Journal of Indian Society of Pedodontics and Preventive Dentistry
Journal of Indian Society of Pedodontics and Preventive Dentistry
                                                   Official journal of the Indian Society of Pedodontics and Preventive Dentistry                           
Year : 2012  |  Volume : 30  |  Issue : 1  |  Page : 70--73

Amelogenesis imperfecta: A clinician's challenge


V Chamarthi1, BR Varma2, M Jayanthi3,  
1 Department of Pedodontics and Preventive Dentistry, Sree Balaji Dental College and Hospital, Chennai, Tamil Nadu, India
2 Department of Pedodontics and Preventive Dentistry, Amritha School of Dentistry, Kerala, India
3 Department of Pedodontics and Preventive Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India

Correspondence Address:
V Chamarthi
Sree Balaji Dental College and Hospital, Velachery Main Road, Pallikaranai, Chennai - 600 100, Tamil Nadu
India

Abstract

Defective enamel formation can be explained as defects occurring at the stages of enamel formation. Quantitative defects in matrix formation leads to hypoplastic form of amelogenesis imperfecta. Inadequate mineralization of matrix leads to hypocalcification and hypomaturation variants. The demarcation of matrix formation and mineralization is not so distinct. This paper describes a case of a 7-year-old boy with amelogenesis imperfecta - Type IA i.e., hypoplastic pitted autosomal dominant.



How to cite this article:
Chamarthi V, Varma B R, Jayanthi M. Amelogenesis imperfecta: A clinician's challenge.J Indian Soc Pedod Prev Dent 2012;30:70-73


How to cite this URL:
Chamarthi V, Varma B R, Jayanthi M. Amelogenesis imperfecta: A clinician's challenge. J Indian Soc Pedod Prev Dent [serial online] 2012 [cited 2020 Oct 28 ];30:70-73
Available from: https://www.jisppd.com/text.asp?2012/30/1/70/95587


Full Text

 Introduction



Amelogenesis imperfecta, a group of hereditary diseases affecting the tooth enamel in either quality or quantity, is associated with crown malformation and abnormal enamel density. [1],[2],[3]

Amelogenesis occurs in the following stages. Formative stage comprises of morphogenesis and differentiation of ameloblasts and secretion of organic matrix having a protein content of 20%. The synthesis of full thickness of enamel is accomplished at this stage. Calcification stage starts when inorganic salts are deposited in the developing organic matrix. Inorganic component of enamel is increased at the expense of organic components and water. Maturation refers to the progression of enamel mineralization.

Hypoplastic variants represent 60-73% of all cases. Hypoplastic variants show thin enamel but radiodensity appears normal. Lack of contact points appears to be present in this type. Enamel may be rough, smooth or pitted. Female carriers of x-linked forms manifest vertical banding of normal and abnormal enamel. Unerupted teeth may undergo replacement resorption. It may be associated with anterior open bite.

Hypocalicific variants represent 7% of all cases. Radiographically enamel is less opaque than dentin. The enamel thickness is initially normal but enamel is soft and easily removed soon after tooth eruption. Teeth may be light yellow to brown in color.

Hypomaturation variants represent 20-40% of all cases. Radio opacity of enamel is similar to that of dentin. Enamel tends to chip away from dentin. Enamel is mottled brown or yellow with localized or diffuse opacities.

In hypoplastic - hypomaturation with taurodontism, the enamel is thin, mottled yellow to brown and pitted. Molar teeth exhibit taurodontism and other teeth have enlarged pulp chambers.

 Case Report



A 7-year-old boy reported to the Department of Pediatric Dentistry, Ragas Dental College and Hospital, Chennai with the chief complaint of discolored teeth since the time the teeth erupted. His medical history was not significant and did not include systemic features of any of the amelogenesis imperfect-related syndromes. Patient's family revealed that the mother had a similar problem with anterior open bite. Patient has a 4-year-old sister. Both sister and father have normal teeth. [Figure 1]{Figure 1}

Patient was born full term via forceps delivery in Chennai. Family has been staying in Chennai since then. Patient is mesocephalic with straight profile. He has a class I molar relationship. Oral hygiene was fair and diet history revealed frequent consumption of sweets.

Intraoral examination revealed mixed dentition with permanent mandibular central incisors and first permanent molars. Teeth were yellow in color. Enamel was hard and the surface was pitted. Teeth most affected were first permanent molars followed by primary molars and anteriors. [Figure 2]. Dental caries was detected on right maxillary second primary molar and both right and left mandibular second primary molars.{Figure 2}

Orthopantamogram showed a full complement of developing permanent teeth. The teeth were deficient in the quantity of enamel.

Since, primary right maxillary central incisor showed physiological mobility, it was extracted and sent for histopathological examination. Cross-section showed lack of enamel-covering incisal edge area and aprismatic enamel at the lingual aspect. [Figure 3] and [Figure 4].{Figure 3}{Figure 4}

A diagnosis of amelogenesis imperfecta - Type IA was made based on clinical appearance, family history and histopathological examination.

Based on the treatment plan, the patient was counseled regarding his diet. Full-mouth scaling was done and oral hygiene instructions were given. Dental caries was excavated on right maxillary second primary molar and right and left mandibular second primary molars and composite resin restorations were placed. Stainless steel crowns were placed on first permanent molars. [Figure 5] and [Figure 6]. Patient was reviewed at 3, 6, 9 and 12 months postoperatively.{Figure 5}{Figure 6}

At 1-year recall, permanent maxillary central incisors and mandibular lateral incisors had erupted which were also hypoplastic. [Figure 7]. Composite resin veneering was done for these teeth. [Figure 8].{Figure 7}{Figure 8}

The long-term treatment plan of this patient includes the following. Composite resin veneers to be changed to porcelain veneers or crowns at a later date, stainless steel crowns to be changed to cast crown or porcelain crown and crowns to be placed on premolars after complete eruption. Preventive regime includes regular fluoride treatment, chlorhexidine mouth rinses, sealants, fluoride-containing restorative materials, dietary monitoring and regular reviews.

Prognosis for the patient is good since the clinical condition was addressed at a young age prior to occlusal wear.

 Discussion



Inherited systemic conditions with enamel defects are amelo-onycho hypohidriotic syndromes, morquio syndrome, kohlschutter syndrome, amelogenesis imperfecta and nephrocalcinosis syndrome, tricho-dento-osseous syndrome, occulo dento osseous syndrome and epidermolysis bullosa. [4]

Principles of management for amelogenesis imperfecta pose specific challenges to a dentist. Clinical problems associated are poor esthetics, chipping and attrition of enamel, exposure of dentine causing sensitivity, poor oral hygiene, gingivitis and dental caries.

Management directed at three aspects of care is prevention, restoration and esthetics. Preventive aspects in the primary and mixed dentition include dietary advice, fluoride supplements and oral hygiene instructions. Oral hygiene instructions should be given and topical fluoride application can be done during the permanent dentition.

Restorative aspects in the primary dentition includes giving glass ionomer restorations and stainless steel crowns, in the mixed dentition stainless steel crowns, adhesive casting on first permanent molars and composite or glass ionomer cements can be given and in the permanent dentition adhesive casting on premolars can be done.

The esthetic aspects in the primary dentition includes giving minimal intervention glass ionomer cement restorations, direct and indirect composite resin veneers in the mixed dentition and porcelain veneers, full crowns, overdentures and complete dentures in the permanent dentition.

Chronological enamel hypoplasia and Rh hypoplasia were ruled out for the patient, since chronological enamel hypoplasia develops when a systemic condition such as high fever during tooth development can produce a pattern of enamel defects (horizontal areas or bands) in the dentition. The timing of tooth development estimates the area of the disturbance. [5] In Rh hypoplasia, hemosiderin is deposited in the forming enamel and enamel is green to bluish in color.

Patient's family history ruled out fluorosis and tetracycline staining where tetracycline is deposited in hydroxyapatite crystals and chelation of calcium occurs resulting in yellow discoloration.

 Conclusions



Current literature pertaining to amelogenesis imperfecta is focusing on molecular genetics. Mutations have been discovered for both x-linked and autosomal dominant forms. Amelogenin (product of Amelx and Amely genes located on the X and Y chromosomes) is the most abundant protein in developing enamel. [6] This gene is thought to be crucial for regulating the size and shape of the mineralizing enamel crystallites. No longer is clinical appearance or phenotype the definitive criterion for diagnosis. With advances in the field of molecular genetics, the specific biochemical basis of conditions is being established. Future advances will no doubt lead to very specific modes of treatment including early diagnosis and interceptive management.

References

1Witkop CJ Jr. Amelogenesis imperfecta, dentinogenesis imperfecta and dentin dysplasia revisited: Problems in classification. J Oral Pathol 1988;17:547-53.
2Collins MA, Mauriello SM, Tyndall DA, Wright JT. Dental anomalies associated with amelogenesis imperfecta: A radiographic assessment. Oral Surg Oral Med Oral Pathol Oral Radio Endod 1999;88:358-64.
3Kida M, Ariga T, Shrakawa T, Oguchi H, Sakiyama Y. Autosomal dominant hypoplastic form of amelogenesis imperfecta caused by an enamelin gene mutation at the exon-intron boundary. J Dent Res 2002;81:738-42.
4Backman B. Amelogenesis imperfecta - clinical manifestations in 51 families in a Northern Swedish Country. Scand J Dent Res 1988;96:505-16.
5Simmer JP, Hu TC. Dental enamel formation and its impact on clinical dentistry. J Dent Educ 2001;65:896-905.
6Lau EC, Mohandras TK, Shapiro CJ, Slevkin HC, Snead ML. Human and mouse amelogenin gene loci are on the sex chromosomes. Genomics 1989;4:162-8.