INCUOLATION THE BOTULINUM TOXIN-B IN THE ZYGOMITICUS OF THE RAT, FOLLOWED BY EVALUATION IT'S EFFECT HISTOLOGICALLY ON THE ZYGOMATIC BONE.

Background: Botulinum toxin is an attenuated neurotoxin of Clostridium Botulinum gram positive bacterial, which is used in medication sialorrhea, cervical dystonia, hyperhidrosis and non-surgical cosmetic operation (aesthetic) such as facial wrinkles and reduced the bulky appearance hypertrophied of masseter muscle. This study was designed to revealed the effect of zygomiticus inoculation of botulinum toxin B in zygomatic muscle of rats on zygomatic bone.

Methods: A total of 25 male albino rats (200-260 gm) were injected facial intramuscular by a single dose of 2.5 U/ botulinum toxin B. All experimental groups (4 groups, 5 each) were kept survived to the end period and sacrificed by time period [group 1 (G1)=14; group 2 (G2)=30; group 3 (G3)=45, and group 4 (G4)=60 days] post injection, moreover, 5 animals were administered nothing and kept as a control group till 60 days elapsed. Animals were killed by intense dose of chloroform and rats facial zygomatic bone removed.

Results: Zygomatic bone of G1 showed irregular boney border, degenerated osteocytes, woven collagen bundles within collar bone, reddish bone matrix and detachment of fibrous layer of periosteum in G2 results showed disappearance of osteogenic cells, lacunae devoid osteocytes, and aggregated of necrotic elements of bone tissue. In G3 groups showed great crack, disorganization of collagen bundles atrophied osteocytes the matrix of bone had necrotic areas of osteocytes, fragments of bone also demonstrated. G4 group showed massive crack underneath degenerated periosteum of bone, tunnel like furrow, filled up with cellular debris and osteogenic debris within Howship's lacunae.

Conclusion: In this present study we summarized the effect of paralyzed facial muscle by botulinum toxin B on facial bone of rats induced, secondary osteoporosis represented as irregular bone border degeneration of osteocytes, crack appeared in bony matrix, decreases in amounts of collagen bundles and separation of periosteum.