Adjunctive effects of systemic amoxicillin and metronidazole with scaling and root planing: a randomized, placebo controlled clinical trial.

J Contemp Dent Pract. 2007;8(5):51-9

Authors: Moeintaghavi A, Talebi-ardakani MR, Haerian-ardakani A, Zandi H, Taghipour S, Fallahzadeh H, Pakzad A, Fahami N

AIMS: The objective of this study was to investigate the effect of the systemic administration of metronidazole and amoxicillin as an adjunct to initial periodontal therapy in patients with moderate to severe chronic periodontitis. METHODS AND MATERIALS: This randomized, double blind, placebo controlled parallel study involved 50 adult patients with untreated periodontitis who were randomly assigned to receive either a full-mouth scaling and root planing along with systemic metronidazole and amoxicillin (T group) or scaling and root planing with a placebo (P group). Clinical measurements including probing depth (PD), clinical attachment levels (CAL), Plaque Index (PI), and Bleeding Index (BI) were recorded at baseline and six to eight weeks after therapy. The deepest pocket was selected and samples for microbiological testing were taken. Patients received coded study medications of either 500 mg amoxicillin in combination with 250 mg metronidazole or an identical placebo every eight hours for seven days following scaling and root planing. RESULTS: There was a significant change in PD (P=0.0001), CAL (P=0.00001), PI (P<0.05), and BI (P<0.05) in the T group compared to the placebo group after therapy. Parallel to the clinical changes, treatment significantly reduced the number of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and P. intermedia (Pi) compared with baseline in the T group (P=0.003, 0.021 and 0.0001, respectively). However, in the P group only the Pi colony count was reduced significantly (P=0.0001). After therapy, there was a significant difference between the T and P groups in the number of patients negative for Aa, Pg, and Pi (Pv = 0.033). CONCLUSIONS: The significant differences between treatment and placebo groups are in line with other studies and support the considerable adjunctive benefits of the combination of amoxicillin and metronidazole in the treatment of chronic periodontitis.

PMID: 17618330 [PubMed - indexed for MEDLINE]

Multiparameter assessments to determine the effects of sugars and antimicrobials on a polymicrobial oral biofilm.

Appl Environ Microbiol. 2006 Oct;72(10):6734-42

Authors: Yang Y, Sreenivasan PK, Subramanyam R, Cummins D

Clinical studies indicate relationships between dental plaque, a naturally formed biofilm, and oral diseases. The crucial role of nonmicrobial biofilm constituents in maintaining biofilm structure and biofilm-specific attributes, such as resistance to shear and viscoelasticity, is increasingly recognized. Concurrent analyses of the diverse nonmicrobial biofilm components for multiparameter assessments formed the focus of this investigation. Comparable numbers of Actinomyces viscosus, Streptococcus sanguinis, Streptococcus mutans, Neisseria subflava, and Actinobacillus actinomycetemcomitans cells were seeded into multiple wells of 96-well polystyrene plates for biofilm formation. Quantitative fluorescence and confocal laser scanning microscopy (CLSM) examined the influences of dietary sugars, incubation conditions, ingredients in oral hygiene formulations, and antibiotics on biofilm components. Biofilm extracellular polymeric substances (EPS) were examined with an optimized mixture of fluorescent lectins, with biofilm proteins, lipids, and nucleic acids detected with specific fluorescent stains. Anaerobic incubation of biofilms resulted in significantly more biofilm EPS and extractable carbohydrates than those formed under aerobic conditions (P < 0.05). Sucrose significantly enhanced biofilm EPS in comparison to fructose, galactose, glucose, and lactose (P < 0.05). CLSM demonstrated thicker biofilms under sucrose-replete conditions, along with significant increases in biofilm EPS, proteins, lipids, and nucleic acids, than under conditions of sucrose deficiency (P < 0.05). Agents in oral hygiene formulations (chlorhexidine, ethanol, and sodium lauryl sulfate), a mucolytic agent (N-acetyl-L-cysteine), and antibiotics with different modes of action (amoxicillin, doxycycline, erythromycin, metronidazole, and vancomycin) inhibited biofilm components (P < 0.05). Multiparameter analysis indicated a dose-dependent inhibition of biofilm EPS and protein by chlorhexidine and sodium lauryl sulfate, along with distinctive inhibitory patterns for subinhibitory concentrations of antibiotics. Collectively, these results highlight multiparameter assessments as a broad platform for simultaneous assessment of diverse biofilm components.

PMID: 17021225 [PubMed - indexed for MEDLINE]

Antibiotic susceptibility of the bacteria causing odontogenic infections.

Med Oral Patol Oral Cir Bucal. 2006 Jan;11(1):E70-5

Authors: Bresc&#xF3;-Salinas M, Costa-Riu N, Berini-Aytés L, Gay-Escoda C

AIMS: An evaluation is made of bacterial species and susceptibility to various antibiotics used in application to odontogenic infections of periapical location and in pericoronitis of the lower third molar, with the aim of optimizing the antibiotherapy of such infections and thus preventing unnecessary side effects and over-treatment. MATERIAL AND METHODS: Sixty-four patients with odontogenic infection were selected on the basis of a series of inclusion and exclusion criteria. Samples were collected from lesions under maximally aseptic conditions, avoiding oral saprophytic contamination. The samples were cultured and incubated under aerobic and anaerobic conditions, followed by bacteriological identification and antibiotic susceptibility testing. RESULTS: A total of 184 bacterial strains were isolated and identified, comprising grampositive facultative anaerobes (68%), gramnegative strict anaerobes (30%) and grampositive facultative anaerobes (2%). Regardless of the origin of the odontogenic infection, the causal bacteria yielded the best results in terms of increased sensitivity and lesser resistance with amoxicillin / clavulanate and amoxicillin, respectively (p<0.05). DISCUSSION: There are increasingly numerous reports in the literature of growing bacterial resistance to antibiotics in infectious processes affecting non-buccodental territories. This same tendency has not been observed in relation to oral infections, though important resistance has been documented for certain concrete antibiotics. According to our results, the common-use antibiotics with the greatest sensitivity and lowest resistance were shown to be amoxicillin/clavulanate followed by amoxicillin alone.

PMID: 16388299 [PubMed - indexed for MEDLINE]

Cerebral infarctions and brain abscess due to Lemierre syndrome.

Intern Med. 2005 Jun;44(6):653-6

Authors: Shibasaki Warabi Y, Yoshikawa H, Idezuka J, Yamazaki M, Onishi Y

Lemierre syndrome is characterized by anaerobic bacterial infection in the head and neck, causing thrombophlebitis of the jugular vein and septic metastasis to various distant organs, most often the lungs. Here we describe previously unreported clinical features of cerebral infarctions and brain abscess due to metastatic septic embolism of this uncommon but lethal syndrome, and the successful course of treatment with ampicillin, cefotaxime and metronidazole.

PMID: 16020900 [PubMed - indexed for MEDLINE]

Periodontal diseases as bacterial infection.

Med Oral Patol Oral Cir Bucal. 2004;9 Suppl:101-7; 92-100

Authors: Bascones-Mart&#xED;nez A, Figuero-Ruiz E

The periodontal disease is conformed by a group of illnesses affecting the gums and dental support structures. They are caused by certain bacteria found in the bacterial plaque. These bacteria are essential to the onset of illness; however, there are predisposing factors in both the host and the microorganisms that will have an effect on the pathogenesis of the illness. Periodontopathogenic bacterial microbiota is needed, but by itself, it is not enough to cause the illness, requiring the presence of a susceptible host. These diseases have been classified as gingivitis, when limited to the gums, and periodontitis, when they spread to deeper tissues. Classification of periodontal disease has varied over the years. The one used in this work was approved at the International Workshop for a Classification of Periodontal Diseases and Conditions, held in 1999. This study is an overview of the different periodontal disease syndromes. Later, the systematic use of antibiotic treatment consisting of amoxicillin, amoxicillin-clavulanic acid, and metronidazole as first line coadjuvant treatment of these illnesses will be reviewed.

PMID: 15580140 [PubMed - indexed for MEDLINE]

Periodontal diseases: microbiological considerations.

Med Oral Patol Oral Cir Bucal. 2004;9 Suppl:82-91; 75-82

Authors: Liébana J, Castillo AM, Alvarez M

The location of plaque-associated gingivitis at the gingival portion of the tooth plays an essential role in its genesis. However, at times local and other host response modifying factors also have an influence. The pathogeny of periodontitis is more complex. The microorganisms that comprise subgingival plaque are capable of acting directly on periodontal tissues or of modifying the host response, whereas the participation of the plaque per se (normal, decreased, or increased) is as decisive as the action of the bacteria themselves in the emergence of the disease. Different types of periodontitis are associated with specific microorganisms. The most periodontopathogenic are A. actinomycetemcomitans, P. gingivalis, and T. forsythensis. Periodontitis as a whole, represent the source of complications such as root caries, endoperiodontal processes and periodontal abscesses. They are associated with various illnesses such as atherosclerosis, diabetes, and respiratory infections, amongst others, as well as pathological oral halitosis. The different modalities of PCR are particularly important in the microbiological diagnosis of periodontitis, although on the negative side of things, it must be pointed out that in vitro sensitivity studies cannot be performed using this technique. First line antibiotic treatment of periodontitis includes amoxicillin/ clavulanic acid, metronidazole (associated or not with amoxicillin) and clindamycin.

PMID: 15580139 [PubMed - indexed for MEDLINE]

Treatment options in odontogenic infection.

Med Oral Patol Oral Cir Bucal. 2004;9 Suppl:25-31; 19-24

Authors: Maestre-Vera JR

Most infections of the oral cavity are primary, odontogenic infections, with dental caries, gingivitis, and periodontitis the most common. Treating these infections will encompass odontologic, antimicrobial, surgical or combined treatment. Antimicrobial treatment includes the use of betalactams, macrolydes, tetracyclins, metronidazole, clindamycin, or combined treatment. The most commonly used ones are administered orally. PK/ PD parameters predict THE clinical and microbiological efficacy of the antibiotic. The three indices that are generally used to measure clinical efficacy are: T >MIC (time during which the concentration is above the minimum inhibitory concentration), Cmax/ MIC (ratio between peak concentration and the minimum inhibitory concentration) and AUC/ MIC (ratio between the area under the curve and the minimum inhibitory concentration). Amoxicillin/ clavulanic acid is one of the antibiotics recommended for the treatment of odontogenic infections due to its wide spectrum, low incidence of resistance, pharmacokinetic profile, tolerance and dosage.

PMID: 15580134 [PubMed - indexed for MEDLINE]

Antimicrobial susceptibility of bifidobacteria.

J Antimicrob Chemother. 2005 Jan;55(1):38-44

Authors: Moubareck C, Gavini F, Vaugien L, Butel MJ, Doucet-Populaire F

OBJECTIVES: The aim of our study was to analyse the antibiotic susceptibility of various strains of Bifidobacterium spp. to a wide range of antimicrobial agents. METHODS: Fifty strains belonging to eight species of bifidobacteria, isolated from humans, animals or probiotic products, were tested for susceptibility to 30 antibiotics by disc diffusion on Brucella agar supplemented with 5% laked sheep blood and vitamin K1 (1 mg/L). MICs of nine anti-anaerobe agents, including three new molecules (telithromycin, linezolid and gatifloxacin), were determined using the reference agar-dilution method. RESULTS: All strains of bifidobacteria, whatever the species, were sensitive to penicillins: penicillin G, amoxicillin (MIC(50) 0.06 mg/L), piperacillin, ticarcillin, imipenem and usually anti-Gram-positive antibiotics (macrolides, clindamycin, pristinamycin, vancomycin and teicoplanin). Susceptibility to cefalothin and cefotetan was variable. Most isolates (70%) were resistant to fusidic acid. As expected, high resistance rates were observed for aminoglycosides. Metronidazole, an agent known for its anti-anaerobe activity, was ineffective against 38% of the strains. The newly commercialized molecules, telithromycin, linezolid and gatifloxacin, were active with MIC(50)S of 1 mg/L. The only variation in susceptibility observed among the different species concerned Bifidobacterium breve, which appeared to be generally more resistant. Potentially acquired resistance was only observed against tetracycline and minocycline, in 14% of the strains. CONCLUSIONS: With regard to a general concern about the safety of probiotics, such as potential transferability of resistance determinants, bifidobacteria, with their low natural and acquired resistance to 30 antibiotics, appear risk-free.

PMID: 15574479 [PubMed - indexed for MEDLINE]

Effectiveness of antimicrobial adjuncts to scaling and root-planing therapy for periodontitis.

Evid Rep Technol Assess (Summ). 2004 Jan;(88):1-4

Authors: Bonito AJ, Lohr KN, Lux L, Sutton S, Jackman A, Whitener L, Evensen C

PMID: 15164672 [PubMed - indexed for MEDLINE]

Brain abscess due to Gemella haemolysans.

J Clin Microbiol. 2004 May;42(5):2338-40

Authors: Lee MR, Lee SO, Kim SY, Yang SM, Seo YH, Cho YK

We present a case of brain abscess due to Gemella haemolysans and Bacteroides species in a 60-year-old-immunocompetent man who underwent dental procedures. The patient completely recovered following intravenous therapy with ampicillin and metronidazole for 6 weeks.

PMID: 15131228 [PubMed - indexed for MEDLINE]

Selection for high-level resistance by chronic triclosan exposure is not universal.

J Antimicrob Chemother. 2004 May;53(5):772-7

Authors: McBain AJ, Ledder RG, Sreenivasan P, Gilbert P

OBJECTIVES: To investigate the effect of triclosan exposure on the antimicrobial susceptibilities of numerically important dental bacteria. METHODS: A gradient plate technique was used to expose Fusobacterium nucleatum, Lactobacillus rhamnosus, Neisseria subflava, Porphyromonas gingivalis, Actinomyces naeslundii, Prevotella nigrescens, Streptococcus oralis, Streptococcus sanguis, Streptococcus mutans and Veillonella dispar repeatedly to escalating, sublethal concentrations of triclosan. Escherichia coli ATCC 8739 was included as an organism showing the triclosan resistance development trait. MIC values towards chlorhexidine, metronidazole and tetracycline were determined before and after biocide exposure. RESULTS: N. subflava, Pr. nigrescens Po. gingivalis and E. coli were highly susceptible to triclosan (MIC range 0.1-3.9 mg/L), whereas the lactobacillus and S. mutans were less susceptible (MIC range 15.6-20.8 mg/L). Triclosan exposure resulted in a highly significant ( approximately 400-fold) reduction in triclosan susceptibility (P < 0.01) for the positive control E. coli, although its MICs towards chlorhexidine, metronidazole and tetracycline were not significantly altered. Minor ( approximately two-fold) decreases in triclosan susceptibility (MIC) occurred for Pr. nigrescens and in S. sanguis and S. oralis (MBC). Mean changes in susceptibilities (MIC and MBC) of the oral species to chlorhexidine, metronidazole and tetracycline did not exceed two-fold, although chlorhexidine MBCs for S. sanguis were markedly, but transiently, increased. CONCLUSIONS: These data fail to demonstrate biologically significant drug resistance in triclosan-exposed bacteria and suggest that markedly decreased triclosan susceptibility, although confirmed for E. coli, is not a universal phenomenon. Other bacteria possibly possess more susceptible targets than FabI that are highly conserved, which may govern triclosan activity.

PMID: 15117935 [PubMed - indexed for MEDLINE]

Effects of a chlorhexidine gluconate-containing mouthwash on the vitality and antimicrobial susceptibility of in vitro oral bacterial ecosystems.

Appl Environ Microbiol. 2003 Aug;69(8):4770-6

Authors: McBain AJ, Bartolo RG, Catrenich CE, Charbonneau D, Ledder RG, Gilbert P

Oral bacterial microcosms, established using saliva inocula from three individuals, were maintained under a feast-famine regime within constant-depth film fermenters. Steady-state communities were exposed four times daily, postfeeding, to a chlorhexidine (CHX) gluconate-containing mouthwash (CHXM) diluted to 0.06% (wt/vol) antimicrobial content. The microcosms were characterized by heterotrophic plate counts and PCR-denaturing gradient gel electrophoresis (DGGE). CHXM caused significant decreases in both total anaerobe and total aerobe/facultative anaerobe counts (P < 0.05), together with lesser decreases in gram-negative anaerobes. The degree of streptococcal and actinomycete inhibition varied considerably among individuals. DGGE showed that CHXM exposure caused considerable decreases in microbial diversity, including marked reductions in Prevotella sp. and Selenomonas infelix. Pure-culture studies of 10 oral bacteria (eight genera) showed that Actinomyces naeslundii, Veillonella dispar, Prevotella nigrescens, and the streptococci were highly susceptible to CHX, while Lactobacillus rhamnosus, Fusobacterium nucleatum, and Neisseria subflava were the least susceptible. Determination of the MICs of triclosan, CHX, erythromycin, penicillin V, vancomycin, and metronidazole for microcosm isolates, before and after 5 days of CHXM exposure, showed that CHXM exposure altered the distribution of isolates toward those that were less susceptible to CHX (P < 0.05). Changes in susceptibility distributions for the other test agents were not statistically significant. In conclusion, population changes in plaque microcosms following repeated exposure to CHXM represented an inhibition of the most susceptible flora with a clonal expansion of less susceptible species.

PMID: 12902270 [PubMed - indexed for MEDLINE]

Identifying rosacea: what all dentists should know.

J Am Dent Assoc. 2003 May;134(5):603-7; quiz 632

Authors: Fuchs SS

BACKGROUND: Dentists frequently encounter adult patients who have facial rosacea. This common dermatologic condition can undermine a patient's appearance. Although rosacea can be progressive, the condition responds well to treatment, especially when started early. RESULTS: This article will help dentists recognize rosacea and differentiate it from other dermatologic disorders. Clinicians then will be able to refer patients suspected of having rosacea to the appropriate medical specialist for confirmation of the diagnosis and treatment. CONCLUSION: Dentists can provide a service to patients to improve their overall health and appearance by early recognition of this condition. CLINICAL IMPLICATIONS: Recognizing rosacea in dental patients and properly referring them for diagnosis and treatment constitutes a medical service that is relatively easy for dentists to perform. This service, in addition to others, such as measuring blood pressure, will make the dental examination more comprehensive.

PMID: 12785495 [PubMed - indexed for MEDLINE]

The nonsurgical treatment of patients with periodontal disease: results after five years.

J Am Dent Assoc. 2002 Mar;133(3):311-20

Authors: Loesche WJ, Giordano JR, Soehren S, Kaciroti N

BACKGROUND: In a previous study involving patients seen at the dental clinic of the Detroit Receiving Hospital, the authors found that 87 percent of teeth initially recommended for surgery or extraction were spared those treatments by a combination of debridement and short-term usage of antimicrobial agents. The objective of the present study was to determine how long the surgery-sparing benefits of less invasive treatment would persist. METHODS: Ninety of these patients were scheduled for maintenance therapy at three-month intervals over a five-year period. They were evaluated periodically for surgical needs by a clinician who was not aware of the nonsurgical periodontal treatment the patient had received. RESULTS: The initial treatment benefits were sustained, as the number of teeth needing periodontal surgery or extraction was 0.06 teeth per patient after 1.1 year, 0.22 after 2.3 years, 0.51 after 3.6 years and 0.86 after 5.1 years. CONCLUSIONS: A noninvasive treatment regimen for an anaerobic infection in teeth seriously compromised by periodontal disease resulted in a reduced need for surgery or tooth extraction for at least five years after completion of the initial treatment.

PMID: 11934186 [PubMed - indexed for MEDLINE]

Can audit improve antibiotic prescribing in general dental practice?

Br Dent J. 2001 Sep 8;191(5):253-5

Authors: Palmer NA, Dailey YM, Martin MV

OBJECTIVE: To investigate whether clinical audit can improve general dental practitioners' prescribing of antibiotics. DESIGN: An intervention study carried out in general dental practice in the North West of England. METHOD: Information was collected over an initial six-week period from 175 general dental practitioners on their current antibiotic prescribing practices. The information collected was the antibiotic prescribed including dose, frequency and duration, the clinically presenting signs and conditions, the medical history (if for prophylaxis), and any other reasons for prescribing. This was compared to the practitioners' antibiotic prescribing for a further six-week period following an audit, which included an educational component and the issuing of guidelines. RESULTS: During the initial period practitioners issued 2316 prescriptions for antibiotics. This was reduced by 42.5% to 1330 during the audit. The majority of the antibiotics (81%) for both periods were prescribed for therapeutic reasons. The most commonly prescribed antibiotics were amoxycillin (57.6%), metronidazole (23.8%), penicillin (9.3%), erythromycin (4.8%) and a combination of amoxycillin and metronidazole (1.7%). The antibiotic regimens used by practitioners were significantly changed by the audit (P<0.001) and there was a significant reduction in the number of prescriptions (P<0.05) which did not conform to national guidelines. CONCLUSIONS: The results from this investigation support the conclusion that clinical audit, with the issuing of guidelines and an educational component, can change prescribing practices leading to a more rational and appropriate use of antibiotics in general dental practice.

PMID: 11575760 [PubMed - indexed for MEDLINE]

Clonal infection with Actinobacillus actinomycetemcomitans following periodontal therapy.

J Dent Res. 1999 Sep;78(9):1518-24

Authors: Ehmke B, Schmidt H, Beikler T, Kopp C, Karch H, Klaiber B, Flemmig TF

Mechanical debridement results in a shift of the bacterial composition in the periodontal pocket on the species level. It is unknown, however, whether a clonal change within a species could lead to the emergence of strains with different levels of virulence. Therefore, in the present study, the genetic variability of Actinobacillus actinomycetemcomitans was assessed and strains identified which were associated with periodontal disease progression following periodontal therapy, i.e., refractory periodontitis. Twenty adult patients with untreated periodontitis and subgingival colonization of A. actinomycetemcomitans were randomly assigned to receive full-mouth scaling alone or scaling with an adjunctive antimicrobial therapy. Both groups received supportive periodontal therapy at 3, 6, 9, 12, 18, and 24 months. Subgingival plaque samples were taken at every visit; venous blood was obtained at 24 months only. A. actinomycetemcomitans isolates were typed by the RAPD method, and antibody reactivity against outer membrane proteins was assessed by immunoblot analysis. Eleven distinct RAPD patterns were found in 18 patients completing the study. All patients harbored only one A. actinomycetemcomitans genotype, and within each patient this genotype persisted throughout the 24-month observation period. No differences in the expression of antibody reactivity against outer membrane proteins were found between strains isolated at baseline and at 24 months. Three genotypes were associated with reduced survival rates of teeth without probing attachment loss of 2 mm or more. The results indicated that (i) most patients harbored only one A. actinomycetemcomitans genotype; (ii) the genotype persisted following therapy; and (iii) only some genotypes were associated with refractory periodontitis.

PMID: 10512386 [PubMed - indexed for MEDLINE]

Adverse drug interactions in dental practice: interactions involving antibiotics. Part II of a series.

J Am Dent Assoc. 1999 Feb;130(2):236-51

Authors: Hersh EV

BACKGROUND: The prudent use of antibiotics is an integral part of dental practice. While these agents generally are considered safe in the dental setting, their use can result in interactions that can lead to serious morbidity in dental patients. METHODS: The faculty of a symposium entitled "Adverse Drug Interactions in Dentistry: Separating the Myths From the Facts" did an extensive literature review on drug interactions. Through this, they were able to establish a significance rating of alleged adverse drug interactions as they relate to dentistry, based on their scientific documentation and severity of effect. The author of this article focused on antibiotics. RESULTS: Most of the reported drug interactions discussed in this article are well-documented by clinical studies. It is particularly important that dentists be aware of the potentially serious and life-threatening interactions of the antibiotics erythromycin, clarithromycin and metronidazole, and of the antifungal agents ketoconazole and itraconazole, with a host of other drugs whose metabolism is impaired by these antimicrobial agents. In contrast, the alleged ability of commonly employed antibiotics to reduce the effectiveness of oral contraceptive agents is not adequately supported by clinical research. It still is recommended, however, that clinicians discuss this possible interaction with their patients, as it might represent a relatively rare event that cannot be discerned in clinical trials. CONCLUSIONS: Potentially serious adverse drug interactions can occur between antimicrobial agents used in dental practice and other drugs patients are taking for a variety of medical conditions. CLINICAL IMPLICATIONS: It is important that dentists stay abreast of potential drug interactions involving antibiotics to avoid serious morbidity among their patients.

PMID: 10036847 [PubMed - indexed for MEDLINE]

Use of PCR and culture to detect Helicobacter pylori in naturally infected cats following triple antimicrobial therapy.

Antimicrob Agents Chemother. 1996 Jun;40(6):1486-90

Authors: Perkins SE, Yan LL, Shen Z, Hayward A, Murphy JC, Fox JG

Helicobacter pylori causes gastritis and peptic ulcers and is linked to gastric cancer. Domestic cats from a commercial source were found to be naturally infected with H. pylori, and studies were undertaken to eradicate H. pylori from infected cats by using triple antimicrobial therapy. Eight cats infected with H. pylori were used in the study. Six cats received a 21-day course of oral amoxicillin, metronidazole, and omeprazole, and two cats served as controls. Two weeks and 4 weeks posttreatment (p.t.), all six treated cats were negative at several sites (saliva, gastric juice, and gastric mucosa) for H. pylori by culture. However, as determined by PCR with primers specific for the 26-kDa product, the majority of cats at 2 and 4 weeks p.t. had gastric fluid samples which were positive for H. pylori and three of three cats at 2 weeks p.t. had dental plaque which was positive for H. pylori. At 6 weeks p.t., all six cats had H. pylori-negative cultures for samples from several gastric sites taken at necropsy, and only one cat had H. pylori cultured from gastric juice. PCR analysis revealed that five of six cats had H. pylori DNA amplification products from plaque, saliva, and/or gastric fluid samples. Negative bacterial cultures for cats for which there was demonstrable PCR amplification of H. pylori DNA may reflect the inability of in vitro culture techniques to isolate small numbers of H. pylori organisms, focal colonization at sites not cultured, or a failure of the antibiotics to successfully eradicate H. pylori from extragastric sites which allowed subsequent recolonization of the stomach after cessation of therapy. Alternatively, the treatment strategy may have induced in vivo viable but nonculturable coccoid forms of H. pylori. The H. pylori cat model should allow further studies to test these hypotheses as well as the efficacies of other combined therapeutic regimens. Also, because 100% of these cats were naturally infected with H.pylori, this model should prove useful in exploring mechanisms whereby human populations in underdeveloped countries, which have H. pylori infection rates approaching 100%, have a high rate of recurrence of H. pylori infection after use of prescribed antibiotic therapies that successfully eradicate H. pylori in individuals in developed countries.

PMID: 8726024 [PubMed - indexed for MEDLINE]

Passive immunization with monoclonal antibodies against Porphyromonas gingivalis in patients with periodontitis.

Infect Immun. 1996 Feb;64(2):422-7

Authors: Booth V, Ashley FP, Lehner T

Selective inhibition of recolonization of Porphyromonas gingivalis was investigated by topical application of monoclonal antibody (MAb). To select a MAb to P. gingivalis with the potential for recognizing most strains of P. gingivalis, we examined seven MAbs, one of which (MAb 61BG 1.3) recognized all 22 laboratory strains and serotypes of P. gingivalis tested as well as 105 human clinical isolates. A comparative study of the number of P. gingivalis bacteria identified by conventional culture and immunofluorescence with MAb 61BG 1.3 showed a very significant correlation between the two methods (Spearman r = 0.85, P < 0.001). Fourteen patients with periodontitis, who harbored P. gingivalis in their subgingival plaque, were treated by root planing and with metronidazole to suppress any detectable P. gingivalis. In this double-blind study, the patients were then divided randomly into two groups; one was treated with MAb to P. gingivalis, and the other was treated with saline. Each patient had four subgingival applications of 3 micrograms of MAb (or saline) per tooth at 1, 3, 7, and 10 days after P. gingivalis was suppressed. The number of P. gingivalis bacteria was then monitored, and significantly less recolonization of the sites with the most severe periodontitis was found in the MAb-treated patients than in the control patients (P < 0.01). This was evident at 6 and 9 months after the application of MAb, but by 12 months, P. gingivalis, was also found to recolonize these sites in two of the MAb-treated patients. The effect of MAb was specific to P. gingivalis, since the numbers of spirochetes were not significantly different between the two groups. However, no significant difference in any clinical periodontal indices between the immunized and control patients at 6 and 12 months was observed. This is the first demonstration that a putative periodontal pathogen can be selectively prevented from recolonization for up to 9 months in sites with the most severe periodontitis. This strategy could be used to establish directly in humans whether a microorganism is involved in the pathogenesis of periodontitis, by repeated application of the corresponding MAb at about 6-month intervals and by comparing the clinical indices between the MAb-treated and control patients.

PMID: 8550186 [PubMed - indexed for MEDLINE]

Salivary levels of suspected periodontal pathogens in relation to periodontal status and treatment.

J Dent Res. 1995 Nov;74(11):1789-95

Authors: von Troil-Lind&#xE9;n B, Torkko H, Alaluusua S, Jousimies-Somer H, Asikainen S

The primary ecological niche for suspected periodontal pathogens seems to be the subgingival area, even though periodontal pathogens are also frequently recovered from saliva. The interrelationship of different periodontal conditions and the salivary levels of suspected periodontal pathogens is not known. In the present study, salivary levels of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Campylobacter rectus, and Peptostreptococcus micros were determined by bacterial culture and related to clinical periodontal status in 40 subjects with either advanced, moderate, or initial/no periodontitis. Culture-positive subjects harbored the 5 bacterial species in mean numbers ranging from 2 x 10(5) to 6 x 10(7) colony-forming units (CFU)/mL saliva. A. actinomycetemcomitans was found in none and P. gingivalis in one of the subjects with initial periodontitis, whereas both species were found in 33% and 44%, respectively, of the subjects with moderate periodontitis and in 60% and 40%, respectively, of the subjects with advanced periodontitis. The mean numbers of CFU/mL of P. intermedia, C. rectus and P. micros were significantly higher in subjects with advanced periodontitis than in subjects with initial/no periodontitis. Ten patients with advanced periodontitis were treated mechanically and with adjunctive systemic metronidazole, and were re-examined 1 and 6 months after treatment. Periodontal treatment eradicated or significantly reduced the levels of salivary periodontal pathogens for half a year, whereas in untreated subjects, the levels and the detection frequencies generally remained fairly stable. In conclusion, the results showed that the salivary levels of periodontal pathogens reflect the periodontal status of the patient.

PMID: 8530742 [PubMed - indexed for MEDLINE]

Experience with a novel selective medium for isolation of Actinomyces spp. from medical and dental specimens.

J Clin Microbiol. 1995 Jun;33(6):1613-6

Authors: Lewis R, McKenzie D, Bagg J, Dickie A

A selective medium containing mupirocin and metronidazole was evaluated for the isolation of Actinomyces spp. from clinical material. The study was a one-year prospective comparison of the method with existing methods, which use nonselective media, at a general hospital and a dental hospital. Significantly more Actinomyces spp. were isolated on the selective medium than on nonselective media from both dental specimens and intrauterine contraceptive devices. However, differentiating between Actinomyces spp. and related nonsporulating gram-positive rods remains a slow and sometimes uncertain process which can introduce lengthy delays in reporting.

PMID: 7650197 [PubMed - indexed for MEDLINE]

Topical metronidazole for arterial insufficiency ulcers.

J Am Osteopath Assoc. 1995 Mar;95(3):201-3

Authors: Kaplan B, Gibson LB

The use of topical metronidazole has been limited to the treatment of acne rosacea, infected foot ulcers associated with diabetes mellitus, varicose veins, postirradiation ulcers, and dental conditions since the Food and Drug Administration approved the drug in 1988. Because of this agent's apparent effectiveness in treating anaerobic bacterial infections in such ulcers, the authors believed that treatment of arterial insufficiency ulcers with a solution of topical metronidazole would be a rational approach. They describe a 30-year-old man in whom bilateral lower extremity cellulitis developed as a result of arterial insufficiency. The patient's ulcers were unresponsive to intravenously administered antibiotics and whirlpool therapy. However, when a topical solution of metronidazole was administered, the ulcers began to heal and epithelialization at the ulcer sites occurred. The authors review others' studies concerning clinical use of topical metronidazole and suggest that further study is warranted. To the authors' knowledge, topical metronidazole solution for the treatment of arterial insufficiency and venous stasis ulcers has not been previously reported.

PMID: 7751170 [PubMed - indexed for MEDLINE]

The utility of the BANA test for monitoring anaerobic infections due to spirochetes (Treponema denticola) in periodontal disease.

J Dent Res. 1990 Oct;69(10):1696-702

Authors: Loesche WJ, Giordano J, Hujoel PP

Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus each possesses an enzyme(s) that hydrolyzes the synthetic substrate benzoyl-DL-arginine-naphthylamide (BANA). The presence of these organisms in a subgingival plaque sample can be determined by the ability of the plaque to hydrolyze BANA. In the present study, we describe the usefulness of the BANA test at various stages of a clinical trial of the efficacy of metronidazole in the treatment of periodontal disease. A BANA-positive test was significantly associated with high levels and proportions of spirochetes in the plaque, so that it provided information comparable with that which could be obtained by a microscopic examination of the plaque. Patients with such anaerobic spirochetal infections were randomly assigned to a group receiving either metronidazole or placebo (250 mg, three times a day) for one week and whose teeth were scaled and root-planed. The advantages of the decision that metronidazole be used were apparent from the comparison with the results obtained in the patients who received only the scaling and root planing. The initially BANA-positive teeth in the patients treated with metronidazole, scaling, and root planing gained attachment and exhibited a significant reduction in the need for periodontal surgery, when compared with the BANA-positive teeth in the patients who received only placebo, scaling, and root planing. After the conclusion of this therapy, those teeth with persistent BANA-positive plaques had significantly higher proportions and levels of spirochetes than did the teeth with BANA-negative plaques.(ABSTRACT TRUNCATED AT 250 WORDS)

PMID: 2212216 [PubMed - indexed for MEDLINE]

Cost-effectiveness analysis of periodontal disease control.

J Dent Res. 1987 Nov;66(11):1630-5

Authors: Antczak-Bouckoms AA, Weinstein MC

Cost-effectiveness analysis was used to evaluate alternative methods of periodontal disease control. The alternatives considered included non-surgical and surgical procedures as well as the use of antimicrobial agents. Data on costs were obtained from American Dental Association publications of average charges for periodontal services. The concept of quality-adjusted tooth-years (QATYs) was developed to provide an outcome measure which could be compared across treatments. The conclusions of this analysis are as follows: (1) Conservative non-surgical treatments for periodontal disease control not only have costs lower than surgical alternatives, as would be expected, but also maximize expected quality-adjusted tooth-years over a wide range of estimates; (2) antimicrobial therapy used as an adjunct to non-surgical treatment is likely to be both effective and cost-effective; and (3) quality of tooth-years is a critical consideration in the determination of outcome of periodontal treatment. For example, when tooth-years are not adjusted for quality, differences between treatments are diminished, and surgical treatment becomes as good as or better than more conservative treatments for some levels of disease severity.

PMID: 10872396 [PubMed - indexed for MEDLINE]

New medium for isolation of Actinomyces viscosus and Actinomyces naeslundii from dental plaque.

J Clin Microbiol. 1978 Jun;7(6):514-8

Authors: Kornman KS, Loesche WJ

Metronidazole (10 microgram/ml) and cadmium sulfate (20 microgram/ml) were added to a gelatin-based medium to select for microaerophilic Actinomyces species from dental plaque samples. The new medium (GMC), when incubated anaerobically, allowed 98% recovery of seven pure cultures of Actinomyces viscosus and 73% recovery of eight pure cultures of Actinomyces naeslundii, while suppressing 76% of the total count of other organisms in dental plaque samples. In 203 plaque samples, recoveries of A. viscosus and A. naeslundii on GMC and another selective medium for oral Actinomyces (CNAC-20) were compared. Recovery of A. viscosus was comparable on the two media. Recovery of A. naeslundii was significantly higher on GMC than CNAC-20 (P is less than 0.001), and GMC allowed a more characteristic cell morphology of both organisms. GMC medium appears to be useful for the isolation and presumptive identification of A. viscosus and A. naeslundii from dental plaque.

PMID: 670376 [PubMed - indexed for MEDLINE]