下顎頭を含む下顎再建の4症例と術後機能の検討

抄録

Mandibular reconstruction with condylar head is an important and indispensable surgical procedure to attain functional and cosmetical recovery after hemimandibulectomy.
The widely used materials for reconstruction were autogenous, heterogenous and artificial bone, but restration by them contains many problems, especially with temporomandibular joint functions and were not always satisfactory, in mandibular movement of masticatory function. We applied the reconstruction metal plate with condylar head after hemimandibulectomy in 4 patients, and examinated post operative function.
The purpose of this paper is to clarify whether or not the mandibular function after mandibular reconstruction is satisfactory. We observed 4 patients who spent 2 to 9 years after mandibular reconstruction with a condylar head. Recently, their mandibular movement and masticatory functions were studied by Saffon Mandibular Movement Anaryzer, and EMG studies were carried out on the masseter and the temporal muscles. Maximum open distance and maximum biting force were measured with a scale and biting force meter.
Slight disturbances were observe when the limit of mandibular movement was exceeded. Deviation of the mandibule towards the operated side occured during full mouth opening. The obstruction of lateral movment to the operated side was slight and there was nobody who was unable to do the lateral movement at all. Decreases in EMG activity of the masticatory muscle and maximum biting force were observed at the operated side compared with the nonoperated side. Further, even at the non-operated side, there was an obvious decrease compared with normal persons described in the literatures. But, the electical discharge activities were not proportionally related with the maximum biting force. These results indicated that the mandibular reconstruction metal plate with a condylar head after hemimandibulectomy didn't give any incovenience to patient's routine life and can give approximate satisfuction in clinical evaluation in all the patients.