Surgical therapy represents the gold standard for the primary treatment of CHS. 4 Resection must be as wide as possible, and the presence of large healthy tissue margins (2-3 cm) seems to positively affect prognosis and chances of recurrence. 4,8 Cartilaginous or chondroid tumors are still regarded as generally radioresistant, and radiation therapy is best reserved for high-grade lesions and for surgically unresectable lesions. 1,4 Radiation therapy along with surgery seems to increase the survival rate and local control of the disease. 1,14 Local recurrences are instead independent of tumor grading and seem to be related to inadequate previous surgical therapy. 15 The metastatic rate relates to grading. 1,2 The present case, with only extended surgical resection and without radiotherapy and chemotherapy, remains no clinical and imaging signs of local recurrence and metastasis at the 6-year follow-up.The methods of mandibular condyle reconstruction include auto bone grafts, distraction osteogenesis, and standard or custom metal prosthesis. However, there are very few studies on the reconstruction of condyle with 3-dimensional printed titanium prosthesis. Here, we designed a resection guide and 3-dimensional printed titanium prosthesis for condyle reconstruction using computer-aided design and computer-aided manufacture (CAM) technology. We confirmed the accuracy of the reconstruction of condyle by determining the deviation between the preoperative design and the postoperative outcome. The results showed that the sagittal and vertical errors of condylar prosthesis implantation were within 1 mm, though the coronal outward was obvious, and a more precise guide and navigation system may be needed to make a more accurate reconstruction. The long-term esthetic and functional outcomes of the patient are good and stable without rejection, suggesting that condyle reconstruction with 3-dimensional printed titanium using computer-aided design/CAM is effective. CONCLUSIONSChondrosarcomas in temporomandibular joint are rare malignant mesenchymal tumors characterized by the formation of cartilage. Histopathological examination is essential for diagnosis, and extended surgical resection with a large clear margin represents the gold standard for the primary treatment of chondrosarcomas. Mandibular condyle defects can be satisfactorily reconstructed with 3-dimensional printed titanium using computer-aided design and CAM technology.

patients improved their headaches and impulsive behaviour. 3 Likewise, in our current case, the patient showed significantly improved gross motor, speech and language development after cranial expansion surgery. Cranial vault reconstruction should be considered to facilitate and improve the outcome of WS with craniosynostosis.Genetically, around 28 genes on the Williams-Beuren syndrome region (OMIM 194050) in chromosome 7q11.23 have been missing. 10 The most common gene contributing to WS cardiovascular pathology is known to be the elastin (ELN) gene. 4 Regarding neurocranial abnormalities, the general transcription factor II I repeat domain-containing 1 (GTF2IRD1) gene, playing a role as a transcription factor, has been implicated in the craniofacial features of WS. 10,11 The GTF2IRD1 has been reported to be linked with the suppression of RUNX2, one of the most common factors in cranial suture closure, especially in parietal bone integration. 12 For our case, the targeted gene analysis did not test in GTF2IRD1. Thus, it could not explain this current index's causative link to craniosynostosis. Still, it is so essential that further genetic-related phenotypic studies should be organised to better understand the linkage of genotype and phenotype in WS. CONCLUSIONSSurgical release of the abnormally fused cranial suture is advocated in WS children with low anaesthetic risks. We recommend screening CT and magnetic resonance imaging studies to evaluate both parenchymal and calvarial abnormalities in WS. Multidisciplinary team care is mandated in WS management.