Developmental disturbances in structure - Enamel Hypoplasia.pptx

Developmental disturbances in structure - Enamel Hypoplasia.pptx

1. DEVELOPMENTAL DISTURBANCES IN STRUCTURE OF TEETH: ENAMEL HYPOPLASIA 1 Dr. Shreya Chatterjee MDS SENIOR LECTURER ORAL PATHOLOGY DEPARTMENT OF ORAL AND MAXILLOFACIAL PATHOLOGY AND MICROBIOLOGY BDS II YEAR 28/06/2024

2. CONTENTS LEARNING OBJECTIVES INTRODUCTION& TYPES CAUSES OF ENAMEL HYPOPLASIA EACH TYPE IN DETAIL LINK TO VIDEO QUESTIONS MCQS REFERENCES 2

3. LEARNING OBJECTIVES To know all the developmental disturbances affecting structure of teeth To know different forms of enamel hypoplasia To know all the causes for enamel hypoplasia 3

4. INTRODUCTION 4

5. ETIOLOGY 5

6. In mild environmental hypoplasia - few small grooves, pits, or fissures on the enamel surface. If severe - enamel may exhibit rows of deep pits arranged horizontally across the surface of the tooth. There may be only a single row of such pits or several rows indicating a series of injuries. In very severe cases - considerable portion of enamel may be absent, suggesting a prolonged disturbance in the function of the ameloblasts 6

7. Hypoplasia results - during the formative stage of enamel development. Once the enamel has calcified, no such defect can be produced. Thus, knowing the chronologic development of the deciduous and permanent teeth, it is possible to determine from the location of the defect on the teeth the approximate time at which the injury occurred 7

8. D/T NUTRITIONAL DEFICIENCY & exanthematous diseases Rickets during the time of tooth formation is the most common known cause of enamel hypoplasia. Deficiencies of vitamins A and C have also been named as causes. Some studies have indicated that the exanthematous diseases, including measles, chickenpox, and scarlet fever, are etiologic factors, but other investigators have been unable to confirm this finding. Ameloblasts are one of the most sensitive groups of cells in the body in terms of metabolic function. The type of hypoplasia occurring from these deficiency or disease states is usually of the pitting variety described above. Since the pits tend to stain, the clinical appearance of the teeth may be very unsightly. 8

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10. D/T CONGENITAL SYPHILIS This is not of the pitting variety Involves the maxillary and mandibular permanent incisors and the first molars. The anterior teeth affected are sometimes called “Hutchinson’s teeth,” while the molars have been referred to as “mulberry molars” (Moon’s molars, Fournier’s molars). Characteristically, the upper central incisor is “screw-driver” shaped, the mesial and distal surfaces of the crown tapering and converging toward the incisal edge of the tooth rather than toward the cervical margin. In addition, the incisal edge is usually notched. The mandibular central and lateral incisors may be similarly involved, although the maxillary lateral incisor may be normal. 10

11. The cause of the tapering and notching of the maxillary incisor has been explained on the basis of the absence of the central tubercle or calcification center. The crowns of the first molars in congenital syphilis are irregular and the enamel of the occlusal surface and occlusal third of the tooth appears to be arranged in an agglomerate mass of globules rather than in well-formed cusps. The crown is narrower on the occlusal surface than at the cervical margin. 11

12. D/T HYPOCALCEMIA Tetany, induced by a decreased level of calcium in the blood, may result from several conditions, the most common being vitamin D deficiency and parathyroid deficiency). In tetany the serum calcium level may fall as low as 6–8 mg per 100 mL, and at this level enamel hypoplasia is frequently produced in teeth developing concomitantly. This type of enamel hypoplasia is usually of the pitting variety and thus does not differ from that resulting from a nutritional disturbance or exanthematous disease. 12

13. D/T BIRTH INJURIES 13

14. D/T TRAUMA/ LOCAL INFECTION A type of hypoplasia occasionally seen involving a single tooth, most commonly one of the permanent maxillary incisors or a maxillary or mandibular premolar. There may be any degree of hypoplasia, ranging from a mild, brownish discoloration of the enamel to a severe pitting and irregularity of the tooth crown. These single teeth are frequently referred to as “Turner’s teeth ,” and the condition is called “Turner hypoplasia.” 14

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16. D/T FLUORIDE – MOTTLED ENAMEL Mottled enamel (or dental fluorosis) is a type of enamel hypoplasia that was first described under that term by G.V. Black and Frederick S. McKay in 1916 . Earlier reference to the condition is known in the foreign literature; however, Black and McKay recognized that this lesion exhibited a geographic distribution and even suggested that it was a result of some substance in the water supply, although it was not until some years later that fluorine was shown to be the causative agent 16

17. ETIOLOGY 17

18. PATHOGENESIS 18

19. Clinical features. 19

20. Treatment. Mottled enamel frequently becomes stained, an unsightly brown color. For cosmetic reasons, it has become the practice to bleach the affected teeth with an agent such as hydrogen peroxide. This is frequently effective, but the procedure must be carried out periodically, since the teeth continue to stain 20

21. D/T IDIOPATHIC CAUSES 21

22. MOLAR INCISOR HYPOMINERALISATION 22

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25. LINK TO VIDEO https://www.youtube.com/watch?v=pGhdzUj5aSk&pp=ygURZW5hbWVsIGh5cG9wbGFzaWE%3D

26. Questions Describe Developmental anomalies in structure of teeth. Classify the etiology of enamel hypoplasia

27. MCQs Which teeth are most often affected in enamel hypoplasia? A. Canines B. Third molars C. Lateral incisor D. central incisor Which is not associated with enamel hypoplasia? A. fluorosis B.  syphillis C. vit deficiency D.  kwashiorkar

28. REFERENCES Sivapathasundharam B, Rajendran A. Shafer's textbook of oral pathology. Elsevier Health Sciences; 2012 Jun 30. Neville BW, Damm DD, Allen CM, Chi AC. Oral and Maxillofacial Pathology-E-Book. Elsevier Health Sciences; 2023 May 24. Regezi JA, Sciubba J, Jordan RC. Oral pathology: clinical pathologic correlations. Elsevier Health Sciences; 2016 Feb 25. 28