Gender Differences and Predictors of Practice Ownership in a Sample of Ontario Dentists.

PURPOSE: To examine the influence of gender on practice ownership among Ontario dentists. METHODS: In 2012, a 52-item survey was sent to a random sample of 3000 Ontario dentists (1500 men and 1500 women) to collect information on personal, professional and sociodemographic characteristics. The resulting data were analyzed using descriptive statistics and linear regression modeling. RESULTS: The 867 respondents included 463 men, 401 women and 3 people whose gender was unreported, yielding a response rate of 29%. Univariate regression analyses revealed that male dentists were 2.2 times more likely to be practice owners than female dentists. Dentists > 60 years were less likely to be owners than younger dentists. The odds of practice ownership were lower for dentists who preferred the ability to secure part-time work. A higher level of confidence in one's business acumen significantly predicted practice ownership. Dentists making concessions in their career to pursue family life were more likely to be associates, and those who perceived that their partners made concessions to aid in their career were more likely to be owners. In multivariate analyses, the effect of gender on practice ownership became insignificant, yet the influence of age, preference for career aspects, confidence in business skills and perceptions regarding concessions by self and partner persisted. Gender-stratified analyses revealed that familial factors significantly predicted ownership for female dentists, but not for male dentists. CONCLUSION: Gender appears to be linked to practice ownership, but when other factors are considered such as age, preference for part-time work, higher levels of confidence in business skills and perceptions of career concessions, the relationship does not remain.

Gender Differences and Predictors of Work Hours in a Sample of Ontario Dentists.

PURPOSE: To determine the influence of gender on weekly work hours of Ontario dentists. METHODS: In 2012, a 52-item survey was sent to a random sample of 3000 Ontario dentists (1500 men and 1500 women) to collect information on personal, professional and sociodemographic characteristics. The resulting data were analyzed using descriptive statistics and linear regression modeling. RESULTS: The 867 respondents included 463 men, 401 women and 3 people whose gender was unreported, yielding a response rate of 29%.Most dentists worked full-time, with men working, on average, 2 h/week longer than women. Younger dentists worked more than older dentists. Practice ownership increased weekly work hours, and men reported ownership more often than women. Canadian-trained women worked significantly fewer hours than those trained internationally. Women were more likely than men to work part time and take parental leave and more often reported being primary caregivers and solely responsible for household chores. Women with partner support for such tasks worked more hours than those who were solely responsible. Dentists with children ≤ 3 years of age worked fewer hours than those without children; however, after controlling for spousal responsibility for caregiver duties, this effect was eliminated. More women than men reported making concessions in their career to devote time to family. CONCLUSION: Gender, age, practice ownership, training location and degree of spousal support for household and caregiving responsibilities were predictors of weekly work hours. For women specifically, training location and household and caregiving responsibilities predicted weekly work hours.

The feminization of dentistry: implications for the profession.

Over the last 40 years, the proportion of women in dentistry has been rising steadily, raising questions about the effects of this feminization on the profession. A review of the literature, although limited, highlights potentially important areas related to gender, including impact on work hours, practice models, professional incomes, the dentist-patient relationship, clinical philosophies, specialty practice, academia and leadership. Although cohorts of predominantly female dentists are only beginning to enter the workforce and, thus, it is difficult to predict the long-term effects, some trends are evident: women are less likely than men to own their practice; women may work 4-6 fewer hours a week and see fewer patients; there is a pay differential; female general practitioners and specialists appear more likely to work in urban centres; and women are less prominent in the specialties, academia and leadership roles. Thus, the profession may shift toward less entrepreneurship, more urbanization and, possibly, fewer clinical hours available to the population as a result of feminization. With the ultimate goal of excellence in patient care, this may entail increases in student enrolment, formal incentives for practice relocation to rural communities, more business education and policies to modify advanced education and training for women with children. This knowledge, although still not robust, is relevant for policy, educational institutions and professional governing bodies.

Extremely low frequency pulsed electromagnetic field designed for antinociception does not affect microvascular responsiveness to the vasodilator acetylcholine.

A 225 microT, extremely low frequency, pulsed electromagnetic field (PEMF) that was designed for the induction of antinociception, was tested for its effectiveness to influence blood flow within the skeletal microvasculature of a male Sprague-Dawley rat model (n = 103). Acetylcholine (0.1, 1.0, or 10 mM) was used to perturb normal blood flow and to delineate differential effects of the PEMF, based on degree of vessel dilation. After both 30 and 60 min of PEMF exposure, we report no effects on peak perfusion response to acetylcholine (with only 0.2% of the group difference attributed to exposure). Spectral analysis of blood flow data was generated to obtain information related to myogenic activity (0.15-0.40 Hz), respiratory rate (0.4-2.0 Hz), and heart rate (2.0-7.0 Hz), including the peak frequency within each of the three frequency regions identified above, peak power, full width at half maximum (FWHM), and mean within band. No significant effects due to exposure were observed on myogenic activity of examined blood vessels, or on heart rate parameters. Anesthesia-induced respiratory depression was, however, significantly reduced following PEMF exposure compared to shams (although exposure only accounted for 9.4% of the group difference). This set of data suggest that there are no significant acute physiological effects of 225 microT PEMF after 30 and 60 min of exposure on peak blood flow, heart rate, and myogenic activity, but perhaps a small attenuation effect on anesthetic-induced respiratory depression.

Light alters nociceptive effects of magnetic field shielding in mice: intensity and wavelength considerations.

Previous experiments with mice have shown that repeated 1 hour daily exposure to an ambient magnetic field-shielded environment induces analgesia (antinociception). The exposures were carried out in the dark (less than 2.0x1016 photonss-1m-2) during the mid-light phase of the diurnal cycle. However, if the mice were exposed in the presence of visible light (2.0x1018 photonss-1m-2, 400-750 nm), then the analgesic effects of shielding were eliminated. Here, we show that this effect of light is intensity and wavelength dependent. Introduction of red light (peak at 635 nm) had little or no effect, presumably because mice do not have photoreceptors sensitive to red light above 600 nm in their eyes. By contrast, introduction of ultraviolet light (peak at 405 nm) abolished the effect, presumably because mice do have ultraviolet A receptors. Blue light exposures (peak at 465 nm) of different intensities demonstrate that the effect has an intensity threshold of approximately 12% of the blue light in the housing facility, corresponding to 5x1016 photonss-1m-2 (integral). This intensity is similar to that associated with photoreceptor-based magnetoreception in birds and in mice stimulates photopic/cone vision. Could the detection mechanism that senses ambient magnetic fields in mice be similar to that in bird navigation?

A literature review: the effects of magnetic field exposure on blood flow and blood vessels in the microvasculature.

The effect of magnetic field (MF) exposure on microcirculation and microvasculature is not clear or widely explored. In the limited body of data that exists, there are contradictions as to the effects of MFs on blood perfusion and pressure. Approximately half of the cited studies indicate a vasodilatory effect of MFs; the remaining half indicate that MFs could trigger either vasodilation or vasoconstriction depending on initial vessel tone. Few studies indicate that MFs cause a decrease in perfusion or no effect. There is a further lack of investigation into the cellular effects of MFs on microcirculation and microvasculature. The role of nitric oxide (NO) in mediating microcirculatory MF effects has been minimally explored and results are mixed, with four studies supporting an increase in NO activity, one supporting a biphasic effect, and five indicating no effect. MF effects on angiogenesis are also reported: seven studies supporting an increase and two a decrease. Possible reasons for these contradictions are explored. This review also considers the effects of magnetic resonance imaging (MRI) and anesthetics on microcirculation. Recommendations for future work include studies aimed at the cellular/mechanistic level, studies involving perfusion measurements both during and post-exposure, studies testing the effect of MFs on anesthetics, and investigation into the microcirculatory effects of MRI.

Exposure to a specific pulsed low-frequency magnetic field: a double-blind placebo-controlled study of effects on pain ratings in rheumatoid arthritis and fibromyalgia patients.

BACKGROUND: Specific pulsed electromagnetic fields (PEMFs) have been shown to induce analgesia (antinociception) in snails, rodents and healthy human volunteers. OBJECTIVE: The effect of specific PEMF exposure on pain and anxiety ratings was investigated in two patient populations. DESIGN: A double-blind, randomized, placebo-controlled parallel design was used. METHOD: The present study investigated the effects of an acute 30 min magnetic field exposure (less than or equal to 400 microTpk; less than 3 kHz) on pain (McGill Pain Questionnaire [MPQ], visual analogue scale [VAS]) and anxiety (VAS) ratings in female rheumatoid arthritis (RA) (n=13; mean age 52 years) and fibromyalgia (FM) patients (n=18; mean age 51 years) who received either the PEMF or sham exposure treatment. RESULTS: A repeated measures analysis revealed a significant pre-post-testing by condition interaction for the MPQ Pain Rating Index total for the RA patients, F(1,11)=5.09, P<0.05, estimate of effect size = 0.32, power = 0.54. A significant pre-post-effect for the same variable was present for the FM patients, F(1,15)=16.2, P<0.01, estimate of effect size = 0.52, power =0.96. Similar findings were found for MPQ subcomponents and the VAS (pain). There was no significant reduction in VAS anxiety ratings pre- to post-exposure for either the RA or FM patients. CONCLUSION: These findings provide some initial support for the use of PEMF exposure in reducing pain in chronic pain populations and warrants continued investigation into the use of PEMF exposure for short-term pain relief.