Mandibular reconstruction using a poly(L-lactide) mesh combined with autogenous particulate cancellous bone and marrow: a prospective clinical study

The purpose of this study was to evaluate the stability and viability of mandibular bone regeneration using a poly(L-lactide) (PLLA) mesh and autogenous particulate cancellous bone and marrow (PCBM). Sixty-two procedures were undertaken at eight hospitals (22 malignant tumours, 30 benign tumours, five cysts, two osteomyelitis, two trauma, and one atrophy of the alveolar ridge); the success rate was 84%. The follow-up period was between 9 and 200 months (mean 88.2 months). Consequently, bone regeneration at 6 months postoperation was excellent in 35 cases (57%), good in 17 cases (27%), and poor in 10 cases (16%). In six of the 'poor' cases, the PLLA mesh was removed due to local infection early after surgery. Bone resorption>20% was observed in only one of 46 cases with a follow-up term of >1 year. There were no signs of any other adverse effects except in one case where a section of the tray broke off late in the follow-up period. It is concluded that this method is stable and effective due to favourable morphological and functional recovery and low invasiveness. It may thus be a useful alternative procedure for mandibular reconstruction.

[A study on MRI diagnosis for primary squamous cell carcinoma in oral and maxillofacial regions]

The purpose of this study is to clarify the characteristics of MR imaging of primary squamous cell carcinoma in oral and maxillofacial regions and whether neoplastic infiltration can be delineated accurately. Seventy patients with squamous cell carcinoma underwent precontrast T1 and fast T2-weighted imaging and postcontrast T1-weighted imaging and dynamic study using the MRI system (1.5T). They were classified into 3 groups, untreated, preoperatively treated, and local recurrent group. No differences in the intensity of whole tumors, the relative intensity in the region of intensity (ROI), internal uniformity, and the time intensity curves were found among three groups. Tumor margins and staining appearances during the dynamic study showed remarkable differences. The observers of MR imaging divided the tumor size into T classifications, which agreed with clinical classification in most cases. The rate of concordance with histopathological classification were considerably high in the untreated cases (86%). In conclusion, MR imaging is a reliable technique for delineating the characteristics and infiltration of primary carcinomas with higher sensitivity when postcontrast T1-weighted imaging is applied to cases of unclear margin on precontrast T1- and T2-weighted imaging and dynamic study on the recurrent cases.

Operation for chronic dislocation of the radial head in children. Reduction by osteotomy of the ulna

Nine children with chronic post-traumatic dislocation of the head of the radius were treated by an osteotomy of the ulna with over-correction of the angular deformity and with elongation of the bone. Satisfactory results were obtained in eight cases, the only poor outcome following a three-year delay between the initial injury and the reposition. The interosseous membrane of the forearm appeared to be the most important structure in maintaining the corrected position of the radial head.