[Experimental study of orbital volume using computer assisted technology].

PURPOSE: To evaluate the accuracy of the Simplant analytic software for orbital volumetric measurement. METHODS: The volume of 10 orbits from 5 skulls was evaluated with the Simplant analytic software, and compared with the volume obtained by direct measurement using the water displacement method. The accuracy of volume measurement using Simplant software was assessed statistically by paired t test with SAS6.12 software package. RESULTS: The mean volume was found to be (28.82+/-1.65)ml by direct impression and (28.81+/-1.65)ml by the Simplant analytic software. There was no significant difference between the two methods (P>0.05). The correlation between the techniques was found to be high (r=0.971). CONCLUSION: The Simplant analytic software for orbital volumetric measurement is a simple and accurate method. Supported by Shanghai Leading Academic Discipline Project (Grant No.Y0203).

[A retrospective study of 1420 oral and maxillofacial traumatic cases].

PURPOSE: This clinical retrospective study is aimed to offer the clinical epidemiologic information about oral and maxillofacial trauma based on 1420 cases. METHODS: From 2005-2006, 1420 oral and maxillofacial traumatic cases were treated in Ninth People's Hospital,Shanghai Jiao Tong University School of Medicine. Data regarding age, gender, cause of injury, pattern of fracture and associated systemic injuries were reviewed. RESULTS: The male to female ratio of 1420 cases was 3.24:1;and 36.22% of patients were aged between 20 and 30 years.The most common cause of injury was road traffic accident (42.07%); the zygoma (41.83%) and mandible (29.50%) were the most frequent fracture sites; 43.6% of the cases were not treated or not treated properly in 3 weeks after trauma. CONCLUSIONS: Road traffic accident is the most common cause of hospitalized traumatic cases, and the zygoma and mandible was the susceptible sites to be fractured.Because of the high proportion of inappropriately treated cases,we should take much attention to dentofacial deformities resulting from delayed or inappropriate treatment of oral and maxillofacial trauma cases.

[Mandibular advancement devices assisted UPPP for treatment of obstructive sleep apnea and hypopnea syndrome].

PURPOSE: The purpose of this study is to investigate the mechanics of mandibular advancement devices (MAD) assisted uvulopalatopharyngoplasty (UPPP) for treatment of obstructive sleep apnea and hypopnea syndrome (OSAHS). METHODS: 10 patients (8 males, 2 females) were diagnosed as OSAHS by PSG and operated by UPPP. Mandibular advancement devices was used after operation. One month later, all the patients were evaluated by PSG and cephalometric analysis. Paired t test and correlative analysis were carried out using SPSS 10.0 software package. RESULTS: Cephalometric analysis indicated that MCF, angle C3-Rgn-H, Ant In Mx. Ht were significantly different before and after MAD treatment. AHI was correlative with Ant In Mx. Ht and ratio of tongue area and intermaxillary area(P<0.05). CONCLUSIONS: MAD in patients undergoing UPPP results in changes of mandibular position, instead of changes of enlargement of velopharynx. Supported by Shanghai Leading Academic Discipline Project (Grant No.Y0203).

[Field test and evaluation of landfill performance and structure with evapotranspiration cover].

Water balance performance of an evapotranspiration landfill was studied, considering vegetation structures, soil textile, and soil cover thickness. Results of six experiments showed that the transpiration process played an importance role in controlling water balance in the ET cover system. A nonlinear relationship was established between the transpiration amount and vegetation leaf area index. The evapotranspiration amount was 3.3 to 4.5 times as that of evaporation in the bare soil. In a 60 cm soil profile, the soil water storage capacities were 97.2 mm and 62.8 mm with and without a vegetation cover, respectively. Precipitation infiltration behaved preferentially and heterogeneously, and the preferential flow was the major contribution to percolation. The ratios between maximum and average infiltration depths were 3.65, 1.77, and 1.40, respectively, for 20 mm, 40 mm, and 60 mm of precipitation. Therefore, besides soil textile, soil cover thickness, and the initial water content, precipitation amount was an essential factor affecting the water storage capacity. Numerical simulated results indicated that using a sandy loam as the cover soil was more effective in removing water through evapotranspiration and reducing percolation than using a clay soil.

[A preliminary study of nasoalveolar molding for infants born with cleft lip and palate].

PURPOSE: The purpose of this study was to apply nasoalveolar molding appliance in infants with cleft lip and plate and to observe the preliminary effects on nasal cartilage and columella. METHODS: Ten infants were treated with nasoalveolar molding. The other ten infants without any presurgical orthopedic treatment were chosen as the control group. Each patient was photographed at the initial visit (T0), after nasoalveolar molding (T1), 2 weeks (T2), and half a year (T3) after cheiloplasty. Six measurements were made on the photographs and the nasal symmetry was analyzed with paired t test. RESULTS: The percentage of the deviation from perfect symmetry was significantly improved at T0-T1, T1-T2 stage (P<0.05), and the improvement relapsed at T2-T3 (P<0.05). There was significant difference between the orthopedic group and the control group with the changes in nasal symmetry in vertical dimension (P<0.01), and there was no significant difference in horizontal dimension (P>0.05). CONCLUSIONS: Nasal asymmetry was significantly improved after nasoalveolar molding. Half a year after the primary cheiloplasty, although there was a relapse tendency of nasal asymmetry, the shape of the nasal dome was ideal.

[Distraction osteogenesis for treatment of unilateral temporomandibular joint ankylosis and secondary OSAHS in children: report of 4 cases].

PURPOSE: To evaluate the efficiency of distraction osteogenensis for treatment of unilateral temporomandibular joint ankylosis and secondary OSAHS in children. METHODS: 4 children with temporomandibular joint ankylosis and secondary OSAHS were retrospectively reviewed for their treatment. There were 2 males and 2 females, ranging from 5 to 13 years in age with the median of 6.5 years. Based on the history of the disease, the clinical manifestations, CT scan and PSG findings, the diagnosis was confirmed to be unilateral temporomandibular joint ankylosis and secondary OSAHS. All the patients were treated by gap arthroplasty to restore mouth opening, combined with mandibular body distraction osteogenesis for treatment of OSAHS. One-stage operation was performed on 3 patients, and two-stage operation on 1 patient. Unilateral and bilateral mandibular distraction osteogenesis was undergone on 2 patients individually. At the end of consolidation period of 3 months, the PSG examination was performed again and the distractor was removed. RESULTS: OSAHS was cured, the average AHI was lowered from 42.7 to 4.9, the average lowest saturation of blood oxygen rose from 74.3% to 89.8%, the average incisor distance reached 25.5mm compared to 6.5mm before surgery and facial deformity was corrected satisfactorily. Following up 38.1 months (13-58 months), no relapse appeared. CONCLUSION: Mandibular body distraction osteogenesis, combined with gap arthroplasty, could be the potential treatment modality for children with unilateral temporomandibular joint ankylosis, secondary OSAHS and facial asymmetry; it is recommended that both procedures be performed at the same time.

[Biomechanical study of rigid fixation of the maxillofacial fractures].

Due to the ascending incidence rate of traffic trauma, more and more fractures in oral and maxillofacial region were encountered, which become more severe than before and damage the patient's quality of life and appearance. Biomechanical principles play an extremely important role in treatment of fractures,and study of biomechanical changes of fractured bone before and after rigid internal fixation will improve the effectiveness of therapy. The author summarized the biomechanical studies in the field of rigid internal fixation of fractures in oral and maxillofacial region.

[Histological and ultrastructural variations after radiofrequency for soft palate in porcines].

PURPOSE: To investigate the histological and ultrastructural variations after radiofrequency volumetric reduction of the soft palate in an animal model. METHODS: Thirteen porcines were used to evaluate the tissue response to radiofrequency for various time periods. They were divided into two groups. Group 1 was exposed to radiofrequency in the midline of the soft palate with a constant energy of 2.4 KJ. Group 2 served as a control group. The animals in group 1 were sacrificed after 1 hour, 24 hours, 48 hours, 72 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks and 9 weeks, respectively, and after 72 hours, 2 weeks and 4 weeks for the animals in group 2. Then the soft palates from both groups were examined for histological and ultrastructural variations. RESULTS: Interstitial edema, hemorrhage and infiltration with inflammatory cells were observed in the early acute stage after radiofrequency, and then the neovascularization of the forming scar was observed. In the end, the injured tissue was replaced by collagenous fibers. Intact vessels and nerves were observed around the lesions. CONCLUSIONS: After radiofrequency, lesion tissue is replaced by collagenous fibers, and it is focused on the lesion site. These findings may help provide a basis for technological suggestion in regard to clinical treatment.

[Management of secondary nasolabial deformities after bilateral cleft lip repair].

OBJECTIVE: To evaluate the method to correct the seconary nasolabial deformities after the surgical treatment in the patients with bilateral cleft lip. METHODS: From January 2000 to June 2003, forty patients with secondary deformities following repair of bilateral cleft lip were treated with a combined treatment procedures. AU of the forty cases underwent the following preoperative treatments: alveolar bone graft in 28 cases, preoperative orthodontics in 22 cases, prosthodontics in 20 cases and orthognathic surgery or distraction osteogenesis treatment in 20 cases, respectively. In order to improve the enlongation of nasal column, reconstruction of Cupid's bow, philtrum and correction procedures, continuous incision was made from the vermilion in median of the upper lip, the scar edge, the bilateral sides of the nasal column to the inner side of the nose, even extending the bilateral incision to nasolabial groove and nostril fundus. RESULTS: Forty patients were got the follow-ups for 3 months to 3.5 years and the satisfactory rate reached 95%. CONCLUSION: It is natural to emphasize the setting up of odontomaxillary frame and then utilize the surgical procedure to correct the secondary nasolabial parenchyma deformities. The method could be feasible and reliable for the correction of the secondary nasolabial parenchyma deformities after bilateral cleft lip repair.

[Study of the anatomical location of hypoglossal nerve at tongue base of male adults].

PURPOSE: This study was undertaken to analyze the anatomical location of hypoglossal nerve at tongue base of male adults to avoid creating a function deficit during radiofrequency of tongue base in OSAHS. METHODS: Ten tongues of male adults in frozen were coronally dissected at foramen cecum, 5 mm,10 mm, 15 mm before/after the foramen cecum. Vertical and horizontal distance of hypoglossal nerve to the surface and middle line of the tongue were measured using computer image procession in micrometer. The data were analyzed with such statistical methods as descriptive statistics, paired t-testing, linear correlation analysis. RESULTS: (1) The anatomical location of the bi-lateral hypoglossal nerve is symmetrical in principle. (2) At the tongue base: The distance of hypoglossal nerve to the surface is 22.21+/-2.22 mm, and has no correlation to the length and the width of the tongue. There are some regularities of the anatomical location of the hypoglossal nerve before/after the foramen cecum. Before the foramen cecum the hypoglossal nerve is located in the mid-medial (21.89+/-1.93)% and after the foramen cecum is in the mid-medial (28.61+/-2.66)%. CONCLUSION: We conclude that if the depth of the needle-polar penetrating into the tongue base doesn't exceed (22.21+/-2.22)mm, and keep away from mid-medial (21.89+/-1.93)% ( before the foramen cecum ) or mid-medial (28.61+/-2.66)% after the foramen cecum, it may be helpful to avoid creating a function deficit when radiofrequency tongue base in snoring and OSAHS is performed.

[Combined orthodontic and orthognathic therapy on skeletal class II division 1 malocclusion in adults].

PURPOSE: To Introduce a combined orthodontic and orthognathic method for treatment of skeletal class II division 1 malocclusion in adults. METHODS: In orthodontic-surgical treatment on skeletal class II division 1 malocclusion in adults, the goal of orthodontics was to remove the compensation of upper and lower anterior teeth, leveling Spee's curve, adjusting relationship of the upper and lower dentition arch for intercuspid bite after surgery. The goal of orthodontics before surgery was visual treatment objective (OTV), model surgery and making of bite-plate. To achieve these goals, a combined orthodontic and orthognathic method for treatment of skeletal class II division 1 malocclusion in adults was adopted in this study. RESULTS: Stable function of stomotognathicia and satisfactory facial aesthetics after treatment were obtained. CONCLUSION: Oral and maxillofacial deformity must be treated by combining orthodontic treatment and surgical osteotomy in order to restore oral function and aesthetic appearance.

[Eosinophilic granuloma of the jaw: an analysis of 21 cases].

PURPOSE: To study the clinical features and treatment of eosinophilic granuloma of the jaw (EGJ) in 21 cases. METHODS: 21 patients with EGJ treated from 1983 to 2002 were reviewed, including the sexes, ages, extent of lesions, clinical features and treatment methods. RESULTS: The male to female rate was 13:8. 76% of the cases were among 2-10 years. The median age was 8 years, 18 lesions were in the mandible, 1 was in the maxilla and 2 involved the mandible and maxilla. CONCLUSIONS: EGJ was rarely seen clinically, lack of specificity. Pathology can confirm the diagnosis. Surgery is still the major treatment modality. Combination of radiotherapy or chemotherapy maybe valuable. The prognosis of the patients was generally good.

[Three-dimensional reconstruction on facial soft tissue using three-dimensional grating projection technique].

PURPOSE: The purpose of this study is to establish a method to reconstruct the facial soft tissue three-dimensionally. METHODS: By ATOS three-dimensional opticalmetry, which used in industry, 3D data on facial profile of a patient with mandibular hyperplasia was achieved quickly. RESULTS: Three-dimensional data of facial profile was accurate and the images were reconstructed with verisimilitude. CONCLUSIONS: Traditional device of grating projection was modified by using two CCD cameras to obtain grating images.3D data on facial profile were achieved quickly and accurately.

[Intraosseous neurilemmoma of the jaw: report of 11 consecutive cases].

OBJECTIVE: This study retrospectively analyzed the clinical data of 11 patients with intraosseous neurilemmoma of the jaw, with the purpose of improve its diagnosis and treatment. METHODS: 11 patients with intraosseous neurilemmoma of the jaw treated from January 1993 to February 2002 were reviewed, including the clinical features, pathological findings, immunohistochemical findings, imaging examinations and treatment methods. 8 patients with benign lesions were treated with radical curettage and cautery. 2 patients with mandibular malignant lesions were treated with extended resection and neck dissection. 1 patient with maxillary malignant lesion concomitant with neurofibrostosis was treated with extensive resection and middle split skin graft and neck dissection, followed by chemotherapy and radiotherapy after surgery. RESULTS: The lesions were located in the maxilla in 5 patients (1 was malignant). 6 patients had mandibular lesions (2 were malignant). The X ray findings had some specificity. 10 patients were followed up for 7 to 122 months without recurrence. 1 patient with maxillary malignant lesion died of multiple metastasis 11 months after treatment. CONCLUSIONS: Intraosseous neurilemmoma of the jaw was rarely seen clinically. CT, MRI and fine needle aspiration biopsy were beneficial for early diagnosis. Surgery is still the dominant choice of treatment. The prognosis of the patients was generally good. Adjuvant radiotherapy or chemotherapy had limited value, especially for patients with neurofibrostosis. A novel regime called CYVADICDE was recently invoked much clinical interest.

[Treatment of distraction osteogenesis in the patients of obstructive sleep apnea-hypopnea syndrome with micrognathia].

OBJECTIVE: To apply the treatment of distraction osteogenesis(DO) to obstructive sleep apnea-hypopnea syndrome(OSAHS) patients with croniomaxillofacial deformities. METHODS: All 46 OSAHS patients with micrognathia are had polysomnography(PSG) study and cephalometric analysis. Their age from 4 to 18 years old, the mean age is 11.4. The number of temporal mandibular joint (TMJ) ankylosis with micrognathia, micrognathia; 1st & 2nd bronchial arch syndrome and crouzon syndrome patients were 32, 9, 2 and 3 respectively. All were treated with DO. Maxilla or mandible was advanced from 5 to 35 micrometers; the mean advanced distance is 18.34 mm. They were all revaluated by PSG and cephalometric analysis postoperatively. RESULTS: All patients have good respond to the treatment. They have a better appearance and the narrow upper airway was enlarged remarkably, their AHI drop from 66.31 +/- 14.74 pre-operately to 3.16 +/- 1.70 pro-operately, and minimal posterior airway space(PAS) from (5.48 +/- 2.76) mm to (9.97 +/- 2.05) mm. There is remarkable difference (P < 0.001). CONCLUSION: DO is a good method for the patients of OSAHS with micrognathia.

[CT assist in surgical design for the posterior pharyngeal flap].

OBJECTIVE: To establish a method for assist design of the posterior pharyngeal flap (PPF). METHODS: The width, length of velopharyngeal space in repose and phonation of "i" in 26 cases with VPI were measured with CT. The width and length of PPF needed, the location of the pedicle and the contact position with the soft palate were analyzed. RESULTS: The width of velopharyngeal space in repose ranged from 15.10 to 37.25 mm, with the average of 27.01 mm, the length was 12.54 to 30.39 mm, with the average of 22.10 mm. The width in phonation of "i" was 9.11 to 34.06 mm, with the average of 17.69 mm, the position of the pedicle wasall located at the level of the first cervical vertebra or above and the contact area of the flap with the soft palate was in the middle posterior 1/3 mostly. CONCLUSION: As a method to quantitatively evaluate velopharyngeal function, CT can assist in design for the PPF.

[Stimulation and evaluation on maxillary distraction osteogenesis using CASSOS 2001].

OBJECTIVE: To simulate maxillary distraction osteogenesis and evaluate the change of soft and hard tissue before and after treatment, using Computer-Assisted Simulation System for Orthognathic Surgery( CASSOS 2001). METHODS: A fourteen-year-old boy with severe maxillary hypoplasia, due to unilateral cleft lip and palate, was analysed by cephalometric analysis. The simulations of maxillary distraction osteogenesis (Le Fort I osteotomy and Le Fort II osteotomy) were re-analysed. After the treatment, cephalometric analysis was preformed again. The data were compared. RESULTS: The maxillary hypoplasia was well treated using maxillary distraction osteogenesis; Compared with Le fort I osteotomy, more satisfactory results can be obtained by Le fort I distraction osteogenesis. CONCLUSION: Maxillary distraction osteogenesis is a better way to treat severe maxillary hypoplasia with operated CLP than maxillary osteotomy. CASSOS 2001 can help surgeons and patients on simulation and evaluation of maxillary distraction osteogenesis, and on decision of treatment plan.

[The ratio of soft and hard after bimaxillary operations in patients with skeletal class III malformations].

OBJECTIVE: To study the ratio between soft and hard tissue on the horizontal plane after the operations of maxillary Le Fort I advancement osteotomy and mandibular setback osteotomy in patient with skeletal class III malformations. It can help to predict precisely the post-operational profile. METHODS: 20 patients with skeletal class III malformation were taken cephalometric films pre-and post-operationally. The coordinate of landmarks were given from two films by computer analysis system. Different values in X axis were analysed statistically. RESULTS: All mandibular soft tissue landmarks were correlated with hard tissue landmarks (r<0.5, P>0.05). The ratios were 1:1 except the Pogonion(<1:1). Point of Sn was not correlated with the maxillary hard tissue significantly(r<0.5, P>0.05). CONCLUSION: The poor correlation between maxillary Sn and hard tissue was affected by many factors. It is easy to mark the mandible landmarks clearly. The ratio should help to predict the post-operation profile in patients with skeletal class III malformations.