[in Japanese]

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Sulfated glycosaminoglycan in gingival crevicular fluid is favored as a biomarker of possible boneresorption. Despite common use of filter paper to collect gingival crevicular fluid, little attention has been paid to the role of the type of filter paper, despite it being a critical factor in determining fluid uptake and migration. We assessed in vitro paper suitability and its subsequent quantification of sulfated glycosaminoglycans. Samples of fluid containing chondroitin 4-sulfate wcrc collected on diffcrcnt paper strips. After sampling, strips were stained directly with 0.2% alcian blue solution containing 0.05 M MgCl2, 0.4 M guanidine-HCl, 0.02 M sulfuric acid, and 0.25% Triton X-100 at pH 1.5, and analyzed them using a chromatoscanner. The cellulose acetate membrane (Separax (R)) strip was found to be the most suitable for recovering chondroitin 4-sulfate in fluid. It was superior in staining of chondroitin 4-sulfate, fluid adsorption, and background destaining. Our in vitro study suggests that sampling time was less than 60 seconds and fluid volume collected by Separax (R) paper strips was 3 microliters. J Jpn Soc Periodontol, 44: 117-130, 2002.

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We studied parameters for measuring periodontal disease activity using gingival crevicular fluid (GCF). We evaluated prostaglandin E₂ (PGE₂) and cyclooxygenase 2 (COX 2) mRNA detected in GCF, and compared these with clinical parameters.
GCF was taken from 40 periodontal regions of the molar teeth in 20 adult periodontal patients, 20 samples were from a probing depth (PD) exceeding 7mm and 20 from a PD of less than 3mm in each patient. Before and 1 month after initial treatment, we measured PD, clinical attachment level (CAL), bleeding on probing (BOP) and plaque index (PlI) PD exceeding 7mm was defined as seriously diseased and PD of less than 3mm PD was defined as mildly diseased. One month after initial treatment, GCF was taken agein from the same sites. PGE₂ in GCF was measured using enzyme linked immunosorbent assay (ELISA), and COX 2 mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR).
After initial treatment, PD changed from 7.2±0.5mm (mean±SD) to 3.6±1.1mm in the seriously diseased and from 2.7±0.6mm to 2.1±0.6mm in the mildly diseased. CAL changed from 8.0±1.1mm to 5.2±1.4mm in the seriously diseased and from 3.5±0.8mm to 2.9±0.9mm in the mildly diseased. In the serious diseased, PGE₂ in GCF improved from 450±340pg/site to 112±70pg/site, and in the mildly diseased, from 170±200 pg/site to 70±68pg/site. PGE₂ correlated with PD and CAL, but COX 2 mRNA expression showed no correlation with PGE₂. These results suggest that PGE₂ in GCF is effective in determining periodontal disease activity, and the effectiveness of initial preparation can be evaluated under 200pg of PGE₂ per site. J Jpn Soc Periodontol, 44: 131-147, 2002.

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We studied tooth displacement effected by root planing (RP) in an experimental periodontitis. Subjects were 8 beagles. A resin cap was set on the mandibular 3 rd premolar (P3), pretreated with pulpotomy, and a bridge splint was set on the mandibular 2 nd and 4 th premolars to measure vertical extrusion. To prevent effects from cheek and tongue pressure, a removable cheek-and-tongue guard was set around both of sides of the lower P3 except during measuroment. Inflammation group: Experimental periodontitis around the left P3 was induced by dental floss ligature for 12 weeks in 4 beagles. RP group: Experimental periodontitis around the left P3 was induced by dental floss ligature for 4 weeks, then RP under local anesthesia at the fourth and fifth weeks in 4 beagles. Teeth were cleaned 3 times a week for the 8 remaining weeks. Control group (healthyinflammation and RP sides) : Periodontal tissues of the right P3 were maintained by tooth cleaning for 12 weeks. Tooth displacement was determined once a week by measuring the distance from a silicone rubber impression. Clinical parameters: Probing pocket depth PPD), probing attachment level (PAL), tooth mobility (TM), and gingival crevicular fluid (GCF) were also measured.
Results were asfollows:
1. In the inflammation and RP groups, vertical extrusion increased pregularay.
2. In the RP group, vertical extrusion PAL, and TM appeared to increase promptly after RP and decreased to a steady phase 2 weeks later.
3. PPD and GCF appeared to decrease promptly after RP.
Our results suggest that vertical extrusion is effected by inflammatory condition and RP. J Jpn Soc Periodontol, 44: 148-158, 2002.

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In the time of the post sequence, attention has been increasingly focused on risk factors of 'common disease', caused by genetic and environmental factors. The oral environment and host immune response cause periodontitis and its progression, necessitating a better understanding of the genetic relationship to periodontitis. We studied relative factors of periodontitis with single nucleotide polymorphisms (SNPs) analysis. SNPs are the most common form of DNA sequence variation and their analysis covers many genes.
Subjects were 13 early-onset (aggressive) periodontitis patients, 9 adult (chronic) periodontitis patients, and 19 healthy controls. We studied the association of 59 single nucleotide polymorphisms (SNPs) in candidate genes of periodontitis, such as interleukin 1 (IL 1) and tumor necrosis factor α (TNFα), with periodontitis using the TaqMan polymerase chain reactions. SNPs were selected based on linkage disequilibrium.
Significant differences were seen in the frequency (p<0.05) in genotypes on cathepsin G (CTSG) and TNF receptor-associated factor 1 (TRAF 1) between early-onset periodontitis patients and controls. Significant differences were also detected in the frequency in genotypes on interleukin 10 receptor β (IL 10 RB) and matrix metalloproteinase 9 (MMP 9) between adult periodontitis patients and controls. A further significant difference was seen in the frequency in genotypes on interferon γ (IFNG) between earlyonset and adult periodontitis patients.
These results suggest an association of SNPs on CTSG and TRAF 1 in early-onset periodontitis and on IL 10 RB and MMP 9 in adult periodontitis and a difference of SNPs on IFNG in early-onset and adult periodontitis.
Further studies of SNPs registered in a Japanese SNPs database of JSNP, would thus clarify genetic risk factors in periodontitis. J Jpn Soc Periodontol, 44: 159-167, 2002.

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To identify factors associated with “morning breath” (physiological breath odor preceding breakfast) in healthy adults, we assessed breath odor, analyzed intraoral factors, and collected saliva and tongue coat samples incubated to ascertain the relationship between intraoral bacteria and breath odor. Subjects were 44 healthy men with a mean age of 24.1 years. The breath odor of each was assessed by an organoleptic test and quantified using a portable sulphide monitor (Halimeter RH-17 E®) and gas chromatography. Results were as follows: Breath odor was organoleptically detectable in all subjects. When subjects were categorized based on organoleptic tests, a significant difference was seen in Halimeter values and concentrations of 3 volatile sulphide compounds (VSCs). A significant correlation was seen between organoleptic measurement and Halimeter values or VSC concentration. Among VSC concentrations, the correlation was highest between total VSC and hydrogen sulphide levels. Tougue coat scores and turbidity tended to increase with the organoleptic score. Higher tongue coat scores tended to be associated with greater turbidity.
An increase in odor score coincided with a significant in counts for total bacteria, aerobic bacteria, streptococci, and anaerobic bacteria in the tongue coat. No significant differences in bacteria counts were seen, however, in saliva. Significant correlations existed between tongue coat score/turbidity and counts for total bacteria, aerobic bacteria, streptococci, and anaerobic bacteria in the tongue coat.
Our findings suggest 3 broad conclusions: the tongue coat is the major contributor toward morning breath ; halitosis severity depends on the total number of bacteria in the tongue coat; and hydrogen sulphide is the primary component of halitosis. J Jpn Soc Periodontol, 44: 168-177, 2002.

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We determined the prevalence of adult periodontal disease using the Community Periodontal Index of Treatment Needs (CPITN) conducted at the health promotion center in Agematsu-cho, Kiso, Japan.
Subject were 292 adults 104 men with a mean age of 61.2 years and 188 women with a mean age of 52.2 ears. Subjects were stratified by 10-year groups-20-39, 40-49, 50-59, 60-69 and 70 years. Dental examination involved counting intact treated, and untreated teeth and teeth requiring prosthetic appliances. We examined the correlation between the number of teeth and gender or age group and CPITN using Student's t test. We also studied the correlation between CPITN of each tooth versus gender or age group using the chi-square test. Oral hygiene was assessed and the oral hygiene score compared by gender and age the using chi-square test.
The numbers of present, intact, and treated teeth were not correlate with age. The number of present teeth in subjects over 60 years old group was significantly lower than in 20-39 year age group (p<0.01). CPITN score was higher with age in women (p<0.01) but not man. The number of subjects having poor oral hygiene increased with age (p <0.01).
Our results suggest that women over 60 years old require regular treatment for dental caries. All adult subjects in Agematsu should be treated for periodontal disease and instructed in oral hygiene. J Jpn Soc Periodontol 44: 178-187, 2002.

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We evaluated the efficacy of guided tissue regeneration (GTR) in generalized chronic periodontitis. GTR using multiple membranes for a series of bone defects is applicable provided that no more than 2 bone defects are involved. Therefore, multiple membranes technique to place several membranes on series of bone defects and vestibularplasty utilizing muco-gingival split flap to maintain the new regenerated tissue optimally were developed. We evaluated clinical parameters before and 1 year after in 35 teeth of 13 patients having a probing pocket depth (PPD) exceeding 6 mm and the clinical attachment level (CAL). Preoperative PPD was 7.3±1.7 mm and CAL 8.4±2.1 mm. Postoperative PPD 1 year after treatment was 2.0±0.8 mm and CAL 3.7±1.6 mm. The sufficient attachment gain was reveal as 4.7±1.8 mm (p< 0.05).
Compared to GTR applied to a single tooth, we observed almost the same attachment gain. Combining multiple membranes technique and vestibularplasty using a mucogingival split flap has appears useful in regenerating the periodontal tissue and treating generalized chronic periodontitis. J Jpn Soc Periodontol, 44: 188-198, 2002.

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We evaluated the clinical efficacy of a machine with voice input for examining probing depth (PD) and tooth mobility (TM). Subjects were 4 men and 6 women averaging 24.5 ± 0.7 years of age who had normal dentition and 28 intact teeth with a normal periodontium. Examinations were conducted by 2 dentists-1 with 14 years of clinical experience (Dr-A), and 1 with 1 year (Dr-B) and 3 dental hygienists-1 with 18 years of clinical experience (DH-a), 1 with 7 years (DH-b) and 1 with 4 years (DH-c). We used a machine with voice input (Perionavigation system® : Perionavi (GC Co.)) and a pocket probe (PCPUNC 15, Hu-Friedy Co.). PD was measured at 6 points-esial, central and distal points on facial, palatal and lingual sides. and TM was measured by Miller's classification. We divided subjects into 3 groups: Perionavi use, no Perionavi use and no assistant, and an assistant but no Perionavi use. Statistically analysis was conducted 2-way ANOVA between the 3 groups and 5 dentists/hygienists for the measurement time. For PD, a statistically significant difference (p<0.01) was seen between Dr-A and all DH, Dr-B and all DH, DH-a and DH-c, and DH-b and DH-c. For TM, a statistically significant difference (p<0.01) was seen between Dr-A and all DH, Dr-B and DH-b, between all DH, and DH-c and DH-b. A statistically significant differences (p<0.001) was seen between the 3 groups for PD and TM. In the no Perionavi use/no assistant and assistant/no Perionavi use groups, the difference in clinical experience did not influence PD time. The Perionavi group did not show this trend. In the assistant/no Perionavi use group, the difference in clinical experience influenced TM time measurement, but not in the other 2 groups.
A machine with voice input thus appears useful in clinical application. J Jpn Soc Periodontol, 44: 199-205, 2002.

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Long-term generalized chronic periodontitis often causes overbite with excessively elongated lower incisors. In such cases, healthy lower molars are usually chosen for orthodontic anchorage to intrude lower incisors. Reciprocal force loading produced by incisal intrusion on molars with loss of supporting alveolar bone is detrimental, however, even if periodontal treatment eliminates inflammation. We describe a case in which titanium screws were implanted in the cortical bone of the chin as intramaxillary anchorage, resulting in succesful intrusion of the elongated lower incisors, 5 mm at the edge, resulting in a proper occlusal relationship and esthetic improvement of the lower face. J Jpn Soc Periodontol, 44: 206-212, 2002.

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We studied the effect of mastic chewing gum as an antiplaque agent. Subjects were 20 systemically and periodontally healthy volunteers. The effects of mastic gum were assessed from 2 double-blind, randomized crossover, studies. In the first trial, after mechanical tooth brushing, 4-treatment crossover was used to compare bacterial growth in saliva following the use of mastic or placebo gum and mouth rinse using 0.004% benzethonium chloride or phosphate-buffered saline (PBS). Saliva samples were collected after mouth rinsing, then diluted, inoculated onto 10% horse chocolate blood agar plates, and cultured anerobically at 37.. for 48 hours. The total number of bacterial colonies on each plate was then calculated. In the second trial, the effects of mastic gum on de novo plaque accumulation on tooth surfaces and gingival inflammation were evaluated through 7 days without mechanical oral hygiene following random use of either mastic or placebo gum. The degree of plaque accumulation and gingival inflammation were compared between groups (n=10). The total number of bacterial colonies was significantly reduced by 4 hours of chewing mastic gum compared to the number obtained with placebo gum or PBS mouth rinse (p<0.05, Student's t test). The effect of this gum was similar to that of mouth rinse with benzethonium chloride. The mastic group showed significantly reduced plaque indices (2.69±0.29 vs 3.15±0.24, p=0.001, Student' s t test) and gingival indices (0.44±0.15 vs 0.66±0.23, p=0.02) compared to the placebo group. These results suggest that mastic chewing gum is an useful antiplaque agent in part through reducing bacterial growth in saliva and pla que formation on teeth. J Jpn Soc Periodontol, 44: 213-219, 2002.

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