Biomedical subjects

R G Marks

Publications and source records attributed to R G Marks.

At least 19 recordsLinked to original sources

PubMed2004

The future of web-based clinical research in dentistry.

Clinical research is a growing industry in dentistry, requiring more efficient methods for research conduct. The Internet provides an opportunity for investigators to expand, enhance, and potentially redefine the way they conduct clinical research. A prime area for improved research is in clinical trials processes, due to their current high cost and inefficiencies. The Web offers the advantages of both centralization of information and coordination of multiple clinical trials processes. The result is improvements for the investigator sites, the sponsor, and subject safety. Observational studies also provide the opportunity for investigators to collect greater amounts of information in a more realistic dental environment. The Internet offers investigators the opportunity to collect outcomes information from sources worldwide, and more efficiently, accurately, and quickly, providing new valuable research answers. The tremendous explosion of genetic and gene therapy research will substantially increase the need for research methods that can manage the vast amount of complex new data, depending on the Internet to manage these research needs. The Internet holds promise for improving dental clinical research through its gains in efficiency, accuracy, and safety.

Clinical Trials as Topic↗

PubMed1998

Rationale and design of the International Verapamil SR/Trandolapril Study (INVEST): an Internet-based randomized trial in coronary artery disease patients with hypertension.

OBJECTIVES: The primary objective of the International Verapamil SR/Trandolapril Study (INVEST) is to compare the risk for adverse outcomes (all-cause mortality, nonfatal myocardial infarction [MI] or nonfatal stroke) in hypertensive patients with coronary artery disease (CAD) treated with either a calcium antagonist-based or a noncalcium antagonist-based strategy. BACKGROUND: Treatment recommendations for hypertension include initial therapy with a diuretic or beta-adrenergic blocking agent, for which reductions in morbidity and mortality are documented from randomized trials but are less than expected from epidemiologic data. For this reason, recent attention has focused on calcium antagonists or angiotensin-converting enzyme inhibitors. While these agents reduce blood pressure, outcome data from large randomized trials are lacking, but some case-control data, dominated by short-acting dihydropyridines, suggest an increased risk of cardiovascular events. These studies had methodologic limitations and did not differentiate among calcium antagonist types and formulations. Several studies differentiating among calcium antagonist types and an overview of published randomized trials show no increased risk with verapamil and suggestion for benefit in CAD patients. METHODS: A total of 27,000 CAD patients with hypertension will be randomized at 1,500 primary care sites to receive either a calcium antagonist-based (verapamil) or beta-blocker/diuretic-based (atenolol/hydrochlorothiazide) antihypertensive care strategy. The study uses a novel, electronic "paper-less" system for direct on-screen data entry, randomization and drug distribution from a mail pharmacy linked to the coordination center via the Internet. RESULTS: Contract negotiations with the United States and international sites are ongoing. Patients being enrolled are predominantly elderly (72% aged 60 years or older) men (54%), with either an abnormal coronary angiogram or prior MI (71%). In addition to hypertension, CAD and elderly age, most patients (89%) have one or more associated conditions (diabetes, dyslipidemia, smoking, cerebral or peripheral vascular disease, etc.) contributing to increased risk for adverse outcome. While 26% have diabetes, most of these are noninsulin dependent. Using the protocol strategies, target blood pressures (according to JNC VI) have been reached in 58% at the fourth visit, and as expected most (89%) are requiring multiple antihypertensive drugs. CONCLUSION: The design and baseline characteristics of the initial patients recruited for a prospective, randomized, international, multicenter study comparing two therapeutic strategies to control hypertension in CAD patients are described.

Aged↗

PubMed1998

Velopharyngeal function for speech after the Frolova primary palatoplasty technique.

OBJECTIVE: This study was undertaken by several members of the University of Florida Craniofacial Center to assess the results of palatoplasty performed by the method devised by Larisa Y. Frolova, M.D. in 1971. DESIGN: The assessment was based on evaluation of each subject's speech and velopharyngeal function through perceptual measures, nasometry, and video-nasendoscopy. SETTING: The study took place at the National Pediatric Center for Congenital Maxillofacial Pathology, Moscow, Russia, under the auspices and with the cooperation of Dr. Frolova, director of the program. SUBJECTS: One hundred twelve children (40 girls and 72 boys; age range, 4 to 10 years; mean age, 7.5 years) with repaired cleft palate who had undergone palatoplasty 2 to 4 years earlier and had no secondary surgery were randomly selected from the center's clinical files by the staff. Subjects with known conditions that could jeopardize normal speech development were excluded. METHODS: Each subject was assessed for speech and velopharyngeal function with a battery of perceptual measures and videonasendoscopy. RESULTS: The percentage of subjects judged to have normal resonance was 55.5%. An additional 9.5% of the subjects judged to be hyponasal increased the rate of nonhypernasal outcome to 64%. CONCLUSIONS: The Furlow double-Z palatoplasty has had an increasing rate of success (up to 87%), whereas the Frolova technique has a success rate of only 55% to 65%.

Child↗

PubMed1998

Otologic and audiologic status of Russian children with cleft lip and palate.

OBJECTIVE: In this study, researchers evaluated the otologic and audiologic status of 112 children with repaired cleft lip and palate who had received primary palatal repair by means of Frolova palatoplasty, a surgical technique developed by Dr. Larisa Y. Frolova, founder and director of the National Pediatric Center for Congenital Maxillofacial Pathology, Moscow, Russia. DESIGN: Results of hearing thresholds and tympanograms for these Russian children were compared with data previously reported from a group of 48 children and adults with repaired cleft lip and palate at the University of Florida Craniofacial Center, Gainesville, Florida. RESULTS: There were no substantial differences in hearing thresholds between the two groups, which was surprising in view of the vast differences between middle ear management techniques used in Russia and the United States. CONCLUSIONS: Considering these findings and the growing body of literature favoring a more conservative approach to the management of middle ear effusion in infants with cleft lip and palate, a reexamination of otologic strategies in the United States seems advisable.

Acoustic Impedance Tests↗

PubMed1997

Effects of intermittent transdermal nitroglycerin on occurrence of ischemia after patch removal: results of the second transdermal intermittent dosing evaluation study (TIDES-II).

OBJECTIVES: We sought to evaluate the effects of intermittent transdermal nitroglycerin (TD-NTG) on the occurrence of ischemia during patch-off hours in patients with stable angina pectoris receiving a beta-adrenergic blocking agent or calcium antagonist, or both. BACKGROUND: The current recommendations for the use of intermittent TD-NTG may be associated with the occurrence of rebound ischemia. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled, crossover trial with three study periods. Tolerability to TD-NTG was assessed in Period I. Seventy-two patients were assigned to receive either double-blind transdermal placebo or maximally tolerated TD-NTG for 2 weeks (Period II) and were then crossed over to the alternative treatment for another 2 weeks (Period III). The patients were instructed to apply medication daily at 8 AM, to remove it at 10 PM and to note symptoms and sublingual nitroglycerin (SL-NTG) use in a diary. The occurrence of ischemia was assessed from patient-perceived angina, symptom-limited exercise treadmill test (ETT) and 48-h ambulatory electrocardiographic (AECG) monitoring. RESULTS: Transdermal NTG (0.2 to 0.4 mg/h) significantly reduced the magnitude of ST segment depression at angina onset during ETT compared with placebo. Total angina frequency was not significantly different between TD-NTG (mean [+/-SD] 3.2 +/- 4.2) and placebo (3.3 +/- 5.2). During patch-off hours, angina frequency increased with TD-NTG (1.1 +/- 2.1) compared with placebo (0.7 +/- 1.6) (p = 0.03). Similar trends for an increase in ischemia after TD-NTG were also observed from AECG analyses. Specifically, ischemia frequency tended to be lower during patch-off hours for placebo than with TD-NTG (0.05 +/- 0.09 vs. 0.08 +/- 0.20 episodes/h, respectively, p = 0.08), even though frequency of ischemia tended to be higher during patch-on hours for placebo than with TD-NTG (0.12 +/- 0.19 vs. 0.07 +/- 0.15 episodes/h, respectively, p = 0.11). During placebo, ischemia frequency decreased 58% (patch-on to patch-off, p = 0.01) compared with a 14% increase with TD-NTG. These changes attenuate the usual circadian variation in ischemia. CONCLUSIONS: An increase in ischemia frequency during patch-off hours after use of intermittent TD-NTG was perceived by patients, and this subjective finding was supported by a corresponding trend for AECG ischemia to increase during these same hours.

Administration, Cutaneous↗

PubMed1996

Fimbrial-mediated colonization of murine teeth by Actinomyces naeslundii.

Groups of mice fed diets high in sucrose or glucose were orally inoculated with 10(10), 10(9) or 10(8) colony-forming units of one of the following Actinomyces naeslundii strains possessing the type 1 (T1+) and/or the type 2 (T2+) fimbriae: T14VJ1 (T1+, T2+), 5519 (T1+), 5951 (T2+), and 147 (non-fimbriated). Ninety-six hours after inoculation their upper jaws were cultured to look at the implantation of each of these strains on the teeth. In mice fed a sucrose diet, regardless of the presence or absence of fimbriae, each bacterial strain colonized 100% of the mice at the highest inoculation doses of the infecting organism. But at a dose of 10(8), T14V-J1 was the only strain which colonized 100% (12/12) of the mice, 5519 colonized 10/11, 5951 colonized 9/11 and 147 colonized 7/11. These differences were not statistically significant. When mice were fed a high-glucose diet, 100% infection was achieved with strains T14V-J1, 5519 and 5951 only at the highest dose of 10(10) colony-forming units. Strain 147 colonized in 8/9 of the mice at that dosage. At lower dosages, no bacterial strain implanted in 100% of the mice. In the glucose experiment at a dose of 10(8), strains expressing the T1 fimbriae implanted significantly better than strains without the T1 fimbriae. At a dose of 10(9) colony-forming units, the parent strain T14V-J1 implanted significantly better than strains without the T1 fimbriae. Similarly, strain 5519 (T1+) implanted significantly better than 5951 and implanted better than 147, although the difference was not significant. These results suggest that while the presence of the T1 and T2 fimbriae may confer some advantage in the establishment of these organisms in vivo, even the strains without fimbriae were able to colonize. Strains T14VJ1 and 5519 were found to bind well to hydroxyapatite treated with mouse saliva, while strains 5951 and 147 did not. Only T2 fimbriated strains T14V-J1 and 5951 exhibited a lactose-reversible coaggreation with indigenous strains of enterococci that may contribute to the elevated levels of colonization of strain 5951 in vivo.

Actinomyces↗

PubMed1995

Astigmatism reduction clinical trial: a multicenter prospective evaluation of the predictability of arcuate keratotomy. Evaluation of surgical nomogram predictability. ARC-T Study Group.

OBJECTIVE: To determine the accuracy of the Lindstrom surgical nomogram for astigmatism. DESIGN: A prospective multicenter study. PATIENTS: One hundred sixty eyes of 95 patients underwent astigmatic keratotomy in eight centers by nine surgeons. Inclusion criteria for the study included age of at least 18 years with 1 to 6 diopters (D) of naturally occurring corneal astigmatism and less than 1 D of lenticular astigmatism. INTERVENTIONS: A standardized astigmatic keratotomy surgical technique was performed on each eye. Surgical measurements were determined using the Lindstrom surgical nomogram for astigmatism. MAIN OUTCOME MEASURE: The Holladay, Cravy, Koch vector analysis method was used to determine the change in refractive cylinder results. Refractive changes also are presented without vector analysis merely using the absolute change in refractive cylinder and axis. RESULTS: Multiple regression analysis was used to develop a mathematical model determining the factors predictive of the change in refractive cylinder. The significant predictors for the amount of astigmatic correction achieved were, in order of decreasing importance, the following: number of incisions (R2 = 30%), incision length (R2 = 16%), age (R2 = 8%), and gender (R2 = 2%). CONCLUSIONS: Astigmatism is a two-dimensional measurement of both quantity and direction that is most appropriately analyzed with vector analysis. The original Lindstrom surgical nomogram for arcuate keratotomy used in this study is still quite useful although it tended to underpredict results for many patients, especially those having two incisional surgeries. Some older subjects having minimal surgery achieved greater correction than predicted by the original nomogram. The most important factors predictive of greater astigmatic keratotomy surgical effect are incision number, incision length, older age, and male gender.

Adult↗

PubMed1995

Ten-year refractive and visual results of radial keratotomy.

PURPOSE: The authors evaluated the 10-year refractive and visual acuity results of a cohort of patients who underwent radial keratotomy (RK). METHODS: A prospective cohort study was begun in 1980 of 198 consecutive myopic eyes of patients who were to undergo RK surgery. Patients were at least 18 years of age with myopia between 1.75 and 10 diopters. All patients signed consent forms. Refraction, uncorrected visual acuity (UVA), and best corrected visual acuity (BCVA) were the main outcomes evaluated at 10 years. RESULTS: Mean refraction at 10 years was -0.12 D, compared with -0.43 D at 5 years. Fifty-seven percent of eyes had UVA of at least 20/40 at 10 years, compared with 55% at 5 years. Improvement in UVA between 5 and 10 years occurred most frequently in eyes with most preoperative myopia and most surgery. Eighty-five percent of eyes had BCVA of at least 20/25 at 10 years, compared with 81% at 5 years. Women had significantly less myopia then men before surgery (P < 0.01), yet had similar UVA and worse BCVA. At 10 years, women had similar refraction but worse UVA and BCVA than men. CONCLUSIONS: Radial keratotomy was shown to be effective 10 years later. Some refractive and acuity changes occurred between 5 and 10 years follow-up, but these were mainly normal physiologic changes that occur with aging. Women had poorer vision than men before RK surgery and less beneficial results after surgery.

Adult↗

PubMed1995

A longitudinal evaluation of dipyridamole drug use in an ambulatory elderly population.

STUDY OBJECTIVE: To determine the pattern of dipyridamole use over the past 14 years. DESIGN: A longitudinal health screening program of ambulatory elderly participants was used to study changes in dipyridamole drug use. Participants included all subjects screened in the Florida Geriatric Research Program since 1978. The main outcome measure in this study was self-reported dipyridamole use at every visit to the program since August 1, 1978. RESULTS: A total of 3.6% of men (mean age, 82.6 years) and 3.4% of women (mean age, 80.8 years) reported the use of dipyridamole in the 1991-1992 period. The prevalence of dipyridamole use ranged from a low of 1.6% in 1978-1979 to a high of 7.3% in 1986-1987. There was a significant increase in the use of this drug from 1978-1979 to 1991-1992 (p < 0.038). Over the 14-year period of study, the percent of subjects using dipyridamole concurrently with coumarin anticoagulants ranged from a low of 5.8% to a high of 17.9%. CONCLUSIONS: The level of dipyridamole use in this elderly population has increased since 1978-1979. The only FDA indication for this drug is in combination with coumarin anticoagulants to prevent postoperative thromboembolic complications of cardiac valve replacement. Less than 20% of patients in this study used the drug in combination with coumarin anticoagulants. Educational programs are needed to improve the prescribing of dipyridamole.

Aged↗

PubMed1994

Characteristics of a contemporary population with angina pectoris. TIDES Investigators.

To characterize a contemporary, nonhospitalized population with angina pectoris, data were obtained from a geographically diverse cohort of 5,125 outpatients with chronic stable angina cared for by 1,266 primary care physicians between September and November of 1990. Diagnosis was based on history supported by evidence for coronary artery disease (coronary angiography, old myocardial infarction, or an abnormal stress test, either alone or in combination). The mean age of the patients was 69 years and 53% were women. Seventy percent had > 1 associated illness and 64% took > 1 cardiovascular drug. Median angina frequency was approximately 2 episodes/week and increased angina frequency (p < 0.0001) was associated with decreased overall feeling of well-being. Although effort angina was present in 90% of patients, 47% also had rest angina and 35% had mental stress-evoked angina. Female gender (relative risk [RR] 1.09; 95% confidence interval [CI] 1.02 to 1.16), concomitant illness (RR 1.17; CI 1.09 to 1.25), and pharmacotherapy (RR 1.14; CI 1.07 to 1.22) were associated with excess risk for rest angina. Younger age (RR 1.30; CI 1.20 to 1.41), female gender (RR 1.16; CI 1.07 to 1.26), concomitant illness (RR 1.13; CI 1.03 to 1.24), and pharmacotherapy (RR 1.28; CI 1.15 to 1.93) were associated with excess risk for mental stress angina. These data suggest that contemporary outpatients with angina are frequently women and elderly patients with high rates of associated illness, rest, and mental stress-related angina.

Administration, Cutaneous↗

PubMed1994

Treatment of subjects with refractory periodontal disease.

The aim of the present study was to evaluate the effect of non-surgical periodontal therapy with the adjunct of a selected antibiotic in subjects diagnosed with refractory periodontal disease. 21 subjects were selected for the study; all had a history of periodontal surgery, tetracycline therapy, and regular maintenance by a periodontist. When disease activity was detected, a bacterial sample was taken and a whole plaque susceptibility test was performed. Before the outcome of the susceptibility test the subjects were assigned to either antibiotic or placebo therapy. All subjects received scaling and rootplaning prior to antibiotic or placebo therapy. Based on the susceptibility test, subjects in the antibiotic group were treated either with Augmentin or clindamycin. The results demonstrated that in subjects with refractory periodontal disease there was no significant difference (N.S.) in the proportion of sites losing attachment before and after treatment (11.3% and 12.4%, respectively) over a 2-year post therapy observation period. However, the proportion of sites showing gain of attachment increased from 0.9% before therapy to 5.1% (p = 0.029) following selective antibiotic therapy when combined with scaling and rootplaning. The remainder of sites showed no change between pre- and post-therapy monitoring periods. The progression of attachment loss in the active sites could not be completely stopped over the entire 2-year period. After 12-15 months following therapy, there was a tendency towards new loss of attachment and an increase of pocket depth. However, all 4 subjects treated with placebo drug demonstrated continuous deterioration and had to be retreated. Although the proportion of sites losing attachment decreased from 5.1% to 2.3% (N.S.), the proportion of sites gaining attachment also decreased from 2.0% to 1.0% (N.S.). The results suggest that scaling and rootplaning together with selected antibiotic therapy repeated every 12-15 months may be beneficial for these subjects although it may not completely stop progressive attachment loss.

Adult↗

PubMed1994

Effects of treatment on outcome in mildly symptomatic patients with ischemia during daily life. The Atenolol Silent Ischemia Study (ASIST)

BACKGROUND: Detection of asymptomatic ischemia in patients with coronary artery disease has been associated with increased risk for adverse outcome, but treatment of patients with asymptomatic ischemia remains controversial. Accordingly, the purpose of this study was to determine if treatment reduces adverse outcome in patients with daily life ischemia. METHODS AND RESULTS: A multicenter, randomized, double-blind, placebo-controlled study of asymptomatic or minimally symptomatic outpatients with daily life silent ischemia due to coronary artery disease was conducted. The primary outcome measure was event-free survival at 1 year by Kaplan-Meier analysis. Events were death, resuscitated ventricular tachycardia/fibrillation, myocardial infarction, hospitalization for unstable angina, aggravation of angina, or revascularization. The secondary outcome was ischemia during ambulatory ECG monitoring at 4 weeks. Three hundred six outpatients with mild or no angina (Canadian Cardiovascular Society class I or II), abnormal exercise tests, and ischemia on ambulatory monitoring were randomized to receive either atenolol (100 mg/d) or placebo. After 4 weeks of treatment, the number (mean +/- SD, 3.6 +/- 4.2 versus 1.7 +/- 4.6 episodes, P < .001) and average duration (30 +/- 3.3 versus 16.4 +/- 6.7 minutes, P < .001) of ischemic episodes per 48 hours of ambulatory monitoring decreased in atenolol- compared with placebo-assigned patients (4.4 +/- 4.6 to 3.1 +/- 6.0 episodes and 36.6 +/- 4.1 to 30 +/- 5.5 minutes). Event-free survival improved in atenolol-treated patients (P < .0066), who had an increased time to onset of first adverse event (120 versus 79 days) and fewer total first events compared with placebo (relative risk, 0.44; 95% confidence intervals, 0.26 to 0.75; P = .001). There was a nonsignificant trend for fewer serious events (death, resuscitation from ventricular tachycardia/fibrillation, nonfatal myocardial infarction, or hospitalization for unstable angina) in atenolol-treated patients (relative risk, 0.55; 95% confidence intervals, 0.22 to 1.33; P = .175). The most powerful univariate and multivariate correlate of event-free survival was absence of ischemia on ambulatory monitoring at 4 weeks. Side effects were mild and generally similar comparing atenolol- and placebo-treated patients, although bradycardia was more frequent with atenolol. CONCLUSIONS: Atenolol treatment reduced daily life ischemia and was associated with reduced risk for adverse outcome in asymptomatic and mildly symptomatic patients compared with placebo.

Activities of Daily Living↗

PubMed1994

Modeling the relationship between clinical, microbiologic, and immunologic parameters and alveolar bone levels in an elderly population.

A cross-sectional periodontal study of 74 subjects aged 65 to 75 years was performed. Clinical data were collected and related to microbiological and immunological data. A statistical model (step-wise multiple regression) of factors related to bone loss was created initially using clinical data only; then by adding either the microbiologic or immunologic data; and then by using clinical, microbiologic, and immunologic data together. When only clinical data were considered, three factors were found to have significant positive correlations with bone loss. Tooth mobility accounted for 17% of the variability in the alveolar bone level measurements, probing depth for 12%(r2), and plaque index for 3%, for a total of 32% of the variability explained by these clinical factors. Tooth mobility and probing depth were clinical factors which remained significant in the model when the microbiological data were also considered. As percentages of the total cultivable microbiota, E. corrodens (r2 = 14%) and black-pigmenting Prevotella intermedia (r2 = 4%) correlated positively with alveolar bone loss. The addition of the microbiologic data only increased the r2 to 33%. When immunological data were considered with the clinical data, pocket depth and tooth mobility were the clinical parameters which remained in the model. IgG antibody levels to P. gingivalis W83 and/or 381 (r2 = 24%) A. actinomycetemcomitans 627 (r2 = 2%) were the significant immunologic measures having a positive correlation with bone loss. Anti-F. nucleatum levels had a significant negative correlation. A total of 50% of the variability in alveolar bone level was accounted for in the model by the addition of specific serum antibody levels to subgingival plaque microorganisms. When clinical, microbiological, and immunological measurements were all considered together, antibody to P. gingivalis W83 and/or 381 (r2 = 42%), percentage of B-lymphocytes (r2 = 3%), probing depth (r2 = 4%), anti-E. corrodens levels (r2 = 2%), and anti-P. gingivalis 33277 levels (r2 = 4%) all had significant positive correlation with loss of alveolar bone. The number of enteric bacteria, anti-F. nucleatum levels, and anti-P. intermedia levels each had a significant negative correlation with alveolar bone heights. The r2 for this model was 75%. These results indicated that antibody levels to subgingival plaque microorganisms and tooth mobility were the best predictors of bone loss in the elderly patients tested in this study.

Age Factors↗

PubMed1994

Results from a three-year caries clinical trial comparing NaF and SMFP fluoride formulations.

A three-year, double blind, randomised clinical trial was conducted in Polk County, Florida from 1983-1987. The objective was to compare the effect of four dose levels of sodium monofluorophosphate (SMFP) and a single dose level of sodium fluoride (NaF) on DMFS, DMFT, and DFS Interproximal indices. A total of 8,027 children were examined clinically and radiographically at baseline, and 5,474 children completed the three-year study, which included daily supervised brushing at school. No differences existed at baseline between the five study cells on age or gender distribution, or on any of the dental indices. Results indicated that the 2000 ppm F NaF group had significantly smaller DMFS increment than the 2000 ppm F SMFP group p < 0.005. The 2000 ppm F NaF group demonstrated an 18 per cent (26 per cent for children > 10 years at baseline) reduction in DMFS over the 1500 ppm F SMFP group, the 2500 ppm F group a 15 per cent (19 per cent) reduction, and the 2000 ppm F SMFP a 5 per cent (9 per cent) reduction. Results are strongest in children at greatest risk--older children with previous caries. This study concludes that the anticaries efficacy of SMFP dentifrices rises with increasing fluoride, and that the anticaries efficacy of a 2000 ppm NaF dentifrice is superior to that of a 2000 ppm F SMFP dentifrice, p < 0.005).

Adolescent↗

PubMed1993

Five-year corneal graft survival. A large, single-center patient cohort.

OBJECTIVE: To determine the survival rates and causes of secondary graft failure in a large, consecutive series of penetrating keratoplasties. DESIGN: All eyes undergoing penetrating keratoplasty at a single center were evaluated for factors relating to penetrating keratoplasty preoperatively, surgically, and postoperatively at 1, 3, 6, 9, 12, 18, and 24 months and then at yearly intervals. Since 1986, data analysis has been prospective. SETTING: A large, private practice, tertiary center for corneal disorders and surgery. PATIENTS: A consecutive series of 1819 penetrating keratoplasties performed from August 1982 through August 1990; 13 eyes with primary graft failure were excluded. MAIN OUTCOME MEASURE: Graft failure and causes of failure. Follow-up ranged from 1 to 96 months, with a mean of 26.6 months. RESULTS: Pseudophakic bullous keratopathy was the most common diagnosis necessitating keratoplasty (38.6%). Secondary failures occurred 111 times (6.1%). The 2- and 5-year survival rates for all grafts in the study were 95% and 91%, respectively. While endothelial failure as a result of immunologic allograft reactions was the most common cause of graft failure (27%), problems with the external surface of the graft caused nearly as many failures (25%). The risk of failure from surface-related problems was highest at 3 months after surgery. There were significantly decreased survival rates for grafts in eyes with regrafts (P < .0001), in eyes left aphakic at keratoplasty (P < .0001), and in eyes with deep stromal vascularization (P < .0001). CONCLUSION: Penetrating keratoplasty is a successful form of transplantation, and survival rates are gradually increasing. The risk of graft failure appears highest within the first year after transplantation.

Adolescent↗

PubMed1993

Evaluation of reliability and reproducibility of dental indices.

Evaluation of periodontal therapy involves the use of several oral indices to describe the health status of hard and soft tissues. It was the objective of the present study to evaluate the reliability and reproducibility of some of these indices. A calibration and standardization session was designed to calibrate 10 examiners and a "gold standard" (an experienced examiner) in evaluating the following indices: the Volpe-Manhold calculus index (VM), the Lobene stain index (SI), a non-invasive modification of the Löe-Silness gingival index (GI), the papillary bleeding score (PBS) of Loesche, and the plaque index (PI) of Quigley-Hein as modified by Turesky. For each index, the average intraclass correlation was calculated between two subject visits. The highest intraclass correlation, 0.94, was found for PBS. The intraclass correlation for PI was 0.70 and for VM, 0.65. The lowest intraclass correlations were for stain, 0.47, and GI, 0.25. Intra-subject correlations between the 2 visits were good for all indices, but were best for PBS, followed by VM. PBS seems to be the most reliable index (both intra- and inter-examiner) for measuring the oral health status and is therefore recommended for use in clinical studies.

Analysis of Variance↗

PubMed1993

Change detection on longitudinal data in periodontal research.

Longitudinal data of attachment level (AL) or the alveolar bone level are often used to assess the progression of periodontal disease. This paper tries to identify the most efficient method to detect the changes of AL in a general periodontal research environment; that is, a sequential decision based on multiple sites. Several existing methods suggested in the periodontal research literature such as the tolerance, running median, cusum, and regression methods as well as change-point detection methods in the statistical literature are examined. It is found that the regression method is most convenient among the several methods that are equally effective in change detection. Formulae, tables and their usage are discussed in detail.

Decision Support Techniques↗

PubMed1992

Nocturia: a risk factor for falls in the elderly.

OBJECTIVE: To determine if nocturia is a risk factor for reported falls and bone fractures in older persons. DESIGN: Cross-sectional study comparing falls in men and women with and without nocturia. SETTING: Longitudinal health screening program of ambulatory elderly participants. PARTICIPANTS: Participants included 988 (65.5%) women and 520 (34.5%) men who had completed their tenth annual visit to the program. MAIN OUTCOME MEASURES: Reported falls in the past year and reported bone fractures in the past 5 years. RESULTS: Participants who reported nocturia at least twice during the night were at significantly greater risk to report falls (Odds Ratio = 1.84; 95% CI = 1.05-3.22), and the risk increased in subjects reporting more than three nocturia events (Odds Ratio = 2.15; 95% CI = 1.04-4.44). The significant increase in falls reported by nocturia participants did not result in an increase in reported bone fractures in the past 5 years (P < 0.4360). CONCLUSIONS: Nocturia is an important risk factor for falls in ambulatory elderly persons. Preventive measures should be taken to decrease nocturia events and to decrease the risk of falling during these nocturia events.

Accidental Falls↗