[A clinical study on reparation of orbital blowout fracture by bridge hydroxylapatite artificial bone].

OBJECTIVE: To explore a minimally invasive technique with hydroxylapatite artificial bone to repair the orbital blowout fracture. METHODS: Twenty-one cases of orbital blowout fracture from March 2008 to April 2010 were enrolled. And the fractures were repaired with a bridge of hydroxylapatite artificial bone under a nasal endoscope. During a regular 6-month follow-up, anatomic and functional recovery was evaluated. RESULTS: There was neither postoperative visual loss nor infection in all cases. At 3 months post-operation, diplopia vanished completely (n = 17), remained in peripheral vision (n = 2), existed in primary ocular position (n = 2) and the deviation of eyeball (n = 1). At Month 3, diplopia in peripheral vision or in primary position and the deviation of eyeball showed no improvement. Compared with the uninjured side, enophthalmos: ≤ 2 mm (n = 18), > 2 mm (n = 2) and > 4 mm (n = 1). The passive traction test was positive in one case. On computed tomograph (CT) scanning, there was no bone dislocation or slippage in all cases. CONCLUSION: The surgical efficacy is excellent. The technique of combining the advantages of endoscopic sinus approach and hydroxyapatite artificial bone is worth a wider popularization.

Evaluation of SORD mutations as a novel cause of Charcot-Marie-Tooth disease.

Biallelic mutations in the sorbitol dehydrogenase (SORD) encoding gene were recently identified as a common genetic cause in autosomal-recessive CMT patients. Here, we investigated the clinical, genetic, and electrophysiological characteristics of three CMT patients with biallelic SORD mutations from a Chinese cohort. Two patients harbored c.757delG (p.A253Qfs*27) homozygous mutations, and one patient carried both c.757delG (p.A253Qfs*27) and c.625C>T (p.R209X) compound heterozygous mutations. Interestingly, the two patients homozygous for the c.757delG mutation exhibited positive responses for pinprick test. In conclusion, we confirmed SORD mutations as causative for CMT and further expanded the mutational and phenotypic spectrum of SORD-related CMT.

[Treatment of adult bimaxillary arch protrusion with micro-implant anchorage].

PURPOSE: In this study, micro-implants were used in 15 adult patients with mild and moderate bimaxillary arch protrusion or crowding. Cephalometric analysis was used to analyze hard and soft-tissues change before and after treatment, with the aim to investigate the effects of treatment on adult bimaxillary arch protrusion with micro-implant anchorage. METHODS: Fifteen adult patients with mild and moderate bimaxillary arch protrusion were selected in this study. Micro-implants were inserted into the zygomaticoalveolar ridge of maxilla and the external oblique line of mandible. A NiTi coil spring was attached to the micro-implant to drag the whole upper and lower dentition for distal movement. Cephalometrics were taken before and after treatment, and the changes of soft and hard-tissue profile were studied. SPSS13.0 software package was used to analyze the data. RESULTS: (1)Sixty micro-implants remained stable.(2)SNA, SNB had no significant changes (P>0.05), and the relationship between the maxilla and the mandible did not change significantly. U1/NA, U1-NA, L1/NB, L1-NB and U1/L1 changes in hard tissue had significant difference in cephalometric measurement (P<0.05). The upper and lower anterior teeth were more retrusive, and the tipping of incisor decreased significantly.(3)Cephalometric analysis showed that lateral appearance improved and soft tissue cephalometric-related measurements such as Cm-Sn-UL,LL-B'-Pos increased significantly (P<0.01). (4)Molars and incisors acquired distal movement. CONCLUSIONS: Micro-implant can provide not only excellent skeletal anchorage but also a novel way to distalize the whole dentition efficiently.

[Histological changes of craniofacial sutures after retractive forces with zygomatic implant anchorage to the maxilla of rhesus monkeys].

PURPOSE: To demonstrate the histological changes of the maxilla-facial sutures caused by retractive forces of a zygomatic implant anchorage to the maxilla of rhesus monkeys. METHODS: Four young male rhesuses were employed, 3 in the experimental group (1 was been distracted for 1.5 months and 2 for 3 months), and 1 as control. HE staining and vital fluorescent were used to observe histological changes in the circum-maxillary sutures (i.e. zygomaticomaxillary suture, transverse palatine suture, frontomaxillary suture and pterygopalatine suture) and the posterior sutures (i.e. zygomaticotemporal suture and sphenozygomatic suture, sphenozygomatic suture) of zygoma bone caused by retractive forces of zygomatic implant to the maxilla of rhesus monkeys. RESULTS: Obvious reactions of compressive stress and bone resorption were observed around the 4 circum-maxillary sutures. There were 3 patterns of sutural reactions, indicating the direction of sutural stress influenced by sutural position and morphology. Reactions of interdigitate wedging were observed in the transverse palatine suture and frontomaxillary suture, showing a bony collision that the tip of bony process and the hollow were resorbed markedly. Phasic reactions were found in the pterygopalatine suture reaction, representing a bony sliding that one side of a bony surface was deposited while the opposite side was resorptive. Both reactions were observed in the zygomaticomaxillary suture. Tensile stresses were observed in the 3 sutures around anchoraged zygoma bone (i.e. zygomaticotemporal suture, sphenozygomatic suture and sphenozygomatic suture) with similar three-pattern reactions. CONCLUSIONS: Histologically, significant changes differing from physiological remodeling are observed in the circum-maxillary sutures and posterior sutures of zygoma bone, but no destructive changes are found. These findings demonstrate that bone resorptions are major reactions caused in the 4 circum-maxillary sutures. Different sutures respond slight histological differences. The maxillary complex is retracted distally with some rotation. Tensile stress occured in the posterior sutures around zygoma bone with a zygomatic implant anchorage, which is different from the effect with a headgear. Supported by Science and Technology Plan Project of Yunnan Province (2007C0029R).

[Nacre-induced osteogenesis in the femoral condyles of New Zealand rabbits].

OBJECTIVE: To evaluate nacre powder-induced osteogensis in the femoral condyles of New Zealand rabbits and investigate the possible mechanism. METHODS: Nacre powder was implanted into the femoral condyles of New Zealand rabbits and 4, 8, and 12 weeks after the implantation, radiographic examinations were carried out and the bone density was evaluated. The bone tissue specimens were sliced after fixation for histological observations. The osteogenesis area on the slice was estimated with Ponceau Red staining 8 and 12 weeks after the implantation and calculated with Imaga-Pro software. RESULTS: X-ray after the operation did not reveal obvious evidence of angiogenesis in the femoral condyles, where the X-ray density underwent slight changes. The optical density decreased significantly after the implantation, and the quantity of the osteoid, woven and lamellar bone increased in the bone tissue with time. The osteogenesis area with Ponceau Red staining showed obvious bone formation, which was significantly different from the control group. CONCLUSION: T Obvious osteogenesis occurred in the femoral condyles after nacre powder implantation in New Zealand rabbits. Nacre powder has slow biodegradation in vivo and induces osteogenesis by osteoinduction.