COTTON-WOOL APPEARANCE Active phase showing disorganised bone architecture with numerous, large, multinucleated osteoclasts. The stroma is vascular and fibrous The late phase features thick trabeculae with a prominent mosaic pattern of prominent, hematoxyphilic, cement lines at the interfaces of episodes of resorption followed by deposition. Paget disease showing very prominent blue cement lines. The lamellae are arranged haphazardly giving an overall effect of a jigsaw puzzle.

1. PAGETS DISEASE
DR AMITHA G, BDS, MDS
ORAL AND MAXILLOFACIAL PATHOLOGY

2. C OT TO N - W O O L
A P P E A R A N C E

3. A c t i v e p h a s e s h o w i n g d i s o rga n i s e d
b o n e a rc h i t e c t u re w i t h n u m e ro u s ,
l a rg e , m u l t i n u c l e a t e d o s t e o c l a s t s .
T h e s t ro m a i s v a s c u l a r a n d f i b ro u s
T h e l a t e p h a s e fe a t u re s t h i c k
t ra b e c u l a e w i t h a p ro m i n e n t m o s a i c
p a t t e r n o f p ro m i n e n t ,
h e m a t ox y p h i l i c , c e m e n t l i n e s a t t h e
i n te r fa c e s o f e p i s o d e s o f re s o r p t i o n
fo l l o w e d b y d e p o s i t i o n .

4. B o t h o s t e o b l a s t i c a n d o s t e o c l a s t i c
a c t i v i t y s e e n i n re l a t i o n t o t h e
s a m e t ra b e c u l a e

5. O S T EO C L A S T S W I T H A L A R G E ,
E C TAT I C B LO O D V E S S E L
L AT E S TA G E O F PA G E T ’ S D I S EA S E

6. Pa g e t d i s e a s e s h o w i n g v e r y
p ro m i n e n t b l u e c e m e n t l i n e s .
T h e l a m e l l a e a re a r ra n g e d
h a p h a z a rd l y g i v i n g a n o v e ra l l
e f fe c t o f a j i g s a w p u z z l e .

7. THANK YOU