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PURPOSE: To discuss the application of CAD/CAM technique in the treatment of condylar osteochondroma accompanying with oral-maxillofacial bone deformity. METHODS: Pre-operational planning of a patient with condylar osteochondroma was conducted, maxillary and mandibular bone deformities was performed with CAD technique (Surgicase CMF 5.0 based on CT data), including virtual tumor resection, virtual osteotomy, virtual occlusal plate/osteotomy template designing and post -operative simulation. RP technique was used to make occlusal plates and osteotomy templates. Postoperative CT scan was performed and merged with the operation plans to evaluate the accuracy. RESULTS: Postoperative CT showed the effect of the operation matched with the preoperative planning well. The face of the patient was symmetrical 6 months after operation, there was no sign of recurrence. CONCLUSIONS: The pre -operative application of CAD/CAM technique can improve the accuracy of the tumor resection of the condyle and the correction procedure of facial asymmetry, as well as saving operating time. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (08DZ2271100), Research Fund of Biomedicine Engineering of Shanghai Jiao Tong University (YG2009MS42) and Program for Innovative Research Team of Shanghai Municipal Education Commission. [ABSTRACT FROM AUTHOR]

PURPOSE: To demonstrate temporomandibular joint (TMJ) changes after acute trauma to the mandible without condylar fracture by radiography and surgical exploration. METHODS: Seven patients with 11 joints who had acute trauma to the mandible without condylar fracture complained of mouth opening limitation from 1 month to 1 year after trauma were treated in the temporomandibular joint (TMJ) division of Shanghai Ninth People' s Hospital from 2009 to 2010. Six patients had combined facial fractures which were treated in other hospitals or by other surgeons in this hospital before. CT scans with coronal reconstruction through the condyle immediately after injury and few months later when they came to the TMJ division for treatment were compared. MRI was taken before treatment to check the TMJ changes. Surgical treatment was performed for all patients. RESULTS: CT scan showed 87.5% (7/8) of the joints with "intact" condylar surface bone immediately after injury developed bone destruction 1 month to 1 year later. MRI showed all 11 joints had TMJ disc displaced anteriorly. Ninety percentage (10/11) of the joints also had condylar surface bone destruction. Surgical exploration showed bony ankylosis in 2 joints; fibrous ankylosis with destroyed condyle stuck to the fossa in 3 joints; TMJ osteoarthritis with degenerated condylar surface bone and fibrous adhesion in 5 joints; and internal derangement with relatively normal condylar surface cartilage and disk shape in 1 joint. CONCLUSIONS: Acute trauma [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the usefulness of computer-assisted surgery (navigation and stereolithographic model guided surgery) and compare the results with traditional surgery on the treatment of delayed orbitozygomatic fracture with enophthalmos. METHODS: Sixty-four patients diagnosed as delayed unilateral orbito-zygomatic fractures with enophthalmos were treated in the Department of Oral and Maxillofacial Surgery and Department of Ophthalmology in Shanghai Ninth People's Hospital from October, 2008 to December, 2010. Among them, 25 cases were treated by computer-assisted surgery with the mean enophthalmos of 5.71mm, the other 39 were treated traditionally with the mean enophthalmos of 4.96mm. Materials used for orbital reconstruction were: titanium mesh (n =35); titanium mesh combined with porous polyethylene (Medpor) or hydroxyapatite (HA) (re=12); Medpor (n=12) and HA (n=5). CT scan before and after surgery were acquired with orbital coronal reconstruction and three-dimensional bone reconstruction. Zygomatic reduction and globe projection of different treatment methods were evaluated by post-operative CT scan and clinical follow-up. RESULTS: In computer-assisted surgery, good zygomatic reduction was acquired in 92% of the cases; globe projection was good in 82% of the cases, 17% still had mild enophthalmos (≤3mm). In traditional treated cases, good zygomatic reduction was acquired in 74.3% of the cases; globe projection was good in 74% of the cases, 19% still had mild enophthalmos and 6% had moderate enophthalmos (≤4mm). Good globe projection was acquired in 74% of the cases with titanium mesh only; 83% with combined materials; 67% with Medpor and 20% with HA. CONCLUSION: Computer-assisted surgery can improve the treatment results of delayed orbitozygomatic fracture with enophthalmos. Titanium mesh with Medpor for orbital reconstruction is a good way to treat severe enophthalmos. Supported by the Cooperated Foundation of Medical and Engineering Science of Shanghai Jiao Tong University (40YG2009ZD102), and Pujiang Talent Program of Shanghai Municipality[PJ(2009)00840]. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the role of retaining condylar cartilage on open reduction and internal fixation (ORIF) of intracapsular condylar fracture (ICF) in growing goats by three-dimensional (3D) computed tomography (CT) analysis. METHODS: Twelve 6-month-old goats were randomly divided into two groups, experimental group (n=&) and control group (n=4). ICF was created in bilateral mandibular condyles and then treated with ORIF. One side of the condylar cartilage was retained, while the other side of the condylar cartilage was removed. Condyles in the control group were untouched. CT scans were taken immediately after surgery, 3 months and 6 months post-operation to evaluate the growth of the ramus. Heights of the ramus were measured by 3D-CT analysis. SAS 6.12 software package was used for statistical analysis. RESULTS: Heights of the ramus in cartilage retained group immediately after operation, 3 months and 6 months postoperatively were (42.47±0.99)mm, (51.85±1.67)mm and (56.25±4.49)mm, respectively, while (42.69±0.76)mm, (45.18± 1.31)mm and (46.59±1.66)mm in cartilage removed group, and (42.61±0.99)mm, (51.52±1.95)mm and (56.19±3.38)mm in control group. There were no significant differences between the control group and cartilage retained group (P>0.05). While significant differences were shown between the cartilage retained group and cartilage removed group in both 3 months and 6 months post-operative measurements (P<0.05). CONCLUSION: ORIF for ICF in the growing goats has no effect on condylar growth when the condylar cartilage is retained, but growth restriction occurs when the cartilage is removed. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (08DZ2271100). [ABSTRACT FROM AUTHOR]

PURPOSE: This study was to investigate the classification of traumatic temporomandibular joint ankylosis (TMJA) based on coronal CT scan and to present our treatment experience in the TMJ division of Shanghai Ninth People' s Hospital. METHODS: From 2001 to 2009, 130 patients diagnosed of TMJA were treated in TMJ division. Among them, 84 patients with 124 joints were caused by trauma and treated first by our group of surgeons. They were included in this study. All of them had CT scan, especially coronal reconstruction through the TMJ area before and after surgery. A new classification based on the coronal CT scan was proposed. The treatment protocol for Type Al ankylosis was fibrous tissue release or condylar head resection with costochondral graft (CCG) and temporalis myofascial flap (TMF). For Type A2 and A3 ankylosis, the lateral bony fusion was resected while the intact residual condylar fragment displaced medially was remained. The operation was named "lateral arthroplasty" (LAP). TMF or masseter muscle flap (MMF) was used as a barrier in the lateral gap between temporomandibular joint fossa and stump of the mandibular ramus. If the medial condylar fragment in Type A3 ankylosis was too small to bear the load, it was resected with the bony mass. The joint was then reconstructed with CCG and TMF or MMF. For Type A4 ankylosis, the bony fusion was completely removed and the joint was reconstructed with CCG and TMF or MMF. The result of the treatment were evaluated by CT scan and clinical follow-up. RESULTS: Among the 124 ankylotic joints, 14 were Type Al ankylosis (11.3%); 43 were Type A2 (34.7%); 46 were Type A3 (37.1%) and 21 were Type A4 ankylosis (16.9%). Part of Type Al, all Type A2 and A3 ankylosis had residual condylar head displaced medially which accounted for 75% (93/124) of the TMJ ankylosis. Treatment according to the classification was: LAP for 82 joints (66.1%); CCG for 33 joints (26.6%); and other treatment for 9 joints (7.3%). Forty-eighty patients with 68 joints had long time follow-up from 10 months to 4 years. Among them, 4 out of 17 joints reconstructed with CCG had reankylosis (23.5%), 7 out of 48 joints treated with LAP had reankylosis (14.6%). CONCLUSION: The new classification of TMJ ankylosis based on coronal CT scan is useful and valuable in guiding clinical treatment. LAP with TMF is a good way to treat traumatic TMJ ankylosis when the medially displaced condylar head and disc are intact. CCG with TMF has a good result for Type A4 ankylosis. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (08DZ2271100). [ABSTRACT FROM AUTHOR]