Dentin Dysplasia (DD) :-
• is a rare disturbance of dentin formation characterized by normal enamel but atypical dentin formation with abnormal pulpal morphology.
• It was Ballschmiede in 1920 who first reported such a condition as “rootless teeth”.
• In 1939 Rushton termed this condition as “Dentin dysplasia”.
• It is an autosomal dominant • hereditary disease.
unknown etiology that affects approximately 1 :100,000.
TYPES
• Shields and associates separated it in:
1. Type I (dentin dysplasia)
2. Type II (anomalous dysplasia of dentin)
• Witkop refereed as,
1. Radicular (Type I)
2. Coronal (Type II)
3. INTRODUCTION
DENTIN
DYSPLASIA
3
DEFINITION :
Dentin Dysplasia is a rare disturbance of dentin
formation characterized by normal enamel but
atypical dentin formation with abnormal pulpal
morphology.
It was Ballschmiede in 1920 who first reported
such a condition as “rootless teeth”.
In 1939 Rushton termed this condition as DD.
It is an autosomal dominant hereditary disease.
4. TYPES
1. TYPE I OR RADICULAR DENTIN DYSPLASIA
2. TYPE II OR CORONAL DENTIN DYSPLASIA
D
E
N
T
I
N
D
Y
S
P
L
A
S
I
A
4
5. DENTIN DYSPLASIA TYPE I (RADICULAR)
DENTIN
DYSPLASIA
5
DEFINITION :
Dentin Dysplasia Type I represents peculiar disturbance in the development of radicular
dentin.
Type I Dentin Dysplasia is more common than type II Dentin Dysplasia.
CLINICAL FEATURES :
No sex predilection
Both Dentitions are affected.
The affected teeth exhibits severe mobility and they may even exfoliate prematurely due
to minor trauma , as a result of their abnormal short root.
In some cases, there may be a slight amber translucency in teeth.
In some cases, there may be delayed eruption.
CONTD.
6. 6
DENTIN
DYSPLASIA
TYPE
I
RADIOGRAPHIC FEATURES :
The root of the teeth are characteristically malformed, short, blunt or conical.
In the deciduous teeth, the pulp chambers and the root canals are completely obliterated.
In the Permanent dentition, a very thin crescent-shaped pulpal remnant of pulp may be
present. This obliteration commonly occurs preeruptively.
Periapical radiolucencies of unknown aetiology (e.g.- cyst, abscess, granuloma, etc..) may be
found in many normal appearing tooth.
CONTD.
Fig. -Panoramic radiograph shows no root formation in most of the teeth with total obliteration of the pulp chambers and
periapical radiolucency in lower right mandibular first molar, left mandibular first and second molar
7. 7
DENTIN
DYSPLASIA
TYPE
I
HISTOLOGIC FEATURES :
The enamel and mantle dentins are normal.
The remaining coronal and radicular dentin appears as a fused nodular mass comprising of
tubular dentin, osteodentin and amorphous dentin mass.
Characteristic appearance described as “ lava flowing around boulders”.
Remnants of pulp tissue occasionally be seen between normal and the abnormal dentinal
tissues.
CONTD.
A B
8. 8
DENTIN
DYSPLASIA
TYPE
I
CONTD.
C
D
E Fig.- (A) Stereomicroscopic view of ground section of permanent right maxillary first
molar showing obliteration of pulp chamber with abnormal dentin formation (Ground
section, x20) (B) Stereomicroscopic view of haematoxylin-eosin stained permanent
right maxillary first molar showing obliteration of pulp chamber with abnormal dentin
formation (H&E stain, x20) (C) Photomicrograph of ground section showing polarized
view of permanent maxillary first molar showing classic “lava flowing around boulders”
appearance. (Polarizing microscopy, × 100) (D) Photomicrograph of decalcified section
showing osteodentin with empty lacunae devoid of osteocytes (H&E stain, x100) (E)
Photomicrograph showing decalcified section showing abnormal dentin formed around
the obstacles (H&E stain, x100)
9. 9
DENTIN
DYSPLASIA
TYPE
I
PATHOGENESIS :
Dentin dysplasia type I develops probably due to a defect in the epithelial root sheath of
Hertwig, which fragments and becomes incorporated into the dental papilla, where is induces
formation of dysplastic dentin.
TREATMENT
No specific treatment is available.
10. DENTIN DYSPLASIA TYPE II (CORONAL)
DENTIN
DYSPLASIA
10
DEFINITION :
It is an autosomal dominant disorder of dentin, which mostly affects the coronal dentine.
CLINICAL FEATURES :
No sex predilection
Both Dentitions are affected.
The deciduous teeth have yellow, brown or bluish grey opalescent appearance.
CONTD.
11. 1 1
DENTIN
DYSPLASIA
TYPE
II
RADIOGRAPHIC FEATURES :
The pulp chambers of the deciduous teeth become obliterated.
Pulpal obliteration only after tooth eruption.
The permanent teeth exhibit an abnormally large pulp chamber in the coronal portion of the
tooth described as “ thistle-tube” in shape, and within such areas radiopaque foci
resembling pulp stone may be found.
CONTD.
Fig. - Panoramic radiograph showing normal enamel, thin dentine, enlarged pulp chambers extending into
the roots of normal length. Sudden constriction at the base of pulp chamber along with very thin root canals
giving a typical “thistle tube appearance”
12. 1 2
DENTIN
DYSPLASIA
TYPE
II
HISTOLOGIC FEATURES :
The deciduous teeth exhibit amorphous and atubular dentin in the radicular portion.
The permanent teeth may have the presence of abnormal globular or interglobular dentin.
The pulp chambers exhibit presence of multiple pulp stones or denticles.
TREATMENT : NO SPECIFIC TREATMENT AVIALABLE.
Fig. - H and E staining revealed normal enamel with areas of abnormal calcification in dentine and pulp stones. Entrapped
cells were seen within lacunae suggestive of osteodentin.