STATEMENT OF PROBLEM: Resonance frequency analysis has been increasingly served as a noninvasive and objective method for clinical monitoring of implant stability. Many clinical studies must be required for standardized data using RFA. PURPOSE: This study was performed to evaluate RFA value changes in two anodized implant groups. MATERIAL AND METHOD: Among a total of 24 implants, twelve screw shaped implants as a test group (H2-R8.5) were manufactured, which had a pitch-height of 0.4 mm, an outer diameter of 4.3 mm, a length of 8.5 mm, and external hexa-headed, were turned from 5 mm rods of commercially pure titanium (ASTM Grade IV, Warantec Co., Seoul, Korea), and another twelve implants as a control group were Branemark Ti-Unite MK4 (diameter 4.0 mm, length 8.5 mm). Each group was installed in tibia of rabbit. Two implants were placed in each tibia (four implants per rabbit). Test two implants were inserted in right side and control two in left side. ISQ values were measured using Osstell(TM) (Integration Diagnostics Ltd. Sweden) during fixture installation, and 12 weeks later and evaluated the RFA changes. RESULTS: Mean and SD of baseline ISQ values of test group were 75.0 +/- 3.4 and 68.7 +/- 8.1 for control group. Mean and SD of ISQ values 12 weeks after implant insertion were 73.2 +/- 4.7 for test group and 72.6 +/- 3.9 for control group. There were no statistically significant differences between groups in ISQ values after 3months (P>0.05). From the data, RFA gains after 3 months were calculated, and there was statistically significant difference between groups (P<0.05). CONCLUSION: Although there were RFA changes between groups, implant stability after experimental period shows alike tendency and good bone responses.
Seoul ; Tibia ; Titanium

BACKGROUND: It is not yet clear whether the abnormal cytokine production in relation to serum IgE levels in atopic dermatitis (AD) is associated with the amount of mRNA of cytokine gene. OBJECTIVE: Our purpose was to delineate the effect of reciprocal correlation in the level of mRNA between interleukin-4 (I") and interferon-gamma (IFN-γ) in severe AD. METHODS: We examined 15 cases including 5 AD patients with high serum IgE (>2,000 kU/liter), 5 AD patients with low serum IgE (<100 kU/liter), and 5 healthy controls. Using semi quantitative reverse transcription-polymerase chain reaction, IL-4 and IFN-γ gene expressions in peripheral mononuclear cells (PBMC) were examined. RESULTS: 1) IL-4 gene expression in spontaneous PBMC was higher in AD patient groups than in control group, significantly higher only in AD patient group with high serum IgE level (p < 0.05). 2) IFN-γ gene expression in spontaneous PBMC showed increased tendency in AD patient groups than in control group without statistical significance. 3) IL-4 and IFN-γ gene expressions in stimulated PBMC were not different among all three groups. CONCLUSION: In light of our results, high and low IgE subgroups in AD can exist and AD may not be R characterized by the shift in the reciprocal relationship between IL-4 and IFN-γ when T cells are stimulated under antigen presenting cell-independent conditions.
Dermatitis, Atopic ; Gene Expression ; Humans ; Immunoglobulin E* ; Interferon-gamma* ; Interleukin-4* ; RNA, Messenger ; T-Lymphocytes

The posterior cruciate ligament is an anatomically and biomechanically complex structure. PCL injuries are reported to occur in 1-40% of acute knee injuries, with isolated PCL tear, less common than PCL tears combined with other Iigament injuries. Controversy exists concerning the geatment of the PCL injures. Recently, arthroscopic techniques of PCL reconstruction are becoming nore refined and reproducible. Between July 1993 and May 1995, 25 operations for PCL rupture were performed in our hospital. At the follow-up examinations we noted mild to moderate posterior instablilty which was not noted at the time of operation and during the immediate postoperative period. We reviewed type (if injuries, amplitude of initial posterior tibia1 translation, surgical techniques, which seemcd to be in relation ivith the postoperative instabilities. At final follow-up, the mean Lysholm knee score was 86 points, and the posterior tibial translation 6.5mm on posterior stress radiographs. The ligament augmentation device provided no benefit. The ideal positioning and fixation of the graft and protection of the graft from abrasion seemed to be important to get a good results.
Follow-Up Studies ; Knee ; Knee Injuries ; Ligaments ; Patellar Ligament* ; Posterior Cruciate Ligament ; Postoperative Period ; Rupture ; Transplants*

Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.
Cell Culture Techniques ; Collagen ; Finite Element Analysis

Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.
Cell Culture Techniques ; Collagen ; Finite Element Analysis

No abstract available.

The objective of this study was to evaluate the effect a chewable tablet containing sodium flouride and lauroyl sodium sulfate on removing plaque and inhibiting gingival inflammation. A randomized parallel study was designed. 100 voluteers participated in the study. There were two test groups each with 30 subject. Test group A was instructed to brush once in the morning, and to use the tablet once in the afternoon and once in the evening. Test group B was instructed to use the tablet three times a day without brushing. There were two control groups each with 20 subjects. Control group A was instructed to brush once in the morning only. Control group B was instructed not to brush all. Two weeks before the test period, the subjects received through tooth cleaning and polishing. At baseline, GI, PI, BOP, and GCF of the Ramfjord teeth were measured in all groups. Bacteria culture was done with the plaque sampled from tooth with the deepest pocket. After 5 days, clinical indices were measured and the bacterial culture was repeated. Control group B was dropped from the study after this period. All the other groups remained and the indices and the culture was repeated after 2 weeks, and 3weeks. Also whether the oral mucosa showed signs of irritation was monitored throughout the test period. Test group A showed less PI, GI, BOP, probing depth, GCF than test group B or control group A. Especially, PI and the BOP was significantly less than that of the group that was instructed to brush once a day. This implies that the added use of this tablet aids in plaque removal in people who brush just once a day. Test group A showed increase of cocci, decrease of motile rods, and decrease of spirochetes after 14-21 days. And this was significantly different from the control group A. At no time of the test period did any of the subjects show signs of irritation of the oral mucosa or adverse reactions. Following conclusions could be obtained from this study. This chewable tablet for enhanced oral hygiene could be used as an adjunct to oral hygiene in people who do not brush adequately. The use of this tablet decreased the number of subgingival bacteria, and this could be effective in plaque removal and for prevention of gingival inflammation.
Bacteria ; Dental Plaque ; Gingivitis ; Inflammation* ; Mouth Mucosa ; Oral Hygiene ; Periodontitis ; Sodium Fluoride* ; Sodium* ; Spirochaetales ; Tooth

The importance of soft tissue response to implant abutments has become one of the major issues in current implant dentistry. To date, numerous studies have emphasized on maintaining connective tissue barriers in quantity, as well as in quality for the long term success of dental implants. The cells mainly consisting the soft tissue around dental implants are fibroblasts and epithelial cells. The mechanism of the fibroblasts'adhesions to certain substrata can be explained by the 'focal adhesion'theory. On the other hand, epithelial cells adhere to the substratum via hemidesmosomes. The typical integrin-mediated adhesions of cells to certain matrix are called 'cell-matrix adhsions'. The focal adhesion complex of fibroblasts, in relation to the cell-matrix adhsions, consists of the extracellular matrix(ECM) such as fibronectin, the transmembrane proteins such as integrins, the intracellular cytoplasmic proteins such as vinculin, talin, and more, and the cytoskeletal structures such as filamentous actin and microtubules. The mechanosensory function of integrins and focal adhesion complexes are considered to play a major role in the cells'adhesion, migration, proliferation, differentiation, division, and even apoptosis. The '3-D matrix adhesions'defined by Cukierman et al. makes a promising future for the verification of the actual process of the cell-matrix adhesions in vivo and can be applied to the field of implant dentistry in relation to obtaining strong soft tissue attachment to the implant abutments.
Actins ; Apoptosis ; Cell-Matrix Junctions* ; Connective Tissue ; Cytoplasm ; Dental Implants* ; Dentistry ; Epithelial Cells ; Fibroblasts ; Fibronectins ; Focal Adhesions ; Hand ; Hemidesmosomes ; Integrins ; Microtubules ; Talin ; Vinculin

The importance of soft tissue response to implant abutments has become one of the major issues in current implant dentistry. To date, numerous studies have emphasized on maintaining connective tissue barriers in quantity, as well as in quality for the long term success of dental implants. The cells mainly consisting the soft tissue around dental implants are fibroblasts and epithelial cells. The mechanism of the fibroblasts'adhesions to certain substrata can be explained by the 'focal adhesion'theory. On the other hand, epithelial cells adhere to the substratum via hemidesmosomes. The typical integrin-mediated adhesions of cells to certain matrix are called 'cell-matrix adhsions'. The focal adhesion complex of fibroblasts, in relation to the cell-matrix adhsions, consists of the extracellular matrix(ECM) such as fibronectin, the transmembrane proteins such as integrins, the intracellular cytoplasmic proteins such as vinculin, talin, and more, and the cytoskeletal structures such as filamentous actin and microtubules. The mechanosensory function of integrins and focal adhesion complexes are considered to play a major role in the cells'adhesion, migration, proliferation, differentiation, division, and even apoptosis. The '3-D matrix adhesions'defined by Cukierman et al. makes a promising future for the verification of the actual process of the cell-matrix adhesions in vivo and can be applied to the field of implant dentistry in relation to obtaining strong soft tissue attachment to the implant abutments.
Actins ; Apoptosis ; Cell-Matrix Junctions* ; Connective Tissue ; Cytoplasm ; Dental Implants* ; Dentistry ; Epithelial Cells ; Fibroblasts ; Fibronectins ; Focal Adhesions ; Hand ; Hemidesmosomes ; Integrins ; Microtubules ; Talin ; Vinculin

No abstract available.
Humans* ; Mesenchymal Stromal Cells*