The main purpose of this investigation was to compare the healing process and the type of soft tissue attachment after periodontal surgery in two conditions of root surfaces exposed by bone removal.
In this investigation, four healthy adult monkeys were used. Before surgical phase, healthy periodontium was established by professional cleaning three times a week for a month.
Full thickness gingival flaps were raised and buccal alveolar bone plates were removed by dental chisel within an area extending 2mm mesio-distally, 3mm vertically.
In forty-three exposed root surfaces, residual periodontal fibers and root cementum were preserved, and in forty surfaces, they were removed by root planing.
Two, four, eight and twelve weeks after surgery, the monkeys were killed and examined histometrically.
The results were as follows:
1) In the fiber preserving group, epithelial downgrowth could not be observed 2, 4, 8 or 12 weeks after surgery. But in the fiber removal group, apparent epithelial downgrowth was observed from 4, 8 and 12 weeks, in spite of little gingival inflammation. Twelve weeks after sugery, the difference between them was about 0.5mm on the average.
2) In the fiber preserving group, functionally oriented connective tissue reattachment was observed in proportion of about 70 pecent in the range of measurement from 2 to 12 weeks.
It was considered due to the effect of fiber splicing.
But in the fiber removal group of 2 and 4 weeks materials, much more parallel collagen adhesion to root surfaces was observed. In 8 and 12 weeks after surgery, functionally oriented fibrous attachment increased as a formation of new cementum.
3) The results of statistical analyses revealed that the amount of functionally oriented connective tissue reattachment is correlated to residual periodontal fiber 2 and 4 weeks after surgery, but 8 and 12 weeks, correlated to the amount of new cementum formation.
4) A side-result obtained from this investigation was the tendency that epithelial downgrowth occured along smooth root surfaces, rarely on rough root surfaces.

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Only fragmentary knowledge is available concerning the morphology of subgingival plaque formation. The purpose of this study is to observe the sequential development of bacterial plaque on subgingival area by scanning electron microscopy.
Eight teeth in seven patients during treatment for chronic periodontitis were used in this study. These teeth with severe periodontal lesion, probeable to a depth of 6mm or more, would have to be extracted for periodontal reasons. A metal inlay into which dentin fragment had been inserted was fastened with temporary cement in a cavity prepared from gingival margin to subgingivally about 5mm. In order to observe plaque formation under the same conditions, a thorough root planing was carried out every time an inlay was set and the subjects were instructed to avoid as much as possible cleaning the tooth during the experimental periods. In this way, this inlay remained over and over in the same cavity for varying periods (from 1 day to 49 days). Forty specimens from eight teeth were observed by SEM.
The results were as follows;
1. The most apical border of subgingival plaque was distinguished from the dentin surface or the acquired pellicle. Until 21 days, the distance from the gingival margin to it was gradually increased, but afterwards its value was not changed.
2. The rate of plaque advance into subgingival area was in proportion to the amount of supragingival plaque particularly in early plaque development.
3. The leukocytes which seemed to be derived from periodontal pocket wall were predominantly observed on an area being 2-3mm from gingival margin. It was likely that leukocytes might have played an important role in host defense against plaque invasion.
4. As to the process of subgingival plaque formation, after supragingival plaque had been allowed to accumulate, subgingival plaque formation occurred. Namely, it seemed that the establishment of subgingival plaque followed the occurrence of apical growth into the pocket from supragingival plaque.
The experiment suggested that the formation of subgingival plaque is a slow process as compared with that of the supragingival plaque, and even after 49 days, the bacterial plaque invaded only one third of the pocket depth. It seemed that the subgingival plaque had to be formed under the constant exposure of host's defense mechanisms, for example, PMNLs.

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The present investigation was to examine whether pathologic changes in the dental pulp may be induced by advancing perodontitis or not.
Thirteen periodontally diseased teeth as experimental group and 5 teeth with clinically healthy periodontium as contol group were used in this study. The extracted teeth were pre-fixed, demineralized, post-fixed and embedded in Epon 812. The serial transverse sections of 1μm thickness prepared were stained with toluidine blue and obseved for microscopic findings.
The results were as follows;
1) Of 13 experimental teeth, the histologically healthy pulp in 6 teeth, the hyperemia in 2 teeth, the inflammatory change in one tooth, chronic pulpitis in one tooth and necrosis in 3 teeth were found.
2) The pulp of periodontally advanced teeth with deep pocket in 10mm and 100% bone loss showed the pathological lesions in many cases.
3) Bacterial invasion into the pulp via apical foramen would cause a pulp necrosis.

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Correlation between the serum antibody titer against the seven species of oral anaerobic bacteria and various clinical findings of 31 periodontal patients was studied. As periodontal parameters, Gingival Index, Plaque Index, periodontal pocket depth, gingival crevicular fluid flow and alveolar bone loss were measured, and then peripheral venous blood of the patients was collected.
Seven species of anaerobic periodontopathic bacteria—Bacteroides gingivalis, Bacteroides melaninogenicus subsp. intermedius, Bacteroides melaninogenicus subsp. melaninogenicus, Fusobacterium nucleatum, Actinobacil lus actinomycetemcomitans, Eikenella corrodens and Capnocytophaga species were used in this study. Serum antibody titer against the sonicated antigen from these microorganisms was determined using an ELISA.
A close correlation between the serum antibody titer against B. gingivalis and the degree of periodontal destruction was found. Statistically, periodontal pocket depth and alveolar bone loss were significantly correlated with the antibody titer. There was no significant relation between the parameters and the antibody titer against the other six species of bacteria.
These findings suggest that the measurement of the serum antibody titer against B. gingivalis is useful as a diagnostic measure for screening the periodontal disease.

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The purpose of this experiment was to evaluate the endogenous and succinate respiration in the canine normal gingiva and the healing gingiva following flap operation using the Oxygen Electrode technique.
The operation was performed under general anesthesia on the left mandibular canine, premolar and molar gingiva, using the right side as a control. Samples of the gingiva were excised and minced with a razor blade on the 3rd, 7th, 14th, 21st, 28th and 35th day following the operation. The respiration of the mined gingiva was measured.
Experimental results were as follows:
1) The endogenous respiration was measured with the Oxygen Electrode technique on gingiva samples weighing from 5 to 70mgs. The most stable respiration was found in the groups of gingival tissue weighing 20 to 40mgs.
2) The mean value for endogenous respiration of normal gingiva was 0.85±0.29 microliters of oxygen consumption per dry weight tissue per hour.
3) When endogenous respiration was stimulated, there was a graded response to the addition of succinate.
A respiratory stimulation of 1.5 times the endogenous rate was obtained by the addition of 5mM succinate and 20mM succinate stimulated the endogenous respiratory rate by 3.7 fold. No singnificant changes were observed in succinate respiration following the addition of more than 50mM succinate.
4) The endogenous respiration was elevated on the 3rd and 7th postoperative day. There was decline in the respiration to approximately the level of normal gingiva from 21st to 35th day.

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The assessment of the inflammatory condition of the periodontium was evaluated to measure the hemoglobin in saliva by ortho-tolidine method and the relationship between the amount of salivary occult blood and the bleeding index was investigated.
It was found that the amount of salivary occult blood closely related to the bleeding index.
Subjects were 92 patients. 41 patients (mean age 35.3y) were patients visiting the Department of Endodontics and Periodontics, 51 patients (mean age 19.4y) were hospitalized-patients at Nishitaga National Hospital.
The results were follows:
A significant correlation was observed between the bleeding index and the amount of salivary occult blood. Patients who suffered from cerebral paralysis had higher bleeding index than the others.
It is concluded that the measurement of salivary occult blood is useful to assess the inflammatory condition of the periodontium.

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This clinical study was conducted to evaluate the effect of application of chlorhexidine (CH) paste using an applicator on periodontal disease. Forty patients with inflamed gingiva at least at frontal teeth were divided into 4 groups: (A) Applied 0.05% CH paste using an applicator, (B) Applied 0.05% CH paste with a finger, (C) Applied placebo paste using an applicator, and (D) Applied placebo paste with a finger. The application of each paste was conducted by a double blind method and the patients were indicated to apply the paste once a day for 2 weeks and also instructed to apply the paste into the gingival pocket and between teeth of frontal segments. Clinical assessment of periodontal conditions were performed at the initial and at each end of trial week according to the criteria mentioned in the method.
The results obtained were as follows;
(i) In all 4 groups, the reductions of the plaque score and the pocket depth compared initial values with those at 2nd week were highly significant (p<0.001).
(ii) Similar significant reductions (p<0.01) of the mean gingival scores were revealed in all 4 groups.
(iii) These reductions were significantly greater in group A than in the other groups, and the least in group D.
(iv) The average redness scores were significantly greater (p<0.05) in group C than in group B.
(v) The reductions of the swelling were significantly greater (p<0.001) in group B than in group C during the 1st week, but no significant differences were seen between group B and group C after 2 weeks.
(vi) No remarkable side effect of the use of chlorhexidine was observed for the period.
From those results, it might be mentioned that periodontal disease can be well controlled by application of 0.05% chlorhexidine paste using the applicator as an adjunct to daily toothbrushing.

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This study investigated the effects of 1-Hydroxyethane-1, 1-diphosphonate (EHDP) on the mineralization of early dental plaque.
Twenty adults (10 males and 10 females) with no systemic disease volunteered in this study. The subjects were divided into 2 groups, and either of a 1 percent EHDP or a placebo was given as a rinsing solution 3 times daily for 5-day experimental period. This study was carried out according to a double blind with cross over experimental design. The 5-day old plaque was harvested from the maxillary incisors, and calcium, phosphate, nitrogen and Ca/N ratio were determined on a dry weight basis.
Rinsing with EHDP solution significantly reduced both plaque Ca content and Ca/N ratio than with placebo solution (p<0.05). The inhibitory effect of EHDP on the mineralization of plaque was more pronounced in subjects who revealed heavy Ca deposition in placebo periods. It was concluded from these results that EHDP would be an effective agent in preventing the dental calculus in vivo.

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The effects of periodontal initial preparation included orthodontic treatment were researched. The changes of the width of keratinized and attached gingiva, and the gain of the attachment level were observed.
The subjects were one male and two females having periodontal disease with malalignment. Fore areas of three anterior teeth were reseached. They were treated with periodontal initial preparation and orthodontic treatment.
The results were as follow.
1) The keratinized and attached gingiva appeared as a result of orthodontic treatment and initial preparation.
2) The widths of keratinized gingiva and attached gingiva increasing after treatment were enough to maintain the health of the gingiva.
3) The gain of the attachment level on the exposed root surfaces were observed.

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The purpose of this study was to assess of the value of including repetition and reinforcement in a plaque control program for 42 patients with periodontal disease, 21 to 63 years of age.
They received audio-visual motivation (color slides-sound tape and video-tape) combined with individual toothbrushing lesson in the Bass technique on the initial visit and also received three additional visits for repetition and reinforcement of the instructions plus interdental cleaning. Their visits were conducted at intervals of one week. The audio-visual program, edited by our own Department, lasted for 20 minutes and comprised a popular review of the etiology, the development and the main symtoms of periodontitis, followed by a short introduction to the method of brushing and interdental cleaning. Our goal in teaching oral hygiene procedures is to reduce plaque accumulations until they are found on 20% of the available toothsurfaces in the expression of O'Leary Plaque Score.
It was concluded that the repetition and reinforcement components of this plaque control program were of significant value improving the oral hygiene performance of the periodontally diseased patients.

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The purpose of this investigation was to study the relation between the area of root surfaces and the level of existing periodontal supporting tissues when affected with periodontal disease, especially with furcation involvement. 83 teeth (the upper first and second molar, the lower first and second molar) were used for this study. The root of each tooth was separated into three parts which consist of the root trunk except the furcation area, the furcation area and the divisional roots. On the upper molar the divisional roots were the palatal root, the bucco-mesial root and the bucco-distal root and on the lower molar they were the mesial root and distal root. The surface area of each separated part was measured by the modified membrane technique (vinyl-acetate coating method).
The results were as follows.
1) The surface area of the divisional root
The range of the means of the surface area in the divisional roots was 79.5mm² to 159.4mm². The surface area of the lower first molar mesial root was the largest, the upper second molar bucco-distal root, the smallest. On the upper first molar, the palatal root was significantly larger than the other roots.
2) The surface area of the furcation
The range of the means of the surface area was 11.4mm² to 15.1mm². No significant difference was found among all the surface areas of the furcations.
3) The proportion of the surface area of the divisional roots to the total root surface (root trunk+divisional roots)
The proportion was the largest in the lower first molar of all the molars.
It may be necessary to base on the results of this study in periodontal examination, diagnosis and treatment.

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Plaque disclosing soloutions were applied to the teeth for revealing the dental plaque and evaluating the efficiency of tooth brush. It is generally recognized that dental plaque plays a major role in etiology of periodontal disease.
An effective plaque control must be parts of the treatment plan for every dental patient, for this, disclosing solution is helpful for patient's plaque control. So we made investigation with a view to compare of the effects of various disclosants on plaque accumulation.
Prior to the start of the experiment, all students had their teeth scaled and polished by doctor, and then, two pieces of experimental tooth slices with8×8mm in width and length which were made by the central anterior teeth, were put on the buccal surface of the upper first molar with Coe-pak.
After 6 days, we removed the experimental slices, and then, we stained the student's different teeth and examined into several items. On the other hand, experimental slices were stained by different disclosing solution and investigated the color difference of the experimental slices with DENTAL COLOR ANALYZER (NAKAGAWA K. K.)
So we obtained the result throughout our experiment, MT-750, MT-1000 and neutral red had good scores.

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Covering operative defects in the oral cavity is often necessary. During the past few years, lyophilized porcine skin (L. P. S.) have been used. Recently lyophilized porcine dermis (L. P. D.) is used in our clinic.
By using of lyophilized porcine dermis (L. P. D.) for buccal frenectomy, a good clinical healing process was observed.
Lyophilized porcine dermis (L. P. D.) has exceedingly permeability as compared with lyophilized porcine skin (L. P. S.)
It is easy to return from the freeze-dried state by soaking in the saline solution and does not need to distinguish the surface from reverse side on the occasion its use.
Considering the necessity of a second operation for mucosal grafts, lyophilized porcine dermis (L. P. D.) can be used successfully in buccal frenectomy.

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The effective dose and safety of zomepirac were evaluated in a double-blind controlled study, using mefenamic acid as a control drug, in the treatment of pain after minor surgical procedures of after tooth extraction in the field of dentistry.
One hundred and nine patients were included in the statistical analyses. The results obtained were as follows.
1) No difference was found in any patient demographic parameter among the drug treatment groups included in evaluation of drug efficacy.
2) In respect to the analgesic efficacy after the first dose, the zomepirac sodium a 100mg group (here-after referred to as Z 100 group) was significantly superior to the zomepirac sodium 50mg group (hereafter referred to as Z 50 group), and the mefenamic acid group (hereafer referred to as M group) tended to be superior to the Z 50 group.
3) The Z 100 group tended to be superior to the M group at 30 minutes after treatment in pain intensity and pain intensity difference.
4) The time of onset of analgesic action did not differ significantly among the drug treatment groups. However, the duration of action tended to be longer in the Z 100 group than in the Z 50 group.
5) Patient's impression tended to be rated better in the Z 100 group than in the Z 50 group. However, evaluation by the doctor in charge showed no significant difference among the drug treatment groups.
6) No significant difference was found in the incidence of side effects, safety evaluation or utility evaluation among the drug treatment groups.
From the above, it was indicated that in analgesic efficacy, zomepirac 100mg was significantly superior to zomepirac 50mg and equal to or superior to mefenamic acid and that in safety, the three drug groups are almost equal.

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