The term enamel hypoplasia was first used by Zsigmondy in 1894. It may be defined as an incomplete or defective formation of the organic enamel matrix of teeth
- Hereditary type: Amelogenesis imperfecta
Environmental enamel hypoplasia
- Caused by environmental factors
- Either dentition may be involved i.e. primary or permanent
- Three patterns are present –
- Diffuse opacities
- Demarcated opacities
Hypoplasia – Clinical features:
– few grooves, pits or fissures on the enamel surface.
– rows of deep pits arranged horizontally across the surface of tooth.
– may be single row of such pits or several rows indicating a series of injuries
Diffuse opacities: appear as variations in the translucency of the enamel.
– normal thickness; it has increased white opacity with no clear boundary with the adjacent normal enamel
Demarcated opacities: Enamel show areas of decreased translucence, increased opacity, and a sharp boundary with the adjacent enamel.
– enamel is of normal thickness, and the affected opacity may be white, cream, yellow or brown
Factors causing hypoplasia of enamel
- Nutrition deficiency- Vitamin A,C and D
- Exanthematous diseases
- Congenital syphilis
- Birth injury, prematurity, Rh hemolytic disease
- Local infection or trauma
- Ingestion of chemicals
- Idiopathic causes
- Deficiency of Vitamin A & C during the time of tooth formation
- Rickets: Vitamin D deficiency
- Exanthematous diseases: Measles, Chicken pox, Scarlet fever
Enamel hypoplasia due to Congenital syphilis
- Maxillary and mandibular permanent incisors and the first molars are invloved.
- Not of pitting variety
- Presents a characteristic, almost pathognomonic appearance
- Hutchinson’s teeth of incissors, Mulberry molars
- Hutchinson’s triad: Intestinal keratosis, Hutchinson’s incisor and 8th nerve deafness
- When anterior teeth are affected, they are called as Hutchinson’s teeth.
- Upper central incisor: “Screw driver’’ shaped, mesial and distal surfaces of crown tapering, notching and converging towards incisal edge.
- Cause: Explained on the basis of the absence of the central tubercle or calcification center.
- Mulberry Molars – Well formed cusps are not seen, instead they appear to be arranged in an agglomerate mass of globules.
- Crown is narrower on occlusal surface than at cervical margin
- Tetany: Vitamin D deficiency and Parathyroid deficiency.
- Low serum levels of calcium leading to enamel hypoplasia i.e. here serum calcium level fall as low as 6to 8mg.per 100ml.
- Schour in 1936: Neonatal line or ring in deciduous teeth and first permanent molars- a type of enamel hypoplasia.
- Evidences suggest, enamel hypoplasia in prematurely born children.
- Rh hemolytic disease.
- GIT disturbances in mother or illness may cause hypoplasia of prenatal enamel
Local infection or trauma
- Due to carious infection of deciduous tooth during formation of succeeding permanent tooth.
- Trauma to deciduous tooth.
- Most commonly one of the permanent maxillary incisors or a maxillary or mandibular molar
- Frequent pattern of enamel defect
- Seen in permanent teeth
- Caused by periapical inflammatory disease of overlying deciduous tooth
Flouride: Mottled enamel
- Ingestion of water with high fluoride content
- Due to disturbance of ameloblasts during formative stage of tooth development
- Enamel matrix is defective or deficient
- Higher levels of fluoride influence the calcification process of matrix
- Wide range of severity:
- Occasional white flecking or spotting of the enamel: Very mild
- White opaque areas: Mild changes
- Pitting and brownish staining of surface: Moderate to severe changes
- Corroded surface, tendency to fracture: Severely affected
Treatment and Prognosis
- Micro abrasion for dental fluorosis.
- Aesthetically or functionally defective teeth can be restored through a variety of cosmetically pleasing techniques such as:
- Acid etch composite resin restorations
- Labial veneers
- Full crowns
Article by Dr. Siri P.B.