BACKGROUND: The persistence of infection by high-risk human papillomavirus (HPV) may lead to cervical cancer. Recently, the American Society for Colposcopy and Cervical Pathology (ASCCP) announced that oncogenic HPV screening and the PAP smear are the main methods of screening for cervical cancer. The goal of this study was to investigate the prevalence and genotyping of HPV, as well as the risk of cervical dysplasia. METHODS: HPV genotyping was conducted by a commercial chip assay. Cervical dysplasia was retrospectively reviewed using electronic medical records. The study participants were grouped together according to cervical dysplasia status: 'no dysplasia,' 'atypical squamous cells of undetermined significance (ASCUS),' 'low-grade squamous intraepithelial lesion (LSIL),' and 'high-grade squamous intraepithelial lesion (HSIL).' The HPV prevalence and genotyping were analyzed according to the cervical dysplasia group. RESULTS: The overall prevalence of HPV was 17.6% (91 out of 518 patients). HPV-18 (2.3%), HPV-16 (2.1%), and HPV-58 (1.2%) were the three most frequent genotypes. The prevalence of HPV infection and the high-risk HPV positive rate was higher in the ASCUS, LSIL, and HSIL groups than in the no dysplasia group (P<0.05). CONCLUSION: In this study, basic data regarding the prevalence and distribution of HPV genotypes were obtained. Since HPV vaccination has been actively encouraged among Korean women, a change in the prevalence of HPV and cervical dysplasia is expected in the future. This study provided basic data describing the prevalence of HPV and its genotypes in the pre-HPV vaccination era.
Colposcopy ; Electronic Health Records ; Female ; Genotype ; Human papillomavirus 16 ; Human papillomavirus 18 ; Humans ; Mass Screening ; Papillomavirus Infections ; Prevalence ; Retrospective Studies ; Uterine Cervical Neoplasms ; Vaccination

PURPOSE: The aim of this study is to determine whether certain biomaterials have the potential to support cell attachment. After seeding bone marrow stromal cells onto the biomaterials, we investigated their responses to each material in vitro. METHODS: Rat bone marrow derived stromal cells were used. The biomaterials were deproteinized bovine bone mineral (DBBM), DBBM coated with fibronectin (FN), synthetic hydroxyapatite (HA), HA coated with FN, HA coated with beta-tricalcium phosphate (TCP), and pure beta-TCP. With confocal laser scanning microscopy, actin filaments and vinculin were observed after 6, 12, and 24 hours of cell seeding. The morphological features of cells on each biomaterial were observed using scanning electron microscopy at day 1 and 7. RESULTS: The cells on HA/FN and HA spread widely and showed better defined actin cytoskeletons than those on the other biomaterials. At the initial phase, FN seemed to have a favorable effect on cell adhesion. In DBBM, very few cells adhered to the surface. CONCLUSIONS: Within the limitations of this study, we can conclude that in contrast with DBBM not supporting cell attachment, HA provided a more favorable environment with respect to cell attachment.
Actin Cytoskeleton ; Animals ; Biocompatible Materials ; Bone Marrow ; Bone Substitutes ; Calcium Phosphates ; Cell Adhesion ; Durapatite ; Fibronectins ; Mesenchymal Stromal Cells ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Rats ; Seeds ; Stem Cells ; Stromal Cells ; Transplants ; Vinculin

PURPOSE: Micro-computed tomography (micro-CT) has been widely used in the evaluation of regenerated bone tissue but the reliability of micro-CT has not yet been established. This study evaluated the correlation between histomorphometric analysis and micro-CT analysis in performing new bone formation measurement. METHODS: Critical-size calvarial defects were created using a 8 mm trephine bur in a total of 24 Sprague-Dawley rats, and collagen gel mixed with autogenous rat bone marrow stromal cells (BMSCs) or autogenous rat BMSCs transduced by adenovirus containing bone morphogenic protein-2 (BMP-2) genes was loaded into the defect site. In the control group, collagen gel alone was loaded into the defect. After 2 and 4 weeks, the animals were euthanized and calvaria containing defects were harvested. Micro-CT analysis and histomorphometric analysis of each sample were accomplished and the statistical evaluation about the correlation between both analyses was performed. RESULTS: New bone formation of the BMP-2 group was greater than that of the other groups at 2 and 4 weeks in both histomorphometric analysis and micro-CT analysis (P=0.026, P=0.034). Histomorphometric analysis of representative sections showed similar results to histomorphometric analysis with a mean value of 3 sections. Measurement of new bone formation was highly correlated between histomorphometric analysis and micro-CT analysis, especially at the low lower threshold level at 2 weeks (adjusted r2=0.907, P<0.001). New bone formation of the BMP-2 group analyzed by micro-CT tended to decline sharply with an increasing lower threshold level, and it was statistically significant (P<0.001). CONCLUSIONS: Both histomorphometric analysis and micro-CT analysis were valid methods for measurement of the new bone in rat calvarial defects and the ability to detect the new bone in micro-CT analysis was highly influenced by the threshold level in the BMP-2 group at early stage.
Adenoviridae ; Animals ; Bone and Bones ; Bone Regeneration ; Collagen ; Genetic Therapy ; Mesenchymal Stromal Cells ; Osteogenesis ; Rats ; Rats, Sprague-Dawley ; Skull ; X-Ray Microtomography

PURPOSE: The aim of this study was to investigate the immunomodulatory effects of canine periodontal ligament stem cells on allogenic and xenogenic immune cells in vitro. METHODS: Mixed cell cultures consisting of canine stem cells (periodontal ligament stem cells and bone marrow stem cells) and allogenic canine/xenogenic human peripheral blood mononuclear cells (PBMCs) were established following the addition of phytohemagglutinin. The proliferation of PBMCs was evaluated using the MTS assay. The cell division of PBMCs was analyzed using the CFSE assay. The apoptosis of PBMCs was assessed using the trypan blue uptake method. RESULTS: Periodontal ligament stem cells and bone marrow stem cells inhibited the proliferation of allogenic and xenogenic PBMCs. Both periodontal ligament stem cells and bone marrow stem cells suppressed the cell division of PBMCs despite the existence of a mitogen. No significant differences in the percentages of apoptotic PBMCs were found among the groups. CONCLUSIONS: Canine periodontal ligament stem cells have an immunomodulatory effect on allogenic and xenogenic PBMCs. This effect is not a product of apoptosis of PBMCs but is caused by the inhibition of cell division of PBMCs.
Apoptosis ; Bone Marrow ; Cell Culture Techniques ; Cell Division ; Diminazene ; Fluoresceins ; Humans ; Immunomodulation ; Ligaments ; Periodontal Ligament ; Stem Cells ; Succinimides ; Trypan Blue

PURPOSE: Connective tissue reattachment to periodontally damaged root surfaces is one of the most important goals of periodontal therapy. The aim of this study was to develop a root conditioning agent that can demineralize and detoxify the infected root surface. METHODS: Dentin slices obtained from human teeth were treated with a novel root planing agent for 2 minutes and then washed with phosphate-buffered saline. Smear layer removal and type I collagen exposure were observed by scanning electron microscopy (SEM) and type I collagen immunostaining, respectively. Cell attachment and lipopolysaccharides (LPS) removal demonstrated the efficiency of the root conditioning agent. RESULTS: SEM revealed that the smear layer was entirely removed and the dentinal tubules were opened by the experimental gel. Type I collagen was exposed on the surfaces of the dentin slices treated by the experimental gel, which were compared with dentin treated with other root planing agents. Dentin slices treated with the experimental gel showed the highest number of attached fibroblasts and flattened cell morphology. The agar diffusion assay demonstrated that the experimental gel also has effective antimicrobial activity. Escherichia coli LPS were effectively removed from well plates by the experimental gel. CONCLUSIONS: These results demonstrated that this experimental gel is a useful tool for root conditioning of infected root surfaces and can also be applied for detoxification of ailing implant surface threads.
Agar ; Collagen ; Collagen Type I ; Connective Tissue ; Dentin ; Diffusion ; Drugs, Chinese Herbal ; Escherichia coli ; Fibroblasts ; Humans ; Lipopolysaccharides ; Microscopy, Electron, Scanning ; Root Planing ; Smear Layer ; Tooth

PURPOSE: The purpose of this study was to compare the bone regeneration effects of cortical, cancellous, and cortico-cancellous human bone substitutes on calvarial defects of rabbits. METHODS: Four 8-mm diameter calvarial defects were created in each of nine New Zealand white rabbits. Freeze-dried cortical bone, freeze-dried cortico-cancellous bone, and demineralized bone matrix with freeze-dried cancellous bone were inserted into the defects, while the non-grafted defect was regarded as the control. After 4, 8, and 12 weeks of healing, the experimental animals were euthanized for specimen preparation. Micro-computed tomography (micro-CT) was performed to calculate the percent bone volume. After histological evaluation, histomorphometric analysis was performed to quantify new bone formation. RESULTS: In micro-CT evaluation, freeze-dried cortico-cancellous human bone showed the highest percent bone volume value among the experimental groups at week 4. At week 8 and week 12, freeze-dried cortical human bone showed the highest percent bone volume value among the experimental groups. In histologic evaluation, at week 4, freeze-dried cortico-cancellous human bone showed more prominent osteoid tissue than any other group. New bone formation was increased in all of the experimental groups at week 8 and 12. Histomorphometric data showed that freeze-dried cortico-cancellous human bone showed a significantly higher new bone formation percentile value than any other experimental group at week 4. At week 8, freeze-dried cortical human bone showed the highest value, of which a significant difference existed between freeze-dried cortical human bone and demineralized bone matrix with freeze-dried cancellous human bone. At week 12, there were no significant differences among the experimental groups. CONCLUSIONS: Freeze-dried cortico-cancellous human bone showed swift new bone formation at the 4-week healing phase, whereas there was less difference in new bone formation among the experimental groups in the following healing phases.
Animals ; Bone Matrix ; Bone Regeneration ; Bone Substitutes ; Humans ; Osteogenesis ; Rabbits ; X-Ray Microtomography

PURPOSE: It has been reported that low-level semiconductor diode lasers could enhance the wound healing process. The periodontal ligament is crucial for maintaining the tooth and surrounding tissues in periodontal wound healing. While low-level semiconductor diode lasers have been used in low-level laser therapy, there have been few reports on their effects on periodontal ligament fibroblasts (PDLFs). We performed this study to investigate the biological effects of semiconductor diode lasers on human PDLFs. METHODS: Human PDLFs were cultured and irradiated with a gallium-aluminum-arsenate (GaAlAs) semiconductor diode laser of which the wavelength was 810 nm. The power output was fixed at 500 mW in the continuous wave mode with various energy fluencies, which were 1.97, 3.94, and 5.91 J/cm2. A culture of PDLFs without laser irradiation was regarded as a control. Then, cells were additionally incubated in 72 hours for MTS assay and an alkaline phosphatase (ALPase) activity test. At 48 hours post-laser irradiation, western blot analysis was performed to determine extracellular signal-regulated kinase (ERK) activity. ANOVA was used to assess the significance level of the differences among groups (P<0.05). RESULTS: At all energy fluencies of laser irradiation, PDLFs proliferation gradually increased for 72 hours without any significant differences compared with the control over the entire period taken together. However, an increment of cell proliferation significantly greater than in the control occurred between 24 and 48 hours at laser irradiation settings of 1.97 and 3.94 J/cm2 (P<0.05). The highest ALPase activity was found at 48 and 72 hours post-laser irradiation with 3.94 J/cm2 energy fluency (P<0.05). The phosphorylated ERK level was more prominent at 3.94 J/cm2 energy fluency than in the control. CONCLUSIONS: The present study demonstrated that the GaAlAs semiconductor diode laser promoted proliferation and differentiation of human PDLFs.
Alkaline Phosphatase ; Blotting, Western ; Cell Proliferation ; Extracellular Signal-Regulated MAP Kinases ; Fibroblasts ; Humans ; Low-Level Light Therapy ; Lasers, Semiconductor ; Periodontal Ligament ; Phosphotransferases ; Semiconductors ; Tooth ; Wound Healing

PURPOSE: To prolong the degradation time of collagen membranes, various cross-linking techniques have been developed. For cross-linking, chemicals such as formaldehyde and glutaraldehyde are added to collagen membranes, but these chemicals could adversely affect surrounding tissues. The aim of this study is to evaluate the ability of porous non-chemical cross-linking porcine-derived collagen nanofibrous membrane to enhance bone and associated tissue regeneration in one-wall intrabony defects in beagle dogs. METHODS: The second and third mandibular premolars and the first molars of 2 adult beagles were extracted bilaterally and the extraction sites were allowed to heal for 10 weeks. One-wall intrabony defects were prepared bilaterally on the mesial and distal side of the fourth mandibular premolars. Among eight defects, four defects were not covered with membrane as controls and the other four defects were covered with membrane as the experimental group. The animals were sacrificed 10 weeks after surgery. RESULTS: Wound healing was generally uneventful. For all parameters evaluating bone regeneration, the experimental group showed significantly superior results compared to the control. In new bone height (NBh), the experimental group exhibited a greater mean value than the control (3.04 +/- 0.23 mm/1.57 +/- 0.59, P = 0.003). Also, in new bone area (NBa) and new bone volume (NBv), the experimental group showed superior results compared to the control (NBa, 34.48 +/- 10.21% vs. 5.09 +/- 5.76%, P = 0.014; and NBv, 28.04 +/- 12.96 vs. 1.55 +/- 0.57, P = 0.041). On the other hand, for parameters evaluating periodontal tissue regeneration, including junctional epithelium migration and new cementum height, there were no statistically significant differences between two groups. CONCLUSIONS: Within the limitations of this study, this collagen membrane enhanced bone regeneration at one-wall intrabony defects. On the other hand, no influence of this membrane on periodontal tissue regeneration could be ascertained in this study.
Absorbable Implants ; Adult ; Animals ; Bicuspid ; Bone Regeneration ; Collagen ; Dental Cementum ; Dogs ; Epithelial Attachment ; Formaldehyde ; Glutaral ; Guided Tissue Regeneration ; Hand ; Humans ; Membranes ; Molar ; Regeneration ; Wound Healing

PURPOSE: The healing process following tooth extraction apparently results in a pronounced resorption of the alveolar ridge. As a result, the width of alveolar ridge is reduced and severe alveolar bone resorption occurs. The purpose of this experiment is to clinically and histologically evaluate the results of using horse-derived bone mineral for socket preservation. METHODS: The study comprised 4 patients who were scheduled for extraction as a consequence of severe chronic periodontitis or apical lesion. The extraction was followed by socket preservation using horse-derived bone minerals. Clinical parameters included buccal-palatal width, mid-buccal crest height, and mid-palatal crest height. A histologic examination was conducted. RESULTS: The surgical sites healed uneventfully. The mean ridge width was 7.75 +/- 2.75 mm at baseline and 7.00 +/- 2.45 mm at 6 months. The ridge width exhibited no significant difference between baseline and 6 months. The mean buccal crest height at baseline was 7.5 +/- 5.20 mm, and at 6 months, 3.50 +/- 0.58 mm. The mean palatal crest height at baseline was 7.75 +/- 3.10 mm, and at 6 months, 5.00 +/- 0.82 mm. There were no significant differences between baseline and 6 months regarding buccal and palatal crest heights. The amount of newly formed bone was 9.88 +/- 2.90%, the amount of graft particles was 42.62 +/- 6.57%, and the amount of soft tissue was 47.50 +/- 9.28%. CONCLUSIONS: Socket preservation using horse-derived bone mineral can effectively maintain ridge dimensions following tooth extraction and can promote new bone formation through osteoconductive activities.
Alveolar Process ; Bone Resorption ; Bone Substitutes ; Chronic Periodontitis ; Humans ; Minerals ; Osteogenesis ; Tooth Extraction ; Tooth Socket ; Transplants

PURPOSE: This study was performed to evaluate the periodontal wound healing effect of particulate equine bone mineral on canine alveolar bone defects. METHODS: Twelve adult male beagle dogs were used as study subjects. The mandibular second and fourth premolars were extracted prior to the experimental surgery, and the extraction sites were allowed to heal for 8 weeks. After periodontal probing, two-walled defects were created at the mesial and distal sides of the mandibular third premolars bilaterally, and the defects were filled with equine particulate bone with collagen membrane or bovine particulate bone with collagen membrane, or collagen membrane alone. The defects without any treatment served as negative controls. After probing depth measurement, animals were sacrificed at 10, 16, and 24 post-surgery weeks for micro-computed tomographic and histomorphometric analysis. RESULTS: The equine particulate bone-inserted group showed significantly decreased values of probing depth and first bone contact compared to the negative control and collagen membrane alone groups at weeks 10, 16, and 24 (P < 0.05). There were no significant differences in the new cementum length, newly-formed bone area, or newly-formed bone volume between equine particulate bone- and bovine particulate bone-inserted groups, both of which showed significantly increased values compared to the negative control and collagen membrane alone groups (P < 0.05). CONCLUSIONS: Equine particulate bone showed significant differences in probing depth, first bone contact, new cementum length, newly formed bone area, and bone volume fraction values when compared to the negative control and collagen membrane alone groups. There were no significant differences between equine and bovine particulate bone substitutes in these parameters; therefore, we can conclude that equine particulate bone is equivalent to bovine bone for periodontal regeneration.
Adult ; Alveolar Bone Loss ; Animals ; Bicuspid ; Bone Substitutes ; Collagen ; Dental Cementum ; Dogs ; Humans ; Male ; Membranes ; Regeneration ; Transplantation, Heterologous ; Wound Healing ; X-Ray Microtomography