Problem-based learning in dental education: what's the evidence for and against... and is it worth the effort?

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.All Australian dental schools have introduced problem-based learning (PBL) approaches to their programmes over the past decade, although the nature of the innovations has varied from school to school. Before one can ask whether PBL is better than the conventional style of education, one needs to consider three key issues. Firstly, we need to agree on what is meant by the term PBL; secondly, we need to decide what “better” means when comparing educational approaches; and thirdly, we must look carefully at how PBL is implemented in given situations. It is argued that PBL fulfils, at least in theory, some important principles relating to the development of new knowledge. It also represents a change in focus from teachers and teaching in conventional programmes to learners and learning. Generally, students enjoy PBL programmes more than conventional programmes and feel they are more nurturing. There is also some evidence of an improvement in clinical and diagnostic reasoning ability associated with PBL curricula. The main negative points raised about PBL are the costs involved and mixed reports of insufficient grounding of students in the basic sciences. Financial restraints will probably preclude the introduction of pure or fully integrated PBL programmes in Australian dental schools. However, our research and experience, as well as other published literature, indicate that well-planned hybrid PBL programmes, with matching methods of assessment, can foster development of the types of knowledge, skills and attributes that oral health professionals will need in the future.T Winning and G Townsen

Lower limb coordination and stiffness during landing from volleyball block jumps

Original article can be found at: http://www.informaworld.com/ Copyright Informa / Taylor and Francis Group. DOI: 10.1080/15438620802103999The aim of the study was to investigate lower limb coordination and stiffness in five male and five female university volleyball players performing block jump landings. Coordination was assessed using angle – angle plots of the hip – knee, knee – ankle and hip – ankle joint couplings and discrete relative phase (DRP) of right – left joint couplings (i.e. left knee coupled with right knee). Leg stiffness was calculated as the ratio of the change in vertical ground reaction force (GRF) to the change in vertical displacement of the centre of gravity between ground contact and maximum vertical GRF. Knee stiffness was calculated as the ratio of the change in knee joint moment to the change in knee flexion angular displacement between ground contact and maximum knee joint moment. Comparison of the DRP angles between left and right legs indicated reduced symmetry between the left and right legs in females compared to males which may indicate greater likelihood of ligament strain in females compared to males. Furthermore, females exhibited reduced stability in the coordination between the left and right knee joints than males. Males exhibited significantly greater absolute and normalised leg stiffness and significantly greater absolute and normalised knee joint stiffness during landing compared to females. In conjunction with the coordination data, this may indicate reduced dynamic stability of the leg in females compared to males which may contribute to the greater incidence of ACL injury in females compared to males.Peer reviewe

Estrogen-induced effects on the neuro-mechanics of hopping in humans

Estrogen receptors in skeletal muscle suggest a tissue-based mechanism for influencing neuromuscular control. This has important physiological implications for both eumenorrheic women with fluctuating estrogen levels and those with constant and attenuated estrogen levels, i.e., women using the monophasic oral contraceptive pill (MOCP). This study examined the effects of endogenous plasma estrogen levels on leg stiffness (K(LEG)) and foot center of pressure (COP) during hopping. Nineteen females (Age = 28.0 +/- 4.2 years, Ht = 1.67 +/- 0.07 m, Mass = 61.6 +/- 6.8 kg) who had been using the MOCP for at least 12 months together with 19 matched, female, non-MOCP users (Age = 31.9 +/- 7.3 years, Ht = 1.63 +/- 0.05 m, Mass = 62.5 +/- 5.9 kg) participated. Non-MOCP users were tested at the time of lowest (menstruation) and highest (approximate to ovulation) estrogen whilst MOCP users were tested at Day 1 and Day 14 of their cycle. At each test session, K(LEG) (N m(-1) kg(-1)) and foot COP path length (mm) and path velocity (mm s(-1)) were determined from ground reaction force data as participants hopped at 2.2 Hz on a force plate. Statistical analysis revealed no significant (p < 0.05) differences for K(LEG). In contrast, significantly higher COP path length (30%) and COP path velocity (25%) were identified at approximate to ovulation compared to menstruation in the non-MOCP users. Whilst there was no evidence of an estrogen-induced effect on K(LEG); significantly elevated estrogen at approximate to ovulation presumably increased extensibility of connective tissue and/or diminished neuromuscular control. Consistent lower limb dynamics of MOCP users demands less reliance on acutely modified neuromuscular control strategies during dynamic tasks and may explain the lower rate of lower limb musculoskeletal injuries in this population compared to non-MOCP users

Antibacterial and immunomodulatory properties of azithromycin treatment implications for periodontitis

Macrolide antibiotics have been found to possess not only antimicrobial properties, but also modulate inflammation. In this review the multi-faceted properties of azithromycin are discussed. Due to the unique anti-inflammatory and antimicrobial properties, macrolides, and especially azithromycin, are currently used for a number of conditions which have both an inflammatory and microbial component. For the same reason, azithromycin may be of value as an adjunct in the management of periodontitis which, although driven by an infectious component, is largely a result of uncontrolled chronic inflammation.P. M. Bartold, A. H. du Bois, S. Gannon, D. R. Haynes, R. S. Hirsc