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Aggregatibactor actinomycetemcomitans colonizes human periodontal lesions and is implicated in both aggressive periodontitis and chronic periodontitis. Clinical isolated colonies of A. actinomycetemcomitans were rough type. The rough type has a remarkable ability to adhere tenaciously to solid surfaces and colonize firmly. Rough type colonies change into smooth type colonies during the course of repeated inoculation and biofilm-forming activity ceases. Adherence by A. actinomycetemcomitans is mediated by the tight-adherence (tad) gene locus, which includes flp, rcpA and rcpB. In this study, we investigated the relationship between its biofilm-forming ability and expression of the flp, rcpA and rcpB genes associated with fimbriae protein production. First, we changed rough type strain organized biofilm on glass into smooth type and confirmed it by observation of biofilm on glass surfaces. Then, we carried out Real-Time PCR and found that expression of the rcpA and rcpB genes was clearly reduced in smooth type colonies. This suggests that expression of rcpA and rcpB plays a key role in biofilm formation by A. actinomycetemcomitans strains and the establishment of persistent infections in periodontal lesions.

Objectives: Bacterial metabolites demineralize dental hard tissues, and soluble factors lead to tertiary dentinogenesis in the area of the dentin-pulp complex. However, it is unclear whether the oral bacteria are directly involved in the differentiation of dental pulp cells. In this study, we evaluated the effect of oral bacterial extracts on cellular differentiation in human dental pulp-derived cells (hDPC)., Study Design: The hDPC were obtained from third molar teeth, and the cells were subcultured. The sonicated extracts were obtained from Porphyromonas gingivalis (gram-negative) and Streptococcus mutans (gram-positive). The effect of bacterial extracts on cellular growth and differentiation in hDPC were tested., Results: Alkaline phosphatase activity and bone sialoprotein (BSP) gene expression were increased in hDPC exposed to low concentrations of both sonicated extracts, whereas the activity was decreased upon exposure to high concentrations of sonicated extracts from P. gingivalis., Conclusion: This is the first evidence that oral bacteria have a positive effect on cellular differentiation in hPDC., (Copyright 2010 Mosby, Inc. All rights reserved.)

Aggregatibacter actinomycetemcomitans is a pathogen associated with chronic and aggressive periodontitis and extra-oral infections. Fresh isolates of A. actinomycetemcomitans are fimbriated, forming small, rough-phenotype colonies on agar plates and also form biofilms. Recently, it has been reported that amyloid fibers are abundant in natural biofilms, and Escherichia coli and Salmonella spp. produce amyloid fibers that contribute to biofilm formation. This has yet to be reported, however, in A. actinomycetemcomitans. Amyloid binds the Congo red (CR) dye. In this study, therefore, we investigated amyloid formation in A. actinomycetemcomitans using a detection of CR-binding colonies on CR agar plates and CR-binding assay. All rough-phenotype strains formed dark red colonies and smooth-phenotype strains formed white or opaque red colonies on CR agar plates. Compared with smooth-phenotype strains, rough-phenotype strains showed higher CR-binding activity. CR-binding of rough-phenotype strain AKR was not affected by protease digestion or heating, whereas smooth-phenotype strain 29523 showed a marked reduction in CR-binding after both types of treatment. AKR showed amyloid-positive staining with CR to produce yellow green birefringence under polarized light, whereas 29523 showed amyloid-negative staining. These findings indicate that the CR-binding component of rough-phenotype A. actinomycetemcomitans is an amyloid-like fiber.

Galanin (GAL), a 29-amino-acid neuropeptide, is involved in various neuronal functions, including the regulation of food intake, hormone secretion and central cardiovascular regulation. The nucleus tractus solitarius (NTS) is known to plays a major role in the regulation of cardiovascular, respiratory, gustatory, hepatic and swallowing functions. Voltage-dependent Ca2+ channels (VDCCs) serve as crucial mediators of membrane excitability and Ca(2+)-dependent functions such as neurotransmitter release, enzyme activity and gene expression. The purpose of this study was to investigate the effects of GAL on VDCCs currents (ICa) carried by Ba2+ (IBa) in the NTS using patch-clamp recording methods. An application of M617 (GalR1 specific agonist), AR-M961 (GAL receptor GalR 1/2 agonist) and GAL caused inhibition of N- and P/Q-types I(Ba). M617, GAL, and AR-M961 caused inhibition of I(Ba) in a concentration-dependent manner, with IC50s of 678 nM, 325 nM and 573 nM, respectively. This inhibition was relieved, albeit incompletely, by a depolarizing prepulse. Pretreatment with M35 (GalR non-specific antagonist) attenuated the M617-induced inhibition of I(Ba). Intracellular dialysis of the Galpha(i)-protein antibody also attenuated the Gal-induced inhibition of IBa. These results indicate that GAL inhibits N- and P/Q-types VDCCs via Galpha(i)-protein betagamma subunits mediated by GalR1 in NTS.

Silent aspiration of oral microorganisms is a major cause of aspiration pneumonia. To establish oral hygiene criteria for the prevention of aspiration pneumonia in edentulous elderly persons, we investigated the relationship between presence of tongue-coating and number of oral bacteria in saliva and episodes of pneumonia. A total of 71 edentulous Japanese people aged 65 years or older living in nursing homes were enrolled in the study. A tongue plaque index (TPI) was used to evaluate quantity of tongue-coating, with TPI0 signifying no tongue-coating and TPI1 signifying presence of tongue-coating. Edentate elderly with TPI1 demonstrated significantly higher salivary bacterial counts than those with TPI0 (p<0.05). The number of elderly patients developing aspiration pneumonia was larger (p<0.005) in patients with TPI-based poor scores (average TPI>0.5) than in those with TPI-based good scores. The relative risk of developing pneumonia in the good tongue hygiene group compared with in the poor tongue hygiene group was 0.12, 95% confidence interval (CI): 0.02-0.9. The results demonstrate that tongue-coating is associated with number of viable salivary bacterial cells and development of aspiration pneumonia, suggesting that tongue-coating is a risk indicator of aspiration pneumonia in edentate subjects.

Dental pulp has various characteristics in the pulp chamber, but only a few biological evaluations about the effect of age on dental pulp tissue have been reported. The purpose of this study was to compare dental pulp from young and adult rats to characterize the homeostatic mechanism. Dental pulp cells (DPCs) were obtained from the first molar of rats, weighing 150 g each for the young group and 350 g each for the adult group. The expression of core-binding factor alpha-1 (Cbfa-1), vascular endothelial growth factor (VEGF), or heat shock protein (HSP) 27 messenger RNAs (mRNAs) by cultured pulp cells was determined by using a quantitative real-time PCR system after 3, 7, or 14 days. The expression of Cbfa-1 mRNA in the young group was higher than in the adult group. Expression of VEGF and HSP27 mRNAs in the adult group was higher than in the young group. The self-defense system in young DPCs is undertaken by calcification, but in adult DPCs it is carried out by the expression of self-defense proteins and the regeneration of vessels.

Background: In the previous report of the Prognosis and Statistical Investigation Committee of the Japanese Skin Cancer Society, we tabulated data on patients with malignant melanoma who had been registered at major medical institutions (22 institutions on average) in Japan over 5-year periods from 1987 to 1991 (group A) and from 1992 to 1996 (group B). In the present study, patients registered from 1997 to 2001 (group C) were investigated and the data were compared with findings obtained by the subsequent follow-up of groups A and B., Methods: The numbers of melanoma patients registered were: 545 in group A (1987-1991), 699 in group B (1992-1996), and 821 in group C (1997-2001). Because the International Union Against Cancer (UICC) TNM and stage classifications for malignant melanoma were changed substantially in 2002, analyses in the present investigation were performed according to the new classifications. The Kaplan-Meier method was used to draw survival curves, and the log-rank test was used to assess the significance of differences in survival. In addition, the numbers of patients with various kinds of skin malignancies, including not only malignant melanoma but also basal cell carcinoma, squamous cell carcinoma, mycosis fungoides, actinic keratosis, Bowen's disease, and Paget's disease, registered at approximately 100 medical institutions in Japan from 1987 to 2001, were also investigated and data were tabulated., Results: The nationwide survey of Japanese patients with malignant skin tumors from 1987 to 2001 showed that the most prevalent skin tumor was basal cell carcinoma, which increased year by year, followed by squamous cell carcinoma, and then by malignant melanoma. The following results were obtained from the data for melanoma patients registered at major institutions from 1987 to 2001. (1) The overall 10-year survival rates for melanoma patients in each chronological group were ranked as: group C > B > A, although only the difference between groups C and A was statistically significant. (2) The male-to-female ratio ranged from 1: 0.97 to 1: 1.14, and the survival rate of female patients was higher than that of male patients (the 140-month survival rate was 70.6% in females and 60% in males). (3) Assessment of the age distribution showed that the number of patients increased rapidly from ages 40-49 years and reached a peak at around 60 years in all three groups. (4) The sole of the foot was the most common site of melanoma in both males and females, while melanomas on the lower limbs were also prevalent in females. (5) Acral lentiginous melanoma (ALM) was the most common type in all three groups, accounting for nearly 50% of the patients in each group. The number of patients with superficial spreading melanoma (SSM) increased steadily over time and exceeded the number of patients with nodular melanoma (NM) in group C. The prognosis of NM was the worst, while that of SSM was the most favorable. (6) The proportion of stage I patients was larger in group C than in groups A and B, but no significant difference among the groups was observed in the proportions of stage II, III, and IV patients. For patients in stage III, the overall survival rate was higher in group C than that in group A or B, while there was no apparent difference in survival between the groups for patients in stage I or II. For patients in stage IV, the survival rate in group C was slightly lower than that in group A or B. (7) In group C, the overall survival rates for substages III A, B, and C were ranked as III A > III B > III C. (8) The overall survival rates for stage IV M1a, M1b, and M1c were ranked as M1a > M1b > M1c. In group C, the overall survival rate of stage IV patients with a normal serum lactic dehydrogenase (LDH) level was higher than that of patients with elevated LDH values. (9) Evaluation of the effects of some therapeutic procedures (prophylactic lymph node dissection and chemotherapy with and without interferon-beta) on the survivals of patients with melanoma was inconclusive and suggested the need for more studies in this area., Conclusion: In Japan, the number of patients with malignant skin tumors has increased year by year. The prognosis of patients with advanced malignant melanoma remains extremely poor, but that of patients in stage III has shown an improvement.

In order to find informative salivary biomarkers specific to oral cancer we examined expression of 4 kinds of cytokine in saliva. Levels of interleukins (IL-1beta, -6, -8) and osteopontin were measured by ELISA using whole saliva samples collected from 19 patients with oral cancer (9 men, 10 women; mean age, 60.9 years) and 20 healthy persons (15 men, 5 women; mean age, 32 years). Expression of the 4 cytokines was higher in patients with oral cancer than in healthy controls. The difference was significant in IL-6, in particular. The results suggest that saliva offers a potential target for a screening test aimed at detection of precancerous lesions.

The purpose of this study was to evaluate age-related differences in expression of vascular endothelial growth factor (VEGF) by periodontal ligament (PDL) cells. PDL cells were obtained from Wistar male rats weighing approximately 150 g each in the young group and 350 g each in the old group. PDL cells derived from upper and lower incisors were seeded in 35-mm culture dishes after primary culture. For cell proliferation assays, cells were detached and counted at 1, 3, 5, 7, 11 and 14 days after culture. VEGF mRNA expression was analyzed with TaqMan. The number of cells in both groups increased day by day, but the rate of increase in the young group was higher than that in the old group. VEGF mRNA expression in the young group increased from 3 to 14 days, but in the old group increased only slightly over the same time period. Expression ratios in the young group were higher than those in the old group, and there were significant differences between the young and old groups at 7 and 14 days of culture. In conclusion, the data revealed that PDL cells varied with age, and suggest that in view of such changes in cell proliferation and VEGF mRNA expression, age should be taken into consideration in periodontal treatment.

Simvastatin acid (SVA) has been reported to stimulate bone formation by increasing expression of BMP-2 in osteoblasts. Due to their multi-functional characteristics and bioadaptability, cyclodextrins (CDs) are capable of forming inclusion complexes with many drugs by including a whole drug molecule inside their cavity. In the present study, we prepared SVA/CD inclusion complex solutions with different pH values. These were then used to determine their SVA release behavior after coating on titanium substrates, as well as to clarify the characteristics of SVA/CD complexes per se. Results showed that the lower the pH value of the solution, the lower the release kinetics of SVA. Besides, the amount of crystalline complexes in the coatings increased with decrease in pH. These results suggested that the release rate of SVA depended on two factors: pH of the solution and concomitant crystallinity of the coating.

Objectives: Actinobacillus actinomycetemcomitans is a major causative agent of chronic and aggressive periodontitis. Freshly isolated strains of A. actinomycetemcomitans display rough-type colonies and initiate biofilm formation on glass surfaces. The purpose of this study was to determine the antibiotic susceptibility of A. actinomycetemcomitans biofilm during different phases of maturation., Methods: Using 96-well microtitre plates, we determined the antibiotic susceptibility of rough-type strain 310a to concentrations from 0.1 to 10 mg/L each of erythromycin, ofloxacin, ampicillin, cefalexin, tetracycline and minocycline during biofilm formation. Antibiotics were added at the start of the culture (early phase) and after 24 h of cultivation (mature phase)., Results: Adding 10 mg/L of ampicillin, 10 mg/L of cefalexin, 0.1 or 1 mg/L of tetracycline, or 0.1 mg/L of minocycline significantly inhibited 310a biofilm formation in the early phase, but not in the mature phase. Although adding 10 mg/L of erythromycin, tetracycline or minocycline reduced biofilm development in the early phase, it enhanced 310a biofilm development in the mature phase. Ofloxacin exerted a strong inhibitory effect in both the early and mature phases of biofilm formation throughout all experiments., Conclusions: The present study demonstrated that the susceptibility of A. actinomycetemcomitans to many antibiotics decreased after biofilm maturation.

Defensins are known to play an important role in defense against bacteria. It is also known that immunity against infection is compromised with age. The purpose of this study was to evaluate the localization of human beta-defensin (HBD)-2 in human gingival epithelia according to age. Gingival epithelia in maxillary premolar buccal normal regions was immunohistochemically stained for HBD-2. Specimens were divided into two groups: 6 cases in a young group (<20 years old) and 7 cases in an elderly group (>50 years old). Expression of HBD-2 in gingival epithelium in young subjects was mostly detected in the superficial layer of the parakeratinized layer, while some areas of the spinous cell layer in elderly subjects were positive for HBD-2, as was the superficial layer. Two cases in the young group and 5 cases in the elderly group immunoreacted with HBD-2 in the spinous cell layer. Furthermore, immunoreaction was stronger in the elderly group. The results revealed HBD-2 positive cells in spinous cells in the elderly group and in the parakeratinized layer in the young group.

The cutaneous malignancies with an increasing incidence in Japan are squamous cell carcinoma, basal cell carcinoma, and malignant melanoma. As a precancerous state or early lesion, actinic keratoses also deserve attention. According to a nationwide questionnaire survey (responses from 94 centers), basal cell carcinoma has the highest incidence and accounts for nearly 50% of all skin malignancies, followed by squamous cell carcinoma (31%) and malignant melanoma (21%). The number of cases of each tumor has grown annually, and comparison of the percent increases between 1987 and 2001 shows an increase of about 1.5-fold for basal cell carcinoma or 1.7-fold for squamous cell carcinoma or malignant melanoma. Supported by a Grant-in-Aid for Cancer Research from the Ministry of Health, Labor and Welfare, the Malignant Skin Tumor Research Group has been investigating the factors behind these increases by detailed statistical analysis of data obtained from 1987 onwards from designated centers (19-22 centers). Numerous factors have been suggested by this research, but the most important was concluded to be ultraviolet radiation.

Influenza is a major cause of respiratory infection and has a high mortality rate in the elderly. Neuraminidase (NA) on the surface of the influenza virus and bacterial trypsin-like proteases (TLP) play key roles in influenza virus infections. We investigated the effects of oral care on influenza, evaluating in particular the activities of NA and TLP in saliva, as they may contribute to an increased risk of infection with influenza. One hundred ninety elderly patients who visited day care service facilities once a week were randomly assigned to either a professional oral care group or to an own oral care group as the control group. Nine individuals in the control group and one person in the professional oral care group were diagnosed with influenza during the follow-up period. The relative risk of developing influenza while under professional oral care compared to that in the control group was 0.1 (95% CI 0.01-0.81, p=0.008). Significant decreases in numbers of salivary anaerobic bacterial CFUs, and NA and TLP levels were observed in the professional oral care group compared to that in the control group (p<0.01). This study suggests that maintenance of oral hygiene is effective in the prevention of influenza in the elderly.

The purpose of this study was to establish criteria for the visual evaluation of oral hygiene by analyzing the relationship between status of oral hygiene and number of oral bacteria in saliva for use in predicting the development of pneumonia. A total of 145 Japanese people of advanced age living in nursing homes were enrolled in the study. We evaluated the Dental Plaque Index (DPI) and Tongue Plaque Index (TPI) as simple measures of status of oral hygiene. We also determined the number of viable microorganisms in the saliva of each subject. The relationship between the status of oral hygiene and episodes of pneumonia was investigated over a period of one year. Dentate patients with poor oral hygiene as indicated by their DPI and TPI scores demonstrated significantly higher salivary bacterial counts than those with a good score for oral hygiene (p<0.01 and p<0.05, respectively). Both the number of febrile days was significantly higher (p=0.0012), and number of patients developing pneumonia larger (p<0.01) in dentate patients with DPI-based poor scores than those with DPI-based good scores. These results demonstrate a significant positive correlation between salivary bacteria and visual evaluation of oral hygiene in dentate patients according to number of febrile days and development of pneumonia.

Dentilisin is a major surface protease and virulence factor of the bacterium Treponema denticola. In this study, we found that T. denticola reduced inflammatory cytokines, including interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha, in peripheral blood mononuclear cells through degradation by dentilisin.

The purpose of this study was to investigate oral flora in independent persons aged over 80 years with more than 20 remaining teeth. The subjects were 22 participants of the 8020 campaign (6 males and 16 females) with a mean age of 81.3+/-1.6 years and an average of 24.7 teeth (Independent 8020 group). This group was compared with a group of 38 elderly people residing in nursing homes (10 males and 28 females) who had a mean age of 81.3+/-8.5 years and an average of 4.2 teeth (Nursing group with fewer teeth). Saliva samples were collected from the vestibular areas of the maxilla and mandible using cotton swabs. Cell numbers of microorganisms were expressed as colony forming units/ml (CFUs/ml) and compared between the two groups. The average number of Staphylococcus species was 65.2+/-74.4 CFUs/ml in the Independent 8020 group and 400.3+/-352.1 CFUs/ml in the group with fewer teeth (p<0.01); that of Candida albicans was 18.0+/-37.7 CFUs/ml in the Independent 8020 group and 152.9+/-211.9 CFUs/ml in the Nursing group with fewer teeth (p<0.05). Both species showed statistically significant differences between the two groups. This suggests that the Independent 8020 achiever group had better oral hygiene and that the presence of many teeth may be associated with an increased awareness of dental health.

Increasing evidence has linked the anaerobic bacteria forming periodontopathic biofilms with aspiration pneumonia in elderly persons. In experiments designed to eliminate the potent respiratory pathogens forming biofilms in the oral cavity, we have shown that the mechanical and chemical oral cleansing using povidone-iodine effectively reduced the detection rates and numbers of methicillin-sensitive Staphylococcus species, Streptococcus pneumoniae, and Haemophilus influenzae in patients scheduled to undergo oral surgery requiring endotracheal intubation. We confirmed the pathogenicity of periodontopathic anaerobic bacteria for aspiration pneumonia in an experimental mouse model. Based upon the finding of the coexistence of Porphyromonas gingivalis with Treponema denticola in chronic periodontitis lesions, we innoculated a mixed culture of P. gingivalis and T. denticola into the mouse trachea; the resulting infection induced inflammatory cytokine production and caused pneumonia. In another series of investigations, professional oral health care (POHC), mainly cleansing administered by dental hygienists once a week for 24 months to elderly persons requiring daily care, resulted in the reduction of the number of total anaerobes, Candida albicans, and Staphylococcus species and in the number of cases of fatal aspiration pneumonia. We also found that the POHC treatment of elderly persons for 6 months in the winter season reduced the salivary levels of protease, trypsin-like activity, and neuraminidase and also decreased the frequency of influenza cases.

Colonization by periodontopathic bacteria is a risk factor for peri-implantitis. The purpose of this study was to investigate the colonization by black-pigmented anaerobic bacteria that occurs between the time before fixture installation and 6 months after inserting superstructures in implant treatment in partial edentulous cases. Dental plaque was serially collected from around the natural teeth and implants in 12 patients in whom a dental implant was indicated, and Porphyromonas gingivalis and Prevotella intermedia were detected using polymerase chain reaction (PCR). One month after connecting the abutment, the detection rate of P. gingivalis per site from around the implants was 63.7% and that of P. intermedia was 50.8%. Six months after superstructure setting, the detection rate per site of P. gingivalis from around the implants was 56.8% and that of P. intermedia was 41.1%. When chromosomal DNA segmentation patterns in the isolated P. gingivalis and P. intermedia were compared using pulsed field gel electrophoresis (PFGE), the patterns in the natural teeth were in accordance with those in the implants in 3 of 4 cases (75.0%) in P. gingivalis and all cases in P. intermedia. This finding suggested that bacterial colonization around implants occurred early after the implant region was exposed to the intraoral cavity and that the bacteria were transmitted from the area around the natural teeth.

Utilizing PCR, the 16S rRNA detection rates for Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Treponema denticola, and Campylobacter rectus in samples of stenotic coronary artery plaques were determined to be 21.6, 23.3, 5.9, 23.5, and 15.7%, respectively. The detection rates for P. gingivalis and C. rectus correlated with their presence in subgingival plaque.

Adverse skin reactions to anti-tumor agents, can be classified either as general symptoms or as local symptoms. The former type of symptom can manifest as intoxication dermatosis; however, while its occurrence is rare, the symptom that requires the closest attention is toxic epidermal necrolysis, the outcome of which is death in most patients. The latter type of symptom includes extravasation of anti-tumor agents and alopecia. Treatment of extravasation induced skin disorders includes prompt and repeated local injections of steroids, while treatment of alopecia includes scalp cooling and external therapies.

Campylobacter rectus, a gram-negative, microaerophilic, and motile bacterium, has been proposed to play a pathogenic role in human periodontitis. Surface components, such as the flagellum, surface layer (S-layer), and cytotoxin, have been reported as possible virulence factors of the microorganism. In the present study, monoclonal antibodies against surface components of this bacterium were produced to detect and investigate the pathogenic potential of C. rectus in periodontitis. Two monoclonal antibodies, designated CRT-1 and CRT-2, recognized a peculiar 150 kDa S-layer protein by immunoblot analysis. The CRT-2 antibody reacted to all C. rectus strains tested, except for the S-layer negative strain of the species [C. rectus ATCC 33238 S-layer (-) strain]. The CRT-3 antibody reacted to a 60-kDa protein in C. rectus and also cross-reacted with Campylobacter showae ATCC 51164 and CCUG 11641 strains. Using the dot-blot method, we were able to detect C. rectus using the CRT-2 antibody when as few as 103 organisms were present in a subgingival dental plaque sample. Detection of C. rectus in plaque samples correlated significantly with clinical findings such as probing depth (P < 0.001), bleeding on probing (P < 0.001), and gingival index (P < 0.001). These findings indicate that infection by C. rectus may be an important indicator of periodontal disease status.

Purpose: The presence of periodontopathic bacteria is a risk factor for peri-implantitis. The present study examined colonization by periodontopathic bacteria and their transmission from periodontal pockets to osseointegrated implant sulcus., Materials and Methods: Plaque samples were collected from 105 sites in the 15 patients who participated in the study. Colonization by these bacteria was examined by polymerase chain reaction (PCR) and culture. The transmission of periodontopathic bacteria from periodontal sites of natural teeth to the implant sulcus was analyzed by pulsed field gel electrophoresis (PFGE)., Results: The PCR detection rates of Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, and Treponema denticola were 80.0%, 53.3%, 46.7%, 60.0% and 40.0%, respectively. Colonizations by P gingivalis and A actinomycetemcomitans were statistically correlated with periodontal pockets and implant sulcus regions (P < .01). The PFGE patterns of the P gingivalis strains isolated from each patient were identical, but differed from those from other patients. The PFGE patterns of P intermedia strains were identical in 2 out of 3 patients., Discussion: These analyses indicated that there appeared to be transmission of P gingivalis and P intermedia from the periodontal pocket to the peri-implant region., Conclusion: Elimination of these periodontal pathogens from the patient's oral cavity before administering dental implant treatment may inhibit colonization by these pathogens and reduce the risk of peri-implantitis.