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Biomedical subjects

M L Barnett

Publications and source records attributed to M L Barnett.

At least 19 recordsLinked to original sources
PubMed2000

Effect of an essential oil-containing antiseptic mouthrinse on plaque and salivary Streptococcus mutans levels.

BACKGROUND: Clinical studies in which antimicrobial mouthrinses were shown to have significant antiplaque activity most frequently have used gingivitis as the clinically relevant endpoint. However, there is evidence to suggest that mouthrinses containing active agents effective against Streptococcus mutans, such as chlorhexidine, may also have a role in inhibiting dental caries. This clinical study was conducted to determine the effect of 2x-daily rinsing with an essential oil-containing antiseptic mouthrinse (Listerine Antiseptic) on levels of recoverable S. mutans and total streptococci in supragingival interproximal plaque and in saliva. Additionally, a follow-up in vitro study is reported which determined whether a differential susceptibility to the antiseptic mouthrinse exists among different strains of streptococci. METHOD: Following baseline saliva and plaque sampling for quantification of recoverable S. mutans and total streptococci, 29 qualifying subjects were randomly assigned either the essential oil mouthrinse or a sterile water control. They rinsed with 20 ml for 30s 2 x daily for 11 days and once on the 12th day, in addition to their usual oral hygiene procedures. On day 12, saliva and plaque samples were again collected and microbiological quantification performed. The procedures were repeated with the alternate rinse after a 1-week washout period. RESULTS: The essential oil mouthrinse produced respective reductions of 69.9% and 75.4% in total recoverable streptococci and in S. mutans in plaque, and corresponding reductions of 50.8% and 39.2% in saliva. The in vitro study revealed that streptococci from the mutans group were more susceptible to the bactericidal activity of the essential oil mouthrinse than streptococci from the mitis group. CONCLUSIONS: As antimicrobial mouthrinses are most frequently recommended to patients whose mechanical oral hygiene procedures are not adequate for the control of supragingival plaque and gingivitis, this study provides an additional rationale for the inclusion of the essential-oil mouthrinse as an adjunct to daily oral hygiene procedures.

Adult↗
PubMed2000

Determination of the in situ bactericidal activity of an essential oil mouthrinse using a vital stain method.

BACKGROUND: Recent research has indicated that bacteria within a biofilm may undergo changes in susceptibility to antimicrobial agents when compared to planktonic forms. This study was conducted to determine the bactericidal effect of an essential oil-containing mouthrinse (Listerine Antiseptic) on dental plaque bacteria in situ. METHODS: 1-day-old plaque in 17 subjects was sampled at baseline from the buccal surfaces of diagonally contralateral maxillary and mandibular bicuspids and 1st molars. Subjects were then randomly assigned either an essential oil mouthrinse or a sterile saline negative control and rinsed under supervision with 20 ml for 30 s. 30 min later, plaque was sampled from the remaining contralateral posterior teeth. Subjects repeated these procedures with their respective alternate rinse after 1 week. Pooled plaque samples from each subject at each sampling period were stained with a commercially-available fluorescent stain which fluoresces live and dead bacteria green and red, respectively. The stained plaque specimens were analyzed using computerized image analysis. A separate in vitro study was conducted to determine the relationship between the % red stain per sample and bacterial viability. RESULTS: Analysis of vital stained plaque specimens indicated that following rinsing with the essential oil mouthrinse, 78.7% of bacteria were dead compared to 27.9% following rinsing with the negative control (p<0.001). The in vitro findings demonstrated that the % red stain per sample is reflective of actual bacterial kill. CONCLUSIONS: This study confirms the findings of previous in vitro and in vivo studies which demonstrated the essential oil mouthrinse to have significant biocidal activity against oral micro-organisms. These studies all support the primacy of a bactericidal mechanism in producing the plaque and gingivitis reductions observed in numerous clinical trials conducted on the essential oil mouthrinse.

Anti-Infective Agents, Local↗
PubMed2000

Effect of an essential oil-containing antiseptic mouthrinse on induction of platelet aggregation by oral bacteria in vitro.

BACKGROUND: With an increasing body of data suggesting an association between periodontitis and cardiovascular disease, studies have been conducted to elucidate potential mechanisms by which oral bacteria might exert systemic effects. 2 oral bacteria, Streptococcus sanguis and Porphyromonas gingivalis, have been shown to induce platelet aggregation in vitro. This study was conducted to determine the effect of treatment with an essential oil mouthrinse (Listerine Antiseptic) on the platelet-aggregating activity of these organisms. METHOD: Bacteria were grown under standard culture conditions. S. sanguis ATCC strain 10556 was exposed for 3 min to the essential oil mouthrinse at either full strength or a 1:1 dilution, while P. gingivalis FDC strain 381 was exposed to the essential oil mouthrinse at a 1:10 dilution. Positive control cells were treated with Hanks balanced salt solution (HBSS). Aggregation was measured using a recording platelet aggregometer. The assay of each organism in its respective mouthrinse dilution(s) or HBSS was repeated 5 times. RESULTS: In all cases, the HBSS-treated organisms induced platelet aggregation, with mean(+/-S.E.) lag times of 12.30 (+/-1.36) min and 11.36 (+/-0.58) min for P. gingivalis and S. sanguis, respectively. In contrast, treatment with the essential oil mouthrinse completely inhibited the platelet aggregating activity of P. gingivalis and of S. sanguis exposed to the 1:1 mouthrinse dilution in all assays; the aggregating activity of S. sanguis treated with full-strength mouthrinse was completely inhibited in 4 of 5 assays, and inhibited by 75% in the 5th, for a mean inhibition of 95 +/- 1.5%. CONCLUSION: This study provides additional evidence that the essential oil mouthrinse can interfere with bacterial cell surface-associated activities which may have clinical relevance.

Drug Combinations↗
PubMed1999

Hypercalcemia.

OBJECTIVES: To provide a review of hypercalcemia of malignancy, including the incidence, pathophysiology, signs and symptoms, treatment, and nursing interventions. DATA SOURCES: Research studies, review articles, proceedings from nursing conferences, and book chapters. CONCLUSIONS: Hypercalcemia of malignancy is difficult to diagnose because the signs and symptoms are similar to those experienced by patients with end-stage cancers. Knowing the cancers and histologic cell types that are at high risk for hypercalcemia assists in early diagnosis and treatment. Treatment decisions must consider potential benefits and their risks and affect on quality of life. IMPLICATIONS FOR NURSING PRACTICE: Hypercalcemia of malignancy as a metabolic oncologic emergency requires accurate assessment and rapid intervention. Early recognition by the patient, family, and health care professionals can result in improved quality of life.

Bone Neoplasms↗
PubMed1999

Comparative antiplaque effectiveness of an essential oil and an amine fluoride/stannous fluoride mouthrinse.

The adjunctive use of antimicrobial mouthrinses to help control supragingival plaque and gingivitis has been shown to contribute significantly to patients' daily oral hygiene regimens. This controlled clinical study used an observer-blind, randomized, cross-over design in a 4-day plaque regrowth model to determine the relative efficacies of an essential oil-containing mouthrinse (Listerine Antiseptic) and an amine fluoride/stannous fluoride-containing mouthrinse (Meridol) in inhibiting the development of supragingival plaque. A 0.1% chlorhexidine mouthrinse (Chlorhexamed-Fluid) was used as a positive control, and a 5% hydroalcohol solution was used as a negative control. Dosing for each of the test mouthrinses was based on the manufacturers' label directions. Because the volume and rinse time for each of the test mouthrinses were different, each test mouthrinse had its own negative control group. On day 1 of each test period, subjects received an oral soft and hard tissue examination and a dental prophylaxis to remove all plaque, calculus, and extrinsic stain. Starting the same day, subjects refrained from all mechanical oral hygiene procedures for the next 4 days and rinsed 2x daily under supervision with their randomly-assigned mouthrinse. On day 5, each subject received a plaque assessment as well as an oral examination to assess side effects. Each test period was separated by a 2-week washout period. 23 volunteers with a median age of 26 years completed the study. Compared to the respective placebos, the median percent plaque reductions at 5 days were 23.0%, 12.2%, and 38.2% for the essential oil, amine/stannous fluoride, and chlorhexidine rinses, respectively. The plaque reductions seen in the essential oil and chlorhexidine rinse groups were statistically significant (p < 0.001), while the plaque reduction in the amine/stannous fluoride rinse group was not statistically significant (p > 0.05). Additionally, the essential oil rinse was significantly more effective (p < 0.001) than the amine/stannous fluoride rinse in inhibiting plaque accumulation in this clinical model.

Adult↗
PubMed1999

Comparative antimicrobial activity of an essential oil and an amine fluoride/stannous fluoride mouthrinse in vitro.

Although laboratory studies are not necessarily predictive of clinical activity; they can help to elucidate mechanisms underlying clinical activity when the latter has been established. In a recent clinical study, an essential oil mouthrinse (Listerine Antiseptic) was shown to be significantly more effective than an amine fluoride/stannous fluoride mouthrinse (Meridol) in inhibiting supragingival plaque formation. This paper reports the results of laboratory studies comparing the antimicrobial effectiveness of these 2 mouthrinses using a kill kinetics assay and a plaque biofilm kill assay. In both assays, the essential oil mouthrinse was considerably more effective than the amine fluoride/stannous fluoride mouthrinse. These findings are consistent with the results of the clinical trial and may help to explain the observed differences in clinical activity.

Amines↗
PubMed1998

Treatment of rheumatoid arthritis with oral type II collagen. Results of a multicenter, double-blind, placebo-controlled trial.

OBJECTIVE: Oral administration of cartilage-derived type II collagen (CII) has been shown to ameliorate arthritis in animal models of joint inflammation, and preliminary studies have suggested that this novel therapy is clinically beneficial and safe in patients with rheumatoid arthritis (RA). The present study was undertaken to test the safety and efficacy of 4 different dosages of orally administered CII in patients with RA. METHODS: Two hundred seventy-four patients with active RA were enrolled at 6 different sites and randomized to receive placebo or 1 of 4 dosages (20, 100, 500, or 2,500 microg/day) of oral CII for 24 weeks. Efficacy parameters were assessed monthly. Cumulative response rates (percentage of patients meeting the criteria for response at any time during the study) were analyzed utilizing 3 sets of composite criteria: the Paulus criteria, the American College of Rheumatology criteria for improvement in RA, and a requirement for > or = 30% reduction in both swollen and tender joint counts. RESULTS: Eighty-three percent of patients completed 24 weeks of treatment. Numeric trends in favor of the 20 microg/day treatment group were seen with all 3 cumulative composite measures. However, a statistically significant increase (P = 0.035) in response rate for the 20 microg/day group versus placebo was detected using only the Paulus criteria. The presence of serum antibodies to CII at baseline was significantly associated with an increased likelihood of responding to treatment. No treatment-related adverse events were detected. The efficacy seen with the lowest dosage is consistent with the findings of animal studies and with known mechanisms of oral tolerance in which lower doses of orally administered autoantigens preferentially induce disease-suppressing regulatory cells. CONCLUSION: Positive effects were observed with CII at the lowest dosage tested, and the presence of serum antibodies to CII at baseline may predict response to therapy. No side effects were associated with this novel therapeutic agent. Further controlled studies are required to assess the efficacy of this treatment approach.

Administration, Oral↗
PubMed1996

A pilot trial of oral type II collagen in the treatment of juvenile rheumatoid arthritis.

OBJECTIVE: To evaluate the efficacy of oral chicken type II collagen (CCII) in the treatment of juvenile rheumatoid arthritis (JRA). METHODS: Ten patients with active JRA were treated with CCII for 12 weeks. Efficacy parameters, which included swollen and tender joint count and score, grip strength, 50-foot walking time, duration of morning stiffness, and patient and physician global scores of disease severity, were assessed monthly. RESULTS: All patients completed the full course of therapy. Eight patients had reductions in both swollen and tender joint counts after 3 months of CCII. The mean changes from baseline in swollen and tender joint counts for the 8 responders at the end of the study were -61% and -54%, respectively. Mean values for other efficacy parameters also showed improvement from baseline. There were no adverse events that were considered to be treatment related. CONCLUSION: Oral CCII may be a safe and effective therapy for JRA, and its use in this disease warrants further investigation.

Administration, Oral↗
PubMed1996

Effects of sublethal exposure to an antiseptic mouthrinse on representative plaque bacteria.

Although the mechanism responsible for the clinical antiplaque efficacy of oral antiseptics is generally considered to be primarily one of bactericidal activity, it has been suggested that oral antiseptics may have additional effects on bacteria exposed to sublethal levels. Studies reported herein, investigated the effects of sublethal levels of an essential oil-containing antiseptic mouthrinse (Listerine Antiseptic, Warner-Lambert Co., Morris Plains, NJ) on selected activities of representative plaque microorganisms using in vitro models. These studies demonstrated that sublethal exposure to the tested oral antiseptic can have significant effects in reducing intergeneric coaggregation, increasing bacterial generation time, and extracting endotoxin from Gram-negative bacteria. These in vitro activities can be correlated with features of plaque formation and pathogenicity seen in vivo; however, additional studies will be necessary to confirm that these mechanisms are, in fact, operative clinically.

Aggregatibacter actinomycetemcomitans↗
PubMed1996

Suitability of gingival indices for use in therapeutic trials. Is bleeding a sine qua non?

A number of gingival indices have been described which include visual and invasive components, either separately or in combination. In selecting indices for use in gingivitis therapeutic trials, some investigators maintain that only invasive indices should be used, since indices that include a bleeding-on-provocation component are deemed to be the most objective. Other investigators, however, maintain that non-invasive indices are the more appropriate insofar as invasive procedures will not only disrupt the plaque at the gingival margin, but could also mildly traumatize the tissue and present an impediment to assessing examiner standardization and reproducibility. This paper discusses these aspects of gingivitis evaluation. The data indicate that all validated indices, whether invasive or non-invasive, have some degree of both objectivity and subjectivity. Therefore, the selection of an appropriate index will depend upon the ability of a given index to achieve the objectives of the clinical trial in which it is to be utilized.

Clinical Trials as Topic↗