DEFINITION/OVERVIEW

Commonly referred to as enamel hypoplasia
- Enamel hypoplasia refers to inadequate deposition of enamel matrix. This can affect one or several teeth and may be focal or multifocal. The crowns of affected teeth can have areas of normal enamel next to areas of hypoplastic or missing enamel.
Apparent defect in enamel surfaces, often pitted and discolored; focal or generalized (Fig. 14-1)
Defects due to disruption of normal enamel formation
Influences during enamel formation (distemper, fever, etc.) over an extended time may cause generalized changes; during a short time (focal, local; e.g., trauma, even from deciduous tooth extraction) (Fig. 14-2) may cause specific patterns or bands
Most cases are primarily esthetic; some patients can have extensive structural damage, even root involvement
A more correct description would be enamel hypocalcification or hypomineralization since the amount of enamel is adequate (not hypoplastic), but it has defects in calcification that lead to enamel defect
- Enamel hypomineralization refers to the inadequate mineralization of enamel matrix. This often affects several or all teeth. The crowns of affected teeth are covered by soft enamel that may be worn easily.
Teeth may be more sensitive with exposed dentin, and occasionally fractures of severely compromised teeth occur; usually they remain fully functional

Figure 14-1 Enamel hypocalcification defects localized to this left maxillary canine.

Figure 14-2 Multiple enamel defects apparent on permanent mandibular incisors and canines. Deciduous teeth were extracted previously in this patient.

ETIOLOGY/PATHOPHYSIOLOGY

Dogs/cats
- Insult during enamel formation
- Canine distemper virus, fever, trauma (e.g., accidents, excessive force during deciduous tooth extraction)

SIGNALMENT/HISTORY

Dogs (more common) and cats (less common)
Often apparent at time of tooth eruption (after 6 months of age) or shortly thereafter (with signs of wear)

Irregular, pitted enamel surface with discoloration of diseased enamel and potential exposure of underlying dentin (light brown)
Early or rapid accumulation of plaque and calculus on roughened tooth surface; possible gingivitis and/or accelerated periodontal disease

Enamel staining: discolored but smooth surface (tetracycline) (see Chapter 31)
Carious lesions: cavities with decay (see Chapter 32)
Amelogenesis imperfecta: genetic and/or developmental formation and maturation abnormalities other than hypomineralization
Erosive lesions: similar to those found in cats

Complete oral examination
Appropriate preoperative diagnostics when indicated prior to procedure
Intraoral radiographs are necessary to determine viability of roots
Cases reported of abnormal root formation, no root formation, or separated crown and root (Figs. 14-3 and 14-4)

Figure 14-3 Generalized enamel hypocalcification of mandibular teeth.

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May 22, 2017 | Posted by admin in GENERAL | Comments Off