Restoratively guided orthodontic treatment: The pre-orthodontic bonding concept.

OBJECTIVE: Communication between the orthodontist and the restorative dentist has always been difficult due to the inability of the orthodontist to achieve the desired orthodontic goals with just words in a referral note. CLINICAL CONSIDERATIONS: A better method of communication is for the restorative dentist to create the ideal tooth anatomy either before or during orthodontic treatment to direct the orthodontic tooth movement. CONCLUSION: It is the purpose of this article to present a technique, which makes the pre-restorative orthodontic treatment both more accurate and more efficient. CLINICAL SIGNIFICANCE: It is very difficult for the orthodontist to move teeth into their correct positions when the teeth are anatomically incorrect due to attrition/erosion or due to developmental malformation. When the restorative dentist makes the teeth anatomically correct with either pre-orthodontic or intermediate orthodontic bonding, the orthodontist has the benefit of ideal tooth anatomy to finalize the tooth positions. This then allows the restorative dentist to create final restorations, which are ideal, both functionally and esthetically.

Extra credit for disruption: trend of disruption in radiology academic journals.

AIM: To identify the most disruptive publications, which are those that are cited more frequently than their own references, in academic radiology journals and their characteristics, such as the number of authors and relative time to publication. MATERIAL AND METHODS: A comprehensive literature search was undertaken to identify the 100 most disruptive publications in the field of radiology. Subsequently, statistical analysis was applied to establish the distribution of disruptive scores of the isolated publications using a non-parametric probability density function. The relation between disruptive scores and citation counts was then determined, with the aid of a correlation coefficient. Finally, data regarding any significant connection between disruption scores and time of publication, number of authors, and study design were examined. RESULTS: Analysing the top 100 papers in increments of 10-year periods showed no significant difference in the distribution of disruption scores over time. No correlation between an article's citation count and disruption score was established. Additionally, no significant relation between the number of authors/study design and disruption scores was identified. CONCLUSION: The disruption score highlights significant impact elements not entirely accounted for by citation count. Its potential benefit in assessing scientific impact should be contemplated.

Associations of hemoglobin and change in hemoglobin with risk of incident hip fracture in older men and women: the cardiovascular health study.

In a multi-site longitudinal cohort study, decreasing hemoglobin was associated with increased hip fracture risk in men. Anemia was associated with hip fracture in men and in African American women. Decreasing hemoglobin may be a marker of progressing bone fragility, making its serial measurement useful for fracture risk stratification. INTRODUCTION: Hematopoiesis and bone health are interdependent. Anemia has been associated with risk of fracture in humans. To further elucidate this relationship, we hypothesized that decreasing hemoglobin could indicate defective hematopoiesis and would also predict fracture risk. METHODS: We performed a prospective analysis from study baseline (1992) of the Cardiovascular Health Study, a multi-site longitudinal cohort study. A total of 4670 men and women, ages >65 years, who were able to consent and not institutionalized or wheelchair bound, had hemoglobin (Hb) measured in 1992. For 4006 subjects, Hb change from 1989 to 1992 was annualized and divided into sex-specific quartiles. Incident hip fractures were verified against Medicare claims data during a median follow-up of 11.8 years. RESULTS: Nested Cox proportional-hazard models estimated association of hip fracture with anemia (men Hb <13 g/dL, women Hb <12 g/dL) and separately, greatest Hb decrease (versus others). Anemia was associated with increased hip fracture risk in all men (HR 1.59; 95% CI 1.01-2.50) and African American women (HR 3.21; 95% CI 1.07-9.63). In men, an annualized Hb loss of >0.36 g/dL/year was associated with a higher risk of hip fracture (HR 1.67; 95% CI 1.10-2.54), which was lessened by anemia at the start of fracture follow-up (HR 1.53; 95% CI 0.99-2.39). CONCLUSIONS: Decreasing Hb may be an early marker for subsequent hip fracture risk in men, which may be less informative once an anemia threshold is crossed. Only African American women with anemia had increased hip fracture risk, suggesting a race difference in this relationship.

Biochemical markers of bone turnover and risk of incident hip fracture in older women: the Cardiovascular Health Study.

The relationships of osteocalcin (OC) and C-telopeptide of type I collagen (CTX) with long-term incidence of hip fracture were examined in 1680 post-menopausal women from a population-based study. CTX, but not OC, levels were associated with incident hip fracture in these participants, a relationship characterized by an inverted U-shape. INTRODUCTION: We sought to investigate the relationships of OC, a marker of bone formation, and CTX, a marker of bone resorption, with long-term incidence of hip fracture in older women. METHODS: We included 1680 women from the population-based Cardiovascular Health Study (mean [SD] age 74.5 [5.0] years). The longitudinal association of both markers with incidence of hip fracture was examined using multivariable Cox models. RESULTS: During a median follow-up of 12.3 years, 288 incident hip fractures occurred. Linear spline analysis did not demonstrate an association between OC levels and incident hip fracture. By contrast, increasing levels of CTX up to the middle-upper range were associated with a significantly greater risk of hip fracture (HR = 1.52 per SD increment, 95% CI = 1.10-2.09), while further increases were associated with a marginally non-significant lower risk (HR = 0.80 per SD increment, 95% CI = 0.63-1.01), after full adjustment for potential confounders. In analyses of quartiles, CTX exhibited a similar inverted U-shaped relationship with incident fracture after adjustment, with a significant association observed only for the comparison of quartile 3 to quartile 1 (HR = 1.63, 95% CI = 1.10-2.43). In a subset with available measures, both OC and CTX were inversely associated with bone mineral density of the hip. CONCLUSION: CTX, but not OC, levels were associated with incident hip fracture in post-menopausal women, a relationship characterized by an inverted U-shape. These findings highlight the complex relationship of bone turnover markers with hip fracture risk.

Association between subclinical thyroid dysfunction and change in bone mineral density in prospective cohorts.

BACKGROUND: Subclinical hyperthyroidism (SHyper) has been associated with increased risk of hip and other fractures, but the linking mechanisms remain unclear. OBJECTIVE: To investigate the association between subclinical thyroid dysfunction and bone loss. METHODS: Individual participant data analysis was performed after a systematic literature search in MEDLINE/EMBASE (1946-2016). Two reviewers independently screened and selected prospective cohorts providing baseline thyroid status and serial bone mineral density (BMD) measurements. We classified thyroid status as euthyroidism (thyroid-stimulating hormone [TSH] 0.45-4.49 mIU/L), SHyper (TSH < 0.45 mIU/L) and subclinical hypothyroidism (SHypo, TSH ≥ 4.50-19.99 mIU/L) both with normal free thyroxine levels. Our primary outcome was annualized percentage BMD change (%ΔBMD) from serial dual X-ray absorptiometry scans of the femoral neck, total hip and lumbar spine, obtained from multivariable regression in a random-effects two-step approach. RESULTS: Amongst 5458 individuals (median age 72 years, 49.1% women) from six prospective cohorts, 451 (8.3%) had SHypo and 284 (5.2%) had SHyper. During 36 569 person-years of follow-up, those with SHyper had a greater annual bone loss at the femoral neck versus euthyroidism: %ΔBMD = -0.18 (95% CI: -0.34, -0.02; I2 = 0%), with a nonstatistically significant pattern at the total hip: %ΔBMD = -0.14 (95% CI: -0.38, 0.10; I2 = 53%), but not at the lumbar spine: %ΔBMD = 0.03 (95% CI: -0.30, 0.36; I2 = 25%); especially participants with TSH < 0.10 mIU/L showed an increased bone loss in the femoral neck (%Δ BMD = -0.59; [95% CI: -0.99, -0.19]) and total hip region (%ΔBMD = -0.46 [95% CI: -1.05, -0.13]). In contrast, SHypo was not associated with bone loss at any site. CONCLUSION: Amongst adults, SHyper was associated with increased femoral neck bone loss, potentially contributing to the increased fracture risk.

The associations of subclinical atherosclerotic cardiovascular disease with hip fracture risk and bone mineral density in elderly adults.

In the absence of clinically recognized cardiovascular disease, increased carotid artery intimal medial thickness was associated with higher hip fracture risk in older adults, despite its association with higher bone mineral density (BMD). Low ankle brachial index and aortic wall thickness were not associated with fracture risk or BMD. INTRODUCTION: Clinically recognized cardiovascular disease (CVD) is associated with osteoporosis and hip fracture risk, but the relationship of subclinical atherosclerosis to bone health is not certain. METHODS: We followed 3385 participants from the Cardiovascular Health Study (mean age 74.7 ± 5.3 years) with a median time to fracture of 12.1 years who underwent baseline carotid artery and aortic wall ultrasound scanning and ankle brachial blood pressure index (ABI) determinations. A subset underwent bone mineral density (BMD) testing. RESULTS: There were 494 hip fractures during follow-up. Among persons without clinical CVD, an average standard-deviation increase in a composite score of maximal common and internal carotid artery intimal medial thickness (cIMT) was associated with increased risk of hip fracture [(HR 1.18 [1.04, 1.35]), even though cIMT was positively associated with BMD. Neither aortic wall thickness nor ABI were associated with hip fracture risk or BMD. Among participants with clinical CVD, cIMT and aortic wall thickness, but not ABI, were associated with increased hip fracture risk. CONCLUSION: Subclinical cIMT is associated with an increased risk of hip fractures despite being associated with increased BMD. This finding suggests that vascular health, even in its early stages, is linked to bone health, by pathways other than BMD.

The impact of the reserve military neurosurgeon: practice, community, and service.

OBJECTIVEPapers from 2002 to 2017 have highlighted consistent unique socioeconomic challenges and opportunities facing military neurosurgeons. Here, the authors focus on the reserve military neurosurgeon who carries the dual mission of both civilian and military responsibilities.METHODSSurvey solicitation of current active duty and reserve military neurosurgeons was performed in conjunction with the AANS/CNS Joint Committee of Military Neurosurgeons and the Council of State Neurosurgical Societies. Demographic, qualitative, and quantitative data points were compared between reserve and active duty military neurosurgeons. Civilian neurosurgical provider data were taken from the 2016 NERVES (Neurosurgery Executives Resource Value and Education Society) Socio-Economic Survey. Economic modeling was done to forecast the impact of deployment or mobilization on the reserve neurosurgeon, neurosurgery practice, and the community.RESULTSSeventy-five percent (12/16) of current reserve neurosurgeons reported that they are satisfied with their military service. Reserve neurosurgeons make significant contributions to the military's neurosurgical capabilities, with 75% (12/16) having been deployed during their career. No statistically significant demographic differences were found between those serving on active duty and those in the reserve service. However, those who served in the reserves were more likely to desire opportunities for improvement in the military workflow requirements compared with their active duty counterparts (p = 0.04); 92.9% (13/14) of current reserve neurosurgeons desired more flexible military drill programs specific to the needs of practicing physicians. The risk of reserve deployment is also borne by the practices, hospitals, and communities in which the neurosurgeon serves in civilian practice. This can result in fewer new patient encounters, decreased collections, decreased work relative value unit generation, increased operating costs per neurosurgeon, and intangible limitations on practice development. However, through modeling, the authors have illustrated that reserve physicians joining a larger group practice can significantly mitigate this risk. What remains astonishing is that 91.7% of those reserve neurosurgeons who were deployed noted the experience to be rewarding despite seeing a 20% reduction in income, on average, during the fiscal year of a 6-month deployment.CONCLUSIONSReserve neurosurgeons are satisfied with their military service while making substantial contributions to the military's neurosurgical capabilities, with the overwhelming majority of current military reservists having been deployed or mobilized during their reserve commitments. Through the authors' modeling, the impact of deployment on the military neurosurgeon, neurosurgeon's practice, and the local community can be significantly mitigated by a larger practice environment.

Association of DPP-4 activity with BMD, body composition, and incident hip fracture: the Cardiovascular Health Study.

There was no association of plasma DPP-4 activity levels with bone mineral density (BMD), body composition, or incident hip fractures in a cohort of elderly community-dwelling adults. INTRODUCTION: Dipeptidyl peptidase IV (DPP-4) inactivates several key hormones including those that stimulate postprandial insulin secretion, and DPP-4 inhibitors (gliptins) are approved to treat diabetes. While DPP-4 is known to modulate osteogenesis, the relationship between DPP-4 activity and skeletal health is uncertain. The purpose of the present study was to examine possible associations between DPP-4 activity in elderly subjects enrolled in the Cardiovascular Health Study (CHS) and BMD, body composition measurements, and incident hip fractures. METHODS: All 1536 male and female CHS participants who had evaluable DXA scans and plasma for DPP-4 activity were included in the analyses. The association between (1) BMD of the total hip, femoral neck, lumbar spine, and total body; (2) body composition measurements (% lean, % fat, and total body mass); and (3) incident hip fractures and plasma levels of DPP-4 activity were determined. RESULTS: Mean plasma levels of DPP-4 activity were significantly higher in blacks (227 ± 78) compared with whites (216 ± 89) (p = 0.04). However, there was no significant association of DPP-4 activity with age or gender (p ≥ 0.14 for both). In multivariable adjusted models, there was no association of plasma DPP-4 activity with BMD overall (p ≥ 0.55 for all) or in gender stratified analyses (p ≥ 0.23). There was also no association of DPP-4 levels and incident hip fractures overall (p ≥ 0.24) or in gender stratified analyses (p ≥ 0.39). CONCLUSION: Plasma DPP-4 activity, within the endogenous physiological range, was significantly associated with race, but not with BMD, body composition, or incident hip fractures in elderly community-dwelling subjects.

Incident atrial fibrillation and the risk of fracture in the cardiovascular health study.

In this prospective cohort of 4462 older adults, incident atrial fibrillation (AF) was not statistically significantly associated with subsequent risk of incident fracture. INTRODUCTION: AF is associated with stroke, heart failure, dementia, and death, but its association with fracture is unknown. Therefore, we examined the association of incident AF with the risk of subsequent fracture in the Cardiovascular Health Study (CHS) cohort. METHODS: Of the CHS participants aged ≥65 years, 4462 were followed between 1991 and 2009, mean follow-up 8.8 years. Incident AF was identified by annual study electrocardiogram (ECG), hospital discharge diagnosis codes, or Medicare claims. Fractures of the hip, distal forearm, humerus, or pelvis were identified using hospital discharge diagnosis codes or Medicare claims. We used Cox proportional hazard models to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association between incident AF (time-varying) and the risk of subsequent fracture. We also evaluated whether AF was associated with risk of sustaining a fall. RESULTS: Crude incident fracture rate was 22.9 per 1000 person-years in participants with AF and 17.7 per 1000 person-years in participants without AF. Individuals with incident AF were not at significantly higher risk of hip fracture (adjusted HR = 1.09, 95 % CI 0.83-1.42) or fracture at any selected site (adjusted HR = 0.97, 95 % CI 0.77-1.22) or risk of sustaining a fall (adjusted HR = 1.00, 95 % CI = 0.87-1.16) compared with those without AF. CONCLUSION: In this cohort of older, community-dwelling adults, incident AF was not shown to be associated with falls or hip or other fractures.

Human induced pluripotent stem cells as a research tool in Alzheimer's disease.

Human-induced pluripotent stem cells (iPSCs) offer a novel, timely approach for investigating the aetiology of neuropsychiatric disorders. Although we are starting to gain more insight into the specific mechanisms that cause Alzheimer's disease and other forms of dementia, this has not resulted in therapies to slow the pathological processes. Animal models have been paramount in studying the neurobiological processes underlying psychiatric disorders. Nonetheless, these human conditions cannot be entirely recapitulated in rodents. Human cell models derived from patients' cells now offer new hope for improving our understanding of the early molecular stages of these diseases, through to validating therapeutics. The impact of dementia is increasing, and a new model to investigate the early stages of this disease is heralded as an essential, new platform for translational research. In this paper, we review current literature using iPSCs to study Alzheimer's disease, describe drug discovery efforts using this platform, and discuss the future potential for this technology in psychiatry research.

Hemorrhage Rate After External Ventricular Drain Placement in Subarachnoid Hemorrhage: Time to Heparin Administration.

OBJECTIVE: The use of antiplatelet or anticoagulants has previously been shown to increase hemorrhagic complications of ventricular catheterization. Although heparin use 24 h after ventriculostomy appears safe, the safety of heparin immediately (within 4 h) after ventriculostomy is unknown. The objective of this study was to assess the safety of heparin immediately (within 4 h) after ventriculostomy in subarachnoid hemorrhage (SAH) patients undergoing endovascular treatment. PATIENTS AND METHODS: This is a retrospective cohort study of 46 patients with aneurysmal SAH secondary to aneurysm rupture who required ventriculostomy. Post-ventriculostomy imaging was carefully reviewed for tract hemorrhaging. Timing of heparinization was noted. Early heparinization was within 4 h after ventriculostomy, and intermediate heparinization was between 4 and 24 h after ventriculostomy. RESULTS: Overall, the tract hemorrhage rate was 26.1% for the study cohort-mostly grade I tract hemorrhages-consistent with the existing literature. The tract hemorrhage rate in the early (<4 h) heparin group was a remarkable 58.8%. The hemorrhages were also notably larger in the early (<4 h) heparin group. CONCLUSION: Although heparin appears to be safe after 4 h, immediate heparinization (within 4 h) after ventriculostomy significantly increases the odds of tract hemorrhage. Additional time should be afforded between ventriculostomy and heparinization to avoid potentially devastating external ventricular drain tract hemorrhage. It is advisable to wait a sufficient time (at least 4 h) after ventriculostomy before embarking on endovascular treatment of ruptured aneurysms.

Soluble CD14 and fracture risk.

UNLABELLED: Soluble CD14 (sCD14) is an inflammatory marker associated with osteoclasts. Using Cox proportional hazards models, we found a positive association between plasma levels of sCD14 and risk of incident fracture among participants in the Cardiovascular Health Study. sCD14 may be useful in identifying those at risk for fracture. INTRODUCTION: Soluble CD14, a proinflammatory cytokine, is primarily derived from macrophages/monocytes that can differentiate into osteoclasts. The purpose of this study was to examine the relationship between sCD14 levels and osteoporotic fractures. METHODS: In the Cardiovascular Health Study, 5462 men and women had sCD14 levels measured at baseline. Incident hip fractures (median follow-up time 12.5 years) and incident composite fractures (defined as the first hip, pelvis, humerus, or distal radius fracture, median follow-up 8.6 years) were identified from hospital discharge summaries and/or Medicare claims data. Cox proportional hazards models were used to model the association between sCD14 levels and time to incident hip or composite fracture, overall and as a function of race and gender. RESULTS: In unadjusted models, there was a positive association between sCD14 levels (per 1 standard deviation increase, i.e., 361.6 ng/mL) and incident hip (HR, 1.26; 95 % CI, 1.17, 1.36) and composite (HR, 1.20; 95 % CI, 1.12, 1.28) fractures. When models were fully adjusted for demographics, lifestyle factors, and medication use, these associations were no longer significant. However, in whites, the association of sCD14 levels with hip fractures remained significant in fully adjusted models (HR, 1.11; 95 % CI, 1.01-1.23). Associations of sCD14 levels with hip and composite fracture did not differ between men and women. CONCLUSIONS: In this large cohort of community-dwelling older adults, higher sCD14 levels were associated with an increased risk of incident hip fractures in whites.

Systemic markers of microvascular disease and bone mineral density in older adults : The cardiovascular health study.

Here we report that abnormal brain white matter and, to a lesser extent, albuminuria are associated with reduced bone mineral density in the hip, spine, and total body in men and women. These findings may explain the increased hip fracture risk reported in some studies in association with microvascular disorders. INTRODUCTION: Markers of microvascular disease have been individually associated with increased risk of osteoporotic fractures in some studies. Here, we examine whether these markers are associated with reduced bone mineral density (BMD) individually and together. METHODS: BMD testing using dual x-ray absorptiometry of the hip, lumbar spine, and total body was performed in 1473 participants from the Cardiovascular Health Study (mean age ~ 78 years): 1215 were assessed for urinary albumin-creatinine ratio, 944 for abnormal white matter disease (AWMD) by brain MRI, and 541 for retinal vascular disease with fundus photographs. Linear regression models were used to evaluate the cross-sectional association of each marker with BMD accounting for potentially confounding factors. RESULTS: AWMD was associated with lower hip, spine, and total body BMD in women (ß -3.08 to -4.53; p < 0.01 for all) and lower hip and total body BMD in men (ß -2.90 to -4.24; p = 0.01-0.03). Albuminuria was associated with lower hip (ß -3.37; p = .05) and total body (ß -3.21; p = .02) BMD in men, but not in women. The associations of AWMD and albuminuria with BMD persisted with mutual adjustment and appeared to be additive to each other. Retinal vascular disease was not associated with BMD in men or women. CONCLUSION: AWMD and, to a lesser extent, albuminuria were independently associated with lower BMD, suggesting that microvascular disease may play a role in the pathogenesis of reduced BMD. These findings need to be confirmed by longitudinal studies.

Novel loci associated with usual sleep duration: the CHARGE Consortium Genome-Wide Association Study.

Usual sleep duration is a heritable trait correlated with psychiatric morbidity, cardiometabolic disease and mortality, although little is known about the genetic variants influencing this trait. A genome-wide association study (GWAS) of usual sleep duration was conducted using 18 population-based cohorts totaling 47 180 individuals of European ancestry. Genome-wide significant association was identified at two loci. The strongest is located on chromosome 2, in an intergenic region 35- to 80-kb upstream from the thyroid-specific transcription factor PAX8 (lowest P=1.1 × 10(-9)). This finding was replicated in an African-American sample of 4771 individuals (lowest P=9.3 × 10(-4)). The strongest combined association was at rs1823125 (P=1.5 × 10(-10), minor allele frequency 0.26 in the discovery sample, 0.12 in the replication sample), with each copy of the minor allele associated with a sleep duration 3.1 min longer per night. The alleles associated with longer sleep duration were associated in previous GWAS with a more favorable metabolic profile and a lower risk of attention deficit hyperactivity disorder. Understanding the mechanisms underlying these associations may help elucidate biological mechanisms influencing sleep duration and its association with psychiatric, metabolic and cardiovascular disease.

Perineal pain secondary to tethered cord syndrome: retrospective review of single institution experience.

OBJECT: Tethered cord syndrome (TCS) encompasses a spectrum of neurological dysfunction related to excessive tension on the distal spinal cord resulting in anatomic deformation and metabolic disturbance. Symptoms typically manifest as back/leg pain, neurogenic bladder dysfunction, constipation, sphincter abnormalities, and scoliosis. To date, among the least well-described symptoms of TCS is pain or hypersensitivity in the perineal region. The authors reviewed their experience with spinal cord detethering to identify and further characterize those who present with perineal pain or hypersensitivity. METHODS: Cases of spinal cord detethering at a single institution were retrospectively reviewed. Patients were initially identified by procedural codes. Cases were reviewed for presenting symptoms, specifically perineal pain or hypersensitivity. Magnetic resonance image (MRI) findings, clinical outcome, and length of follow-up were also noted. RESULTS: Of the 491 patients identified, seven patients (1.4%) were identified as having preoperative perineal pain or hypersensitivity. All of these patients had complete resolution of perineal pain/hypersensitivity at the time of last follow-up. Furthermore, five (71%) of these patients experienced resolution of all initial symptoms. CONCLUSION: Perineal pain or hypersensitivity can be an important symptom of spinal cord tethering. Spinal cord detethering may result in a good outcome and relief of perineal pain or hypersensitivity.

Relationships Among Rheological, Sensory Texture, and Swallowing Pressure Measurements of Hydrocolloid-Thickened Fluids.

The objective of this study was to examine the relationships among three categories of measurements (rheological, sensory texture, and swallowing pressure) from fluids thickened to two different viscosities with 15 different hydrocolloids. Fluids at viscosities of 300 and 1500 cP (at 30 s(-1)) were targeted because these are the viscosities corresponding to the barium standards used in radiographic dysphagia diagnosis. Within the low viscosity (nectar) fluids (300 cP), the sensory properties thickness, stickiness, adhesiveness, mouth coating, and number of swallows were highly positively correlated with each other and highly positively correlated with the flow behavior index, n value (an indicator of shear-thinning behavior). Within the higher viscosity (thin honey) fluids (1500 cP), the sensory textures of adhesiveness, stickiness, mouth coating, and number of swallows correlated positively with rheological measures of n value. Swallowing pressures measured in the anterior oral cavity correlated negatively with the consistency coefficient k [shear stress/(shear rate) (n) ]. Samples that were more shear thinning (lower n values, higher k values) were generally perceived as less thick, with less adhesive properties (stickiness, adhesiveness, mouthcoating, and number of swallows). This information can be useful for selecting thickeners for people with dysphagia. A desirable thickener for many dysphagic patients would be one that allowed for a safe swallow by being viscous enough to reduce airway penetration, yet pleasant to drink, having the minimal perceived thickness and mouthcoating associated with greater shear thinning.

Management of impacted wisdom teeth: teaching of undergraduate students in UK dental schools.

INTRODUCTION: Wisdom tooth removal is one of the most common oral surgical procedures performed across the world. The aim of this study was to gauge the teaching and training of impacted wisdom teeth in undergraduate dental programmes across the UK. The objectives were to identify consistencies and variations in theoretical instructions and clinical training as well as approaches to management of impacted wisdom teeth. METHODS: This was a cross-sectional survey utilising an online questionnaire. A purposefully designed pro forma with open- as well as closed-ended questions was used. The questionnaire was hosted online on the school's blackboard academic suite (Emily). Prior to conducting the study, approval was gained from the Research and Ethics Committee, and all the ethical principles pertaining to data protection were strictly followed. E-mail invitations were sent to oral surgery leads in all dental schools in the UK. The participants were provided with an information sheet, and an informed consent was obtained. The participants were invited by e-mail to complete the questionnaire online voluntarily. RESULTS: A total of 16 dental schools offering an undergraduate course in dentistry in the UK, 13 responded positively. (response rate = 81.25%). In majority of dental schools, this subject is taught in the 4th and 5th years. A pre-clinical competency on phantom heads is a requirement in six schools, whilst only one school requires the students to pass a clinical competency. The clinical exposure of students to wisdom tooth surgery is quite variable. Although the dental schools are fairly consistent in their teaching with regard to the indications for surgical intervention, diagnostic/treatment modalities as well as the post-operative care, interesting variations were also observed. CONCLUSIONS: This study, perhaps the first of its kind, provides useful insights into management of impacted wisdom teeth, as taught in the undergraduate dental programmes across the UK.

A Case Against the Implant.

It is incumbent upon our profession to reevaluate our preference for routinely replacing a missing single maxillary incisor, especially a maxillary lateral incisor, with a dental implant in a young adult. The dental literature is replete with beautiful restorative results using implants in this area, but there is minimal discussion regarding the long-term consequences of this treatment. The maxillary lateral incisor is one of the most commonly missing teeth due to agenesis, and it is also one of the most common teeth to be lost due to trauma in the developing child.1 Therefore, the decision for replacement must be made with the long-term in mind, as these restorations are commonly placed between ages 18 and 21 and must serve the patient for many decades. There are several reasons that implants can be associated with complications or even fail, including the following: (1) Continued craniofacial growth, which has a predominant anterior and vertical component and has been shown to occur in the maxilla, resulting in the apparent submersion of the implant crown as the natural teeth move incisally in relation to the implant2,3-there is no evidence that this can be predicted, let alone how far into the future it may happen; (2) peri-implantitis, which has a patient-level prevalence estimate of nearly 25% according to the findings of a recent systematic review;4 (3) thinning and recession of the peri-implant mucosa due to poor implant placement, inadequate prosthetic management, and/or poor case selection, often resulting in compromised esthetics and a predisposition for the onset and progression of peri-implant diseases; and (4) mechanical failure of the implant, abutment screw, transmucosal abutment, and/or crown. Clinicians should also keep in mind that, once an implant is placed in the anterior maxilla, it precludes the possibility for palatal expansion in the adult patient because the space created by the expansion cannot be redistributed orthodontically. Canine substitution is one traditional method for replacement of the missing maxillary lateral incisor. It is still a viable option when the canine tooth has an acceptable shape and color, and the occlusion will not be compromised by the substitution.5 Additionally, the bonded single-wing zirconia bridge has become a primary treatment option.6 Zirconia has the strength of metal and beauty of porcelain, which makes it an ideal substrate for a bonded bridge. The literature has demonstrated the long-term success of this replacement option for the missing maxillary incisor.7 There are clearly many potential long-term disadvantages associated with replacing a single missing maxillary incisor with an implant in young adults. We should be prescribing the least-invasive treatment option for the replacement of these teeth. Therefore, when treatment-planning for a missing maxillary incisor in a young adult, alternatives to implant therapy-such as the bonded single-wing zirconia bridge and canine substitution-should be the primary treatment options. The implant should only be considered as a secondary treatment when the other options are not viable or have previously failed.

Altered regional cardiac wall mechanics are associated with differential cardiomyocyte calcium handling due to nebulette mutations in preclinical inherited dilated cardiomyopathy.

Nebulette (NEBL) is a sarcomeric Z-disk protein involved in mechanosensing and force generation via its interaction with actin and tropomyosin-troponin complex. Genetic abnormalities in NEBL lead to dilated cardiomyopathy (DCM) in humans and animal models. The objectives of this study are to determine the earliest preclinical mechanical changes in the myocardium and define underlying molecular mechanisms by which NEBL mutations lead to cardiac dysfunction. We examined cardiac function in 3-month-old non-transgenic (non-Tg) and transgenic (Tg) mice (WT-Tg, G202R-Tg, A592E-Tg) by cardiac magnetic resonance (CMR) imaging. Contractility and calcium transients were measured in isolated cardiomyocytes. A592E-Tg mice exhibited enhanced in vivo twist and untwisting rate compared to control groups. Ex vivo analysis of A592E-Tg cardiomyocytes showed blunted calcium decay response to isoproterenol. CMR imaging of G202R-Tg mice demonstrated reduced torsion compared to non-Tg and WT-Tg, but conserved twist and untwisting rate after correcting for geometric changes. Ex vivo analysis of G202R-Tg cardiomyocytes showed elevated calcium decay at baseline and a conserved contractile response to isoproterenol stress. Protein analysis showed decreased α-actinin and connexin43, and increased cardiac troponin I phosphorylation at baseline in G202R-Tg, providing a molecular mechanism for enhanced ex vivo calcium decay. Ultrastructurally, G202R-Tg cardiomyocytes exhibited increased I-band and sarcomere length, desmosomal separation, and enlarged t-tubules. A592E-Tg cardiomyocytes also showed abnormal ultrastructural changes and desmin downregulation. This study showed distinct effects of NEBL mutations on sarcomere ultrastructure, cellular contractile function, and calcium homeostasis in preclinical DCM in vivo. We suggest that these abnormalities correlate with detectable myocardial wall motion patterns.