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Chen X, Hodges JS, Shuman SK, Gatewood LC, Xu J. Predicting tooth loss for older adults with special needs. Community Dent Oral Epidemiol 2010; 38: 235–243. © 2010 John Wiley & Sons A/S Abstract – Objectives: Older Adults with Special Needs (OASN) have more oral health needs compared with healthy, independent elders. Currently, little is known about tooth loss, a key indicator of oral function loss, among OASN. Risk assessment is primarily based on clinical experience rather than scientific evidence, raising concerns for quality of care. The study’s objective was to develop an evidence-based model to quantitatively predict tooth loss for OASN. Methods: Four hundred ninety-one dentate older adults, including 235 from long-term care facilities, were retrospectively recruited. Subjects were treated and brought to a state of oral health before enrollment. Medical and dental assessments were abstracted from dental records and used to predict risk of tooth loss. Tooth loss events were recorded for subjects during follow-up. Multivariate negative-binomial regression was used, starting with 27 risk factors and removing variables using Akaike’s Information Criterion. Pearson’s correlation was then conducted to evaluate the overall fit of the final fitted model. Results: The final fitted model included eight predictors. Among them, age, number of decayed/broken teeth at arrival, anticholinergic burden of medications and physical mobility were associated with risk of tooth loss in OASN (P ≤ 0.05). Internal validation indicated satisfactory fit of the final fitted model. Conclusion: An evidence-based model with eight predictors was developed to quantitatively predict risk of tooth loss for OASN at the individual level.

Many statisticians have had the experience of fitting a linear model with uncorrelated errors, then adding a spatially-correlated error term (random effect) and finding that the estimates of the fixed-effect coefficients have changed substantially. We show that adding a spatially-correlated error term to a linear model is equivalent to adding a saturated collection of canonical regressors, the coefficients of which are shrunk toward zero, where the spatial map determines both the canonical regressors and the relative extent of the coefficients’ shrinkage. Adding a spatially-correlated error term can also be seen as inflating the error variances associated with specific contrasts of the data, where the spatial map determines the contrasts and the extent of error-variance inflation. We show how to avoid this spatial confounding by restricting the spatial random effect to the orthogonal complement (residual space) of the fixed effects, which we call restricted spatial regression. We consider five proposed in...

Objective: Despite the high prevalence of posttraumatic stress disorder (PTSD) among veterans treated at Department of Veterans Affairs (VA) facilities, rates of initiation of mental health treatment and persistence in treatment are unknown. This study examined outpatient treatment participation among veterans with a recent PTSD diagnosis and treatment differences according to the VA sector in which they received the diagnosis (PTSD specialty treatment program, general mental health clinic, and general medical clinic). Methods: Administrative data for 20,284 veterans who had received a diagnosis of PTSD at VA facilities were analyzed to determine rates of treatment initiation (any psychotropic prescription, an antidepressant prescription, behavioral counseling, and either a prescription or counseling) and maintenance of pharmacotherapy (at least four 30-day supplies), and counseling (at least eight visits) for the six months after diagnosis. Results: Approximately two-thirds of the sample initiated treatment: 50% received a psychotropic medication and 39% received some counseling; 64% received either medication or counseling. About half of those given medication (54%) received at least a four-month supply, and 24% of those given counseling had at least eight sessions. Overall, 33% received minimally adequate treatment. Initiation, type, and duration varied by treatment sector: receipt of a diagnosis in a PTSD specialty program or a mental health clinic conferred small but significant benefits over receipt in a general medical clinic. Conclusions: Greater availability of mental health specialty services, particularly PTSD services, may be needed to ensure that veterans receive minimally adequate treatment after a PTSD diagnosis. (Psychiatric Services 61:58–63, 2010)

Objectives This study was designed to define more completely the clinical spectrum and consequences of stress cardiomyopathy (SC) beyond the acute event. Background Stress cardiomyopathy is a recently recognized condition characterized by transient cardiac dysfunction with ventricular ballooning. Methods Clinical profile and outcome were prospectively assessed in 136 consecutive SC patients. Results Patients were predominantly women (n = 130; 96%), but 6 were men (4%). Ages were 32 to 94 years (mean age 68 ± 13 years); 13 (10%) were ≤50 years of age. In 121 patients (89%), SC was precipitated by intensely stressful emotional (n = 64) or physical (n = 57) events, including 22 associated with sympathomimetic drugs or medical/surgical procedures; 15 other patients (11%) had no evident stress trigger. Twenty-five patients (18%) were taking beta-blockers at the time of SC events. Three diverse ventricular contraction patterns were defined by cardiovascular magnetic resonance (CMR) imaging, usually with rapid return to normal systolic function, although delayed >2 months in 5%. Right and/or left ventricular thrombi were identified in 5 patients (predominantly by CMR imaging), including 2 with embolic events. Three patients (2%) died in-hospital and 116 (85%) have survived, including 5% with nonfatal recurrent SC events. All-cause mortality during follow-up exceeded a matched general population (p = 0.016) with most deaths occurring in the first year. Conclusions In this large SC cohort, the clinical spectrum was heterogeneous with about one-third either male, ≤50 years of age, without a stress trigger, or with in-hospital death, nonfatal recurrence, embolic stroke, or delayed normalization of ejection fraction. Beta-blocking drugs were not absolutely protective and SC was a marker for increased noncardiac mortality. These data support expanded management and surveillance strategies including CMR imaging and consideration for anticoagulation.

The resonances originating from proteins underlie those of metabolites in brain 1 H nuclear magnetic resonance (NMR) spectra. These resonances have different physical properties from those of metabolites, such as shorter T1 and T2 relaxation time constants. The age dependence of the macromolecular pattern and content in the human brain was investigated with a focus on adults over 66 years of age using ultrahigh-field in vivo magnetic resonance spectroscopy. Eighteen young and 23 cognitively normal older adults were studied at 7 T. Metabolite spectra were acquired in the occipital cortex and the posterior cingulate cortex with single-voxel stimulated echo acquisition mode (STEAM) spectroscopy in 14 young and 20 older adults. Macromolecular spectra were acquired in the occipital cortex using an inversion recovery STEAM sequence in four young and three older adults. The macromolecular pattern was apparent over the 0.5-4.5-ppm range in the inversion recovery spectra and the 0.5-2-ppm range in the metabolite spectra. Macromolecular content was quantified from metabolite spectra using LCModel and from inversion recovery spectra using integration. Age-associated differences in the macromolecular pattern were apparent via both types of spectra, with the largest difference observed for the 1.7- and 2-ppm macromolecular resonances. A higher macromolecular content was observed in the older adults for both brain regions. Age-specific macromolecular spectra are needed when comparing metabolite spectra from subjects of differing ages because of age-associated differences in macromolecular pattern. Age-associated pattern and content differences may provide information about the aging process.

Introduction Osteoclastic activity is required for orthodontic force to move teeth through alveolar bone. Bisphosphonates are drugs that inhibit osteoclast maturation, function, and survival. The aim of this study was to assess orthodontic tooth movement in rats receiving bisphosphonate treatment. Methods Two groups of Sprague-Dawley rats were used. The rats in the treatment group received 7 mg per kilogram of body weight per week of alendronate sodium, and those in the control group received no drugs. A coil spring exerting a constant 50-g force was activated across the span from the central incisors to the first molar. As the first molar tipped mesially, a diastema between the first and second molars was created. Vinyl polysiloxane impressions were poured in die stone, and the diastema was measured indirectly with a charged-couple device microscope camera and Optimas software (Media Cybernetics, Newburyport, Mass). Results Statistical analysis with repeated-measures analysis of variance showed less orthodontic tooth movement in the alendronate group compared with control group (0.06 vs 0.24 mm at 2 weeks, and 0.45 vs 1.06 mm at 4 weeks; P = 0.0004 for the alendronate vs control main effect). Conclusions This study demonstrated an inhibitory effect of alendronate administration on orthodontic tooth movement in a rat model.

Annual insecticide spraying and artemisinin combination therapy may stop transmission., Highland areas where malaria transmission is unstable are targets for malaria elimination because transmission decreases to low levels during the dry season. In highland areas of Kipsamoite and Kapsisiywa, Kenya (population ≈7,400 persons), annual household indoor residual spraying with a synthetic pyrethroid was performed starting in 2005, and artemether/lumefantrine was implemented as first-line malaria treatment in October 2006. During April 2007–March 2008, no microscopy-confirmed cases of malaria occurred at the sites. In 4 assessments of asymptomatic persons during May 2007–April 2008, a total of

Many veterans with posttraumatic stress disorder (PTSD) either do not seek treatment or participate in treatment only episodically. The authors conducted a retrospective cohort study using Department of Veterans Affairs (VA) administrative data to determine rates of mental health care use and to examine whether the odds of service use varied by race or ethnicity. They examined all veterans with a new diagnosis of PTSD during a one-year period. Analyses used logistic or negative binomial regression with generalized estimating equations to measure associations of race and ethnicity with mental health service use after controlling for demographic, disability, and access factors. After adjustment, veteran race, but not Hispanic ethnicity, was associated with decreases in some pharmacotherapy measures and increases in some counseling measures.

The aim of this study aim was to determine whether elastic properties and apparent density of bone differ in different anatomical regions of the maxilla and mandible. Additional analyses assessed how elastic properties and apparent density were related. Four pairs of edentulous maxilla and mandibles were retrieved from fresh human cadavers. Bone samples from four anatomical regions (maxillary anterior, maxillary posterior, mandibular anterior, mandibular posterior) were obtained. Elastic modulus (EM) and hardness (H) were measured using the nano-indentation technique. Bone samples containing cortical and trabecular bone were used to measure composite apparent density (cAD) using Archimedes’ principle. Statistical analyses used repeated measures ANOVA and Pearson correlations. Bone physical properties differed between regions of the maxilla and mandible. Generally, mandible had higher physical property measurements than maxilla. EM and H were higher in posterior than in anterior regions; the reverse was true for cAD. Posterior maxillary cAD was significantly lower than that in the three other regions.

Patients with hypertrophic cardiomyopathy (HCM) and aborted cardiac arrest are generally regarded as a high-risk subgroup susceptible to future major cardiac events and an unfavorable prognosis. However, outcome over extended time periods after major arrhythmic events is unresolved in such HCM patients.This study sought to more completely define the natural history of HCM.Of 916 HCM patients in the Minneapolis Heart Institute registry, 39 experienced either cardiac arrest (n = 21) or an appropriate shock from a prophylactically implanted cardioverter-defibrillator (ICD) (n = 18), and were assessed prospectively.Age at initial arrhythmic event was 34 +/- 17 years (range 8 to 68; 67%40 years). Of the 39 study patients, 32 (82%) survived after their initial cardiac event (for 9.4 +/- 7.6 years; up to 30 years), including 14 patients foror=10 years (36%) and 4 patientsor=20 years (10%). Of the 32 survivors, 15 (47%) have not experienced subsequent events, and 17 (53%) hador=1 additional cardiac arrest or appropriate ICD intervention. Annual HCM-related mortality was 1.4%, similar to general HCM populations, and 88% of patients were free of HCM-related death over the follow-up period. Survival from potentially lethal arrhythmias was associated with no or only mild heart failure symptoms in 29 of 32 patients (91%) at most recent evaluation.In HCM, long-term survival up to 30 years may follow cardiac arrest with or without ICD intervention. Disabling heart failure symptoms were uncommon after these arrhythmic events, at last follow-up. These novel observations regarding the natural history of HCM underscore the unpredictability of the arrhythmogenic substrate, which may remain dormant over extended periods of time.

Mandibular repositioning appliance (MRA) therapy for snoring and obstructive sleep apnea (OSA) is an accepted treatment option for patients with mild to moderate disease. A recent comprehensive review of oral appliance therapy reported that patients with mild to severe OSA had a 52% chance of having an apnea-hypopnea index (AHI) < 10/h with a mandibular repositioning appliance.1 This rate of efficacy was not measurably better than that found in an earlier comprehensive literature review,2 despite improvements in the quality of the research studies and the introduction of titratable MRAs. In general, the adjustable MRA is initially set at 50% to 75% of maximum mandibular protrusion. The appliance is further advanced until symptoms improve or the maximum tolerated protrusion is reached. Overnight monitoring is usually done to determine the amount of objective improvement in apnea severity with MRA treatment. Despite the widespread use of titratable appliances, efficacy rates are not significantly better than those of fixed position appliances.1,2 Previous research has evaluated whether overnight titration of mandibular advancement during polysomnography could be used to initiate MRA therapy in a fashion similar to the titration of nasal continuous positive airway pressure (CPAP). The first study of overnight titration used an appliance that was removed from the patient's mouth and adjusted manually.3 Other titration studies have used a temporary appliance that can be adjusted either by awakening the patient4 or without awakening the patient.5,6 The temporary appliance was advanced either manually after removal of the temporary appliance,4 by a hydraulic system,5 or by remote control of a motorized system.6 However, results of these studies were mixed in terms of predicting the amount of advancement needed for successful MRA therapy. Furthermore, overnight titration of an MRA remains an experimental approach, and the technology for remote-controlled advancement is not widely available. Another method for appliance titration consists of clinical titration of the device to symptom resolution or to maximum tolerated advancement, with the addition of overnight home monitoring to determine objective improvement. The addition of home monitoring may provide data of an incomplete response that could allow further advancement to take place prior to outcome polysomnography (PSG). In a study of 40 patients using this approach, 64% of subjects had a complete response (AHI < 10/h with resolution of symptoms).7 Although this is a better success rate than in most studies of MRA therapy, many patients in this study were insufficiently treated despite an intensive clinical titration protocol. We evaluated a simple clinical protocol consisting of incremental advancement of an MRA by the patient to the point of good symptom control, followed by a titration PSG with the opportunity to further advance the appliance if needed. This titration PSG allowed for further advancement of the MRA during the night if the AHI remained high. The goal of the study was to determine if patients with an elevated AHI, despite the use of a clinically optimized MRA, could achieve better results with additional titration during the outcome PSG.

Statement of problem There is confusion in the literature about how physical properties of bone vary between maxillary and mandibular regions and which physical properties affect initial implant stability. Purpose The purpose of this study was to determine correlations between physical properties of bone and initial implant stability, and to determine how physical properties and initial stability vary among regions of jawbone. Material and Methods Four pairs of edentulous maxillae and mandibles were retrieved from fresh human cadavers. Six implants per pair were placed in different anatomical regions (maxillary anterior, right and left maxillary posterior, mandibular anterior, right and left mandibular posterior). Immediately after surgery, initial implant stability was measured with a resonance frequency device and a tapping device. Implant surgeries and initial stability measurements were performed within 72 hours of death. Elastic modulus (EM) and hardness were measured using nano-indentation. Composite apparent density (cAD) was measured using Archimedes' principle. Bone-implant contact percentage and cortical bone thickness were recorded histomorphometrically. Mixed linear models and univariate-correlation analyses were used (α=.05). Results Generally, mandibular bone had higher initial implant stability and physical properties than maxillary bone. Initial implant stability was higher in the anterior region than in the posterior. EM was higher in the posterior region than in the anterior; the reverse was true for cAD. Conclusions Of the properties evaluated, cAD had the highest correlation with initial implant stability (r=0.82). Both physical properties of bone and initial implant stability differed between regions of jawbone. (J Prosthet Dent 2009;101:306–318)

Aim: Determine whether periodontitis progression during pregnancy is associated with adverse birth outcomes. Methods: We used clinical data and birth outcomes from the Obstetrics and Periodontal Therapy Study, in which randomly selected women received periodontal treatment before 21 weeks of gestation (N=413) or after delivery (410). Birth outcomes were available for 812 women and follow-up periodontal data for 722, including 75 whose pregnancies ended 0.1) and mean birthweight (3295 versus 3184 g, p=0.11) did not differ significantly between women with and without disease progression. Gestational age and birthweight were not associated with change from baseline in percentage of tooth sites with bleeding on probing or between those who did versus did not progress according to a published definition of disease progression (p>0.05). Conclusions: In these women with periodontitis and within this study's limitations, disease progression was not associated with an increased risk for delivering a pre-term or a low birthweight infant.

The authors conducted a study to test the hypothesis that light-curing regimens affect depth of cure of clear versus opaque sealants.The authors light-cured samples of one clear and two opaque sealants at 20 seconds, 0 millimeters; 40 seconds, 0 mm; and 40 seconds, 2.2 mm (n = 5 each). They assessed the depth of cure with Knoop hardness at 0.5-mm increments five minutes and one hour after curing. The authors used analysis of variance.Curing regimens and sealant types affected the depth of cure. The clear sealant maintained a greater hardness than did the opaque sealants through a depth of 3 mm (P.001). A 20-second duration reduced the depth of cure for all sealants (P.001). The distance from the light source did not affect the cure depth of the clear sealant (P = .34), but it reduced the cure depth of the opaque sealants (P.05). Sealant hardness increased significantly one hour after light curing (P.001).A clear sealant cured deeper than did opaque sealants. Curing duration is crucial to achieve an adequate depth of cure. A 20-second duration may not suffice. Light source distance affected the depth of cure for the opaque sealants, but not for the clear sealant with sufficient curing duration.The authors advocate a curing duration of longer than 20 seconds to ensure thorough polymerization at the interface between the sealant and tooth. Insufficient curing could contribute to failure of the sealants, especially the opaque sealants, under clinical conditions that restrict the light tip position.

Background: Skin biopsy is an important procedure for the diagnosis of peripheral neuropathy. The main indicators of unmyelinated nerve involvement are decreased density and abnormal morphology of epidermal nerve fibers (ENFs). The suction skin blister is an alternative, less invasive method to visualize and quantify ENFs. The blister roof provides an integrated bird’s eye view of all ENFs within one tissue specimen. Objective: We compared the suction skin blister method to the punch skin biopsy for evaluation of ENFs. Methods: Twenty-five volunteers, 35 to 62 years old, without symptoms or history of peripheral neuropathy, and normal by neurologic examination and nerve conduction tests, were studied. One 3 mm punch biopsy and two 3 mm suction blister specimens were collected from the right foot and calf. Comparison between blister and biopsy ENF density was assessed by repeated measures analysis of covariance, accounting for age, gender, and specimen’s location. Results: The epidermal roof of the suction skin blister permitted detailed analyses of ENF density, morphology, and distribution across the epidermis and observation of ENF branching pattern. No systematic differences of ENF density were found between skin blisters and biopsies ( p = 0.29) or between pairs of blisters from the same location ( p = 0.15). ENF density was lower for older subjects ( p Conclusions: The suction skin blister method has potential as a diagnostic tool to investigate small fiber neuropathies. It is a minimally invasive and reliable technique, comparable to skin biopsy for determining epidermal nerve fiber density. BMI = body mass index; ENF = epidermal nerve fiber; PBS = phosphate buffered saline.

A recent clinical trial (Obstetrics and Periodontal Therapy [OPT] Study) demonstrated that periodontal therapy during pregnancy improved periodontal outcomes but failed to impact preterm birth. The present study evaluated seven target bacteria, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia (previously T. forsythensis), Prevotella intermedia, Campylobacter rectus, and Fusobacterium nucleatum, in subgingival dental plaque of pregnant women in the OPT Study and their association with birth outcomes.Pregnant women were randomly assigned to receive periodontal treatment before 21 weeks' gestation or after delivery. Subgingival plaque was sampled at baseline (13 to 16 weeks; 6 days of gestation) and at 29 to 32 weeks. We analyzed subgingival plaque samples from women who experienced fetal loss, delivered a live preterm infant (preterm women), or delivered a full-term infant (full-term women). Samples were analyzed using quantitative polymerase chain reaction. Associations between preterm birth and bacterial counts and percentages were tested using multiple linear regression.No significant differences were observed at baseline between preterm and full-term women for any measured bacterial species or group of species, after accounting for multiple comparisons. Changes in bacterial counts and proportions during pregnancy also were not associated with birth outcomes. In full-term and preterm women, periodontal therapy significantly reduced (P0.01) counts of all target species except for A. actinomycetemcomitans.In pregnant women with periodontitis, non-surgical periodontal therapy significantly reduced levels of periodontal pathogens. Baseline levels of selected periodontal pathogens or changes in these bacteria resulting from therapy were not associated with preterm birth.

Bayesian analyses frequently employ two-stage hierarchical models involving two-variance parameters: one controlling measurement error and the other controlling the degree of smoothing implied by the model's higher level. These analyses can be hampered by poorly identified variances which may lead to difficulty in computing and in choosing reference priors for these parameters. In this paper, we introduce the class of two-variance hierarchical linear models and characterize the aspects of these models that lead to well-identified or poorly identified variances. These ideas are illustrated with a spatial analysis of a periodontal data set and examined in some generality for specific two-variance models including the conditionally autoregressive (CAR) and one-way random effect models. We also connect this theory with other constrained regression methods and suggest a diagnostic that can be used to search for missing spatially varying fixed effects in the CAR model.

Statement of problem The opacity of the metal framework in metal ceramic restorations results in reduced light transmission through the tooth that diminishes the esthetics of the tooth. Purpose The purpose of this study was to investigate the color change that occurs apically to a metal ceramic restoration as a result of altering the metal framework design. Material and methods Color change relative to the unprepared tooth (ΔE) between various metal ceramic restorations was determined using computer imaging and CIELAB coordinates and compared to previously determined levels of clinical acceptability. Color change was evaluated by examining 2 conditions (the metal copings and the completed metal ceramic restorations), 4 framework designs (metal collar and porcelain margins with 0-mm, 1-mm, or 2-mm cutbacks), and 2 locations on the tooth apical to the margin of the restoration, using an imaging system developed at the Minnesota Dental Research Center for Biomaterials and Biomechanics. The data were analyzed statistically using repeated measures analysis of variance ( P =.05). Results For metal ceramic restorations there exists a significant ( P =.001) color change (ΔE) between all framework designs except for the 0-mm and 1-mm cutbacks. Color change (ΔE) in the location above the cemento-enamel junction was significantly greater ( P =.004) than below the cemento-enamel junction. Conclusions The framework design for metal ceramic restorations can affect the esthetics of the adjacent natural tooth. A minimum 2-mm facial cutback of the metal framework is necessary for there to be a significant difference in color change. (J Prosthet Dent 2008;99:468-476)

Statement of problem Initial implant stability has been used as an indicator for future osseointegration and whether an immediate/early loading protocol should be applied. However, differences in initial stability in relation to anatomical regions of jawbone have not been studied extensively because of the risks involved with stability measurements. Purpose The purpose of this study was to determine whether initial implant stability varies with anatomical regions of the jawbone. Material and methods Four pairs of edentulous maxillae and mandibles were retrieved from fresh human cadavers. Six implants (Biomet 3i) per pair were placed in different anatomical regions (maxillary anterior, right and left maxillary posterior, mandibular anterior, right and left mandibular posterior). Immediately after implant placement, initial implant stability was measured with a custom-made resonance frequency analyzer, a commercial resonance frequency analysis device (Osstell), and a mechanical tapping device (Periotest). All implant surgeries and initial stability measurements were performed within 72 hours of death to simulate a clinical setting. Repeated measures ANOVA (α=.05) and univariate correlation analyses were used to analyze the data. Results Mandibular implants had significantly higher initial stability than maxillary implants. Posterior maxillary implants were least stable. Stability was less buccolingually than mesiodistally. The measurements from 3 stability measuring devices were strongly associated with each other. Conclusions Initial implant stability varied among anatomical regions of jawbone. Rank of Periotest value and implant stability quotient (Osstell) had the highest correlation (r=-0.852). (J Prosthet Dent 2008;99:425-434)

Attachment loss (AL), the distance down a tooth's root that is no longer attached to surrounding bone by periodontal ligament, is a common measure of periodontal disease. In this article, we develop a spatiotemporal model to monitor the progression of AL. Our model is an extension of the conditionally autoregressive (CAR) prior, which spatially smooths estimates toward their neighbors. However, because AL often exhibits a burst of large values in space and time, we develop a nonstationary spatiotemporal CAR model that allows the degree of spatial and temporal smoothing to vary in different regions of the mouth. To do this, we assign each AL measurement site its own set of variance parameters and spatially smooth the variances with spatial priors. We propose a heuristic to measure the complexity of the site-specific variances, and use it to select priors that ensure parameters in the model are well identified. In data from a clinical trial, this model improves the fit compared to the usual dynamic CAR model for 90 of 99 patients' AL measurements.

The purpose of this study was to compare apical transportation, working-length changes, and instrumentation time by using nickel-titanium (Ni-Ti) rotary file systems (crown-down method) or stainless steel hand files (balanced-force technique) in mesiobuccal canals of extracted mandibular molars. The curvature of each canal was determined and teeth placed into three equivalent groups. Group 1 was instrumented with Sequence (Brasseler USA, Savannah, GA) rotary files, group 2 with Liberator (Miltex Inc, York, PA) rotary files, and group 3 with Flex-R (Union Broach, New York, NY) files. Pre- and postoperative radiographs were superimposed to measure loss of working length and apical transportation as shown by changes in radius of curvature and the long-axis canal angle. Sequence rotary files, Liberator rotary files, and Flex-R hand files had similar effects on apical canal transportation and changes in working length, with no significant differences detected among the 3 groups. Hand instrumentation times were longer than with either Ni-Ti rotary group, whereas the rotary NiTi groups had a higher incidence of fracture.

Introduction: Tooth movement through bone depends on local inflammatory reactions of the dentoalveolar tissues. Mechanical signals cause sensory afferent nerves to liberate inflammatory peptides around the teeth, creating local inflammation. Relationships between neurogenic inflammation and tooth movement are poorly understood. The objective of this study was to measure the differences in orthodontic tooth movement between rats treated with and without surgical transection of the maxillary nerve. Methods: Forty-two Sprague-Dawley rats were divided into 3 groups: (1) those with surgical transection of the maxillary nerve, (2) those with sham surgeries, and (3) those without surgery. After a 2-week healing period, a closed-coil spring appliance was activated to produce a 50 g mesial tipping force on the maxillary first molar. Diastema sizes distal to the first molar were measured in triplicate by using vinyl polysiloxane impression material and stone model pour-ups at 14 and 28 days of tooth movement. Images were captured and measured with a charge coupled device (CCD) microscope camera (Leeds Precision, Minneapolis, Minn) and Optimas measurement software (Media Cybernetics, Newburyport, Mass), respectively. Two-way repeated-measures ANOVA was used for statistical analysis. Results: Both weight and diastema size increased for all animals throughout the study. Although there were no significant differences between groups at any time point (log diastema, P = .43), the maxillary nerve transection surgery group had a significantly smaller increase in log diastema from 14 to 28 days than either the sham surgery or the nonsurgery group ( P = .045). Conclusions: This study suggests that surgical denervation causes little net effect on orthodontic tooth movement at these force levels.

Objective The objective of this study was to determine the utility of panoramic radiographs for detecting extracranial calcified carotid atheroma and carotid luminal stenosis. Study design Panoramic radiographs were obtained on 52 adult participants who had carotid ultrasound examination. Extent of carotid calcification and stenosis was determined by a cardiologist from ultrasound reports, which were considered gold standard assessments. A trained and calibrated oral and maxillofacial radiologist interpreted the radiographs for presence or absence of carotid calcifications. We examined the utility of panoramic radiographs to diagnose any carotid artery changes (diagnostic scheme 1) or only moderate to severe changes (scheme 2). Generalized estimating equations were used to account for clustering of observations within subjects. Results Under diagnostic schemes 1 and 2, radiographs had low sensitivity to detect carotid calcifications (31.1% and 25.0%, respectively) and stenoses (22.7% and 21.4%, respectively). Conclusions When compared to ultrasonography, panoramic radiography is not a reliable means to detect carotid artery calcifications or stenoses.

Measuring a statistical model's complexity is important for model criticism and comparison. However, it is unclear how to do this for hierarchical models due to uncertainty about how to count the random effects. The authors develop a complexity measure for generalized linear hierarchical models based on linear model theory. They demonstrate the new measure for binomial and Poisson observables modeled using various hierarchical structures, including a longitudinal model and an areal-data model having both spatial clustering and pure heterogeneity random effects. They compare their new measure to a Bayesian index of model complexity, the effective number pD of parameters (Spiegelhalter, Best, Carlin & van der Linde 2002); the comparisons are made in the binomial and Poisson cases via simulation and two real data examples. The two measures are usually close, but differ markedly in some instances where pD is arguably inappropriate. Finally, the authors show how the new measure can be used to approach the difficult task of specifying prior distributions for variance components, and in the process cast further doubt on the commonly-used vague inverse gamma prior. Une mesure de la complexite des modeles lineaires generalises hierarchiques Il importe de mesurer la complexite des modeles statistiques a des fins comparatives et critiques. Dans le cas des modeles hierarchiques, cette tâche est toutefois compliquee par une certaine ambiguite concernant le denombrement des effets aleatoires. Les auteurs s'inspirent de la theorie des modeles lineaires pour elaborer une mesure de complexite adaptee aux modeles lineaires generalises hierarchiques. Ils en illustrent l'interet dans le cas ou des donnees binomiales ou de Poisson sont modelisees a l'aide de diverses structures hierarchiques, y compris un modele longitudinal et un modele pour donnees geospatiales incluant une tendance au regroupement spatial et une heterogeneite pure sous forme d'effets aleatoires. Les auteurs comparent leur nouvelle mesure a un indice bayesien de la complexite d'un modele, a savoir le nombre effectif pd de parametres (Spiegelhalter, Best, Carlin & van der Linde 2002); les comparaisons sont faites dans les cas binomial et de Poisson sur la base de simulations et de deux cas concrets d'application. Les deux mesures sont generalement liees mais different substantiellement dans certaines circonstances ou l'indice pD parait inapproprie. Enfin, les auteurs montrent quel nouvel eclairage leur mesure apporte a l'epineux probleme du choix de lois a priori pour les composantes de la variance, ce qui les conduit a jeter un doute de plus sur l'emploi pourtant repandu de la loi vague de type gamma inverse dans ce contexte.

We present an approach to smoothing balanced, single–error term analysis of variance (ANOVA), descended from Smith, that also allows spatial, temporal, or spatiotemporal smoothing. The approach addresses unreplicated designs, masked contrasts in effects with many degrees of freedom, and subgroup analysis, demonstrated using a study of denture-lining materials. Our approach is Bayesian but can be viewed as a way to generate frequentist procedures. A simulation experiment compares four priors, unsmoothed ANOVA, and dropping nonsignificant interactions. Three priors have advantages when some interactions are absent; dropping nonsignificant interactions has serious flaws. We contrast our approach with the approaches of Nobile–Green and Gelman.

Attachment loss, the extent of a tooth's root (in millimeters) that is no longer attached to surrounding bone by periodontal ligament, is often used to measure the current state of a patient's periodontal disease and monitor disease progression. Attachment loss data can be analyzed using a conditionally autoregressive (CAR) prior distribution that smooths fitted values toward neighboring values. However, it may be desirable to have more than one class of neighbor relation in the spatial structure, so the different classes of neighbor relations can induce different degrees of smoothing. For example, we may wish to allow smoothing of neighbor pairs bridging the gap between teeth to differ from smoothing of pairs that do not bridge such gaps. Adequately modeling the spatial structure may improve the monitoring of periodontal disease progression. This article develops a two-neighbor-relation CAR model to handle this situation and presents associated theory to help explain the sometimes unusual posterior distr...

For individuals with temporomandibular joint (TMJ) disc displacement without reduction with limited mouth opening (closed lock), interventions vary from minimal treatment to surgery. In a single-blind trial, 106 individuals with TMJ closed lock were randomized among medical management, rehabilitation, arthroscopic surgery with post-operative rehabilitation, or arthroplasty with post-operative rehabilitation. Evaluations at baseline, 3, 6, 12, 18, 24, and 60 months used the Craniomandibular Index (CMI) and Symptom Severity Index (SSI) for jaw function and TMJ pain respectively. Using an intention-to-treat analysis, we observed no between-group difference at any follow-up for CMI (p ≥ 0.33) or SSI (p ≥ 0.08). Both outcomes showed within-group improvement (p < 0.0001) for all groups. The findings of this study suggest that primary treatment for individuals with TMJ closed lock should consist of medical management or rehabilitation. The use of this approach will avoid unnecessary surgical procedures.

Although the MR editing techniques that have traditionally been used for the measurement of glutathione (GSH) concentrations in vivo address the problem of spectral overlap, they suffer detriments associated with inherently long TEs. The purpose of this study was to characterize the sensitivity and specificity for the quantification of GSH concentrations without editing at short TE. The approach was to measure synthetically generated changes in GSH concentrations from in vivo stimulated echo acquisition mode (STEAM) spectra after in vitro GSH spectra had been added to or subtracted from them. Spectra from five test subjects were synthetically altered to mimic changes in the GSH signal. To account for different background noise between measurements, retest spectra (from the same individuals as used to generate the altered data) and spectra from five other individuals were compared with the synthetically altered spectra to investigate the reliability of the quantification of GSH concentration. Using STEAM spectroscopy at 7 T, GSH concentration differences on the order of 20% were detected between test and retest studies, as well as between differing populations in a small sample (n = 5) with high accuracy (R(2)0.99) and certainty (p ≤ 0.01). Both increases and decreases in GSH concentration were reliably quantified with small impact on the quantification of ascorbate and γ-aminobutyric acid. These results show the feasibility of using short-TE (1)H MRS to measure biologically relevant changes and differences in human brain GSH concentration. Although these outcomes are specific to the experimental approach used and the spectral quality achieved, this study serves as a template for the analogous scrutiny of quantification reliability for other compounds, methodologies and spectral qualities.

Meta-analysis has become a widely used tool to combine results from independent studies. The collected studies are homogeneous if they share a common underlying true effect size; otherwise, they are heterogeneous. A fixed-effect model is customarily used when the studies are deemed homogeneous, while a random-effects model is used for heterogeneous studies. Assessing heterogeneity in meta-analysis is critical for model selection and decision making. Ideally, if heterogeneity is present, it should permeate the entire collection of studies, instead of being limited to a small number of outlying studies. Outliers can have great impact on conventional measures of heterogeneity and the conclusions of a meta-analysis. However, no widely accepted guidelines exist for handling outliers. This article proposes several new heterogeneity measures. In the presence of outliers, the proposed measures are less affected than the conventional ones. The performance of the proposed and conventional heterogeneity measures are compared theoretically, by studying their asymptotic properties, and empirically, using simulations and case studies.

Network meta-analysis (NMA), also known as multiple treatment comparisons, is commonly used to incorporate direct and indirect evidence comparing treatments. With recent advances in methods and software, Bayesian approaches to NMA have become quite popular and allow models of previously unanticipated complexity. However, when direct and indirect evidence differ in an NMA, the model is said to suffer from inconsistency. Current inconsistency detection in NMA is usually based on contrast-based (CB) models; however, this approach has certain limitations. In this work, we propose an arm-based random effects model, where we detect discrepancy of direct and indirect evidence for comparing two treatments using the fixed effects in the model while flagging extreme trials using the random effects. We define discrepancy factors to characterize evidence of inconsistency for particular treatment comparisons, which is novel in NMA research. Our approaches permit users to address issues previously tackled via CB models. We compare sources of inconsistency identified by our approach and existing loop-based CB methods using real and simulated datasets and demonstrate that our methods can offer powerful inconsistency detection. Copyright © 2016 John WileySons, Ltd.

The aim of this study was to determine the association between more advanced stages of temporomandibular joint (TMJ) intra-articular disorders (“TMJ intra-articular status”), representing a transition from normal joint structure to TMJ disc displacement with and without reduction (DDwR and DDwoR) to degenerative joint disease (DJD), and patient-reported outcomes of jaw pain, function, and disability (“TMD impact”). This cross-sectional study included 614 cases from the RDC/TMD Validation Project with at least one temporomandibular disorder (TMD) diagnosis. TMJ intra-articular status was determined by 3 blinded, calibrated radiologists using magnetic resonance imaging and computed tomography as one of normal joint structure, DDwR, DDwoR, or DJD, representing the subject’s most advanced TMJ diagnosis. TMD impact was conceptualized as a latent variable consisting of 1) pain intensity (Characteristic Pain Index from the Graded Chronic Pain Scale [GCPS]), 2) jaw function (Jaw Functional Limitation Scale), and 3) disability (Disability Points from GCPS). A structural equation model estimated the association of TMJ intra-articular status with the latent measure TMD impact as a correlation coefficient in all TMD cases ( n = 614) and in cases with a TMD pain diagnosis ( n = 500). The correlations between TMJ intra-articular status and TMD impact were 0.05 (95% confidence interval [CI], −0.04 to 0.13) for all TMD cases and 0.07 (95% CI, −0.04 to 0.17) for cases with a pain diagnosis, which are neither statistically significant nor clinically relevant. Conceptualizing worsening of TMJ intra-articular disorders as 4 stages and characterizing impact from TMD as a composite of jaw pain, function, and disability, this cross-sectional study found no clinically significant association. Models of TMJ intra-articular status other than ours (normal structure → DDwR → DDwoR → DJD) should be explored.

This paper is about computations for linear mixed models having two variances, $\sigma^{2}_{e}$ for residuals and $\sigma^{2}_{s}$ for random effects, though the ideas can be extended to some linear mixed models having more variances. Researchers are often interested in either the restricted (residual) likelihood $\text{RL}(\sigma_{e}^{2},\sigma_{s}^{2})$ or the joint posterior $\pi(\sigma_{e}^{2},\sigma_{s}^{2}\,|\,y)$ or their logarithms. Both $\log\text{RL}$ and $\log\pi$ can be multimodal and computations often rely on either a general purpose optimization algorithm or MCMC, both of which can fail to find regions where the target function is high. This paper presents an alternative. Letting $f$ stand for either $\text{RL}$ or $\pi$, we show how to find a box $B$ in the $(\sigma_{e}^{2},\sigma_{s}^{2})$ plane such that ¶ 1. all local and global maxima of $\log f$ lie within $B$; ¶ 2. $\sup_{(\sigma_{e}^{2},\sigma_{s}^{2})\in B^{c}}\log f(\sigma_{e}^{2},\sigma_{s}^{2})\le \sup_{(\sigma_{e}^{2},\sigma_{s}^{2})\in B}\log f(\sigma_{e}^{2},\sigma_{s}^{2})-M$ for a prespecified $M>0$; and ¶ 3. $\log f$ can be estimated to within a prespecified tolerance $\epsilon$ everywhere in $B$ with no danger of missing regions where $\log f$ is large. ¶ Taken together these conditions imply that the $(\sigma_{e}^{2},\sigma_{s}^{2})$ plane can be divided into two parts: $B$, where we know $\log f$ as accurately as we wish, and $B^{c}$, where $\log f$ is small enough to be safely ignored. We provide algorithms to find $B$ and to evaluate $\log f$ as accurately as desired everywhere in $B$.

We investigate the cross channel effects of search engine advertising on Google.com on sales in brick and mortar retail stores. Obtaining causal and actionable estimates in this context is challenging: Brick and mortar store sales vary widely on a weekly basis; offline media dominate the marketing budget; search advertising and demand are contemporaneously correlated; and estimates have to be credible to overcome agency issues between the online and offline marketing groups. We report on a meta-analysis of a population of 15 independent field experiments, in which 13 well-known U.S. multi-channel retailers spent over $4 Million in incremental search advertising. In test markets category keywords were maintained in positions 1-3 for 76 product categories with no search advertising on these keywords in the control markets. Outcomes measured include sales in the advertised categories, total store sales and Return on Ad Spending. We estimate the average effect of each outcome for this population of experiments using a Hierarchical Bayesian (HB) model. The estimates from the HB model provides causal evidence that increasing search engine advertising on broad keywords on Google.com had a positive effect on sales in brick and mortar stores for the advertised categories for this population of retailers. There also was a positive effect on total store sales. Hence the increase in sales in the advertised categories was incremental to the retailer net of any sales borrowed from non-advertised categories. The total store sales increase was a meaningful improvement compared to the baseline sales growth rates. The average Return on Ad Spend (ROAS) is positive, does not breakeven on average although several retailers achieved or exceeded break-even based only on brick and mortar sales. We examine the robustness of our findings to alternative assumptions about the data specific to this set of experiments. Our estimates suggest online and offline are linked markets, that media planners should account for the offline effects in the planning and execution of search advertising campaigns, and that these effects should be adjusted by category and retailer. Extensive replication and a unique research protocol ensure that our results are general and credible.

Initial root canal treatment and the replacement of a single tooth with an implant are both viable treatment options, but various success rates have been reported for each treatment modality. This retrospective study compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes: success, survival, survival with subsequent treatment intervention and failure. Cross classifications/tabulations were analyzed using Pearson's chi2 test for association of the two classifications (endodontic vs implant and outcome). Polytomous regression with likelihood ratio tests were used in testing association with tooth location and outcome. Outcomes were as follows for implants and NSRCT respectively: success 73.5% and 82.1%; survival with no intervention 2.6% and 8.2%; survival with intervention 17.9% and 3.6%; and failure 6.1% and 6.1%. Location of the restoration in the mouth did not affect outcome. This study suggests that restored endodontically treated teeth and single tooth implant restorations have similar failure rates, although the implant group showed a longer average and median time to function and a higher incidence of postoperative complications requiring subsequent treatment intervention.

Chronic periodontitis (CP) risk is influenced by environmental and genetic factors. Using a case-control design, we tested for associations between CP and selected DNA sequence variations (single nucleotide polymorphisms [SNPs]) in or near genes coding for proteins that play a role in the pathogenesis of this disease.DNA was analyzed from 219 whites who were examined clinically. Cases (N=137) wereor=35 years of age with eight or more teeth havingor=5 mm of proximal clinical attachment loss. Controls (N=82) wereor=45 years of age with minimal or no proximal attachment loss or pocketing. Nine diallelic polymorphisms (gene and SNP descriptor) were studied in subjects: cytotoxic T-lymphocyte antigen-4 (CTLA-4, 49 AG), human beta-defensin-1 (DEFB1, 692 GA), intercellular adhesion molecule-1 (ICAM-1, 1548 AG), Fas ligand (fasL, -844 CT), inducible costimulator (ICOS, 3990 GT), interleukin-6 (IL-6, -174 GC), cysteine-cysteine chemokine receptor-5 (CCR5, 59653 CT), osteoprotegerin (OPG, 245 TG), and osteopontin (OPN, 707 CT). Genotypes were determined using an automated fluorogenic 5'-nuclease, polymerase chain reaction-based assay. Gender and smoking history (pack-years) were included as covariates in logistic regression analyses.Heavy smoking (10 pack-years) and male gender were significantly associated with disease (P0.001). For all SNPs tested, the allele frequencies and distributions of genotypes did not differ between cases and controls (P0.05). No unadjusted or adjusted odds ratios (comparing genotypes in cases versus controls) were significantly different than 1.0 (P0.05) under any additive, dominant, or recessive inheritance model.None of the SNPs tested were strongly associated with generalized severe chronic periodontitis in North American whites. A potentially more fruitful approach in future studies will be to test for associations between periodontitis and haplotype blocks constructed from either multiple SNPs in candidate gene regions or from panels of markers that span the entire genome.

The goal was to describe the association between post-traumatic stress disorder (PTSD) and in-service sexual harassment in a nationally representative sample of Department of Veterans Affairs PTSD disability applicants.The study was a cross-sectional survey.Of 4,918 eligible veterans, 3,337 (68%) returned surveys. Nonresponse bias appeared to be minimal. After adjustment for other reported traumas, women's reported in-service sexual harassment severity was significantly associated with PTSD symptom severity (p0.0001). The effect seen was about the same size as that seen for combat exposure among the men and for in-service sexual assault among the women. Men showed no association between in-service sexual harassment and PTSD (p = 0.33), although power was low for this test.Sexual harassment significantly contributed to female veterans' PTSD symptoms; its contribution to men's symptoms was unclear. We discuss mechanisms through which sexual harassment might affect PTSD symptom severity, including the possibility that sexual harassment sometimes meets the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, definition of a criterion A stressor.

Basketball coaches at all levels use shot charts to study shot locations and outcomes for their own teams as well as upcoming opponents. Shot charts are simple plots of the location and result of each shot taken during a game. Although shot chart data are rapidly increasing in richness and availability, most coaches still use them purely as descriptive summaries. However, a team's ability to defend a certain player could potentially be improved by using shot data to make inferences about the player's tendencies and abilities. This article develops hierarchical spatial models for shot-chart data, which allow for spatially varying effects of covariates. Our spatial models permit differential smoothing of the fitted surface in two spatial directions, which naturally correspond to polar coordinates: distance to the basket and angle from the line connecting the two baskets. We illustrate our approach using the 2003–2004 shot chart data for Minnesota Timberwolves guard Sam Cassell.

Impressions, dentures and other dental appliances may be contaminated with oral micro-flora or other organisms of varying pathogenicity from patient's saliva and blood. Several approaches have been tried to control the transmission of infectious organisms via dental impressions and because disinfection is less effective and has several drawbacks for impression characterization, several sterilization methods have been suggested. This study evaluated the reproducibility of rubber impressions after sterilization by different methods. Dimensional accuracy and wettability of two rubber impression materials (vinyl polysiloxane and polyether) were evaluated after sterilization by each of three well-known methods (immersion in 2% glutaraldehyde for 10 h, autoclaving and microwave radiation). Non-sterilized impressions served as control. The effect of the tray material on impression accuracy and the effect of topical surfactant on the wettability were also evaluated. One-way ANOVA with Dunnett's method was used for statistical analysis. All sterilizing methods reduced the reproducibility of rubber impressions, although not always significantly. Microwave sterilization had a small effect on both accuracy and wettability. The greater effects of the other methods could usually be overcome by using ceramic trays and by spraying impression surfaces with surfactant before pouring the gypsum mix. There was one exception: glutaraldehyde still degraded dimensional accuracy even with ceramic trays and surfactant. We conclude that a) sterilization of rubber impressions made on acrylic trays was usually associated with a degree of dimensional change; b) microwave energy seems to be a suitable technique for sterilizing rubber impressions; c) topical surfactant application helped restore wettability of sterilized impressions.

Objectives: The objective of this study was to determine if an association existed between periodontal disease and various systemic medical conditions and tobacco use. Material and Methods: The study design was a case-controlled, retrospective chart review. Patient charts (n=2006) were selected from more than 13,000 active patients attending the University of Minnesota dental clinics. These charts were examined to determine patient's self-reported systemic condition and smoking history. In addition, the number of missing teeth and bone loss were recorded. Two examiners collected the data. One examiner abstracted patient's medical history from the standard clinic medical questionnaire. The second examiner assessed the radiographs and dental charts to determine bone loss and number of missing teeth. Each examiner was blind to the findings of the other. Results: After adjusting for age, sex, diabetes and smoking (yes/no) status, seven conditions were significantly (p=0.0003–0.04) related to bone loss or number of missing teeth (vascular disease, heart surgery, vascular surgery, heart attack, thyroid problems, arthritis, stomach ulcers). From these conditions, thyroid problems and arthritis had a negative association with bone loss. Conclusions: These findings support the results from previous investigators that a number of systemic conditions and smoking are closely associated with missing teeth or bone loss.

A systematic review can be viewed as a study of studies, 1 done to understand why different studies of a given treatment gave varying results. One explanation – ie, one ‘‘independent variable’’ potentially explaining variation in study results – is the studies’ methodological quality, defined for the present purpose as internal validity, the extent to which potential for systematic error (bias) is minimized by careful study design, conduct, and analysis. Two broad approaches have been proposed to assess study quality and to construct such independent variables: the components approach, in which specific aspects of design, execution, and analysis are judged as adequate or inadequate; and quality scales, in which the components are given numerical scores, which are then summed to give a composite score. There is considerable empirical evidence about the association between study results and specific components of quality. Most commonly (but not always), lower quality on a component is associated with a larger estimated effect for a new treatment. Evidence regarding quality scales is much thinner, showing no association with study results except for the scale of Jadad et al. 2 This article concludes that assessing study quality is markedly hampered by poor reporting in journal articles; that summary scores from quality scales are inherently problematic; but that nonetheless a case can be made for routinely assessing certain components of study quality.

Background Self-etching adhesives are believed to prevent postoperative sensitivity when used under posterior resin-based composite restorations. The authors tested a twofold hypothesis: a self-etch, or SE, adhesive would result in less postoperative sensitivity than a total-etch, or TE, adhesive; an SE adhesive would result in poorer enamel marginal integrity than a TE adhesive. Methods Patients were selected on the basis of requiring Class I and II restorations in molars and premolars. The authors placed 30 restorations with the SE material (Clearfil SE Bond, Kuraray America, New York) and 36 restorations with Prime & Bond NT (Dentsply Caulk, Milford, Del.), which uses 34 percent phosphoric acid to etch enamel and dentin simultaneously. Preparations were of standard design, with all margins in enamel without beveling. Upon rubber dam isolation, the authors conditioned the enamel and dentin walls with the self-etching primer (for Clearfil SE Bond) or etched with the proprietary 34 percent phosphoric acid (for Prime & Bond NT), followed by application of the corresponding dentin adhesive. Teeth were restored with the proprietary hybrid resin-based composite indicated for posterior restorations: Clearfil AP-X for Clearfil SE Bond or Esthet•X Micro Matrix Restorative for Prime & Bond NT. The restored teeth were evaluated preoperatively and at two weeks, eight weeks and six months postoperatively for sensitivity to cold (ice), air and masticatory forces, as well as for marginal discoloration. Results Analysis of variance revealed no statistically significant differences in postoperative sensitivity between the SE and TE materials at any recall time. Marginal discoloration was rated as “absent” for all restorations at six months. Only one tooth displayed sensitivity to occlusal forces at six months. Conclusion The SE adhesive did not differ from the TE adhesive in regard to sensitivity and marginal discoloration. Clinical Implications Postoperative sensitivity may depend on the restorative technique rather than on the type of dentin adhesive used.

Statement of problem Numerous investigations have been done to determine the most accurate method to reproduce a dental arch. Investigations have used different definitive cast configurations, materials, and measuring techniques to evaluate dimensional change, leaving clinicians undecided as to the most accurate method to reproduce a dental arch. Purpose of study The purpose of this investigation was to evaluate the effect of impression tray selection on accuracy of reproductions of a dental arch using a 3-dimensional optical digitizer. Materials and methods Impressions were made of a stone cast of a dental arch using vinyl polysiloxane impression material in custom and stock impression trays (n=12). Custom trays, designed with full palatal coverage, were fabricated on a separate standard stone cast using 2 layers of pink baseplate wax as the spacer and tissue stops on 1 anterior tooth and both first molar teeth. Impressions were poured with type IV gypsum and allowed to set with the tray inverted (n=5) or not inverted (n=5). The standard cast and resulting casts were digitized using an optical digitizer. Custom software was used to align and process the 3-dimensional images created by the digitizer. Each image was superimposed onto the standard cast image, curves were created of the percent of points less than a defined distance between the 2 superimposed images, and the area under the curve was calculated. A weighted average area was calculated for each cast, and these values were analyzed using a 2-way ANOVA (α=.05). Results The main effect of tray type, laboratory setting technique, and the interaction between these 2 characteristics was analyzed. None of these effects was significant. Conclusion The differences in accuracy of reproductions of a dental arch, regardless of the impression and laboratory techniques, were not significant when evaluated using a 3-dimensional optical digitizer.

Purpose The purpose of this study was to count and to speciate Candida isolated from 2 resilient denture liners, Molloplast-B and MPDS-SL. Materials and methods A group of 20 patients each had 1 maxillary denture and 2 mandibular dentures fabricated. One mandibular denture was lined with Molloplast-B, and 1 was lined with MPDS-SL. Each denture was used for 3 months. At the end of the 3-month period, the mandibular denture was surrendered, and a 5 x 5-mm circular resilient liner sample was obtained from the tissue surface of the lingual flange. Samples were processed, and Candida was isolated and counted. Speciation of Candida was performed using CHROMagar Candida and API 20C AUX strips. Results Molloplast-B had, on average, 5 times as many CFU/sample as MPDSL-SL, but this difference was not significant (p = 0.26). A sign test gave a similar nonsignificant trend (p = 0.057). CHROMagar identified several Candida species, and confirmation was made using API 20C AUX strips. One patient was lost to follow-up. Of 19 Molloplast-B samples, 7 had no growth, 4 grew C. albicans, 3 grew C. parapsilosis, 2 grew C. glabrata, 1 grew C. tropicalis, 2 grew a Trichosporon spp., and 2 grew a nonidentifiable colony. The analogous counts for 19 MPDS-SL samples were 10, 4, 1, 3, 0, 1, and 1 (p = 0.45 for culture positively, exact McNemar test). Conclusions Candida growth on Molloplast-B was not significantly different from growth on MPDS-SL. Several yeast species were cultured from each material. The rates of culture-positive testing did not differ between the 2 resilient denture liners.

The purpose of this study was to examine how patients perceived the professionalism of University of Minnesota School of Dentistry students, faculty, and staff. Professionalism is defined by the authors as an image that will promote a successful relationship with the patient. Patients within comprehensive care clinics were asked to assess physical attributes and behaviors of the dental care providers using a questionnaire. The patients read statements dealing with characteristics of the dental care providers and responded as to whether they agreed, were neutral, or disagreed with the statement. The surveyed population consisted of 103 males and 97 females, 64 percent of whom lacked insurance coverage. Fifty-one percent of the patients were between the ages of forty-four and sixty-nine, but the overall age distribution was dispersed over a range of eighteen to one hundred. Our research found that all dental care providers displayed a professional appearance as well as behavior. The attire of the dental care provider affected the comfort and anxiety levels of patients, as did first impressions of both students and faculty. Most patients reported that students and faculty displayed effective time management and used appropriate language during the appointment. Finally, hairstyle, makeup, and jewelry appeared to have little effect on patients' opinions of the various dental care providers.

The universally accepted concept of delay-loaded dental implants has recently been challenged. This study hypothesizes that early loading (decreased implant healing time) leads to increased bone formation and decreased crestal bone loss. We used 17 minipigs to study implants under a controlled load, with non-loaded implants for comparison. Radiographic and histological assessments were made of the osseointegrated bone changes for 3 healing times (between implant insertion and loading), following 5 months of loading. The effect of loading on crestal bone loss depended on the healing time. Early loading preserved the most crestal bone. Delayed loading had significantly more crestal bone loss compared with the non-loaded controls (2.4 mm vs. 0.64 mm; P < 0.05). The histological assessment and biomechanical analyses of the healing bone suggested that loading and bioactivities of osteoblasts exert a synergistic effect on osseointegration that is likely to support the hypothesis that early loading produces more favorable osseointegration.

Mentally ill female veterans obtain a smaller proportion of their care from Department of Veterans Affairs (VA) facilities than mentally ill male veterans do, possibly because women are less likely than men to be service connected for psychiatric disabilities. "Service connected" veterans have documented, compensative conditions related to or aggravated by military service, and they receive priority for enrollment into the VA healthcare system.To see if there are gender discrepancies in rates of service connection for posttraumatic stress disorder (PTSD) and, if so, to see if these discrepancies could be attributed to appropriate subject characteristics (eg, differences in symptom severity or impairment).Mailed survey linked to administrative data. Claims audits were conducted on 11% of the sample.Randomly selected veterans seeking VA disability benefits for PTSD. Women were oversampled to achieve a gender ratio of 1:1.A total of 3337 veterans returned usable surveys (effective response rate, 68%). Men's unadjusted rate of service connection for PTSD was 71%; women's, 52% (P0.0001). Adjustment for veterans' PTSD symptom severity or functional impairment did not appreciably reduce this discrepancy, but adjustment for dissimilar rates of combat exposure did. Estimated rates of service connection were 53% for men and 56% for women after adjusting for combat exposure. This combat preference could not be explained by more severe PTSD symptoms or greater functional impairment.Instead of a gender bias in awards for PTSD service connection, we found evidence of a combat advantage that disproportionately favored men. The appropriateness of this apparent advantage is unclear and needs further investigation.

Information is scarce about Young's modulus of healing bone surrounding an implant. The purpose of this preliminary study is to quantify elastic properties of pig alveolar bone that has healed for 1 month around titanium threaded dental implants, using the nanoindentation method. Two 2-year-old Sinclair miniswine were used for the study. Nanoindentation tests perpendicular to the bucco-lingual cross section were performed on harvested implant-bone blocks using the Hysitron TriboScope III. Nomarski differential interference contrast microscopy was used to identify pyramidal indentation measurements that were from bone. Reduced moduli, averaged for all anatomical regions, were found to start low (6.17 GPa) at the interface and gradually increase (slope=0.014) to a distance of 150 microm (7.89 GPa) from the implant surface, and then flatten to a slope of 0.001 from 150 to 1500 microm (10.13 GPa). Mean reduced modulus and its relationship to distance did not differ significantly by anatomic location (e.g., coronal, middle, and apical third; P>/=0.28 for all relevant tests) at 1 month after implantation.

Spatial Poisson models for areal count data use nonstationary “intrinsic autoregressions,” also often referred to as “conditionally autoregressive” (CAR) models. Bayesian inference for these models has generally involved using single parameter updating Markov chain Monte Carlo algorithms, which often exhibit slow mixing (i.e., poor convergence) properties. These spatial models are richly parameterized and lend themselves to the structured Markov chain Monte Carlo (SMCMC) algorithms. SMCMC provides a simple, general, and flexible framework for accelerating convergence in an MCMC sampler by providing a systematic way to block groups of similar parameters while taking full advantage of the posterior correlation structure induced by the model and data. Among the SMCMC strategies considered here are blocking using different size blocks (grouping by geographical region), reparameterization, updating jointly with and without model hyperparameters, “oversampling” some of the model parameters, and “pilot adaptatio...