Is a hereditary condition in which only the dentin is defective. Normal enamel is weakly attached and lost early. Affecting both decidous and permanent detition. Affected teeth are gray to yellowish brown and have broad crowns with constriction of cervical area resulting a ‘tulip’shape Radiographically, teeth appear solid, lacking pulp champers and root canals. Enamel is easily broken leading to exposure of dentin that undergo accelerated attrition. 2 types Dentinogenesis imperfecta 1 Dentinogenesis imperfecta 2 Dentinogenesis imperfecta type 1 Also called Opalescent dentin or Capdepont teeth or Den. Imperfecta with out Osteogenesis imperfecta. Or Shields type II. Affects only the teeth, no bone fractures. Blue grey or amber brown or opalescent. On X-rays teeth as bulbous crowns, roots are narrow and pulp champers and root canals are smaller than normal or completely obliterated. Enamel split from dentin when subjected to occlusal stress. Dentinogenesis imperfecta 2 Also called Shields type III or Brandywine type Crowns of the deciduos and permanent teeth wear rapidly after eruption. Multiple pulp exposure may occur. X-rays of decidous teeth show large pulp Champers and root canals & reduced in size as age advances. Permanent teeth have pulpal spaces that are either smaller than normal or completely obliterated. Appearance of shell teeth.Autosomal Dominant Disorder: Manifested in heterozygous states At least one parent of index case is usually affected Both males and females are affected. Clinical feature can be modified by variation in penetrance and expressivity. Some individual inherit the mutant gene but are phenotpically normal. This is reffered to as “incomplete penetrance”. In many condition the age of onset is delayed. Inheritance Pattern: Typical pattern is a heterozygous affected parent with a homozygous unaffected parent. Every child has one chance in two of having the disease Both sexes are affected equally.Autosomal Recessive Disorder Largest category of Mendelian disorder Usually does not affect the parent of the affected individual, but sibling may show the disease. Complete penetrance is common. Onset is frequently early in life. Usually affect enzymatic proteins. Pattern Of Inheritance: Typical pattern is two heterozygous unaffected (carrier) parent. The triat does not usually affect the parent, but siblings may show the disease Siblings have one chance in four of being affected Both sexes affected equally. X-Linked Recessive Disorders. All sex-linked disorders are X-linked, and almost all are recessive Usually expressed only in males Rarely, due to random X-inactivation, a female will express disease, called manifesting heterozygotes.

1. DENTINOGENESIS
IMPERFECTA
DR AMITHA . G, BDS, MDS
DEPT OF ORAL AND MAXILLOFACIAL PATHOLOGY

2. Patterns Of Inheritance:
Autosomal Dominant.
Autosomal Recessive.
X-Linked Recessive.
X-Linked Dominant

3. Autosomal Dominant Disorder:
•Manifested in heterozygous states
•At least one parent of index case is usually affected
•Both males and females are affected.
•Clinical feature can be modified by variation in
penetrance and expressivity. Some individual inherit the
mutant gene but are phenotpically normal. This is
to as “incomplete penetrance”.
•In many condition the age of onset is delayed.
Inheritance Pattern:
• Typical pattern is a heterozygous affected parent with a
a homozygous unaffected parent.
•Every child has one chance in two of having the disease
• Both sexes are affected equally..

4. Autosomal Dominant Disorders
Nervous Huntington disease
Neurofibromatosis
Myotonic dystrophy
Tuerous Sclerosis
Urinary Polycystic Kidney disease
Gastrointestinal Familial polyosis coli
Hematopoietic Hereditary spherocytosis
Skeletal Marfan syndrome
Osteogenesis imperfecta
Achondroplasia
Metabolic Familial hypercholesterolmia
Acute intermittent porphyria

5. Autosomal Recessive Disorder
• Largest category of Mendelian disorder
• Usually does not affect the parent of the affected individual,
but sibling may show the disease.
• Complete penetrance is common.
• Onset is frequently early in life.
• Usually affect enzymatic proteins.
Pattern Of Inheritance:
• Typical pattern is two heterozygous unaffected (carrier)
parent.
• The triat does not usually affect the parent, but siblings may
show the disease
• Siblings have one chance in four of being affected
• Both sexes affected equally.

6. Autosomal Recessive Disorder
Metabolic Cystic fibrosis
Phenylketonuria
Galactosemia
Homocystinuria
Glycogen storage dise
Haematopoietic Sickle cell anaemia
Endocrine Congenital Adrenal hyperplasia
Skeletal Alkaptonuria
Nervous Friedrich ataxia
Spinal muscular atrophy

7. X-Linked Recessive Disorders.
•All sex-linked disorders are X-linked, and almost all are recessive
•Usually expressed only in males
•Rarely, due to random X-inactivation, a female will express
disease, called manifesting heterozygotes.

8. Pattern Of Inheritance:
•Disease usually passed on from carrier mother.
• Expressed in male offspring, females are carriers.
• Skipped generations are commonly seen.
• In this case, Recurrence risk is half of sons are affected, half of the
daughters are carriers.
Recurrence risk:
All the daughters are heterozygous carriers and all the sons are homozygous
normal.

9. X-linked Recessive Disorders
Musculoskeletal Duchene muscular dystrophy
Blood Hemophilia A and B
G6PD def.
Immune Agammaglobulinemia
Wiskott- aldrich syndrome
Metabolic Diabetes insipidus
Lesch-nyhan syndrome

10. DENTINOGENESIS IMPERFECTA
• Is a hereditary condition in which only the dentin is defective.
• Normal enamel is weakly attached and lost early.
• Affecting both decidous and permanent detition.
• Affected teeth are gray to yellowish brown and have broad crowns
with constriction of cervical area resulting a ‘tulip’shape
• Radiographically, teeth appear solid, lacking pulp champers and root
canals.
• Enamel is easily broken leading to exposure of dentin that undergo
accelerated attrition.

11. • 2 types
• Dentinogenesis imperfecta 1
• Dentinogenesis imperfecta 2
Dentinogenesis imperfecta type 1
• Also called Opalescent dentin or Capdepont teeth or Den. Imperfecta with out
imperfecta. Or Shields type II.
• Affects only the teeth, no bone fractures.
• Blue grey or amber brown or opalescent.
On X-rays teeth as bulbous crowns, roots are narrow and pulp champers and root canals
smaller than normal or completely obliterated.
• Enamel split from dentin when subjected to occlusal stress.

12. Dentinogenesis imperfecta 2
• Also called Shields type III or Brandywine type
• Crowns of the deciduos and permanent teeth wear rapidly after eruption.
• Multiple pulp exposure may occur.
• X-rays of decidous teeth show large pulp Champers and root canals & reduced
size as age advances.
• Permanent teeth have pulpal spaces that are either smaller than normal or
completely obliterated.
• Appearance of shell teeth.

13. THANK YOU
DR AMITHA . G, BDS, MDS
DEPT OF ORAL AND MAXILLOFACIAL PATHOLOGY