showed a relatively thin layer of enamel with severalsites of developmental disturbances characterized bydisk-shaped depressions of the surface and accen-tuated within the body of enamel beneath these de-

fects. Highly irregular dentine with cellular cementum(or bone) was present in abundance on the floor ofthe pulp chamber, reducing its size considerably (Fig9). This tooth also exhibited bony ankylosis.

Medical HistoryThe patient was the older of 2 boys born of a non-

consanguinous marriage. He was the product of anormal, full-term, uneventful pregnancy with birthweight of 2.78 kg. Two days after birth he developedhepatosplenomegaly and jaundice with bilirubin lev-els of 6.3 mg/dl. The jaundice persisted for severalweeks and extensive investigations revealed no an-atomical abnormalities of the biliary system. How-ever, hepatosplenomegaly persisted and liver functiontests remained abnormal, with elevated SCOT, LDH,and serum alkaline phosphatase levels. Because hewas otherwise well, no further investigations wereundertaken.

At 6 months of age it was discovered that the childhad bilateral congenital cataracts with severe loss ofvision, microphthalmia, and convergent strabismusof the left eye. These findings subsequently wereconfirmed by two ophthalmologists. Because of thepresence of congenital cataracts and neonatal jaun-dice, the child was investigated for the possibility ofcongenital infection with TORCH (toxoplasmosis, otherorganisms including syphilis, rubella, cytomegalovi-rus, and herpes) organisms but laboratory tests wereinsignificant.

The child also had a history of asthma which startedat a few months of age and was controlled by sal-butamol aminophylline, and corticosteroid.

At 9 years of age, alphaj-antitrypsin deficiency wasdiagnosed by measurements of the serum levels ofthis enzyme. Alpha,-antitrypsin is an inhibitor oftrypsin and other protease enzymes in serum. Thenormal phenotype of the Pi (Protease inhibitor) sys-

Fic 5. (left) Photograph showing abnor- Fie 6. (center) Photograph of the maxil- Fie 7. (right)) Photograph of the mandi-mal permanent anterior teeth of the pa- lary teeth, depicting the unusual mor- bular permanent teeth showing theirtient. phology of the maxillary permanent first abnormal morphology.

molars.

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FIG 8. Orthopantomograph of the patient taken at 12 years ofage. Note the dilacerated roots of the maxillary central inci-sors, the taurodont molars, and the supernumerary toothpresent in the area of the root of the maxillary right canine.

FIG 9. Photomicrograph of undecalcified section of the an-kylosed second primary molar. Note highly irregular dentinewith cellular cementum (or bone) at the floor of the pulpchamber. The arrows depict (a) zone of hypomineralizationassociated with enhanced striae of Retzius, (b) fractures ofenamel during preparation of section.

tern is M; the type associated with liver disease is Z7.Phenotype analysis for the protease inhibitor wasperformed on the patient, his parents, and his youngerbrother. Both the patient and his brother were typedas homozygous (phenotype PiZ) for the codominantgene and both parents were heterozygous (pheno-type PiMZ).

Other metabolic disorders such as congenital gal-actokinase deficiency were excluded by appropriatetests and chromosomal abnormalities were excludedby karyotyping.

DiscussionIn this patient, it is most likely that the dental

anomalies were associated with congenital cataracts,

microphthalmia, and the large anteverted pinna. Aliterature search revealed reports of a few patientswith similar dental anomalies and ophthalmic fea-tures. Nance et al. first described a family with con-genital X-linked cataracts, anteverted pinna, shortmetacarpals, and dental anomalies.8 These patientsincluded anterior supernumerary teeth and abnormaldental morphology nearly identical to that seen inthis patient. However, dental radiograph findings werenot reported.

Van Dorp and Delleman9 also reported a familywith X-linked congenital cataract, microphthalmia, anda peculiar form of the ear and dental anomalies sim-ilar to those seen in the present patient.

X-chromosomal cataract with microphthalmia, so-matic anomalies, and mental retardation also havebeen described by Hoefnagel et al.10 and Goldbergand McKusick.11 These authors reported that affectedmales also show a peculiar form of the ear, and thelatter authors mentioned dental anomalies includinga diastema between maxillary central incisors.

The patient described in this report appeared to bethe first member of his family to show these clinicalfeatures. Apart from his fathers being color blind, noother family members had any ophthalmic conditionsor unusual dental features. In particular, apart frommyopia, no ophthalmic abnormalities were detectedin the mother. The possible genetic basis of congen-ital cataracts in this case is thus unknown. It may beX-linked like the other reported cases; however, thisis not definite because of the negative family history.

On the other hand, the etiology of the condition inthis child may not have been a hereditary conditionbut one caused by an environmental agent. Manyinfections such as congenital syphilis and rubella cancause congenital cataracts, neonatal jaundice, anddental anomalies. However, in this patient, such con-genital infections had been excluded by appropriatelaboratory tests in the neonatal period.

Alpha,-antitrypsin, a glycoprotein found in theserum in 24 phenotypic forms, is an inhibitor of tryp-sin and other proteolytic activities. Deficiency of thisenzyme predisposes to chronic liver and pulmonarydisease. The incidence of the Z phenotype which isassociated with liver disease, is estimated at 1:2000-1:4000 as an autosomal codominant gene.7

Dental abnormalities have not been reported inalpha]-antitrypsin deficiency before. It is unlikely thatthere is any relationship between this enzyme defi-ciency and the dental anomalies in this report. Thepatient's brother, a year younger in age, was identicalin phenotype (PiZ) but had no dental anomalies. Itis also of interest to note that the brother had littleevidence of liver disease.

In conclusion, the syndrome of dental anomalies,congenital cataracts, microphthalmia, and anteverted

310 DENTAL ANOMALIES/CONGENITAL CATARACTS: Seow et al.

pinna appear to be a distinct clinical entity. To dateonly 3 similar reports are in the literature; in thesereports, the dental features were described only briefly.

Dr. Seow is a lecturer, social and preventive dentistry; Dr. Brownis a senior lecturer, pediatric dentistry; and Dr. Romaniuk is asenior lecturer, oral biology, University of Queensland DentalSchool. Reprint requests should be sent to Dr. Seow, Departmentof Social & Preventive Dentistry, University of Queensland DentalSchool, Turbot St, Brisbane, Queensland, Australia 4000.

1. Lowry RB, Robinson GC, Miller JR: Hereditary ectodermaldysplasia. Symptoms, inheritance patterns, differential di-agnosis, management. Clin Pediatr 5:395M02, 1966.

2. Kalliala E, Taskinen PJ: Cleidocranial dysostosis. A report ofsix typical cases and one atypical case. Oral Surg 15:808-22,1962.

3. Gardner EJ, Richards RC: Multiple cutaneous and subcuta-neous lesions occurring simultaneously with hereditary po-lyposis and osteomatosis. Am J Hum Genet 5:139-47, 1953.

4. Jaspers MT, Witkop CJ: Taurodontism, an isolated trait as-

sociated with syndromes of X-chromosomal aneuploidy. AmJ Hum Genet 32:396-413, 1980.

5. Feingold M, Jankoski J, Johnson D, Darling DB, KreidbergMB, Wilson O, Cohen MM, Gellis SS: Ellis-van Crevald syn-drome. Clin Pediatr 5:431-36, 1966.

6. Greulich WW, Pyle SI: Radiographic Atlas of Skeletal Devel-opment of the Hand and Wrist. London; Oxford UniversityPress, 1966 pp 100-104.

7. Behrman RE, Vaughan VC, eds: Nelson’s Textbook of Pedi-atrics, 12th ed. Philadelphia; WB Saunders Co, 1983 p 964.

8. Nance WE, Warburg M, Bixler D, Helveston EM: CongenitalX-linked cataract, dental anomalies and brachymetacarpalia.Birth Defects 10:285-91, 1974.

9. Van Dorp DB, Delleman JW: A family with X-chromosomalrecessive congenital cataract, microphthalmia, a peculiar formof the ear and dental anomalies. J Pediatr Ophthalmol Stra-bismus 16:166-71, 1979.

10. Hoefnagel D, Keenan ME, Allen FH: Heredofamilial bilateralanophthalmia. Arch Ophthalmol 69:760-64, 1963.

11. Goldberg MF, McKusick VA: X-linked colobomatous micro-phthalmos and other congenital anomalies. A disorder re-sembling Lenz’s dymorphogenetic syndrome. Am JOphthalmol 71:1128-33, 1971.

Quotable Quote: man’s best friendIf a dog is man’s best friend, why is it there are an estimated 44,000 facial injuries yearly from dog bites?Children under age 10 seem to get the worst of it, accounting for nearly all of the 16,000 such injuries thatare characterized as severe.

How can you protect your child from attack? The answer to the question is not an easy one. In mostcases, the bite is not brought on by teasing or abuse; nor is the attacking dog a stranger to the child usually.The problem appears that biting around the head and mouth is a normal part of a dogs’ aggressive play. Inall likelihood, the dog is approaching the child in a playful spirit, without any intention of harming him.

The best solution probably would be not to keep large, aggressive dogs as pets, especially if you haveyoung children. German shepherds, malamutes, and huskies seem to be the breeds most inclined to bite;hounds, the least. Young dogs pose a greater danger than older ones; males more than females. Whateverits age, breed, or sex, a dog should never be left alone with a child, even if the child is in a crib or playpen.

Dog. Parent’s Magazine. August, 1985 p 18.

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