Biomedical subjects

G Flowerdew

Publications and source records attributed to G Flowerdew.

At least 19 recordsLinked to original sources

PubMed2006

Rates of urinary tract injury from gynecologic surgery and the role of intraoperative cystoscopy.

OBJECTIVE: To estimate the rates of urinary tract injury after benign gynecologic surgery. To explore the role of routine intraoperative cystoscopy at benign gynecologic surgery. DATA SOURCES: We conducted a systematic MEDLINE search for urinary tract injuries at gynecologic surgery for the period from November 1998 to May 2004 and combined this with a previous systematic review performed in the same fashion for the period from January 1966 to October 1998. METHODS OF STUDY SELECTION: There were 47 studies that fit our inclusion criteria: 29 that did not use routine intraoperative cystoscopy, 17 that used routine intraoperative cystoscopy, and 1 that reported the frequency of urinary tract injury separately, with and without routine intraoperative cystoscopy. We determined the crude and fitted ureteric and bladder injury rates for each surgery type from the studies where routine intraoperative cystoscopy was not performed and then from the studies where routine intraoperative cystoscopy was performed. TABULATION, INTEGRATION, AND RESULTS: From studies without routine cystoscopy, combined ureter and bladder injury rates varied according to the complexity of the surgery, ranging from less than 1 injury per 1000 for subtotal hysterectomy with or without bilateral salpingo-oophorectomy to as many as 13 injuries per 1000 surgeries for laparoscopic hysterectomy with or without bilateral salpingo-oophorectomy and for other gynecologic and urogynecologic surgeries. Injury rates were higher when routine intraoperative cystoscopy was used, but the confidence intervals were wider. CONCLUSION: The reasons for higher injury detection rates when routine cystoscopy was performed are unclear. Further study is needed to identify the scenarios where routine cystoscopy is warranted after major gynecologic surgery.

Cystoscopy↗

PubMed2001

A comparative evaluation of waist circumference, waist-to-hip ratio and body mass index as indicators of cardiovascular risk factors. The Canadian Heart Health Surveys.

OBJECTIVE: To comparatively evaluate cut-off points of waist circumference, body mass index and waist to hip ratio with respect to their ability to predict other individual and multiple cardiovascular disease risk factors. DESIGN: Population-based, cross-sectional surveys. SUBJECTS: A total of 9913 men and women aged 18-74, selected using health insurance registries from five Canadian provinces. MEASUREMENTS: Anthropometric measures, other cardiovascular risk factors, receiver operating characteristic curves, sensitivity, specificity, positive and negative predictive values. RESULTS: : Waist circumference may be the best single indicator of other individual and multiple cardiovascular risk factors. Optimal cut-off points of all anthropometric measures are dependent on age, sex and the prevalence of the risk factor(s) being considered. For waist circumference, cut-off points of > or =90 cm in men and > or =80 cm in women may be most appropriate for prediction of individual and multiple risk factors in Caucasian populations. CONCLUSION: Health professionals should incorporate the use of waist circumference measurements in their routine clinical examination of adult patients.

Adolescent↗

PubMed2001

Performance of a commercial immunoassay for detection and differentiation of periodontal marker bacteria: analysis of immunochemical performance with clinical samples.

BACKGROUND: We employed a commercial immunoassay for simultaneous detection and differentiation of marker bacteria Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia and reassessed the immunochemical performance of the assay. METHODS: We compared the analytical performance of the immunoassay in our study of clinical samples from 249 periodontal patients in 2 private periodontal practices with the previously reported analytical performance of the same immunoassay. We also compared immunoassay measurements of the marker bacteria in clinical samples with values obtained in other studies by direct culture of the same organisms. RESULTS: The assay produced 3 times more high-end readings than reported previously. We also reassessed and revised previously published calibration curves for the immunoassay. The immunoassay provided measurements of the marker bacteria in clinical samples from our patients that were comparable to and consistent with measurements of the same bacteria by direct culture in other studies. CONCLUSIONS: We ascribe the increased sensitivity of the immunoassay in our study to: 1) a more standardized and vigorous sample dispersion that improves release of particulate and soluble antigens from dental plaque biofilm, and 2) better visualization of the reaction product of the enzyme-linked immunoassay. High-technology assays, such as diagnostic immunoassays, have a significant potential for future development in dental diagnosis, because they simplify detection and measurement of biologically important markers such as specific bacteria in clinical samples. Commercial assays also have an important potential for standardization of clinical measurements of biological markers.

Aggregatibacter actinomycetemcomitans↗

PubMed2001

Effects of smoking and treatment status on periodontal bacteria: evidence that smoking influences control of periodontal bacteria at the mucosal surface of the gingival crevice.

BACKGROUND: We examined whether smoking status could influence growth of potentially pathogenic bacteria in the periodontal environment of treated and untreated periodontal patients. METHODS: We have previously reported effects of treatment status on marker bacteria in our patients. We established a history of any smoking during 6 months prior to microbiological sampling (F-ME, 16 smokers out of 64; MHM, 70 smokers out of 185). We used a commercial immunoassay to quantitate Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans in paper point samples from periodontal sites. RESULTS: Logistic regression showed that in smokers, neither P. gingivalis nor A. actinomycetemcomitans was quantitatively increased, while P intermedia was somewhat increased. Multiple regression demonstrated that smoking disrupts the positive relationship between increasing probing depth and increasing bacterial growth that is found in non-smokers. In smokers, growth of marker bacteria at shallow sites (< or =5 mm) was significantly increased to the levels found at deeper sites (>5 mm) in both smokers and non-smokers. Supragingival plaque biofilm was identified as a reservoir for marker bacteria; smokers and nonsmokers had equal ranges of oral cleanliness. CONCLUSIONS: Smoking-associated periodontitis is not simply a reflection of oral cleanliness. Smoking extends a favorable habitat for bacteria such as P. gingivalis, P. intermedia, and A. actinomycetemcomitans to shallow sites (< or =5 mm). Molecular byproducts of smoking interfere with mechanisms that normally contain growth of damaging bacteria at the surface of the oral mucosa in gingival crevices. In this way, smoking can promote early development of periodontal lesions.

Adult↗

PubMed2001

Physician characteristics in relation to cardiovascular drugs commonly prescribed for hypertension in Nova Scotia.

BACKGROUND: Cardiovascular drugs are the most frequently prescribed class of drugs in Canada. Among them, drugs used to treat hypertension are the single largest component. Variability in how these drugs are prescribed should be based on the specific characteristics of patients. However, some evidence shows that physician characteristics can also play a substantial role in prescribing trends. Such variation is also associated with varying beneficial and adverse patient outcomes. PURPOSE: To determine whether prescribing patterns of drugs used to treat hypertension in elderly patients in Nova Scotia varied by physician characteristics. METHODS: A retrospective, population-based descriptive study was done using the Nova Scotia Pharmacare program data for the fiscal year 1995/96. The unit of analysis was the individual physician. All drugs indicated in the management of hypertension were included for the analysis. RESULTS: Of 1466 physicians included in the analysis, 1004 were family physicians (FPs) and/or general practitioners (GPs), 155 were internal medicine specialists and 307 were other specialists. Fifty-eight per cent of 103,193 eligible senior citizens received at least one of the study medications. FPs and/or GPs prescribed 95.9% of all the study drugs. Internists prescribed proportionately fewer angiotensin-converting enzyme inhibitors, thiazides and other diuretics compared with the FPs and/or GPs but more beta-blockers and calcium channel blockers. A large proportion of the FPs and/or GPs (55.3%) prescribed less than 10% of the total day's supply of drugs, whereas a small proportion of FPs and/or GPs (16.3%) prescribed 52.6% of all the study drugs. There was no variation in the distribution of the types of antihypertensives prescribed based on physician age, sex or volume of prescribing. A slight variation in prescribing was seen with location of practice. CONCLUSIONS: Patterns of prescribing cardiovascular drugs used to treat hypertension were remarkably unaffected by physician characteristics. This finding counters other evidence in the literature that has raised concerns over prescribing patterns of certain types of physicians. Prescribing patterns may vary for other drug classes, but for this group of antihypertensives, little variability was found.

Adult↗

PubMed2000

Management of patients with suspected deep vein thrombosis in the emergency department: combining use of a clinical diagnosis model with D-dimer testing.

The management of patients presenting to hospital Emergency Departments with suspected deep vein thrombosis is problematic since urgent diagnostic imaging is at times unavailable. We evaluated the accuracy of a rapidly available D-dimer test and the potential of combining D-dimer testing with an explicit clinical model to improve the management of patients with suspected deep vein thrombosis. Two hundred and fourteen patients with suspected deep vein thrombosis presenting to the Emergency Departments of two tertiary care institutions were enrolled in this prospective cohort study. Patients were evaluated by an Emergency Physician who determined the pre-test probability for deep vein thrombosis to be either low, moderate, or high using an explicit clinical model. Patients were managed according to their pre-test probability category by specific algorithms that in all cases included venous ultrasound imaging within 24 h and a 90-day follow-up for the development of thromboembolic complications. Patients also underwent fingerstick SimpliRED(R) whole blood agglutination D-dimer testing; however, D-dimer results did not influence subsequent patient management. D-dimer had a sensitivity of 82.5% and a specificity of 84.9% for the diagnosis of deep vein thrombosis. The observed negative predictive value of D-dimer was 96.9% (95% CI, 93.0% to 99.1%) overall, and 100% (95% CI, 96.3% to 100%) in low probability patients, 94.1% (95% CI, 83.8% to 98.8%) in moderate probability patients, and 86.7% (95% CI, 59.4% to 98.3%) in high probability patients. SimpliRED(R) D-dimer has a high negative predictive value and may be useful in excluding the diagnosis in patients at low pre-test probability for deep vein thrombosis.

Agglutination Tests↗

PubMed1999

Thrombosis in the emergency department: use of a clinical diagnosis model to safely avoid the need for urgent radiological investigation.

CONTEXT: The management of patients presenting to hospital emergency departments with suspected deep vein thrombosis (DVT) is problematic because urgent diagnostic imaging capability is sometimes unavailable. Experienced physicians using clinical skills alone can classify patients with suspected DVT into low-, moderate-, and high-probability categories. OBJECTIVES: To determine the accuracy of an explicit clinical model for the diagnosis of DVT when applied by emergency department physicians and to assess the safety and feasibility of a management strategy based on the clinical pretest probability for patients presenting to the emergency department with suspected DVT outside of regular hospital staff work hours. METHODS: A prospective cohort study was performed in the emergency departments of 2 tertiary care institutions involving 344 patients with suspected DVT. Patient conditions were evaluated by an emergency department physician who determined the pretest probability for DVT to be low, moderate, or high using an explicit clinical model. Patients for whom DVT was considered a low pretest probability were discharged from the emergency department and returned the following day for venous compression ultrasound imaging of the affected leg. Patients for whom DVT was considered a moderate pre-test probability received a single, weight-adjusted dose of subcutaneous unfractionated heparin sodium (between 12 500 and 20 000 U), were discharged from the emergency department, and returned the next morning to undergo ultrasonography. Patients for whom DVT was considered a high pretest probability were admitted to the hospital, administered intravenous unfractionated heparin, and ultrasonography was arranged within 24 hours. Patients with positive ultrasonographic findings were diagnosed with DVT, except for those with low pretest probability for whom confirmatory venography was performed. Patients with DVT excluded in the initial evaluation period did not receive anticoagulant therapy. All patients were followed up for 90 days to monitor development of thromboembolic or bleeding complications. RESULTS: Twenty-four (49.0% [95% confidence interval (CI), 34.5%-63.6%]) of 49 patients in the high-probability category, 15 (14.3% [95% CI, 8.3%-22.4%]) of 105 in the moderate-, and 6 (3.2% [95% CI, 1.2%-6.7%]) of 190 in the low-probability category were confirmed to have DVT. Overall, 45 (13.1%) of 344 patients were confirmed to have DVT. No patient developed pulmonary embolism or major bleeding complications within 48 hours of initial evaluation in the emergency department. Of the 301 patients who had DVT excluded during the initial evaluation period, only 2 (0.7% [95% CI, 0.1%-2.3%]) developed venous thromboembolic complications (calf vein thromboses in both) in the 3-month follow-up period. CONCLUSIONS: Using an explicit clinical model, emergency department physicians can accurately classify patients with suspected DVT into high-, moderate-, and low-probability groups. A management plan based on probability for DVT that avoids the need for urgent diagnostic imaging is safe and feasible in the emergency department setting.

Decision Trees↗

PubMed1998

Diagnostic utility of specific microbiological markers for periodontal diseases.

Specific detection of marker organisms Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans with an immunoassay provided 2 types of useful information directly into private clinical practice: 1) persistence of P. gingivalis in patients undergoing regular treatment allowed rapid identification of pockets requiring further treatment without waiting for measurable progression of lesions and 2) presence of A. actinomycetemcomitans in adults at any stage of diagnosis or treatment identified patients who may prove to have difficult-to-manage periodontitis. We made these findings in 253 patients (234 in specialist periodontal practices [F-ME 55; MHM 179] and 19 in general dental practice [EWM]). The search for useful diagnostic markers overlaps only partly with the search for periodontal pathogens. The P. gingivalis marker and the A. actinomycetemcomitans marker identify 2 different patterns of infection that appear to reflect 2 different underlying problems. Demonstration of pocket-dependent infection with P. gingivalis in treated patients provides an outcome marker for sites not converting to marker-negative sites at detection levels of the immunoassay. This information facilitates selection of sites and patients requiring adjustment of treatment regimens. Detection of A. actinomycetemcomitans in adult patients is significantly associated with periodontitis characterized as refractory. Positive identification of A. actinomycetemcomitans with the immunoassay supports clinical decision-making by drawing attention to adult patients who require closer monitoring and intensive persistent treatment. Successful application of immunoassay detection of microbiological markers is based on continuous patient monitoring to support clinical decisions; it does not replace careful clinical judgment.

Actinobacillus Infections↗

PubMed1998

Periodontitis-associated marker bacteria in an urban North American patient population: application of a commercial immunoassay.

We used an immunoassay to demonstrate marker organisms (Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans) in 3 private practice populations (F-ME periodontist, 55 patients; MHM periodontist, 179 patients; and EWM general dentist, 19 patients). Occurrence of the marker organisms involves the whole oral environment, not just individual sites, as shown by close correlation between presence of the marker organisms in 2 independent sites/samples within a single mouth. Presence of the marker P. gingivalis (and P. intermedia) relates closely to periodontal pocketing while presence of A. actinomycetemcomitans does not have this pocket-associated characteristic. There was no significant relationship between presence of the marker organisms and the number of teeth in a mouth, and in the periodontal practice patients there was no significant effect of gender on occurrence of the marker organisms. A. actinomycetemcomitans and the other 2 markers were found over the entire age range (12 to 75) of our patients. Regular periodontal treatment reduced occurrence of all marker organisms and increased the frequency of marker-negative patients and sites. Occurrence of the marker organisms above immunoassay threshold levels appears to represent how receptive a patient is to each individual organism. Most patients appear receptive to the presence of P. intermedia whether treated or not. Significantly fewer patients who underwent regular treatment show the presence of P. gingivalis or A. actinomycetemcomitans when compared to untreated patients. Diagnostic application of microbial markers requires ongoing clinical assessment of patients and careful clinical judgment. 1391.

Adolescent↗

PubMed1997

A simplified protocol for pessary management.

OBJECTIVE: To evaluate a simplified protocol for pessary management. METHODS: Women with symptomatic pelvic organ prolapse who opted for pessaries were enrolled in a prospective simplified protocol for pessary management. After the initial pessary fitting, they were seen at 2 weeks for reexamination and thereafter at 3- to 6-month intervals. RESULTS: One hundred ten women (mean age 65 years) were enrolled, and 81 (74%) of them were fitted successfully with a pessary. Life-table analysis showed that 66% of those who used a pessary for more than 1 month were still users after 12 months and 53% were still users after 36 months. The severity of pelvic prolapse did not predict the likelihood of pessary failure except in cases of complete vaginal eversion. Patients complaining of stress incontinence were less likely to have a successful pessary fitting and more likely to opt for surgery. Current hormone use and substantial perineal support do not predict greater likelihood of pessary fitting success. No serious complications from using the pessary were observed in the study sample. CONCLUSION: Stringent guidelines calling for frequent pelvic examinations during pessary use can be relaxed safely. Pessaries can be offered as a safe long-term option for the management of pelvic prolapse.

Adult↗

PubMed1996

Endometrial biopsy in DUB.

OBJECTIVE: To determine the incidence of abnormal endometrial histology in women with dysfunctional uterine bleeding and to evaluate the predictive value of risk factors for endometrial cancer in women with dysfunctional uterine bleeding (DUB). STUDY DESIGN: We conducted a retrospective review of 310 women with DUB who underwent endometrial biopsy. The risk factors for abnormal endometrial histology included menstrual cycle irregularity, diabetes, nulliparity, hypertension, weight > or = 100 kg and age > or = 40 years. The incidence of endometrial abnormalities was determined, and the predictive value of combinations of risk factors was assessed using stepwise logistic regression. RESULTS: Twenty-one patients (6.7%) had abnormal endometrial biopsies. Menstrual cycle irregularity (P = .0001), age > or = 40 years (p = .022) and hypertension (P = .058) were independently significant risk factors for abnormal endometrial histology. The probability of abnormal endometrial histology in a premenopausal woman with DUB whose cycle was regular was < 1%. The presence of menstrual cycle irregularity increased the probability of abnormal endometrial histology to 14.3%. CONCLUSION: The patient who presents with DUB and a history of menstrual cycle irregularity warrants an endometrial biopsy, regardless of age. The current clinical emphasis on age (especially > or = 40 years) as justification for endometrial biopsy is unwarranted in patients with DUB. More careful selection of patients for endometrial biopsy will mean that fewer women are unnecessarily exposed to the discomfort and risk of complications associated with endometrial biopsy.

Adolescent↗

PubMed1995

A simple model for predicting postoperative delirium in older patients undergoing elective orthopedic surgery.

OBJECTIVE: To determine the incidence, and severity of postoperative delirium (POD) in older patients undergoing elective orthopedic procedures and to identify potential preoperative risk factors. DESIGN: A prospectively studied cohort of elective orthopedic surgery patients. SETTING: A University teaching hospital. PATIENTS: Eighty patients who attended a preadmission clinic and, subsequently, underwent elective orthopedic surgery. All patients were aged 60 years or older, and all spoke English. MEASUREMENTS: Patients underwent preoperative medical, cognitive, and activities of daily living assessment with standardized instruments and were followed postoperatively with daily visits, telephone interviews with attending nurses using a modified confusion assessment model (CAM), and repeated cognitive testing. Suspected delirium was verified by direct physician assessment. RESULTS: The elective group had 14 (17.5%) cases of POD, of which six (7.5%) were severe. These incidences are low compared with those of nonelective surgery groups reported elsewhere in the literature. Stepwise multiple logistic regression identified two POD risk factors: clock-drawing scores < or = 6 (OR = 9.0, CI, 2.8 to 45.6) and male gender (OR = 5.6, CI 1.9 to 33.8). CONCLUSION: A simple model using clock-drawing scores and male gender for preoperative identification of elective patients at greatest risk for POD appears sensitive, predictive, and practical for the preadmission clinic setting, but it should be validated in a prospective trial.

Aged↗

PubMed1993

Use of ultrasound in a study of schistosomal periportal fibrosis in rural Zimbabwe.

Ultrasound was used to diagnose periportal fibrosis (PPF) in a rural Zimbabwean community where Schistosoma mansoni is endemic. Ultrasound findings were compared with stool microscopy and abdominal palpation in 492 adults (305 females). 47 (9.6%) had definite PPF. The prevalence of PPF increased with age (P < 0.001), while S. mansoni egg counts decreased with age. Even within age groups, egg count did not correlate with PPF. No association was found between lifetime alcohol consumption and the presence of PPF. Splenomegaly and mid-line enlargement of the liver were specific (97% and 94%) but insensitive (21% and 28%) markers for PPF. Spleen size varied with S. mansoni egg count independently of the presence or degree of PPF. Endoscopy of 18 patients with PPF revealed oesophageal varices in two, both of whom had severe PPF.

Abdomen↗

PubMed1993

Serum albumin in patients on continuous ambulatory peritoneal dialysis--predictors and correlations with outcomes.

Serum albumin (SA) is a powerful predictor of patient morbidity and mortality in hemodialysis, but data are limited for continuous ambulatory peritoneal dialysis (CAPD). SA was monitored in 76 new CAPD patients over 222 6-month periods and mean SA was correlated with morbidity and mortality during those periods. The influence of initial SA on duration of technique survival was also investigated. To determine which factors best predict SA, correlations with patient demographics and with 6-month measurements of dialytic dose, protein intake, and peritoneal transport were sought. Mean SA overall was 34.1 +/- 3.3 g/L, and mean initial SA was 33.4 +/- 3.1 g/L. Mean SA was lower in diabetics and in those aged 65 or over. Mean SA tended to increase during the first year on CAPD, and this increase was maintained, except in patients aged 65 or over, where it tended to revert to initial values. SA correlated with hospital days (r = -0.20; P < 0.005), fatigue index (r = -0.20; P < 0.005), nerve conduction (P < 0.001), and a variety of laboratory values, and lower SA was associated with technique failure (P < 0.03) and death (P < 0.07). Initial, as well as ongoing, SA was predictive of technique failure (P < 0.05) and Cox proportional hazards regression showed that this predictive power was independent of age, sex, diabetes, and other factors (P = 0.05). The strongest predictors of low SA by stepwise multiple regression were diabetes, a higher dialysate-to-plasma creatinine equilibration ratio, older age, lower body weight, and shorter time on CAPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

The fluoridation of drinking water and hip fracture hospitalization rates in two Canadian communities.

OBJECTIVES: The purpose of this study was to compare hip fracture hospitalization rates between a fluoridated and a non-fluoridated community in Alberta, Canada: Edmonton, which has had fluoridated drinking water since 1967, and Calgary, which considered fluoridation in 1991 but is currently revising this decision. METHODS: Case subjects were all individuals aged 45 years or older residing in Edmonton or Calgary who were admitted to hospitals in Alberta between January 1, 1981, and December 31, 1987, and who had a discharge diagnosis of hip fracture. Edmonton rates were compared with Calgary rates, with adjustment for age and sex using the Edmonton population as a standard. RESULTS: The hip fracture hospitalization rate for Edmonton from 1981 through 1987 was 2.77 per 1000 person-years. The age-sex standardized rate for Calgary was 2.78 per 1000 person-years. No statistically significant difference was observed in the overall rate, and only minor differences were observed within age and sex subgroups, with the Edmonton rates being higher in males. CONCLUSIONS: These findings suggest that fluoridation of drinking water has no impact, neither beneficial nor deleterious, on the risk of hip fracture.

Aged↗

PubMed1992

Cranial computed tomographic observations in multi-infarct dementia. A controlled study.

BACKGROUND AND PURPOSE: We compared cranial computed tomography findings among 58 multi-infarct dementia index cases and 74 multi-infarct control subjects without cognitive impairment to identify potential determinants of multi-infarct dementia. METHODS: The cranial computed tomography records of acute ischemic stroke patients with a history of multiple cerebral infarcts were compared to determine the number, location, and size of cerebral infarcts; the pattern of infarction; brain volume loss; and the degree of white matter lucency, sulcal enlargement, and ventricular enlargement. Multi-infarct patients were divided into two groups: 1) index cases were defined as those with multi-infarct dementia as defined by the Diagnostic and Statistical Manual of Mental Disorders, edition 3 (DSM-III) criteria; and 2) control subjects were defined as those multi-infarct patients without dementia or multi-infarct dementia according to DSM-III criteria. RESULTS: Overall, multi-infarct index cases had more cerebral infarcts, more cortical and subcortical left hemisphere infarcts, higher mean ventricular volume to brain volume ratio, more extensive enlargement of the body of the lateral ventricles and cortical sulci, and a higher prevalence of white matter lucencies. Among multi-infarct cases and control subjects the most frequent site of infarction was the subcortical region, and the most frequent pattern of infarction was lacunar. Stepwise logistic regression analysis examined cranial computed tomography as well as other factors and showed that level of education, stroke severity, left cortical infarction, and diffuse enlargement of the left lateral ventricle were the best overall predictors of multi-infarct dementia. CONCLUSIONS: Level of education, stroke severity, and left hemisphere infarction may be predictors of multi-infarct dementia.

Brain↗

PubMed1992

Effect of gum chewing on the pH of dental plaque.

Saliva stimulation by gum chewing has been reported to neutralize plaque acidity. We compared the plaque pH response to bread with honey followed by sucrose-or sorbitol-sweetened gum chewing for 20 minutes. Bread and honey was chosen as previous work in our laboratory found this a worst case challenge in terms of the extent and duration of the pH decline. The study design was factorial with: 4 subjects x 2 replicates x 3 treatments. Each subject received each of the 3 treatments: food (bread and honey), food followed by sorbitol chewing gum, and food followed by sucrose chewing gum. Subjects accumulated plaque for 3 days on a partial prosthesis with a glass electrode set in the approximal space in the gap left by a missing first molar. Plaque pH was monitored for 150 min: baseline (0-10), food (11-30), +/- gum chewing (31-50), post-chew monitoring (51-150). ANOVA of mean plaque pH showed no difference between treatments at baseline. Significantly higher pH levels (p < 0.01) were shown with both gums compared to no gum during the chew and post-chew phases. Plaque pH data were also converted to absolute acid values (cH). Food alone produced 1703 mumol/min.; food followed by sorbitol chewing gum produced 53 mumol/min.; and food followed by sucrose gum produced 156 mumol/min. While the post-chew pH curves were not identical for sucrose vs. sorbitol chewing gums, both neutralized plaque acidity, probably due to the induced salivary action.

Adult↗

PubMed1991

Cesarean sections in Alberta from April 1979 to March 1988.

OBJECTIVES: To determine (a) trends in the cesarean section rate in Alberta from April 1979 to March 1988, (b) the contribution of different primary indications to the overall increase in the cesarean section rate and (c) trends in the cesarean section rate by residence of the mother. DESIGN: Retrospective study. PARTICIPANTS: Women who gave birth in acute care hospitals in Alberta during the study period. Indications for cesarean section were defined by a hierarchic classification system. Geographic regions were identified according to the mother's residence. MAIN RESULTS: The crude cesarean section rate increased from 13.2 to 17.3 per 100 deliveries between 1979-80 and 1987-88. Previous cesarean section accounted for 54% of the increase, breech presentation for 17%, fetal distress for 17% and dystocia for 10%. The contribution of previous cesarean section was due to the substantial increase in the number of women presenting with a previous cesarean section. The cesarean section rate among women who had previously had the procedure decreased from 96.7% in 1979-80 to 84.6% in 1987-88. The crude cesarean section rates by region varied from 10.3 to 22.3 per 100 deliveries. CONCLUSIONS: Further efforts to reduce the rate of cesarean section among women who have previously undergone the procedure are needed to control the rate of cesarean section in Alberta. Decreasing the rate of primary cesarean section is also an important goal.

Adult↗