In periodontal disease, the periodontium is gradually destroyed, along with a decrease in the extracellular matrix. Proteinases are thought to be involved in this destructive process. The objective of this study was to identify the proteinases in human periodontal ligaments with parodontopathy to better characterize destructive processes in the periodontium. Inflammed periodontal ligament was obtained from extracted human teeth with periodontal disease. Human intact periodontal ligament was used as a control. The enzymatic fraction was prepared from each sample in the sample loading buffer for SDS-PAGE, and the proteolytic activities were examined using zymograms and Western blotting (Zymo-Western analysis). An increase in MMP-9 and neutrophil elastase activities was observed in the inflammed periodontal ligament, compared to that in the control ligament. When non-collagenous proteins prepared from porcine intact periodontal ligament (PLNCP) were used as the substrate for the zymogram, only neutrophil elastase activity was detected. On surveying the physiological substrate of the neutrophil elastase in the PLNCP, an acidic protein with a molecular mass of approximately 110 kDa and that stained blue with Stains-all staining was found to be the main product of degradation. SEM observations of PLNCP after neutrophil elastase digestion were similar to those of human inflammed periodontal ligament, with exposed collagen fibrils visible the surface. The PLNCP structure before digestion was similar to that of human intact periodontal ligament. The collagen fibers in the intact periodontal ligament were covered by a complex of non-collagenous proteins. During the destructive processes leading to inflammed periodontal ligament, neutrophil elastase appears to be involved in the initiation of the degradation, of the non-collagenous protein-complex that covers the collagen fibers. J Jpn Soc Periodontol, 45: 22-32, 2003.
Periodontal disease is common in middle age. This study investigated periodontal regeneration using rhBMP-2 in middle-aged beagles. Horizontal periodontal defects at buccal sites were surgically produced, rhBMP-2 combined with polylactate-polyglycolate-copolymer/gelatine sponge complexes (PGS) were then implanted on the planed root surfaces in 6-year-old beagles (MB) and 14-month-old beagles (YB). PGS were implanted in the same manner in 6-year-old beagles (MP) and 14-month-old beagles (YP). Twelve weeks after implantation, the animals were sacrificed and serial sections were prepared. A histometrical analysis was then performed on periodontal regeneration. The MB showed a significantly higher rate (42±19%) of newly formed alveolar bone than the MP (14±8%) (p<0.01), while no difference was observed between the MB and the YB (43±22%). The rate of newly formed cementum in the YB (56±21%) was significantly higher than that in the YP (33±12%) (p<0.05), while no difference was observed between the MB (41±13%) and the MP (28±8%). Our results suggest that middle-aged beagles and young-adult beagles may have an equal potential to augment alveolar bone by the implantation of rhBMP-2/PGS, whereas the potential for cementum augmentation is not as high in middle-aged beagles as it is in young-adult beagles. J Jpn Soc Periodontol, 45: 33-42, 2003.
This study was to investigate the influence of age on the progress of periodontal destruction by examining experimental periodontitis complicated by traumatic lesions. Seventy-two sites in three 1-year-old (group 1y) and 6-year-old (group 6 y) female beagles were used. Both groups 1 y and 6 y were further divided into three groups. In group T, trauma was induced by an orthodontic jiggling force under the appropriate plaque control. In group I, ligature-induced inflammation was provoked. In group TI, both trauma and inflammation were simultaneously induced. The gingival flap was elevated around the experimental teeth, and notches were made on the roots at the height of the crest of the alveolar bone; these notches were used as reference points for histometric measurements. In groups I and TI, a cotton ligature were tied around the neck of the tooth to provoke periodontal inflammation. One week later, a jiggling force was applied in groups T and TI using orthodontic power chains, altering the direction at one-week intervals. The clinical parameters were observed for 17 weeks, followed by histological observation and a histometric analysis. In group T, significant differences were not o bserved between group 1 y and 6 y with regand to clinical and histometric parameters other than tooth mobility. In groups I and TI, group 6 y showed a wider area of inflammation and larger periodontal destruction than group 1y showed. These results suggest that age does not have a significant influence on traumatic lesion, but that periodontal destruction caused by inflammation and/or traumatic force is accelerated in older beagus. J Jpn Soc Periodontol, 45: 43-55, 2003.
We evaluated the utility of three-dimensional computed tomography (3 DCT) for the examination and diagnosis of periodontal disease. Bone resorption or root morphologies affecting the prognosis of periodontal treatment were diagnosed using 3 DCT and conventional intra-oral radiography. The presence of vertical bone defects, bone resorption around the palatal root, furcation involvement, fenestration, enamel projection and root grooves was examined in eight periodontal patients, and the appearances of these factors were verified during flap operations. One-hundred and sixty randomly selected dental radiographies and 160 3 DCT images were presented to twenty dentists. The dentists were divided into three groups according to their experience with periodontal treatment. The presence or absence of the above factors was judged using a 5-rank system. The accuracy of the diagnosis was then evaluated using receiver operation characteristic (ROC) analysis. The results of the 3 DCT examinations were equal or more accurate at identifying all of the examined factors than conventional radiography. Only the vertical bone defect was accurately diagnosed by conventional radiography; fenestration and enamel projection were not diagnosed using the conventional method. Furthermore, the accuracy of the diagnosis for bone resorption around the palatal root of the first molar and furcation involvement depended on the experience of the dentist. Diagnoses based on the 3 DCT images were accurate for all factors except root groove, regardless of dentist experience. The tendency for false positive diagnoses based on conventional radiography increased withperiodontal treatment experience. On the other hand, diagnoses were more accurate when based on 3 DCT images, regardless of dentist experience. These results indicate that 3 DCT greatly facilitates the diagnosis of periodontal disease, regardless of dentist experience, and suggest that 3 DCT images provide useful information for determining appropriate periodontal treatment plans and procedures. J Jpn Soc Periodontol, 45 : 56-66, 2003.
This study evaluated the effects of oral health promotion, focusing on professional tooth cleaning (PTC), in the inhabitants of an isolated island. PTC was performed over a 5-year period on the island of Toshima, which has a population of about 300. Recruited islanders were divided into a test group and a control group, and the effects of PTC were examined by comparing data before and after the activity. The results of the study were as follows: 1) The oral hygiene status improved significantly in both groups; in particular, the improvement in the test group was much higher than that in the control group. 2) A significant improvement in the mean overall probing depth was observed in the test group. In the control group, however, no change in the mean overall probing depth was observed. In addition, significant aggravation was observed in the molar part of the dentition. 3) The number of missing teeth decreased, but a significant difference was not observed. Through practicing PTC regularly for 5 years, the subjects were motivated to maintain good oral hygiene and their periodontal pockets improved. J Jpn Soc Periodontol, 45: 67-73, 2003.
Recent evidence suggests that periodontal status, serum antibody levels for periodontopathic bacteria, and general health conditions are linked. Subjects over the age of 40 years (n=650) were recruited for the present study. Periodontal status was evaluated using the Community Periodontal Index of Treatment Needs (CPITN). The following characteristics, assessed during a general health examination, were used in the analysis: age, gender, body mass index (BMI), systolic and diastolic blood pressure (SBP, DBP), levels of alkaline phosphatase (ALP), total cholesterol (T-CHO), high density lipoprotein cholesterol (HDL-CHO), triglyceride (TG), fasting blood glucose (FBG), c-reactive protein (CRP), white blood cell counts (WBC), platelet counts (PLT) in the peripheral blood, smoking habits, amount of smoking (packsyear), and electro-cardiogram (ECG) rank. The serum IgG antibody titer for Porphyromonas gingivalis fimbriae (IgG. Pg. Fim.), the serum IgG antibody titer for P gingivalis whole cell antigens (IgG. Pg. whole), and the serum IgG antibody titer for Actinobacillus actinomyceterncomitans whole cell antigens (IgG. Aa. whole) were determined in each subject using an enzyme-linked immunosorbent assay. The subjects were divided into 4 different periodontal groups according to their maximum CPITN codes (0/1/2, 3, 4 or missing sextant (MS) subjects). The mean SBP, DBP, TG, WBC, and IgG. Pg. Fim. were significantly higher in the CPITN 4 group than in the CPITN 0/1/2 group. The mean DBP and IgG. Pg. Fim. were significantly higher in the CPITN 4 group than in the CPITN 3 group. Logistic regression analyses performed for 528 subjects (excluding the CPITN MS group) suggested significant associations between CPITN 4 subjects and (males OR: 2.27), smoking habit (OR: 2.36), a high DBP (OR: 1.62), a high WBC (OR: 1.38), a high IgG. Pg. Fim. titer (OR: 1.20), a high IgG. Pg. whole titer (OR: 1.55), and a high IgG. Aa. whole titer (OR: 1.45). These results suggest periodontal status, gender, smoking habits, DBP, WBC, IgG. Pg. Fim., IgG. Pg. whole and IgG. Aa. whole were significantly associated in the population that was examined. J Jpn Soc Periodontol, 45: 74-82, 2003.
The present study investigated the influence of tooth mobility on connective tissue attachment apparatuses. The maxillary second premolars of nine Japanese monkeys were used in the experiment, while the maxillary second molars were employed as the control teeth. Tooth mobility was produced using the method described by Kitamura # (1990). After removing the crowns of the maxillary and mandibular canines, the buccal cusps of the second premolars were intentionally elongated by casting onlays to create bruxism force. The animals were sacrificed after 2, # 4 and 10 weeks. Half of the specify region where the sections were obtained were stained with hematoxylin-eosin with an Indian ink injection, and the other half were observed using immunohistochemistry with anti-von Willebrand Factor antibody and proliferating cell nuclear antigen # (PCNA). A marked difference in the loss of connective tissue attachment was observed, when corresponding regions from the supracrestal connective tissue and the periodontal ligament tissues were compared. In the supracrestal connective tissues, an increase in the number of capillaries in the periodontium, vWF-positive endothelial cells, and PCNA-positive cells in the periphery of blood vessels were evident. Further, no loss of connective tissue attachment was observed. In the periodontal ligament tissues, a decrease in the number of capillaries in the connective tissues, vWF-positive endothelial cells, and PCNA-positive cells in the periphery of blood vessels were observed. A loss of connective tissue attachment was also evident. These results suggest that tooth mobility induces the loss of connective tissue attachment through a loss in tissue vascularity. J Jpn Soc Periodontol, 45: 83-94, 2003.
Comprehensive periodontal treatment, including regenerative therapy and osseointegrated implants, was performed in a patient with aggressive periodontitis. A 36-year-old woman with severe general bone loss and no diagnosable medical disease was referred to our hospital for gingival pain and swelling in bilateral mandibular molar regions. Intraoral findings showed generalized inflamed gingiva and plaque deposits. No other risk factors, other than plaque, were observed in this patient. After initial periodontal therapy, we conducted surgical treatments including regenerative therapies using Enamel matrix derivative (Emdogain), guided tissue regeneration, and osseointegrated implant surgery with guided bone regeneration. After treatment, the patient' s gingival bleeding, plaque score and probing pocket depth improved. The regenerative therapies enabled a gain in attachments, and osseointegrated implants in the right mandibular molar regions improved occlusal function. Esthetic concerns were alleviated by edentulous ridge augmentation with subepithelial connective tissue grafts on the upper anterior regions. These multi-disciplinary treatment modalities was useful for the treatment of patients with aggressive periodontitis. J Jpn Soc Periodontol, 45: 95-104, 2003.
The ability of Lactobacillus salivarius TI 2711 (LS 1) to displace periodontopathic bacteria, like Porphyromonas gingivalis and Prevotella intermedia, was studied using humanvolunteers. LS 1 was one thousandfold more susceptible to lactic acid than Lactobacillus acidophilus, a representative acid-resistant Lactobacillus strain frequently found at the sites of caries, when these bacteria were exposed to 50 mM of lactic acid. In an in vitro system, LS 1 completely killed P. gingivalis within 24 hours when these bacteria were cultured together. In a clinical study, 57 subjects took tablets containing 2×107 CFU or more of LS 1 daily for 4 or 8 weeks. The number of black-pigmented anaerobic rods, which includes most periodontopathic bacteria, in the saliva decreased to one-twentieth of the initial value after 4 weeks, whereas the numbers of whole bacteria, Streptococcus mutans and lactobacilli did not change. While the saliva pH was widely distributed (ranging from 5. 4 to 8. 5) before LS 1 treatment, it converged to within a neutral range of around 7. 3 after treatment. Thus, the possibility that LS 1 accelerates caries formation by lowering the pH in the oral cavity was excluded. These findings suggest that LS 1 may be, potentially useful probiotic agent against periodontopathic bacteria. J Jpn Soc Periodontol, 45 : 105-112, 2003.