A reconstructed computerized tomographic comparison of Ni-Ti rotary GT files versus traditional instruments in canals shaped by novice operators

AIM: The aim of this study was to compare the effects of preparation with conventional stainless steel Flexofiles and Gates Glidden burs versus nickel-titanium GT rotary files in the shaping of mesial root canals of extracted mandibular molars. METHODOLOGY: A total of 54 canals from 27 mesial roots of mandibular molar teeth were prepared using one of two methods by novice dental students. One canal in each root was prepared by a crown-down approach. utilizing stainless steel Flexofiles and Gates Glidden burs. The other canal was prepared using nickel-titanium GT rotary files in a crown-down fashion as recommended by the manufacturer. Preoperative CT scans of each root were recorded and 50 canal specimens were available for postoperative comparisons. Following canal shaping, postoperative scans were superimposed on the original images. Changes in canal area, canal transportation and thickness of remaining root structure at strategic levels of the root were analyzed. The time taken for each method was also noted. RESULTS: At the coronal and mid-root coronal one-third sections, the rotary GT files produced a significantly smaller postoperative canal area (P < 0.05). In the mid-root sections there was significantly less transportation of the root canal toward the furcation, and less thinning of the root structure with GT files compared to the stainless steel files (P < 0.05). Overall, there was greater conservation of structure coronally and more adequate shape in the mid-root level. The GT rotary technique was significantly faster than the stainless steel hand-held file technique (P < 0.0001). Two GT instruments fractured during the study. CONCLUSIONS: Under the conditions of this study, novice dental students were able to prepare curved root canals with Ni-Ti GT rotary files with less transportation and greater conservation of tooth structure, compared to canals prepared with hand instruments. The rotary technique was significantly faster.     

Selling your practice at retirement. Are there problems ahead?

BACKGROUND: The dental work force is maturing as fewer dentists enter practice. In this article, the authors considered two questions: "Will demographic trends in the numbers of dentists leaving and entering practice place additional downward pressure on the value of dental practices?" and "How important is the sale of practices for retirement income?" METHODS: To address the first question, the authors estimated the number of retirees using 62 years as retirement age, and they projected the number of graduates using current trends of first-year enrollments. To address the second question, the authors used the ADA's 1995 Survey of Current Issues in Dentistry, which addressed dentists' retirement savings. RESULTS: The annual rate of dentists' retiring is projected to be 2.1 percent compared with 1 percent among dentists projected to graduate during the period of 2001-2020. Although dental practice value is 40 percent or more of practitioners' reported retirement savings, the majority of dentists report that they do not depend on the sale of their practices to finance their retirement. CONCLUSIONS: In the next 20 years, the number of retirees will grow faster than the number of graduates, exerting a downward pressure on the value of dental practices. PRACTICE IMPLICATIONS: To successfully plan for retirement, dentists need to carefully assess their target levels of retirement savings, the time of their retirement and their dependence on the sales of their practices.     

Dentists' participation in capitation and preferred provider organization dental plans

BACKGROUND: In 1998, the American Dental Association Survey Center conducted a telephone and mail survey of U.S dentists in private practice in an effort to determine the extent of dentists' participation in capitation and preferred provider organization, or PPO, dental plans and the characteristics of dentists who participate in those plans. METHODS: An initial phone screening survey was conducted with a random sample of 11,550 dentists in private practice. Dentists who indicated that they participated in capitation or PPO dental plans received a follow-up mail survey asking specific questions concerning these two types of dental plans. RESULTS: Almost one-half of responding dentists indicated that they participated in either capitation or PPO dental plans. However, far more dentists reported participating in PPO dental plans than in capitation dental plans. The majority of participating dentists' patients were reported to be fee-for-service patients. CONCLUSIONS: Dentists' participation in PPO dental plans generally increased from that indicated in previous surveys, though participation in capitation plans declined. There was some regional and demographic variation in participation in these dental plans, but such differences were not large. Pricing and concerns about quality of care continue to be the primary concerns of nonparticipating dentists. PRACTICE IMPLICATIONS: Dentists reporting participation in PPO dental plans are becoming more common, but such plans still do not cover the majority of participating dentists' patients. A large percentage of nonparticipating dentists cite pricing and concerns about quality care as reasons for not joining these plans.     

Racial/ethnic variations of practicing dentists

BACKGROUND: In recent years, the dental school population has changed from being predominantly white male to a more diverse racial and ethnic makeup. Noting this change in the student population, the American Dental Association undertook an in-depth study of the various racial/ethnic groups. METHODS: Questionnaires were sent to approximately 8,000 dentists nationwide. Samples were drawn for each of the following racial/ethnic groupings: white, black, Hispanic, Native American and Asian. The survey instrument asked questions about personal characteristics, work and private practice issues, household and practice income, and patient characteristics; it also asked for dentists' opinions. A final adjusted response rate of 57.0 percent was achieved. RESULTS: The majority of all dentists responded that they were "very satisfied" with their profession, but the survey found variations in patient mix, employment history and provision of free or discounted care. CONCLUSIONS: The survey examined dentists by race/ethnicity to identify differences and similarities. Cultural and ethnic minorities are the fastest growing segment of the U.S. population. As the profession becomes more diverse, practice patterns will affect the overall dental profession. PRACTICE IMPLICATIONS: Dentists' racial/ethnic backgrounds may change the provision of care as patient mix varies, with each dentist group treating a specific group of patients in regard to family income, racial/ethnic background and subgroups for whom they offer free or reduced-rate dental care.     

Enhanced fluoride uptake from mouthrinses

It has been shown in laboratory and animal studies that tooth enamel becomes considerably more reactive toward low levels of fluoride after receiving pre-treatment which forms dicalcium phosphate dihydrate (DCPD) in the enamel as an intermediate. This in vitro study was undertaken to determine the effect on human enamel fluoride uptake of incorporating DCPD-forming rinses into a conventional fluoride rinsing program. In one group, enamel samples received a one-minute rinse with 0.2% NaF each day for 20 days. Samples in the second group were treated identically, except that they were also given a one-minute DCPD-forming rinse prior to the first, sixth, eleventh, and sixteenth fluoride rinses. At the end of the rinsing program, all samples were washed in 1 M KOH to remove labile fluorides. The enamel biopsy data showed that the fluoride uptake resulting from 0.2% NaF alone was not statistically significant, whereas uptake produced by the DCPD-forming plus NaF rinses was significant. The results suggest that the DCPD-forming rinse may improve the efficacy of fluoride rinse programs.     

Variability of magnetoencephalographic sensor sensitivity measures as a function of age,brain volume and cortical area

Objective

To assess the feasibility and appropriateness of magnetoencephalography (MEG) for both adult and pediatric studies, as well as for the developmental comparison of these factors across a wide range of ages.

Methods

For 45 subjects with ages from 1 to 24 years (infants, toddlers, school-age children and young adults), lead fields (LFs) of MEG sensors are computed using anatomically realistic boundary element models (BEMs) and individually-reconstructed cortical surfaces. Novel metrics are introduced to quantify MEG sensor focality.

Results

The variability of MEG focality is graphed as a function of brain volume and cortical area. Statistically significant differences in total cerebral volume, cortical area, MEG global sensitivity and LF focality are found between age groups.

Conclusions

Because MEG focality and sensitivity differ substantially across the age groups studied, the cortical LF maps explored here can provide important insights for the examination and interpretation of MEG signals from early childhood to young adulthood.

Significance

This is the first study to (1) investigate the relationship between MEG cortical LFs and brain volume as well as cortical area across development, and (2) compare LFs between subjects with different head sizes using detailed cortical reconstructions.     

Guyon Canal Syndrome: lack of management in a case of unresolved handlebar palsy

Objective:

To present the clinical diagnostic features including management of Guyon canal syndrome in a case with unresolved sensory deficits in a young female cyclist.

Clinical Presentation:

After 14 days of cycling across Canada, a 23-year old female experienced sensory loss, followed by atrophy and a “claw” hand appearance of her left hand.

Intervention and Outcome:

Treatment included cervical chiropractic manipulation, soft tissue therapy and the use of cycling gloves. Seven years after the initial injury a lack of sensation in the ulnar nerve distribution of her left hand has persisted.

Discussion:

This case demonstrates that a lack of proper management can lead to permanent sensory loss and is worth highlighting. Various therapists evaluated the patient’s symptoms and provided minimal care. No diagnosis was given, nor were appropriate measures taken for her to understand the risks of continuing to ride.

Summary:

Although treatment for Guyon Canal Syndrome can be as easy as cessation from cycling until symptoms subside, other treatment options could be utilized to help manage ulnar nerve compression injuries in cyclists.     

CAGS AND ACS EVIDENCE BASED REVIEWS IN SURGERY. 49: Is a diverting loop ileostomy and colonic lavage an alternative to colectomy for the treatment of severe Clostridium difficile–associated disease?

Objective: To determine whether a colon-sparing diverting ileostomy with colonic lavage reduces mortality in patients with severe Clostridium difficile–associated disease (CDAD) when compared with colectomy. Design: Retrospective cohort study. Setting & patients: Forty-two patients with diagnosed severe, complicated CDAD who were treated at the University of Pittsburgh Medical Center or VA Pittsburgh Health Care System between June 2009 and January 2011 with diverting loop ileostomy and colonic lavage (warmed polyethylene glycol 3350/electrolyte solution via the ileostomy and postoperative antegrade instillation of vancomycin flushes via the ileostomy). Patients were compared with a historical control group of 42 patients who had a colectomy. Main outcome: Resolution of CDAD. Results: There was no significant difference in age, sex, pharmacologic immuno-suppression and Acute Physiology and Chronic Health Evaluation-II (APACHE-II) scores between the current cohort and historical controls. In the ileostomy group, surgery was performed laparoscopically in 35 patients (83%). This treatment strategy resulted in reduced mortality compared with the historical population (19% v. 50%; odds ratio [OR] 0.24, p = 0.006). Preservation of the colon was achieved in 39 of 42 patients (93%). Conclusion: Loop ileostomy and colonic lavage are an alternative to colectomy in the treatment of severe, complicated CDAD, resulting in reduced morbidity and preservation of the colon.     

Barriers to recruiting ethnic minorities to mental health research: a systematic review

Disparities in the prevalence of mental illness are widely reported for people from ethnic minorities. Unlike the United States, there is no legislation for clinical research in the UK to mandate the inclusion of ethnic minorities and they are underrepresented in European trials compared with those conducted in the United States. This restricts generalization of research findings. This systematic review of the barriers to the recruitment of ethnic minority participants into psychiatric research is based on a comprehensive literature search. Nine included papers explore such barriers based on the authors’ and participants’ experiences of research. These barriers are mainly categorized as: participant related, practical issues, family/community related, health service related and research process issues. This review provides a compilation of important barriers to recruitment which can facilitate future research. The barriers that were identified are not all unique to participants from ethnic minorities, although the way in which they manifest themselves is often distinct in minority groups. It is important that these barriers are considered when designing research design so that solutions to overcome such obstacles can be incorporated in research protocols from the start and appropriate resources allocated. Copyright © 2014 John Wiley & Sons, Ltd.     

Systemic Effects of Intracoronary Nitroglycerin during Coronary Angiography in Children after Heart Transplantation

Coronary spasm during coronary angiography for vasculopathy in children can be prevented by the intracoronary administration of nitroglycerin. We reviewed the anesthesia and catheterization reports and charts for pediatric transplant recipients who underwent angiography from 2005 through 2010. Correlation analysis was used to study the relation of post-injection systolic blood pressure (SBP) to nitroglycerin dose. Forty-one angiographic evaluations were performed on 25 patients (13 male and 12 female). Mean age was 9.9 ± 3.2 years (range, 3.3–16.1 yr). The mean total dose of nitroglycerin was 2.93 ± 1.60 µg/kg (range, 1–8 µg/kg).There was a significant drop between the baseline SBP (mean, 106 ± 21.6 mmHg) and the lowest mean SBP before nitroglycerin administration (78 ± 13.2, P <0.0001, paired t test). There was no significant additional change in SBP (mean after nitroglycerin administration, 80.7 ± 13.1 mmHg; P = 0.2). There was a significant drop in lowest heart rate between baseline (109 ± 16.5 beats/min) and before nitroglycerin administration (89 ± 14.3 beats/min; P <0.0001, paired t test). There was no significant additional change in heart rate (mean heart rate after nitroglycerin, 84 ± 17.7 beats/min; P = 0.09). There were 2 interventions for SBP before nitroglycerin and 2 after nitroglycerin. One child experienced a transient ST-T–segment change during angiography after nitroglycerin. In the highest dose range, the additional decrease in SBP was 7.2 mmHg (P=0.03). Routine intracoronary nitroglycerin administration in this dose range produced no significant changes in SBP or heart rate in children.Key words: Child, coronary angiography, coronary vasospasm/etiology, dose-response relationship, drug, heart transplantation/adverse effects, hemodynamics/drug effects, nitroglycerin/administration & dosage/therapeutic use, postoperative complications/therapy, retrospective studies, vasodilation/drug effectsAllograft coronary disease in children occurs with increasing frequency after transplantation, as a function of time. In a multicenter study,¹ the incidence of coronary artery disease in children 5 years post-transplant was 17% of all recipients. Coronary angiography remains the gold standard in the detection of vasculopathy in heart-transplant recipients.² Coronary artery spasm can complicate selective coronary angiography and result in myocardial ischemia. Coronary spasm can simulate the angiographic appearance of graft vasculopathy and cause diagnostic confusion.³ The spasm can arise from manipulation of the arterial wall by the catheter or from intraluminal injection of contrast material. In cardiac transplant recipients, coronary artery spasm has been reported in as many as 4.9% of coronary angiograms.³In adults, intracoronary nitroglycerin is routinely administered during coronary angiography to prevent coronary artery spasm.⁴ In children, however, safety and dosage guidelines for intracoronary nitroglycerin have not yet been firmly established. A dose of 3 µg/kg can be extrapolated by weight from the established adult dose of 200 µg; this dose was used in a study of children after the arterial switch operation and was shown to produce coronary vasodilation—with a small reduction in systolic blood pressure (SBP) and no noteworthy change in heart rate—in a control group of patients.^5,6We previously reported a case of coronary artery spasm during routine coronary angiographic monitoring in a 9-year-old boy who had undergone heart transplantation as an infant.⁷ After left main coronary artery injection of contrast material, the patient''s left anterior descending and left circumflex coronary arteries appeared to be diffusely narrow, and he developed marked ST-segment elevation, hypotension, and ventricular tachycardia. After cardiopulmonary resuscitation, he recovered uneventfully and displayed normal systolic function. Coronary angiography one month later, with the administration of intracoronary nitroglycerin before the injection of contrast material, revealed normal coronary artery diameter and was accomplished without complication.Since 2005, intracoronary nitroglycerin has routinely been used in pediatric transplant patients during biennial selective coronary angiographic monitoring at our institution. The purpose of the study is to report our experience with the routine use of intracoronary nitroglycerin for coronary angiography in children: its effects on blood pressure, on heart rate, and on the occurrence of arrhythmia and ST-segment elevation.