A prospective, randomized clinical trial comparing two hyperbaric treatment protocols for carbon monoxide poisoning.

INTRODUCTION: The optimal hyperbaric oxygen (HBO2) treatment protocol for acute carbon monoxide (CO) poisoning is unknown. This is indicated by one study that found 18 different protocols to treat CO poisoning by North American multiplace hyperbaric facilities. A pilot study was conducted to evaluate the feasibility of randomizing patients to different protocols and to determine whether any large differences in clinical outcome were present between the two most common protocols. METHODS: Adult patients with accidental CO poisoning resulting in transient loss of consciousness, presentation to the emergency department within 12 hours, primary language English, high school education, and residence within 100 miles of the hyperbaric facility were recruited. Enrolled patients were randomized to one HBO2 treatment at 2.4 atmospheres absolute (atm abs) pressure with 90 minutes of 100% oxygen breathing vs. treatment by the US Air Force CO protocol (3.0 atm abs maximum pressure). A neurocognitive screening test was performed immediately after hyperbaric treatment and repeated 14-21 days later. RESULTS: From 1995 to 2002, 30 patients age 21 to 88 years were randomized, 18 to treatment at 2.4 atm abs and 12 to 3.0 atm abs. Average carboxyhemoglobin level for the population was 24.8 +/- 8.8% (mean +/- SD). Delay to hyperbaric treatment averaged 313 +/- 129 minutes. Neither variable was different between treatment groups. Six patients had abnormal neurocognitive testing immediately following hyperbaric treatment, 4 in the 2.4 atm abs group (22%) and 2 in the 3.0 atm abs group (17%) (P=0.71). One patient in each group demonstrated abnormality on delayed testing (p=0.75). One in each group did not return for follow-up. CONCLUSIONS: It is feasible to randomize CO-poisoned patients to different hyperbaric treatment protocols. Determination of differences in efficacy between treatment protocols will require a large multicenter trial with the use of detailed neurocognitive testing.

The incidence of venous gas emboli in recreational diving.

From 1989-91, the Divers Alert Network monitored recreational divers for Doppler-detected venous gas emboli (VGE) and depth-time profiles following multi-day, repetitive, multi-level exposures. A Spencer score >0 occurred in 61 of 67 subjects (91%) and 205 of 281 dives (73%). No subject developed decompression sickness (DCS) on monitored days although 102 dives (36.3%) scored at Spencer Grades 2 or 3 (High Bubble Grade, HBG). We recorded the depth-time profiles with Suunto dive computers and estimated exposure severity with a probabilistic decompression algorithm. The HBG incidence increased 53% over the range of exposure severity (p < 0.001) in the divers, was approximately 20% higher for repetitive dives than for first dives, and decreased approximately 25% over the 6-8 days of multi-day diving (p < 0.001) suggesting a phenomenon similar to DCS adaptation. The observed HBG incidence was approximately 20% higher for males than females. Older male divers had a 25% increase in observed incidence of HBG while older female divers showed a 55% increase when compared to their younger counterparts.

Diving methods and decompression sickness incidence of Miskito Indian underwater harvesters.

Diving conditions, dive profiles, and symptoms of decompression sickness (DCS) in a group of Miskito Indian underwater seafood harvesters are described. Dive profiles for 5 divers were recorded with dive computers, and DCS symptoms were assessed by neurological examination and interview. Divers averaged 10 dives a day over a 7-day period with a mean depth of 67 +/- 7 FSW (306 +/- 123 kPa) and average in-water time of 20.6 +/- 6.3 minutes. Limb pain was reported on 10 occasions during 35 man-days of diving. Symptoms were typically managed with analgesic medication rather than recompression. Indices of the decompression stress were estimated from the recorded profiles using a probabilistic model. We conclude that the dives were outside the limits of standard air decompression tables and that DCS symptoms were common. The high frequency of limb pain suggests the potential for dysbaric bone necrosis for these divers.

Dietary vitamin C and the risk for periodontal disease.

BACKGROUND: Vitamin C has long been a candidate for modulating periodontal disease. Studies of scorbutic gingivitis and the effects of vitamin C on extracellular matrix and immunologic and inflammatory responses provide a rationale for hypothesizing that vitamin C is a risk factor for periodontal disease. METHODS: We evaluated the role of dietary vitamin C as a contributing risk factor for periodontal disease utilizing the Third National Health and Nutrition Examination Survey (NHANES III) which is representative of the U.S. civilian, non-institutionalized population. RESULTS: A sample of 12,419 adults (20 to 90+ years of age), with dental measurements and assessment of dietary information as well as demographic and medical histories were included in the studies. Dietary vitamin C was estimated by a 24-hour dietary record. Individuals with periodontal disease were arbitrarily defined as those who had mean clinical attachment levels of > or =1.5 mm. Using multiple logistic regression analysis, we found a relationship between reduced dietary vitamin C and increased risk for periodontal disease for the overall population (odds ratio [OR] = 1.19; 95% CI: 1.05 to 1.33). Current and former tobacco users who were taking less dietary vitamin C showed an increased risk of periodontal disease with OR of 1.28, 95% CI: 1.04 to 1.59 for former smokers, and an OR of 1.21, 95% CI: 1.02 to 1.43 for current tobacco users. There was a dose-response relationship between the levels of dietary vitamin C and periodontal disease with an OR of 1.30 for those taking 0 to 29 mg of vitamin C per day, to 1.16 for those taking 100 to 179 mg of vitamin C per day as compared to those taking 180 mg or more of vitamin C per day. CONCLUSION: Dietary intake of vitamin C showed a weak, but statistically significant, relationship to periodontal disease in current and former smokers as measured by clinical attachment. Those taking the lowest levels of vitamin C, and who also smoke, are likely to show the greatest clinical effect on the periodontal tissues.

Calcium and the risk for periodontal disease.

BACKGROUND: Dietary calcium has long been a candidate to modulate periodontal disease. Animal as well as human studies of calcium intake, bone mineral density, and tooth loss provide a rationale for hypothesizing that low dietary intake of calcium is a risk factor for periodontal disease. METHODS: We evaluated the role of dietary calcium intake as a contributing risk factor for periodontal disease utilizing the Third National Health and Nutrition Examination Survey (NHANES III), which is representative of the U.S. civilian non-institutionalized population. Dietary calcium intake was determined from a 24-hour dietary recall. The U.S. Department of Agriculture Nutrient Database was used as a source of nutrient composition data. Periodontal disease was measured by attachment loss. In addition, serum calcium was assessed using venous blood samples. Logistic regression analysis was used to examine the association between periodontal disease and dietary calcium intake or serum calcium levels after adjusting for covariants including age, gender, tobacco consumption, and gingival bleeding. RESULTS: The association of lower dietary calcium intake with periodontal disease was found for young males and females (20 to 39 years of age), and for older males (40 to 59 years of age). The relationship between low dietary calcium intake and increased levels of periodontal disease showed an estimated odds ratio (OR) of 1.84 (95% CI: 1.36 to 2.48) for young males, 1.99 (95% CI: 1.34 to 2.97) for young females, and 1.90 (95% CI: 1.41 to 2.55) for the older group of males. These odds ratios were adjusted for gingival bleeding and tobacco consumption. The dose response was also seen in females, where there was 54% greater risk of periodontal disease for the lowest level of dietary calcium intake (2 to 499 mg) and 27% greater risk in females who took moderate levels of dietary calcium (500 to 799 mg) as compared to those who took 800 mg or more dietary calcium per day. A statistically significant association between low total serum calcium and periodontal disease was found in younger females aged 20 to 39 with OR = 6.11 (95% CI: 2.36 to 15.84) but not for males or older females, after adjusting for tobacco use, gingival bleeding, and dietary calcium intake. CONCLUSIONS: These results suggest that low dietary intake of calcium results in more severe periodontal disease. Further studies will be needed to better define the role of calcium in periodontal disease and to determine the extent to which calcium supplementation will modulate periodontal disease and tooth loss.

Effects of weather on incidence of attempted suicide by carbon monoxide poisoning.

Depressive illness and related suicide attempts have been reported to have seasonal variation, possibly related to weather. This study sought to determine the effects of weather and time of year on suicide attempts by carbon monoxide (CO) poisoning. Cases of patients in western Washington State attempting suicide by CO poisoning and referred to a regional hyperbaric oxygen treatment center from 1981-1995 were reviewed retrospectively. Information from the National Climatic Data Center was used to compare date of treatment to local weather data on the day of attempted suicide and on each day of the preceding week. The study population consisted of 264 patients attempting suicide by CO poisoning on 251 days of the 15-yr period. Mean and total precipitation in the preceding 7 days strongly correlated with attempted suicide rate, with incident rate ratios ranging from 1.75 to 2.77 and 1.14 to 1.75, respectively (P values <0.05). A decrease in minimum daily temperature also correlated with attempted suicide rate. No other weather variables showed significant correlation with dates of CO suicide attempts. February, March, and October were seen to be separate factors related to a higher incidence of attempted suicide by CO poisoning. Precipitation in Seattle, change in minimum temperature, and month of the year correlated with the regional incidence of suicide attempts with CO poisoning.

Relationship of stress, distress and inadequate coping behaviors to periodontal disease.

BACKGROUND: The association of stress, distress, and coping behaviors with periodontal disease was assessed. METHODS: A cross-sectional study of 1,426 subjects between the ages of 25 and 74 years in Erie County, New York, was carried out to assess these relationships. Subjects were asked to complete a set of 5 psychosocial questionnaires which measure psychological traits and attitudes including discrete life events and their impact; chronic stress or daily strains; distress; coping styles and strategies; and hassles and uplifts. Clinical assessment of supragingival plaque, gingival bleeding, subgingival calculus, probing depth, clinical attachment level (CAL) and radiographic alveolar crestal height (ACH) was performed, and 8 putative bacterial pathogens from the subgingival flora measured. RESULTS: Reliability of subjects' responses and internal consistencies of all the subscales on the instruments used were high, with Cronbach's alpha ranging from 0.88 for financial strain to 0.99 for job strain, uplifts, and hassles. Logistic regression analysis indicated that, of all the daily strains investigated, only financial strain was significantly associated with greater attachment and alveolar bone loss (odds ratio, OR = 1.70, 95% CI = 1.09 to 2.65 and OR = 1.68, 95% CI = 1.20 to 2.37, respectively) after adjusting for age, gender, and cigarette smoking. When coping behaviors were evaluated, it was found that those with more financial strain who were high emotion-focused copers (a form of inadequate coping) had a higher risk of having more severe attachment loss (OR = 2.24, 95% CI = 1.15 to 4.38) and alveolar bone loss (OR = 1.91, 95% CI = 1.15 to 3.17) than those with low levels of financial strain within the same coping group, after adjustment for age, gender, and cigarette smoking. Similar results were found among the low problem-focused copers for AL (OR = 2.21, 95% CI = 1.11 to 4.38) and ACH (OR = 2.12, 95% CI = 1.28 to 3.51). However, subjects with high levels of financial strain who reported high levels of problem-based coping (considered adequate or good coping) had no more periodontal disease than those with low levels of financial strain, suggesting that the effects of stress on periodontal disease can be moderated by adequate coping behaviors. CONCLUSIONS: We find that psychosocial measures of stress associated with financial strain and distress manifest as depression, are significant risk indicators for more severe periodontal disease in adults in an age-adjusted model in which gender (male), smoking, diabetes mellitus, B. forsythus, and P. gingivalis are also significant risk indicators. Of considerable interest is the fact that adequate coping behaviors as evidenced by high levels of problem-based coping, may reduce the stress-associated risk. Further studies also are needed to help establish the time course of stress, distress, and inadequate coping with respect to the onset and progression of periodontal disease, and the mechanisms that explain this association.

Associations between oral conditions and respiratory disease in a national sample survey population.

Respiratory infectious diseases such as bacterial pneumonia and bronchitis are common and costly, especially in institutionalized and elderly inpatients. Respiratory infection is thought to rely in part on the aspiration of oropharyngeal flora into the lower respiratory tract and failure of host defense mechanisms to eliminate the contaminating bacteria, which then multiply to cause infection. It has been suggested that dental plaque may act as a reservoir of respiratory pathogens, especially in patients with periodontal disease. However, the impact of poor oral health on oral respiratory pathogen colonization and lung infection is uncertain, especially in ambulatory, non-institutionalized populations. To begin to assess potential associations between respiratory diseases and oral health, data from the National Health and Nutrition Examination Survey I (NHANES I) were analyzed. This database contains information on the general health status of 23,808 individual Of these, 386 individuals reported a suspected respiratory condition that was further assessed by a physician. These subjects were categorized as having a confirmed chronic respiratory disease (chronic bronchitis or emphysema) or an acute respiratory disease (influenza, pneumonia, acute bronchitis). They were compared to those not having a respiratory disease. Initial non-parametric analysis noted that individuals with a confirmed chronic respiratory disease (n = 41) had significantly greater oral hygiene index scores than subjects without respiratory disease (n = 193; P = 0.0441). Logistic regression analysis of data from these subjects, which considered age, race, gender, smoking status, and simplified oral hygiene index (OHI), suggested that subjects having the median OHI value were 1.3 times more likely to have a chronic respiratory disease relative to those with and OHI of O. Similarly, subjects with the maximum OHI value were 4.5 times more likely to have a chronic respiratory disease than those with an OHI of O. No evidence was found to support an association between the periodontal index and any respiratory disease. These results suggest OHI to have a residual effect on chronic respiratory disease of both practical and statistical significance.

Models to evaluate the role of stress in periodontal disease.

We evaluated the association of stress,distress, and coping behaviors with periodontal disease in 1,426 subjects, aged 25 to 74, in Erie County, NY, Demographic characteristics, medical and dental history, and tobacco and alcohol consumption, as well as clinical assessments of supragingival plaque, subgingival flora, gingival bleeding, calculus, probing depth, clinical attachment level (CAL), and radiographic alveolar bone loss (ABL) were obtained for each subject. Subjects also completed a set of 5 psychosocial instruments that measured life events, daily strains, hassles and uplifts, distress, and coping behaviors. Internal consistencies of all subscales on the instruments were high, with Cronbach's alpha ranging from 0.88 to 0.99. Logistic regression indicated that financial strain was significantly associated with greater attachment and alveolar bone loss (OR 1.70; 95% CI, 1.09-2.65; and 1.68; 95% CI, 1.20-2.37, respectively) after adjusting for age, gender, and smoking. When those with financial strain were stratified with respect to coping behaviors, it was found that those who exhibited high emotion-focused coping (inadequate coping) had and even higher risk of having more severe attachment loss (OR 2.24; 95% CI, 1.15-4.38) and alveolar bone loss (OR 1.91; 95% CI, 1.15-3.17) than those with low levels of financial strain within the same coping group, after adjustment for age, gender, and cigarette smoking. After further adjusting for number of visits to the dentist, those with financial strain who were high emotion-focused copers still had higher levels of periodontal disease based on CAL (OR 2.12; 95% CI, 1.07-4.18). In contrast, subjects with high levels of financial strain who reported high levels of problem-based coping (good coping) had no more periodontal disease than those with low levels of financial strain. Salivary cortisol levels were higher in a test group exhibiting severe periodontitis, a high level of financial strain, and high emotion-focused coping, as compared to a control group consisting of those with little or no periodontal disease, low financial strain, and low levels of emotion-focused coping (11.04 +/-4.4 vs/ 8.6 +/- 4.1 nmol/L salivary cortisol, respectively). These findings suggest that psychosocial measures of stress associated with financial strain are significant risk indicators for periodontal disease in adults. Further prospective studies are needed to help establish the time course of stress, distress, and inadequate coping on the onset and progression of periodontal disease, as well as to evaluate the mechanisms by which stress exerts its effects on periodontal infections.

Efficacy of a triclosan/NaF dentifrice in the control of plaque and gingivitis and concurrent oral microflora monitoring.

PURPOSE: To compare the effect of a dentifrice containing 0.3% triclosan and 1100 ppm fluoride and a control dentifrice containing 1100 ppm fluoride on plaque, gingiva and the oral microflora in a long-term study simulating clinical usage. MATERIALS AND METHODS: 159 subjects entered the clinical study and 80 were randomly selected to participate in the microbiological evaluation. 71 subjects completed the detailed evaluation of the oral microflora after 6 months use. Plaque was collected at baseline, 3 months, and 6 months, and examined by darkfield microscopy, Gram stain, immunofluorescence, and selective and non-selective media. Changes in antimicrobial susceptibilities were determined for the first 6-month period and for 6 months post-therapy for 68 subjects who completed the entire study. Susceptibilities of whole plaque samples and MIC values for two pre-designated common plaque organisms, A. viscosus and V. parvula were performed. RESULTS: Multivariate ANOVA and non-parametric analyses revealed no statistical differences for any factor tested. No detrimental shifts were found in either; (1) the compositional make up of the normal flora, (2) the periodontopathic or cariogenic flora, or (3) the opportunistic flora in either group of dentifrice users. Both treatments resulted in decreases in Gram positive cocci over time. There was a reduction in spirochetes in the triclosan/fluoride group as compared to the control group. No overgrowth in opportunists, periodontal pathogens, or cariogenic flora was found in either group. No increase in the proportion of the whole plaque flora resistant to triclosan was found nor was an increase in the MIC values of either A. viscosus or V. parvula in either group. Overall, there appeared to be a general decrease in plaque bacteria in both groups over the course of the experiment.

Reliability of a self-reported health questionnaire in a periodontal disease study.

This study assesses the reliability of a self-reported health questionnaire completed by 413 subjects aged 25-74 yr in the Erie County Periodontal Disease (ECPD) Study. Specific questions on general and oral health conditions were completed by each subject during a first visit and at a follow-up examination 2 yr later, and the two compared. Results showed that the overall measure of agreement between the two visits is substantial (average kappa, kappa = 0.80). Variation by gender and age were minimal. Questions regarding allergy to medications, oral treatment, reason for tooth extraction, health symptoms and history of systemic diseases exhibited high levels of agreement (kappa ranged from 0.71-0.90). Information on vitamin and mineral intake yielded kappa = 0.63. Oral conditions scored the lowest but were still acceptable (kappa = 0.57). These findings indicate that there were no significant discrepancies in self-reported responses to the health questionnaire used in the ECPD Study. Although the information provided by the subject may not be as accurate as compared to laboratory testing, it is nevertheless a reliable source of information which can be utilized cost-effectively in research studies.

Treatment of periodontal disease in diabetics reduces glycated hemoglobin.

Periodontal disease is a common infection-induced inflammatory disease among individuals suffering from diabetes mellitus. The purpose of this study was to assess the effects of treatment of periodontal disease on the level of metabolic control of diabetes. A total of 113 Native Americans (81 females and 32 males) suffering from periodontal disease and non-insulin dependent diabetes mellitus (NIDDM) were randomized into 5 treatment groups. Periodontal treatment included ultrasonic scaling and curettage combined with one of the following antimicrobial regimens: 1) topical water and systemic doxycycline, 100 mg for 2 weeks; 2) topical 0.12% chlorhexidine (CHX) and systemic doxycycline, 100 mg for 2 weeks; 3) topical povidone-iodine and systemic doxycycline, 100 mg for 2 weeks; 4) topical 0.12% CHX and placebo; and 5) topical water and placebo (control group). Assessments were performed prior to and at 3 and 6 months after treatment and included probing depth (PD), clinical attachment level (CAL), detection of Porphyromonas gingivalis in subgingival plaque and determination of serum glucose and glycated hemoglobin (HbA1c). After treatment all study groups showed clinical and microbial improvement. The doxycycline-treated groups showed the greatest reduction in probing depth and subgingival Porphyromonas gingivalis compared to the control group. In addition, all 3 groups receiving systemic doxycycline showed, at 3 months, significant reductions (P < or = 0.04) in mean HbA1c reaching nearly 10% from the pretreatment value. Effective treatment of periodontal infection and reduction of periodontal inflammation is associated with a reduction in level of glycated hemoglobin. Control of periodontal infections should thus be an important part of the overall management of diabetes mellitus patients.

Effect of mechanical treatment on healing after third molar extraction.

The aim of this study was to determine the effect of subgingival scaling and root planing on healing of the distal surface of second molars following extraction of third molars. Twenty-eight patients with contralateral erupted third molars and pocket depths greater than or equal to 3 mm on the distal surface of the second molars participated in this study. Measurements of supragingival bacterial plaque, bleeding on probing, pocket depth, and relative attachment level were performed at baseline and 2 months after treatment. Extraction of contralateral third molars was carried out simultaneously. The experimental site received thorough scaling and root planing of the distal surface of the second molar, while the control site received extraction alone. Experimental sites showed significant improvement in all clinical parameters assessed compared to the control sites. In conclusion, periodontal lesions on the distal of second molars can be significantly improved following scaling and root planing after extraction of third molars.

Pulmonary edema of scuba divers.

A syndrome of acute pulmonary edema has been previously reported among scuba divers in cold, European waters. Because of the temperatures involved, the name "cold-induced pulmonary edema" was coined in the original 1989 description. We report six individuals who developed the identical syndrome, five while diving in Puget Sound and one in the Gulf of Mexico. The four women and two men ranged in age from 24 to 60 yr. They experienced one to six episodes apiece, each with the development severe dyspnea at depth without excessive exertion. Associated symptoms included cough, weakness, expectoration of froth, chest discomfort, orthopnea, wheezing, hemoptysis, and dizziness. Emergency medical evaluation of four divers revealed rales on examination and pulmonary edema on chest radiograph. In one diver with pulmonary edema on chest radiograph, pulmonary capillary wedge pressure was normal when measured acutely. Symptoms resolved either spontaneously over 1-2 days or with standard medial treatment for pulmonary edema. Prior history of cardiovascular disease was negative except for hypertension and mitral valve prolapse in one diver. Cardiac evaluations following recovery from the acute episodes were normal. Episodes in the cold waters of Puget Sound sometimes occurred despite the use of dry suits. Furthermore, one diver developed recurrent episodes in 27 degrees C water off Cozumel, Mexico. Development of pulmonary edema while scuba diving constitutes a distinct clinical entity which may occur in either "cold" or "warm" water. It is not associated with a decompression mechanism. Personnel caring for divers should be aware of the syndrome in order to provide optimal medical management.

The role of osteopenia in oral bone loss and periodontal disease.

Osteoporosis and periodontitis are diseases which affect a large number of women and men, with incidence increasing with advancing age. Osteopenia is a reduction in bone mass due to an imbalance between bone resorption and formation, favoring resorption, resulting in demineralization and leading to osteoporosis. Osteoporosis is a disease characterized by low bone mass and fragility and a consequent increase in fracture risk. Periodontitis is characterized by inflammation of the supporting tissues of the teeth, resulting in resorption of the alveolar bone as well as loss of the soft tissue attachment to the tooth and is a major cause of tooth loss and edentulousness in adults. The relationship of osteopenia to oral bone loss and periodontal disease has been addressed in a limited number of studies. A review of current knowledge regarding this relationship is presented. Interpretation of the literature is complicated by the variety of methods used to assess osteopenia, oral bone mass, and periodontitis, as well as varying definitions of outcomes of interest. Results of a previously unpublished study are presented which suggest that severity of osteopenia is related to loss of alveolar crestal height and tooth loss in post-menopausal women. The literature on the relationship among these disorders is limited and points to the need for additional studies which thoroughly evaluate the influence of potential confounding factors to further define the relationship between low bone mineral density and periodontal disease in larger populations. Clearer understanding of this relationship may aid health care providers in their efforts to detect and prevent osteoporosis and periodontal disease. Increased dialogue among medical and dental professional will be increasingly important in achieving and maintaining patients' optimal health.

Sources of error for periodontal probing measurements.

This study determined the relative contribution to probing measurement reliability of several factors, compared with that of random error. Probing measurements were performed by examiners properly trained and calibrated. A total of 5771 pairs of replicate pocket depth (PD) and relative attachment level (RAL) measurements were performed with the Florida Probe. A total of 1488 replicate clinical attachment level (CAL) measurements were performed with the North Carolina 15 mm probe. In addition, longitudinal replicate measurements of RAL were performed at 0 and 12 months on 816 sites in 11 patients utilizing the Florida Probe 20 mm disk probe. Measurement reliability with the Florida Probe resulted in mean intraexaminer variances of 0.21 and 0.33, for PD and RAL, respectively (s.e.m. 0.46 mm for PD and 0.57 mm for RAL). Measurement reliability with the conventional probe resulted in mean intra-examiner variances of 0.19 for PD and 0.32 for CAL (s.e.m. 0.44 mm and 0.56 mm). Pocket depth contributed to = 5% of the variability of the intra-examiner variance with both probes with other contributing factors being the individual patient, tooth and site location. Mean intra-examiner reproducibility for duplicate RAL measurement performed at 0 and 12 months was 0.24 and 0.19, respectively (s.e.m. 0.49 mm and 0.43 mm). In conclusion, a mean intra-examiner variance of < or = 0.24 can be achieved for replicate measurements with both electronic and conventional probes for moderate and severe periodontitis patients. Individual examiner, individual patient and site location contribute up to 10% to the overall variance. Hence, the pattern of variability for intra-examiner variance of probing measurements performed with either electronic or conventional probes by trained and calibrated examiners is mostly random error.

The natural history of periodontal disease. The correlation of selected microbiological parameters with disease severity in Sri Lankan tea workers.

The purpose of this study was to assess the prevalence of A. actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, and their association with periodontal disease states in a population sample from Sri Lanka. Based on clinical parameters, a total of 536 sites in 268 male Sri Lankan tea workers were categorized as healthy, or showing gingivitis only, moderate or advanced periodontitis. Bacterial samples were obtained from all sites and the three target bacteria identified by indirect immunofluorescence. P. intermedia, P. gingivalis and A. actinomycetemcomitans were found in 76%, 40% and 15% of the subjects, respectively. Of the 536 periodontal sites, 10.5% were categorized with "no disease", 14% "gingivitis only": 59% with moderate and 16% with advanced periodontitis. The prevalence of P. gingivalis and P. intermedia was significantly higher in sites with moderate and advanced periodontitis than in sites with no disease or gingivitis only. A. actinomycetemcomitans was not found in healthy sites, but occurred with equal frequency in sites with gingivitis, moderate and advanced periodontitis. The association between these three bacteria and periodontal diseases in Sri Lankan tea laborers was similar to that described for other non-industrialized and industrialized countries.

Microbial alterations in supragingival dental plaque in response to a triclosan-containing dentifrice.

A total of 325 subjects were entered into a double-blind, stratified 2-treatment clinical study that examined the effects of a dentifrice containing 0.3% triclosan, 2% Gantrez copolymer and 0.243% sodium fluoride on supragingival dental plaque and gingivitis. A subset of 159 subjects including 72 men and 87 women participated in the microbiological component of this study, which was designed to detect shifts in supragingival bacterial species in response to triclosan. Subjects were divided into two groups: one performed normal oral hygiene with the triclosan/copolymer dentifrice and a control group used a placebo dentifrice without triclosan. At baseline, 3 and 6 months during treatment and at 6, 12, 18 and 24 weeks post-treatment, supragingival dental plaque was collected from the buccal and lingual surfaces of the 4 first molar teeth and assayed for: 1) bacterial morphotypes by phase-contrast microscopy; 2) select bacterial groups and bacterial species by culture; and 3) target periodontal pathogens including Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis and Prevotella intermedia by immunofluorescence microscopy. There were few statistically significant differences between treatment groups in any of the 90 microbiological parameters measured at the 7 different time points. The control group demonstrated significantly higher levels of cultivable Neisseria and higher proportions at the 3-month treatment period of P. gingivalis-infected subjects and mean cells. After 6 months of treatment, the triclosan group demonstrated higher levels of fusiforms. Analysis of triclosan resistance data failed to detect a shift towards increased proportions of bacteria resistant to triclosan, and both treatment groups demonstrated triclosan-resistant strains, predominantly Veillonella dispar. This study confirms the microbiological safety of triclosan-containing dentifrices and suggests that continued use can be associated with beneficial alterations in the bacterial composition of supragingival dental plaque.

Selection criteria utilized for hyperbaric oxygen treatment of carbon monoxide poisoning.

Medical directors of North American hyperbaric oxygen (HBO) facilities were surveyed to assess selection criteria applied for treatment of acute carbon monoxide (CO) poisoning within the hyperbaric medicine community. Responses were received from 85% of the 208 facilities in the United States and Canada. Among responders, 89 monoplace and 58 multiplace chamber facilities treat acute CO poisoning, managing a total of 2,636 patients in 1992. A significant majority of facilities treat CO-exposed patients with coma (98%), transient loss of consciousness (LOC) (77%), ischemic changes on electrocardiogram (91%), focal neurologic deficits (94%), or abnormal psychometric testing (91%), regardless of carboxyhemoglobin (COHb) level. Although 92% would use HBO for a patient presenting with headache, nausea, and COHb 40%, only 62% of facilities utilize a specified minimum COHb level as the sole criterion for HBO therapy of an asymptomatic patient. When COHb is used as an independent criterion to determine HBO treatment, the level utilized varies widely between institutions. Half of responding facilities place limits on the delay to treatment for patients with only transient LOC. Time limits are applied less often in cases with persistent neurologic deficits. While variability exists, majority opinions can be derived for many patient selection criteria regarding the use of HBO in acute CO poisoning.

Self-efficacy and confidence in outcomes as determinants of self-care practices in inner-city, African-American women with non-insulin-dependent diabetes.

The purpose of this study was to examine the extent to which perceived self-efficacy and confidence in outcomes, selected demographic variables, and disease characteristics (age, duration of diabetes, presence of documented complications) affect an individual's adherence over time to a diabetes regimen of home glucose testing, medication/insulin administration, diet, and exercise. A convenience sample of 118 inner-city, African-American women with type II, non-insulin-dependent diabetes mellitus receiving outpatient care at a large urban hospital were asked to complete measures of each of the psychosocial variables on two occasions, separated by an interval of 4 to 5 months, and coinciding with their next scheduled clinic visit. Bivariate and multivariate analyses at Times 1 and 2 demonstrated the ability of self-efficacy alone to explain diet, exercise, and home-testing behaviors while suggesting variability within individuals in sense of self-efficacy over time.