Effects of fixed orthodontic appliances on subgingival microflora

Abstract: Objectives: Fixed orthodontic appliances cause plaque accumulation around bands and brackets. Since the microbiological composition of dental plaque is closely connected to periodontal tissue health, the aim of this study was to determine the effects of fixed orthodontic appliances on subgingival microflora and periodontal status. Methods: This prospective study was carried out on 32 adolescents scheduled for fixed orthodontic treatment. Subgingival dental plaque samples and periodontal records (pocket probing depth and clinical attachment level) were obtained in four recording times: before bonding of fixed appliances (T0), 1 (T1), 3 (T2) and 6 (T3) months after the beginning of orthodontic therapy, in order to detect the changes in periodontopathic anaerobe microbial flora and its effects on periodontal status. Results: The values of pocket probing depth, total number of microorganisms and number of patients with positive findings of Prevotella intermedia and other periodontopathic anaerobes increased from T0 to the maximum obtained in T2 recording time. Both clinical and microbiological values decreased 6 months after the beginning of orthodontic therapy. Conclusions: The therapy with fixed appliances may transitionally increase the growth of periodontopathogenic bacteria and consequently result in gingival inflammatory response but without destructive effect on deep periodontal tissues.     

Identification of periodontopathic bacteria DNA from periodontitis-involved gingival tissue using a PCR method

The purpose of this study was to determine the presence of periodontopathic bacteria DNA in the granulation tissue of periodontally involved gingival tissue. Forty periodontitis patients were examined. Subgingival plaque and saliva samples were collected from the patients before surgery. Then, granulation tissue was also collected during surgery. Another 20 patients, who had more than 4 mm in probing pocket depth, were also examined as a control. They received only initial treatment without periodontal surgery. Plaque and saliva samples were also collected from them. Seven periodontopathic bacteria, Porphyromonas gingivalis, Bacteroides forsythus, Toreponema denticola, Campylobacter rectus, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Prevotella nigrescens, were detected by a PCR method from these samples of all patients. As clinical parameters, probing pocket depth, clinical attachment level, and bleeding on probing were recorded. One year after surgery, sampling of subgingival plaque and saliva, and measurement of clinical parameters were performed on the patients. The DNA of periodontopathic bacteria was detected in the granulation tissue of 29 out of 40 patients. P. gingivalis, B. forsythus, T. denticola, C. rectus, A. actinomycetemcomitans, P. intermedia and P. nigrescens were detected in 23, 11, 12, 9, 3, 2 and 1 subject(s) respectively. The sites with undetectable level of any periodontal pathogens at one year after surgery showed a clinical attachment gain of 2.44 mm, while those that showed detectable pathogen levels had only a 0.77 mm gain. Our results indicated that the removal of granulation tissue contributed to eliminating periodontal pathogens and to avoiding re-infection by those bacteria. Complete eradication of periodontopathic bacteria would be necessary for successful periodontal treatment.     

Comparative analysis of putative periodontopathic bacteria by multiplex polymerase chain reaction

Background and Objective:  The polymerase chain reaction (PCR) has been applied for the rapid and specific detection of periodontopathic bacteria in subgingival plaque and is potentially of clinical benefit in the diagnosis and treatment of periodontitis subjects. However, several technical points need to be modified before the conventional PCR detection system can be used by clinicians.
Material and Methods:  To develop a PCR-based technique more applicable for clinical use than conventional PCR, we established a multiplex PCR for five putative periodontopathic ( Treponema denticola , Porphyromonas gingivalis , Aggregatibacter actinomycetemcomitans , Prevotella intermedia and Tannerella forsythia ) and two nonperiodontopathic ( Streptococcus sanguinis and Streptococcus salivarius ) species of bacteria using whole-plaque suspension as templates, and detected bacteria in subgingival plaque taken from 85 subjects at the supportive periodontal therapy stage after active periodontal treatments.
Results:  Among putative periodontopathic bacteria, the detection frequency of T. denticola and P. gingivalis was elevated in parallel with higher probing pocket depth and clinical attachment loss, and had 4.2–14.1 times increasing odds of the clinical parameters tested. Detection of any of the five species of putative periodontopathic bacteria markedly increased the odds ratio of a higher probing pocket depth, clinical attachment loss and bleeding on probing.
Conclusion:  The multiplex PCR system developed in this study enabled the detection of all the bacteria under investigation in one reaction tube in a less time- and labor-intensive manner than conventional PCR. These results support the potential clinical use of multiplex PCR for detecting periodontopathic bacteria and for evaluating therapeutic strategies and predicting the prognosis for each subject.     

Topical application of the controlled release strips containing ofloxacin (PT-01) in periodontal therapy

The association of periodontopathic bacteria in the subgingival plaque with human periodontal disease has been well established. However, past attempts at reducing the level of pathogenic bacteria by using antibiotics as well as other antibacterial substance, so far, have not been fully successful. In this study, the effect of topical application of ofloxacin (OFLX), a synthetic antibiotic, was evaluated in relation to the clinical parameters. For this purpose, the new developed controlled release strips containing OFLX (PT-01), in which there were structurally immediate- and sustained-releasing portions, were used. 147 adult patients suffering from moderate to severe periodontitis were selected for this study. The patients had received no periodontal treatment previously and had taken no antibiotics within the preceding 6 months. Three different sites with a deep probing pocket depth (greater than or equal to 5 mm) were randomly selected in each patient, and were divided into three groups, i.e., PT-01 applied site (T), placebo-applied site (P) and control site (C). Periodontal treatments consisted of oral hygiene instruction and supragingival scaling on day 0 and 7, and subgingival scaling and root planing on day 14. PT-01 was applied in the periodontal pocket weekly on day 0 to 35, and clinical parameters on each site were recorded weekly. The results showed that, during first 14 days, significant reduction in the percentage of the sites which showed bleeding on probing, pus discharge or mobility of the tooth was observed in the PT-01 applied site. However in placebo and/or control group, no significant change in any parameters was observed in this period. While, after subgingival scaling and root planing, significant improvement was found at all sites in every clinical parameter. Especially, PT-01 applied sites showed significant improvement in the gingival index and bleeding on probing, compared to placebo-applied or control sites. These results suggest that weekly insertion of PT-01 in the periodontal pocket along with the subgingival scaling and root planing could have significant effect on the improvements in the gingival inflammation. Taken together, weekly application of PT-01 might have ameliorating effect as adjuncts of mechanical subgingival plaque control in the periodontal treatment.     

The in vivo expression of membrane-bound CD14 in periodontal health and disease

BACKGROUND: Membrane-bound CD14 (mCD14) is a myeloid differentiation antigen expressed on monocytes/macrophages and neutrophils. It is a key molecule responsible for the innate recognition of bacteria by host cells and functions as an important receptor for bacterial lipopolysaccharide. This study investigated the in vivo expression profile and levels of mCD14 in healthy and diseased gingival tissues. METHODS: Gingival biopsies were obtained from 24 patients with chronic periodontitis, including 22 periodontal pocket tissues, 13 clinically healthy tissues, and 18 inflamed connective tissues (i.e., granulation tissues). Gingival biopsies from seven periodontally healthy subjects were used as controls. mCD14 was detected by immunohistochemistry. RESULTS: mCD14 was detected in 21 of 22 periodontal pocket tissues and all other categories of tissues. The mCD14-positive cells were mainly confined to the gingival epithelium-connective tissue interface. The expression levels in periodontally healthy subjects were significantly higher than in the patients. Within the patients, clinically healthy tissues showed greater levels of mCD14 than periodontal pocket tissues and granulation tissues. CONCLUSIONS: mCD14 was commonly expressed in both healthy and diseased gingival tissues and was predominantly confined to the epithelium-connective tissue interface. The positive relationship observed between mCD14 expression levels and periodontal health may imply that mCD14 is associated with favorable host responses to bacterial challenge and contributes to maintaining periodontal homeostasis.     

Azithromycin in periodontal treatment: more than an antibiotic

Azithromycin is a macrolide antibiotic used extensively in medicine for the treatment of a wide range of infections such as upper respiratory tract infections, middle ear infections, sexually transmitted infections and trachoma. It is also effective against the most common periodontopathogens. The versatility of the macrolides extends beyond their antibiotic properties as a result of their well-documented immune-modulating/anti-inflammatory effects. Macrolides, including azithromycin, are therefore used to treat diseases not associated with bacteria, such as severe asthma, chronic obstructive pulmonary diseases and, more recently, cystic fibrosis. Azithromycin is concentrated in neutrophils, macrophages and particularly fibroblasts; all of these cells are central players in the pathogenesis of most periodontal diseases. This paper reviews the diverse properties of azithromycin and the clinical periodontal studies of its effects in both the treatment of periodontitis and in resolving drug-related gingival overgrowth. Evidence exists to support the use of a single course of azithromycin in the treatment of advanced periodontal diseases. Azithromycin could have a triple role in the treatment and resolution of periodontal diseases: suppressing periodontopathogens, anti-inflammatory activity and healing through persistence at low levels in macrophages and fibroblasts in periodontal tissues, even after a single course of three tablets. If future periodontal research confirms these properties, it could become a valuable host-modulator in periodontal treatment.     

Periodontal healing and bone regeneration in response to azithromycin

Azithromycin, first synthesized in 1980, is a macrolide antibiotic related to erythromycin. It is widely used by the medical profession as a broad‐spectrum antibiotic in the treatment of pneumonia, urinary tract infections and tonsillitis. In addition to its antibiotic properties, azithromycin has immune‐modulating effects and is used for this reason in the management of cystic fibrosis and chronic obstructive pulmonary diseases. The drug is taken up by neutrophils, macrophages and fibroblasts, and is slowly released by these cells. Three diverse case reports are presented in which a single course of azithromycin (consisting of one 500 mg tablet being taken a day for three days) was prescribed before any periodontal intervention occurred. Azithromycin was the principal mode of treatment of severe chronic and aggressive periodontitis in Cases 1 and 2. Azithromycin, together with monthly subgingival debridement, was the treatment in Case 3 (severe chronic periodontitis in a poorly controlled diabetic complicated by gingival overgrowth related to medication with a calcium channel blocker). Favourable resolution of inflammation, reduction in pocket depths and evidence of bone regeneration were evident, even when no periodontal treatment had occurred. In Case 3, resolution of gingival overgrowth occurred over eight months. The potential implications for periodontal management, understanding of the pathogenesis of periodontal diseases and periodontal research are briefly discussed.     

Real-time polymerase chain reaction quantification of human cytomegalovirus and Epstein-Barr virus in periodontal pockets and the adjacent gingiva of periodontitis lesions

BACKGROUND: Genomic sequences of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV), two herpesviruses, can frequently be detected in periodontal pockets of progressive periodontitis lesions, but the prevalence and load of the two viruses in gingival tissue are unknown. This study determined levels of HCMV and EBV DNA in the periodontal pocket and in the adjacent gingiva of periodontitis lesions using a real-time polymerase chain reaction (PCR) assay. MATERIAL AND METHODS: A total of 20 systemically healthy periodontitis patients participated in the study. Nine patients below 35 years of age were tentatively diagnosed as having aggressive (early onset) periodontitis, and 11 patients 36-56 years of age as having chronic (adult) periodontitis. Clinical parameters were evaluated using established methods. Using periodontal curettes, specimens were harvested from 6-10 mm periodontal pockets and from the adjacent inflamed periodontal pocket wall. A 5'-nuclease (TaqMan) real-time PCR assay was used to identify and quantify genomic copies of periodontal HCMV and EBV. RESULTS: HCMV DNA was detected in 78% of subgingival and 33% of gingival tissue samples from aggressive periodontitis lesions, but only in 46% of subgingival and 9% of gingival tissue samples from chronic periodontitis lesions. In aggressive periodontitis, HCMV subgingival and gingival tissue counts were positively correlated with periodontal pocket depth and probing attachment loss at sample sites (p6 mm, but none of 14 patients having mean pocket depth at sample teeth相似文献   

A double-blind placebo-controlled trial of azithromycin as an adjunct to non-surgical treatment of periodontitis in adults: clinical results

BACKGROUND/AIMS: The aim of the study was to investigate the clinical and microbiological effects of azithromycin as an adjunct to the non-surgical treatment of periodontitis in adults. Azithromycin is an antibiotic which is taken up by phagocytes and is released over long periods in inflamed tissue but requires a total of only three doses of 500 mg to produce its therapeutic effect. METHOD: 46 patients were treated in a double-blind placebo-controlled study with assessments at weeks 0, 1, 2, 3, 6, 10 and 22. Throughout the trial measurements were made of plaque, gingival bleeding, calculus, probing pocket depths and bleeding on probing. Microbiological sampling was carried out from a selected pocket >or=6 mm at each visit. The regime employed consisted of OHI, scaling and root planing at weeks 0, 1 and 2 with reinforcement of OHI and minimal scaling at weeks 6, 10 and 22. Patients were randomly assigned to receive either azithromycin, (A), or placebo capsules, (C), 500 mg, 1x daily for 3 days at week 2. 44 patients completed the study. Mean pocket depths were analysed using analysis of covariance in 3 groups with initial pocket depth values of 1-3 mm, 4-5 mm and >or=6 mm. RESULTS: The results of the microbiology have been reported in a separate paper. The clinical data showed that by week 22 a lower % of pockets initially >5 mm deep remained above that level in the 23 patients taking azithromycin (A), than the 21 taking the placebo (C), (A, 5.6%; C, 23.3%). Also at week 22, for pockets initially 4 mm or more, the test group had fewer pockets >3 mm deep (A, 26.1%; C, 44.3%), fewer failing to improve in probing depth (A, 6.6%; C, 21.6%) and fewer continuing to bleed on probing (A, 46.9%; C, 55.6%) when compared with the control group. Pocket depths initially 4-5 mm or 6-9 mm analysed by analysis of covariance showed lower mean pocket depths in the patients on azithromycin, at weeks 6, 10 and 22, (pockets initially 4-5 mm, p<0.001 on all occasions, pockets initially 6-9 mm, p<0.001, week 6; p< 0.003, week 10; p<0.001, week 22). CONCLUSIONS: Azithromycin may be a useful adjunct in the treatment of adult periodontitis, particularly where deep pockets are present.     

Periodontal probing: What does it mean?

Abstract The periodontal probe has been and continues to be used as an important diagnostic instrument by the dental profession. The measurements recorded with the probe have generally been considered to represent a reasonably accurate estimate of sulcus or pocket depth. Recent reports on the histopathology of the periodontal lesion and the histological features of a healing lesion, together with histological studies on the relationship of the probe to periodontal tissues, have shed some new light on periodontal probing. It is now apparent that probing depth measured from the gingival margin seldom corresponds to sulcus or pocket depth. The discrepancy is least in the absence of inflammatory changes and increases with increasing degrees of inflammation. In the presence of periodontitis the probe tip passes through the inflamed tissues to stop at the level of the most coronal intact dento-gingival fibers, approximately 0.3–0.5 mm apical to the apical termination of the junctional epithelium. Decreased probing depth measurements following periodontal therapy may be due in part to decreased penetrability of the gingival tissues by the probe. Following treatment aimed at obtaining new attachment in periodontal defects, wider variations may occur between the location of the probe tip and the most coronal dento-gingival fibers than in the case of untreated sites. This is due in part to the formation of a so-called “long” junctional epithelium. In the absence of inflammation this epithelium may not be penetrable during ordinary probing, but could account for a rapid increase in probing depth measurements when inflammatory changes allow the probe to traverse the epithelium and/or the adjacent infiltrated connective tissue. In view of the difficulty inherent in relating periodontal probing measurements to actual sulcus or pocket depth, the interpretation of periodontal probing in the practice of periodontics may need reappraisal.     

Azithromycin as an Adjunctive Treatment of Generalized Severe Chronic Periodontitis: Clinical,Microbiologic, and Biochemical Parameters

Background: This study examines the efficacy of azithromycin in combination with non‐surgical periodontal therapy on clinical and microbiologic parameters and gingival crevicular fluid (GCF) matrix metalloproteinases‐8 (MMP‐8) levels over 6 months in patients with severe generalized chronic periodontitis (CP). Methods: Twenty‐eight of 36 patients with severe generalized CP were included in this randomized, double‐masked, placebo‐controlled, parallel‐arm study. They were randomly assigned to azithromycin or placebo groups (500 mg, once daily for 3 days). Probing depth (PD), clinical attachment level, dichotomous presence or absence of supragingival plaque accumulation, and bleeding on probing were recorded. GCF samples were obtained from one single‐rooted tooth with PD ≥ 6 mm, whereas microbiologic samples were collected from two single‐rooted teeth with PD ≥ 6 mm. Microbiologic parameters were analyzed by quantitative real‐time polymerase chain reaction for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia, and total bacteria. GCF MMP‐8 levels were determined by immunofluorescence assay. Results: Azithromycin and placebo groups demonstrated similar but significant improvements in all clinical parameters (P <0.05). A. actinomycetemcomitans, P. gingivalis, T. forsythia, P. intermedia, and total bacteria significantly decreased over the 6‐month period in both groups, whereas F. nucleatum was significantly reduced in all visits in the azithromycin group, with the levels also being lower compared with those of the placebo group (P <0.05). The azithromycin and placebo groups exhibited significant reduction in GCF MMP‐8 levels at the post‐treatment visit and at 2 weeks (P <0.05). Conclusion: On the basis of the present findings, it can be concluded that adjunctive azithromycin provides no additional benefit over non‐surgical periodontal treatment on parameters investigated in patients with severe generalized CP.     

The herpesvirus-Porphyromonas gingivalis-periodontitis axis

OBJECTIVES AND BACKGROUND: Members of the herpesvirus family have accumulated considerable support for a role in severe types of periodontitis. This study aimed to examine whether human cytomegalovirus (HCMV), Epstein-Barr virus type 1 (EBV-1) or herpes simplex virus (HSV) together with the major periodontopathic bacterium Porphyromonas gingivalis might interact in the pathogenesis of periodontal breakdown. METHODS: Sixteen subjects each contributed paper point samples from two progressing and two stable periodontitis lesions, as determined by ongoing loss of probing attachment. Polymerase chain reaction methodology was used to identify subgingival herpesviruses, P. gingivalis and other bacterial pathogens. Chi-squared tests and multivariate logistic regression were employed to identify statistical associations between herpesviruses, periodontopathic bacteria and clinical variables. RESULTS: HCMV and HSV were both significant predictors of the presence of subgingival P. gingivalis. In turn, P. gingivalis was positively associated with periodontitis active disease, probing attachment level, probing pocket depth, gingival bleeding upon probing and patient age. EBV-1 was not linked to P. gingivalis, although the virus was predictive of periodontitis active disease. The periodontitis disease risk associated with herpesvirus-P. gingivalis combinations depended on both site-specific and subject-specific factors. CONCLUSION: The present data of aggressive periodontitis implicate HCMV, HSV and P. gingivalis as either cofactors in its etiology or triggers of relapses. Further studies are needed to determine the spectrum of periodontopathogenicity of herpesviruses and effective management of these viruses in periodontal sites.     

Periodontal considerations of implants and implant associated microbiota

The scientific and clinical acceptance of the success of osseointegrated dental implants has been firmly established, but the relationships between clinical observation and periimplant pathogenesis is not well understood. Data and concepts regarding the diagnostic value of traditional periodontal evaluation parameters, such as pocket probing depth, bleeding on probing, attachment loss, gingival and plaque indices, and the amount of attached gingiva are discussed. The microbiologic characterization of plaque associated with various implant systems reveals many similarities and some differences compared to natural teeth. An hypothesis for the "periodontal" etiology of implant failure is proposed. The maintenance of edentulous and partially edentulous patients with implants is discussed.     

In situ detection of matrix metalloproteinase-9 (MMP-9) in gingival epithelium in human periodontal disease

BACKGROUND AND OBJECTIVE: As the periodontal lesion develops, the junctional epithelium migrates apically in conjunction with the dissolution of the most coronal Sharpey's fibers. Because matrix metalloproteinase-9 (MMP-9) has been identified in migrating epithelial cells and invading tumors, we propose that this enzyme is produced by gingival keratinocytes in advanced periodontal lesions. METHODS: To test this idea, biopsies of inflamed gingival tissues were obtained from patients with advanced periodontitis. Healthy gingival tissue samples were utilized as controls. The presence and activity of MMP-9 was evaluated by combining indirect immunofluorescence of gingival tissue samples and gelatin zymography of gingival epithelium separated from connective tissue. RESULTS AND CONCLUSIONS: The staining pattern showed the presence of MMP-9 in junctional and pocket gingival epithelial cells, polymorphonuclear neutrophils (PMNs) and as a scattered deposit along connective tissues of periodontitis-affected gingival tissues. Gelatin zymography permitted the identification of pro-MMP-9 in surcular/pocket epithelium derived from inflamed gingival tissues. Lower levels of MMP-9 were detected in epithelium not exposed to inflammation. These observations suggest a role for MMP-9 in gingival epithelial response to periodontal infection.     

牙周洁治对人牙周炎袋底微生物和龈沟液量的影响

目的:探讨牙周洁治对人牙周炎袋底微生物和龈沟液量的影响,为研究牙周洁治机制提供依据。方法:选60例牙周炎患者,随机分为2组,每组30例,洁治组作牙周洁治,对照组用常规漱口液漱口,分别在治疗前、治疗后1周和治疗后1月用刚果红负性染色法观察袋底微生物的变化,并测定牙周探诊深度(PD)、龈指数(GI)和龈沟液量(GCF)的变化。结果:洁治组在洁治后1周时牙周袋底的球菌比率明显增加,杆菌和螺旋体比率及PD和GCF明显降低;对照组GI轻度降低,但PD和GCF以及袋底的球菌、杆菌、螺旋体比率无明显变化;洁治组和对照组的球菌、杆菌和螺旋体比率及PD、GI和GCF均有显著性差异。洁治后1月时PD、GI和GCF量及袋底的微生物比率与洁治1周时无显著性差异。结论:牙周洁治对人牙周炎袋底微生物有明显的改善作用,可通过减少袋底致病菌比率和降低PD以减轻牙周炎症和减少龈沟液的分泌。     

Langerhans' cell histiocytosis in a 5-year-old girl: evidence of periodontal pathogens

BACKGROUND: Langerhans' cell histiocytosis (LCH) is a rare disorder characterized by Langerhans' cell proliferation in various organs or tissues. When periodontal tissue is involved, clinical manifestations can vary from gingival recession and pocket formation to severe alveolar bone loss. This case report describes periodontal pathogens found in the pockets of involved primary teeth. METHODS: A 5-year-old girl with LCH presented with loose teeth. Intraoral examination and radiographs revealed deep pockets and severe bone loss around all primary molars. Bacterial samples were obtained from saliva and subgingival plaque and analyzed for the presence of five periodontopathic bacteria using a polymerase chain reaction (PCR) method. Due to severe periodontal destruction, all primary molars were extracted, and a gingival biopsy was taken from tooth T to confirm the diagnosis of LCH. RESULTS: The biopsy specimen revealed the histologic features of LCH. The patient was diagnosed as having periodontitis as a manifestation of LCH. PCR results of subgingival plaque from LCH-affected molars indicated the presence of Porphyromonas gingivalis, Tannerella forsythensis, Treponema denticola, and Prevotella intermedia. However, Actinobacillus actinomycetemcomitans was absent from these teeth. No tested bacteria were found in the non-affected anterior teeth. CONCLUSIONS: The bacteria commonly associated with periodontal disease were detected in subgingival plaque samples from this LCH patient. More microbiological data are required to understand the role of these bacteria in LCH-associated periodontal destruction.     

Clinical application of tetracycline-containing strips (LSD) in periodontal disease

The purpose of this study was to evaluate the clinical application of strips containing 10% Tetracycline (TC) in periodontal disease. In this double blind study, placebo strips, which did not contain TC, were also prepared. Ninety-two sites in 46 cases with greater than a 4 mm periodontal pocket were randomly assigned to experimental and control study groups. The following clinical parameters at each site were recorded at Weeks 0, 1, 2 and 3 after insertion of the LSD or placebo strip: plaque and calculus score, probing depth, gingival inflammation (redness, swelling, bleeding on probing, pus discharge), mobility of the tooth, pain on insertion of strip and pain after the procedure. The residual quantity of TC in the periodontal pocket was also determined at 1, 2 and 7 days after inserting the LSD. All clinical data was evaluated using 3 types of statistical test (X2 test, Mann-Whitney's U test and Wilcoxon's test). Thus, the following results were obtained: 1. The LSD group showed much improvement in clinical condition compared with the placebo group. 2. The conditions of bleeding, redness or swelling of gingival tissue were much improved in the LSD group, even after data evaluation with all 3 types of statistical test. 3. The residual quantity of TC was decreased day by day until finally it was not recognized in the 7 day samples. 4. This study suggested that the application of LSD in the periodontal pocket could be effective in periodontal treatment.