咬筋にボツリヌス毒素を繰り返し注射すると、ヒト成人の骨の変化が誘発される。縦断的研究

Repeated injections of botulinum toxin into the masseter muscle induce bony changes in human adults: A longitudinal study.

• Hwa-Jin Lee
• Sung-Jin Kim
• Kee-Joon Lee
• Hyung-Seog Yu
• Hyoung-Seon Baik

抄録

目的:

咬合性肥大症患者へのボツリヌス毒素A型（BoNT-A）注射後の下顎歯角部の軟組織および硬組織の変化を3次元コーンビームコンピュータ断層撮影（3D-CBCT）を用いて評価すること。

OBJECTIVE: To evaluate soft- and hard-tissue changes in the mandibular angle area after the administration of botulinum toxin type A (BoNT-A) injection to patients with masseteric hypertrophy by using three-dimensional cone-beam computed tomography (3D-CBCT).

方法:

20名のボランティアを無作為に10名の患者を2群に分けた。I群の患者は両咬筋にBoNT-Aを1回注射し、II群の患者は各咬筋にBoNT-Aを2回注射し、1回目の注射から4ヶ月後に2回目の注射を行った。両群ともに、1回目の注射の前に3D-CBTを行い、1回目の注射の6ヶ月後に3D-CBTを行った。

METHODS: Twenty volunteers were randomly divided into two groups of 10 patients. Patients in group I received a single BoNT-A injection in both masseter muscles, while those in group II received two BoNT-A injections in each masseter muscle, with the second injection being administered 4 months after the first one. In both groups, 3D-CBCT was performed before the first injection and 6 months after the first injection.

結果:

咬筋の厚さと断面積は両群とも有意に減少したが、下顎骨角部の骨間幅はいずれの群でも有意に変化しなかったが、II群ではI群よりも有意に減少が大きかった。しかし、下顎骨角部の骨量はII群でI群よりも有意に減少していた。

RESULTS: Masseter muscle thicknesses and cross-sectional areas were significantly reduced in both groups, but the reductions were significantly more substantial in group II than in group I. The intergonial width of the mandibular angle area did not change significantly in either group. However, the bone volume of the mandibular gonial angle area was more significantly reduced in group II than in group I.

結論:

BoNT-A注射の反復投与は、下顎角部の骨量変化を誘発する可能性がある。

CONCLUSIONS: The repeated administration of BoNT-A injections may induce bone volume changes in the mandibular angle area.