Charles Spiekerman

Daytime Sleepiness Predicts Mortality and Cardiovascular Disease in Older Adults

INTRODUCTION: As part of the baseline examination in the Cardiovascular Health Study, sleep disturbance symptoms including snoring and daytime sleepiness, were assessed as potential risk factors or precipitants of cardiovascular disease (CVD). Because of the association of sleep disturbance with poorer health and the possible associations of sleep apnea with CVD, we hypothesized that those with poorer sleep or daytime sleepiness may be at increased risk of mortality or incident CVD.

Cardiovascular disease in older adults with glucose disorders: comparison of American Diabetes Association criteria for diabetes mellitus with WHO criteria

BACKGROUND The new fasting American Diabetes Association (ADA) criteria for the diagnosis of diabetes mellitus rely mainly on fasting blood glucose concentrations and use a lower cut-off value for diagnosis than the WHO criteria. We aimed to assess the sensitivity of these criteria for the detection of cardiovascular disease, the main complication of diabetes mellitus in the elderly. METHODS We did a cross-sectional and prospective analysis of 4515 participants of the Cardiovascular Health Study, an 8 year longitudinal study designed to identify factors related to the onset and course of cardiovascular disease in adults aged at least 65 years. We calculated the prevalence and incidence of cardiovascular disease for the ADA and WHO criteria. FINDINGS There was a higher prevalence of cardiovascular disease among individuals with impaired glucose or newly diagnosed diabetes by both criteria than among those with normal glucose concentrations. However, because fewer individuals had abnormal glucose states by the fasting ADA criteria (22.3%) than by the WHO criteria (46.8%), the number of cases of cardiovascular disease attributable to abnormal glucose states was a third of that attributable by the WHO criteria (53 vs 159 cases per 10,000). For the two sets of criteria, the relative risk for incident cardiovascular disease (mean follow-up 5.9 years) was higher in individuals with impaired glucose and newly diagnosed diabetes than in those with normal glucose. Individuals classified as normal by the fasting ADA criteria had a higher absolute number of incident events (455 of 581 events) than those classified as normal by the WHO criteria (269 of 581 events). Fasting ADA criteria were therefore less sensitive than the WHO criteria for predicting cardiovascular disease among individuals with abnormal glucose (sensitivity, 28% vs 54%). INTERPRETATION The new fasting ADA criteria seem to be less predictive than the WHO criteria for the burden of cardiovascular disease associated with abnormal glucose in the elderly.

The Biomechanical Function of the Anterolateral Ligament of the Knee

Background: Recent anatomic investigations of the lateral structures of the knee have identified a new ligament, called the anterolateral ligament (ALL). To date, the anterolateral ligament has not been biomechanically tested to determine its function. Hypothesis: The ALL of the knee will resist internal rotation at high angles of flexion but will not resist anterior drawer forces. Study Design: Controlled laboratory study. Methods: Eleven cadaveric knees were subjected to 134 N of anterior drawer at flexion angles between 0° and 90° and separately to 5 N·m of internal rotation at the same flexion angles. The in situ forces of the ALL, anterior cruciate ligament (ACL), and lateral collateral ligament (LCL) were determined by the principle of superposition. Results: The contribution of the ALL during internal rotation increased significantly with increasing flexion, whereas that of the ACL decreased significantly. At knee flexion angles greater than 30°, the contribution of the ALL exceeded that of the ACL. During anterior drawer, the forces in the ALL were significantly less than the forces in the ACL at all flexion angles (P < .001). The forces in the LCL were significantly less than those in either the ACL or the ALL at all flexion angles for both anterior drawer and internal rotation (P < .001). Conclusion: The ALL is an important stabilizer of internal rotation at flexion angles greater than 35°; however, it is minimally loaded during anterior drawer at all flexion angles. The ACL is the primary resister during anterior drawer at all flexion angles and during internal rotation at flexion angles less than 35°. Clinical Relevance: Damage to the ALL of the knee could result in knee instability at high angles of flexion. It is possible that a positive pivot-shift sign may be observed in some patients with an intact ACL but with damage to the ALL. This work may have implications for extra-articular reconstruction in patients with chronic anterolateral instability.

An exploration of the periodontitis-cancer association

PURPOSE Periodontitis has been linked to the occurrence of various systemic diseases. The goal of this study was to explore the periodontitis-cancer association in the NHANES I Epidemiologic Follow-up Study. METHODS Data were available on 11,328 adults, age 25 to 74 years, who were diagnosed as dentate individuals with either periodontitis (n = 2092), gingivitis (n = 2603), a healthy periodontium (n = 2,671), or as individuals without teeth (edentulous n = 3,962) at the beginning of the follow-up. The main outcome measure was fatal cancer, as ascertained from death certificates. RESULTS Compared with individuals with a healthy periodontium, fatal cancer occurrence was positively associated with periodontitis at baseline (age and gender adjusted odds ratio = 1.55, 95% confidence interval: 1.25-1.92). Of the different cancer types, lung cancer demonstrated the strongest association. After adjustment for known risk factors for lung cancer, the magnitude of the association between periodontitis and lung cancer ranged between 1.48 (95% confidence interval: 0.88-2.50) and 1.73 (95% confidence interval: 1.01-2.97). CONCLUSIONS Associations between periodontitis and lung cancer mortality can be identified above and beyond adjustment for known risk factors for lung cancer. Despite these apparent unconfounded associations, there are reasons to believe that the periodontitis-cancer associations may be spurious.

Pre-existing Cardiovascular Disease and Periodontitis: A Follow-up Study

Periodontal infections in individuals with pre-existing heart disease are believed to increase the risk for future coronary heart disease (CHD) events. The goal of this study was to search for an association between periodontitis and CHD events among individuals with pre-existing heart disease, reported in the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Dentate adults (n = 636) with a history of pre-existing cardiovascular disease were followed for CHD events. The presence of periodontitis and gingivitis did not increase CHD risk among these at-risk individuals (hazard ratio [HR], 0.97, and 95% confidence interval [CI], 0.72-1.31; and HR, 1.09, and 95% CI, 0.79-1.50, respectively). When limited to individuals with a self-reported prior heart attack, periodontitis was associated with a 34% decreased CHD risk (HR, 0.66; 95% CI, 0.42-1.05). It is concluded that periodontitis or gingivitis does not elevate CHD risk among individuals with a prior heart attack or self-reported pre-existing cardiovascular disease.

Shear bond strengths of pressed and layered veneering ceramics to high-noble alloy and zirconia cores

STATEMENT OF PROBLEM Heat-pressed ceramics to metal alloys and zirconia have been available for some time. However, information regarding their shear bond strengths is limited. PURPOSE The purpose of this study was to evaluate the shear bond strengths of heat-pressed and layered ceramics with regard to their corresponding high-noble alloy and zirconia cores. MATERIAL AND METHODS Forty cylinders (approx. 5 mm in diameter) of high-noble alloy (Olympia) were cast and divided into 4 groups (n=10). Metal cylinders were veneered with ceramics to produce shear test specimens: Group PMI with IPS InLine POM; Group LMI with IPS InLine; Group PMC with Pulse press-to-metal; and Group LMC with Authentic Pulse Metal ceramic. Forty cylinders (approx. 5 mm in diameter) of zirconia (Lava) were obtained and divided into 4 groups (n=10). These cylinders were veneered with ceramics to produce shear test specimens: Group PZI with IPS e.max ZirPress; Group LZI with IPS e.max. Ceram; Group PZV with VITA PM9; and Group LZV with VITA VM9. The veneering ceramics, 3 mm in thickness, were either pressed or layered to their corresponding cylinders. Thermal cycling was performed at 5°C and 55°C for 20,000 cycles with a 20 second dwell time. Shear bond strength testing was conducted in a universal testing machine, and the failure strengths were recorded. Fracture surfaces were characterized visually, under a stereomicroscope, and with a scanning electron microscope (SEM). Data were analyzed using rank-based Kruskal-Wallis and Mann-Whitney tests with Bonferroni correction to adjust for multiple comparisons (α=.05). RESULTS For metal ceramic specimens, the mean (SD) shear bond strengths ranged from 37.8 (20.6) MPa to 66.4 (22.1) MPa. There were significant differences between Groups PMI and PMC and between Groups LMI and PMC, in which Groups PMI and LMI had significantly higher strength values than Group PMC (P=.041). For zirconia ceramic specimens, the mean (SD) shear bond strengths ranged from 30.03 (9.49) MPa to 47.2 (13.0) MPa, with Group LZV having a significantly higher shear bond strength value than Group LZI (P=.012). Half of the Group PZV specimens failed during thermal cycling, and Group PZV was, therefore, excluded from statistical analysis. For all shear bond strength testing specimens, cohesive failures in the veneering ceramics were observed. CONCLUSIONS For shear bond strength of veneering ceramics to high-noble alloy, there was no significant difference between pressing and layering with the same manufacturer. For shear bond strength of veneering ceramics to zirconia, there was no significant difference between the pressed and layered groups.

Effectiveness of MI Paste Plus and PreviDent fluoride varnish for treatment of white spot lesions: A randomized controlled trial

INTRODUCTION White spot lesions are a common sequela of orthodontic therapy. In this parallel-group randomized trial, we assessed the effectiveness of 2 agents commonly used to ameliorate white spot lesions compared with a normal home-care regimen. METHODS Patients aged 12 to 20 years were recruited from the offices of orthodontists and dentists who belonged to the Practice-based Research Collaborative in Evidence-based Dentistry network. The patients had their orthodontic appliances removed within the past 2 months and had at least 1 white spot lesion affecting their maxillary incisors. The subjects were randomized to 1 of 3 arms: (1) an 8-week regimen of MI Paste Plus (GC America, Alsip, Ill), (2) a single application of PreviDent fluoride varnish (Colgate Oral Pharmaceuticals, New York, NY), and (3) usual home care (control). Photographs were taken at enrollment and 8 weeks later. Two panels consisting of 5 dental professionals and 5 laypersons assessed the before-and-after pairs of photographs in a blinded fashion. Objective assessments and self-assessments were also performed. RESULTS One hundred fifteen subjects completed the study; 34 were assigned to the MI Paste Plus group, 40 to the fluoride varnish group, and 41 to the control group. The mean improvements assessed by the professional panel were 21%, 29%, and 27% in the MI Paste Plus, fluoride varnish, and control groups, respectively.The results from the lay panel were 29%, 31%, and 25%, respectively. Objective improvements in the surface affected were 16%, 25%, and 17%, respectively; self-assessments of improvement were 37% in all 3 groups. No assessments indicated significant differences between subjects in the active arms compared with the control arm. CONCLUSIONS MI Paste Plus and PreviDent fluoride varnish do not appear to be more effective than normal home care for improving the appearance of white spot lesions over an 8-week period.

Effect of Aging on the Response of Ghrelin to Acute Weight Loss

OBJECTIVES: To determine whether the failure of the orexigenic hormone ghrelin to increase as it normally does with weight loss contributes to impaired weight recovery in older persons.

Accuracy of implant placement using precision surgical guides with varying occlusogingival heights: An in vitro study

STATEMENT OF PROBLEM Surgical guides may interfere with effective use of surgical instrumentation during implant placement in the posterior segments where interocclusal distance may be limited. PURPOSE The purpose of this study was to measure and compare the accuracy of posterior implant placement using 3 precision surgical guides with varying occlusogingival heights, and to evaluate the difference in accuracy of implant placement through precision guides as compared to freehand placement. MATERIAL AND METHODS Three groups of surgical guides were fabricated with occlusogingival heights of 4, 6, and 8 mm, respectively. A jig was fabricated to allow for accurate positioning in bone substitute blocks. Ninety implants were placed in the mandibular first molar site on a manikin. Thirty implants (Astra Tech AB) were placed for each group, with 15 through the guide and 15 freehand. Distances between a reference implant and each placed implant were measured at both implant and abutment levels using a coordinate measuring machine. Apex position and angular discrepancy were calculated using the coordinates of the centers of the implant platform and of the occlusal aspect of the abutment. Data was assessed using 2-way ANOVA (alpha=.05). RESULTS Two-way ANOVA demonstrated that guide height did not significantly affect the accuracy of the implant position. The distance from the reference point to the point of measurement was significantly smaller for placement through the guide compared to freehand placement at both implant (P<.001) and abutment levels (P<.001). The angular discrepancy was also significantly smaller for placement through the guide (P<.001). CONCLUSIONS Precision surgical guides with 4-mm occlusogingival height allow placement as accurate as precision guides with 8-mm height. Placement through the guide reproduced the target position more accurately than freehand insertion.

Effects of Bronchoconstriction, Minute Ventilation, and Deep Inspiration on the Composition of Exhaled Breath Condensate

BACKGROUND Exhaled breath condensate (EBC) is composed of droplets of airway surface liquid (ASL) diluted by water vapor. The goal of this study was to determine if the composition of EBC is affected by changes in airway caliber, minute ventilation, or forceful exhalation, factors that may differ among subjects with asthma in cross-sectional studies. METHODS In a group of subjects with asthma, we measured the effects of the following: (1) a series of three deep-inspiration and forceful-exhalation maneuvers; (2) a doubling of minute ventilation; and (3) acute bronchoconstriction induced by methacholine on EBC volume, dilution of ASL, and concentration of cysteinyl leukotrienes (CysLTs). RESULTS With the exception of an increase in EBC volume with increased minute ventilation, there were no significant changes in the volume, dilution, or levels of CysLTs in EBC introduced by each of these factors. The CIs surrounding the differences introduced by each factor showed that the maximum systematic errors due to these factors were modest. CONCLUSIONS These results indicate that changes in airway caliber, minute ventilation, or breathing pattern among subjects with asthma do not significantly alter the measurements of mediator concentrations in EBC.