ラテラルウインドウテクニックとオステオトームテクニックを用いた二期的上顎洞底挙上術の一症例 : コーンビームCTでの評価を加えて

sinus floor elevation

北海道歯学会

北海道歯学雑誌

For maxillary sinus elevation, there are two major procedures, the Osteotome Technique and Lateral Window Technique. Each technique has its own advantages and disadvantages. The Osteotome Technique can be performed in a shorter time span, but should be done blindly, and initial implant fixation to the bone is limited. It is not possible in every case. On the other hand, the Lateral Window Technique can be applied is broad cases, but it inevitably requires a wide sinus membrane elevation with limited laceration. Particular to this case, the ability to stretch the membrane and with the small wall located at the floor of the sinus, thin membrane elevation is extremely difficult. Once the membrane is lacerated, the implantation itself is difficult. In the present case, we employed a two-stage method for the bone augmentation that should be conventionally performed in a lateral window technique alone because of the thin sinus floor height. Our method consisted of the procedure of the Lateral Window technique which aims the bone augmentation for preparing a minimum condition at which the sequential Osteotome Technique itself could be done safely with a certain height of bone, and that of a secondary osteotome technique which attempts a firm fixation of the implant body for functional occlusion. A morphological evaluation of the graft by a serial cone-beam CT revealed that the ratio of the pixel value at the interest point to that of the control point in the same FOV had decreased two months after surgery, but became higher afterwards. We think this method is superior to the conventional one in terms of lower invasiveness, smaller volume requirement of the filling bone, and higher certainty. Adverse effects are also decreased. We regard this two-stage method as one of the options when handling cases with a low sinus floor in which ordinal implant placement can’t be carried out.