Treatment of FGF-2 on stem cells from inflamed dental pulp tissue from human deciduous teeth.

OBJECTIVE: The purposes of this study were to isolate and characterize stem cells from inflamed pulp tissue of human functional deciduous teeth (iSHFD) and to evaluate the influence of fibroblastic growth factor-2 (FGF-2) on the regenerative potential. MATERIALS AND METHODS: We successfully isolated mesenchymal stem cells (MSCs) from the inflamed dental pulp tissue of human deciduous teeth and demonstrated that their regenerative potential could be enhanced by the application of FGF-2 (20 ng ml(-1)) during ex vivo expansion. Isolated stem cells expanded in FGF-2 were characterized using a colony-forming assay, proliferation, migration, in vitro differentiation, in vivo ectopic transplantation assay, and gene expression profiling. RESULTS: MSCs isolated from the inflamed pulp tissue of functional deciduous teeth potentially possess the qualities of those from human exfoliated deciduous teeth. FGF-2 applied to iSHFD during expansion enhanced the colony-forming efficiency of these cells, increased their proliferation and migration potential, and reduced their differentiation potential in vitro. However, the ectopic transplantation of iSHFD/FGF-2 in vivo increased the formation of dentin-like material. CONCLUSION: FGF-2 expansion of stem cells from inflamed pulp tissues of human deciduous teeth can be a good source of stem cells for future clinical applications and a novel way of using discarded inflamed tissues.

Efficacy and safety of solifenacin succinate in Korean patients with overactive bladder: a randomised, prospective, double-blind, multicentre study.

PURPOSE: We assessed the efficacy and safety of solifenacin compared with tolterodine for treatment of overactive bladder (OAB) in Korean patients. MATERIALS AND METHODS: The study was randomised, double-blind, tolterodine-controlled trial in Korea. Patients had average frequency of >or= 8 voids per 24 h and episodes of urgency or urgency incontinence >or= 3 during 3-day voiding diary period. Patients were randomised to 12-week double-blind treatment with either tolterodine immediate release (IR) 2 mg twice daily (TOL4) or solifenacin 5 mg (SOL5) or 10 mg (SOL10) once daily. The outcome measure was mean change in daily micturition frequency, volume, daily frequency of urgency incontinence, urgency and nocturia from baseline to week 12. Quality of life was assessed using the King's Health Questionnaire. RESULTS: A total of 357 were randomised and 329 were evaluated for efficacy. All voiding parameters recorded in micturition diary improved after treatment in all three groups. Mean changes in volume voided were 19.30 ml (26.69%) in TOL4, 30.37 ml (25.89%) in SOL5 and 37.12 ml (33.36%) in SOL10 group (p = 0.03). Speed of onset of SOL10 efficacy on urgency incontinence was faster than that of SOL5 and TOL4. Quality of life improved in all three groups. Dry mouth was the most common adverse event; its incidence was the lowest in SOL5 group (7.63%, compared with 19.49% and 18.64% in SOL10 and TOL4 groups respectively). CONCLUSIONS: Solifenacin succinate 5 and 10 mg once daily improve OAB symptoms with acceptable tolerability levels compared with tolterodine IR 4 mg. Solifenacin 5 mg is a recommended starting dose in Korean patients with OAB.

Effects of implant geometry and surface treatment on osseointegration after functional loading: a dog study.

The purpose of this study was to evaluate the geometry and surface characteristics of osseointegration after functional loading by radiographic, periodontal and histomorphometric analyses. We analysed three groups of implants with different geometry and surface characteristics using experimental dogs. The control group received Brånemark implants (group 1). Group 2 and group 3 implants each had a 0.5-mm pitch height but differed in surface characteristics. Group 2 implants were machine surfaced and group 3 implants were thermally oxidized at 800 degrees C for 2 h in a pure oxygen atmosphere. For these experiments, which used a total of four healthy beagle dogs, the implants were randomly installed into the extracted first, second and third premolar positions. The animals received radiographic and clinical periodontal examinations at 6 and 12 months post-loading, and were then killed for histomorphometric analysis. The radiographic analysis showed that mean crestal bone resorption in the control group was greater than that observed in the experimental groups (P < 0.05). The percentage of bone-to-implant contact for group 3 (83.7%) was significantly higher than in groups 1 (74.4%) and 2 (75.0%) (P < 0.05). Overall, implant geometry and surface treatment affected the rate of crestal bone resorption and bone healing surrounding the dental implants.

Optimization of electrospun fibrous membranes for in vitro modeling of blood-brain barrier.

The blood-brain barrier (BBB) plays a critical role in brain homeostasis at the cellular and global level. Mimicking the selective permeability and transport properties of the BBB to specific molecules and cells remains a significant challenge towards the development of a physiologically relevant in vitro BBB model. In this study, we developed electrospun poly (ε-caprolactone) (PCL) and polyethylene glycol (PEG) copolymer membranes that supported different cellular components of the neurovascular unit including human-derived endothelial cells, pericytes and astrocytes. Comparative analyses of thickness, morphology, biocompatibility and permeability of membranes were also conducted. We found that collagen coated 4%PEG-96%PCL membranes supported the growth of a confluent and tight endothelium confirmed by transendothelial electrical resistance measurements (TEER). Based on fabrication process and reported results, we finally discuss the adoption of these electrospun fiber membranes for in vitro and on-a-chip human BBB models.

Combined periodontal-prosthodontic treatment of early-onset periodontitis--an alternative to implant therapy.

A variety of treatment systems should be available for patients whose dentitions are seriously compromised so that they may select customized treatment modalities that satisfactorily restore occlusal function, consider systemic conditions, and lessen the surgical and financial burdens. These requirements become more demanding when clinicians are faced with advanced cases of rapidly progressive periodontitis. Therefore, it is critical to establish sophisticated multidisciplinary treatment modalities for the successful management of these compromised patients. Obviously, because of various limitations, implant therapy cannot be the only solution. This article reports on the successful long-term management of seriously compromised early-onset periodontitis by a combined periodontal-prosthetic treatment as an alternative to implant therapy.

Osseointegration of anodized titanium implants under different current voltages: a rabbit study.

The oxide layer that covers a titanium surface is extremely stable and appears to have excellent biocompatibility, which can result in successful osseointegration. The aim of this study was to analyse the characteristics of an oxide layer formed by anodic oxidation (anodization), and to evaluate the extent of bone healing around the anodized implant. The screw-type implants were made of commercially pure titanium (Grade 2). The Group 1 samples had a turned surface, and three other types of experimental specimens were anodized under constant voltages of 190 V (Group 2), 230 V (Group 3) and 270 V (Group 4). The surface characteristics of each sample type were inspected. Removal torque was measured after a 4-week healing period and the histomorphometric analysis was performed 6 weeks after implantation in rabbit tibiae. There was an increase in both the size and number of pores as the anodizing voltage increased. The Ra value of the Group 4 samples was higher than those in the Group 1 and 2 samples (P < 0.05). Group 3 showed a difference compared with Group 1 (P < 0.05). A thicker oxide layer, which contained crystalline (anatase) TiO(2) with the inclusion of some electrolytes (Ca, P), was formed at the higher anodizing voltage. Group 4 had higher removal torque values and percentages of bone-to-implant contact than the other groups (P < 0.05). The anodized titanium implants showed more intimate and stronger connections with peri-implant bone during early osseointegration than the turned titanium implants in this experimental model.

Biological responses of anodized titanium implants under different current voltages.

The oxide layer of a titanium surface is very stable, and seems to result in excellent biocompatibility and successful osseointegration. The purpose of this study was to investigate the effects of high anodic oxidation voltages on the surface characteristics of titanium implants and the biologic response of rabbit tibiae. Bone tissue responses were evaluated by removal torque tests and histomorphometric analysis. Screw-shaped implants with microthreads were made of commercially pure titanium (Grade II). We prepared anodized implants under 300 V (group I), 400 V (group II), 500 V (group III) and 550 V (group IV). The surface characteristics of specimens were inspected according to three categories: surface morphology, surface roughness and oxide layer thickness. The screw-shaped implants were installed in rabbit tibiae. The removal torque values were measured and histomorphometric analysis was done after 1- and 3-month healing periods. Data indicate that as anodic oxidation voltage increased above 300 V, oxide layer thickness increased rapidly and pore size also increased. The roughness values of the implants increased with voltage up to 500 V, but decreased at 550 V. In the removal torque test, group III showed higher values than groups I and II at a statistically significant level (P < 0.05) after a 1-month healing period. In histomorphometric analysis, groups III and IV, after a 3-month healing period, showed greater bone to implant contact ratios for the total implant surface than did group I (P < 0.05).

An abutment screw loosening study of a Diamond Like Carbon-coated CP titanium implant.

The aim of this study was to quantify the extent of abutment screw loosening and thus understand the role of frictional and wear factors in abutment screw loosening by using a cyclic loading device to compare Diamond Like Carbon (DLC)-coated and non-coated implants. The properties of DLC films, including hardness, wear resistance, chemical stability, and biocompatibility, are similar to those of real diamond materials. In this study, a 1-mum thick DLC film served to protect and lubricate a layer of commercially-pure titanium affixed to the top of a dental implant (external hexagon-shaped implant). A cyclic loading force was then applied to the top of the prosthetic portion of the implants in order to determine the difference in looseness of the titanium abutment screw between ten DLC-coated implants and ten non-coated implants. The abutment screw loosening tests were performed with 100 N of force at a frequency of 20 Hz. Data indicate that implants with a DLC coating are more resistant to an applied force (P = 0.002) than are those without the coating. We hope these results will be useful for preventing implant abutment screw loosening.

[A study on injured policemen in dental field].

In 1989, there were 8893 injured policemen by various demonstrations. This injury ratio (8893/130,000) is about 3 times higher than other occupations. Of them, 2869 (31%) were treated at National Police Hospital, and 13% of which were facial injuries. The most common etiologic factor of facial injuries was demonstrations by Univ. students (89.2%), and 93.9% of the victims were injured by thrown stone.

Impact simulation on pre-formed prosthesis for large cranial defect.

Cranioplasty greater than 10 cm2 in size is challenging task for neurosurgeon. There are many successful trials to fill the small defect with various materials. Proper cranioplasty can provide subsequently restoration of cerebral protection, cosmetic aspect and neuronal function. However, larger defect may not provide adequate protection from the auto, industrial or sport accident even with cranioplasty. In this study, patch design using two popular materials was evaluated and compared with bone material. Then impact-releasing holes were implemented to the patch. The movement of the large patch and its effect on the underlying brain tissue upon simulated impact was evaluated by using finite element analysis.