The clinical application of the three-dimensional radiographic technique had been limited to standard Broadbent-Bolton cephalometer with biplanar stereoradiography. We developed a new method for compensating the error of head position in ordinary non-biplanar cephalostat. It became to possible to use the three dimensional cephalogram commonly in clinical bases. 1. The method of methemetical compensation of head positioning error in non-biplanar condition was evaluated with dry skull. The error of the method of first and the second trial was 0.46+/-1.21, 0.33+/-0.90mm, which means the error of the head positioning correction in conventional cephalogram was within clinical acceptance. 2. The reproducibility of this system for clinical application was 0.54 mm (-2.99~2.26mm) which defines the absolute mean difference of the first and second trial. Compare to the The landmark identification error 1.2+/-1.6mm, the error of the measurement was within the range of landmark identification error. The result indicates the adequate clinical accuracy of the computation of three-dimensional coordinates by compensation of the error of the head position in ordinary non-biplanar cephalostat.
Compensation and Redress* ; Head* ; Skull

OBJECTIVE: To evaluate and compare the rate and etiologies of second trimester pregnancy loss in monochorionic (MC) or dichorionic (DC) twins, and natural or assisted reproductive technology (ART) twins. METHODS: Between January 1997 and December 2008, there were 146 cases of second trimester twin pregnancy losses (between 12 and 24 weeks gestation) from 2,467 twin pregnancies. They were divided into four groups according to chorionicity and fertilization. Chorionicity was established by ultrasound at early gestation and confirmed by histologic examination after delivery. From a total of 2,467 twin deliveries, 392 MC, 2058 DC, and 17 unknown chorionicity were observed. Fertilization methods were classified as 736 natural, 1,590 ART, and 141 unknown conceptions. The pregnancy loss rate and possible mechanisms were compared in each group. RESULTS: During the study period, there were 43 MC, 86 DC, and 17 unknown chorionicities and 45 natural, 78 ART, and 23 unknown fertilizations. Total twin pregnancy loss rate was 5.9% (146/2,467), with 11.0% (43/392) and 4.2% (86/2,058) for MC twin group and DC twin group, respectively. Likewise, it was 6.1% (45/736) and 4.9% (78/1,590) for natural twin group and ART twin group. The most common cause was intrauterine fetal death (IUFD) in 22 (51.2%) in MC twin group and preterm premature rupture of membranes (PPROM) in 40 (46.5%) in DC twin group, followed by preterm labor (PTL) in 37 (43%). In natural pregnancy, IUFD was the most common etiology in 20 (44.5%) and for ART twin group, it was PTL in 35 (44.9%). CONCLUSION: Twin pregnancy loss rate was higher in MC twin group compared with DC twin group in the second trimester. MC twin group had a higher incidence of IUFD as a cause of second trimester pregnancy loss. The etiologies in DC twin group were PPROM and PTL. It is suggested that antenatal care in twin pregnancy should be explored for preventing fetal loss and promoting neonatal well-being.
Chorion ; Female ; Fertilization ; Fetal Death ; Humans ; Incidence ; Membranes ; Obstetric Labor, Premature ; Pregnancy ; Pregnancy Trimester, Second ; Pregnancy, Twin ; Reproductive Techniques, Assisted ; Rupture ; Twins

A calcifying epithelial odontogenic tumor (CEOT) was first described as a separate entity in 1955 by Pindborg, and has since been referred to as Pindborg tumor. CEOT is characterized by the presence of squamous-cell proliferation, calcification and amyloid deposits, and accounts for only 1% of all odontogenic tumors. CEOT is a benign, though occasional locally invasive, slow-growing neoplasm. It is located either intraosseously or extraosseously, and is usually associated with an unerupted permanent tooth. A 24 year-old female visited our clinic, presenting with a palatal swelling and intra-oral ulcer. After an incisional biopsy, the lesion was confirmed to be odontogenic tumor. A tumor resection and reconstruction surgery with tongue flap were performed.
Biopsy ; Female ; Humans ; Jaw Neoplasms ; Odontogenic Tumors ; Palate ; Plaque, Amyloid ; Skin Neoplasms ; Tongue ; Ulcer

BACKGROUND: The delivery of growth factors using a carrier system presents a promising and innovative tool in tissue engineering and dentistry today. Two of the foremost bioactive factors, bone morphogenetic protein-2 and vascular endothelial growth factor (VEGF), are widely applied using a ceramic scaffold. The aim of this study was to determine the use of hydroxyapatite microcarrier (MC) for dual delivery of osteogenic and angiogenic factors to accelerate hard tissue regeneration during the regenerative process. METHODS: Two MCs of different sizes were fabricated by emulsification of gelatin and alpha-tricalcium phosphate (a-TCP).The experimental group was divided based on the combination of MC size and growth factors. For investigating the in vitro properties, rat mesenchymal stem cells (rMSCs) were harvested from bone marrow of the femur and tibia. For in vivo experiments, MC with/without growth factors was applied into the standardized, 5-mm diameter defects, which were made bilaterally on the parietal bone of the rat. The animals were allowed to heal for 8 weeks, and samples were harvested and analyzed by microcomputed tomography and histology. RESULTS: Improved proliferation of rat mesenchymal stem cells was observed with VEGF loaded MC. For osteogenic differentiation, dual growth factors delivered by MC showed higher osteogenic gene expression, alkaline phosphatse production and calcium deposition. The in vivo results revealed statistically significant increase in new bone formationwhen dual growth factors were delivered by MC. Dual growth factors administered on a calcium phosphate matrix showed significantly enhanced osteogenic potential. CONCLUSION We propose this system has potential clinical utility in providing solutions for craniofacial bone defects, with the added benefit of early availability.

BACKGROUND: The delivery of growth factors using a carrier system presents a promising and innovative tool in tissue engineering and dentistry today. Two of the foremost bioactive factors, bone morphogenetic protein-2 and vascular endothelial growth factor (VEGF), are widely applied using a ceramic scaffold. The aim of this study was to determine the use of hydroxyapatite microcarrier (MC) for dual delivery of osteogenic and angiogenic factors to accelerate hard tissue regeneration during the regenerative process. METHODS: Two MCs of different sizes were fabricated by emulsification of gelatin and alpha-tricalcium phosphate (a-TCP).The experimental group was divided based on the combination of MC size and growth factors. For investigating the in vitro properties, rat mesenchymal stem cells (rMSCs) were harvested from bone marrow of the femur and tibia. For in vivo experiments, MC with/without growth factors was applied into the standardized, 5-mm diameter defects, which were made bilaterally on the parietal bone of the rat. The animals were allowed to heal for 8 weeks, and samples were harvested and analyzed by microcomputed tomography and histology. RESULTS: Improved proliferation of rat mesenchymal stem cells was observed with VEGF loaded MC. For osteogenic differentiation, dual growth factors delivered by MC showed higher osteogenic gene expression, alkaline phosphatse production and calcium deposition. The in vivo results revealed statistically significant increase in new bone formationwhen dual growth factors were delivered by MC. Dual growth factors administered on a calcium phosphate matrix showed significantly enhanced osteogenic potential. CONCLUSION We propose this system has potential clinical utility in providing solutions for craniofacial bone defects, with the added benefit of early availability.

Child ; Decompression ; Dentigerous Cyst ; Depression ; Humans ; Jaw ; Paresthesia ; Tooth ; Traction