John Whitworth

Bio: John Whitworth is an academic researcher from Newcastle University. The author has contributed to research in topics: Articaine & Pulp (tooth). The author has an hindex of 23, co-authored 67 publications receiving 2168 citations. Previous affiliations of John Whitworth include University of Newcastle.

Methods of filling root canals: principles and practices

Abstract: Contemporary research points to infection control as the key determinant of endodontic success. While epidemiological surveys indicate that success is most likely in teeth which have been densely root-filled to within 2 mm of root-end, it is unclear whether the root canal filling itself is a key determinant of outcome. It is also unclear how different materials and methods employed in achieving a ‘satisfactory’ root filling may impact on outcome. This article provides an overview of current principles and practices in root canal filling and strives to untangle the limited and often contradictory research of relevance to clinical practice and performance.

Undergraduate Curriculum Guidelines for Endodontology

Abstract: Earlier editions of the ESE undergraduate curriculum guidelines for Endodontology were published in 1992 and 2001 (International Endodontic Journal 25, 169–72; 34, 574–80) and formed a benchmarking reference for dental schools and regulatory bodies. Despite much technological advance and the publication of quality guidelines for endodontic treatment (European Society of Endodontology 2006), studies published during the last decade have continued to show disappointing technical standards of root canal treatment in European populations (Eriksen et al. 2002, Segura-Egea et al. 2004, Tavares et al. 2009, Gencoglu et al. 2010, Peters et al. 2011). Longitudinal observational studies have also reinforced the relationship between treatment quality and persistent disease (Eckerbom et al. 2007, Kirkevang et al. 2007). Although a limited number of European countries have recognized endodontics as a speciality, there is no doubt that the vast proportion of endodontic procedures will continue to be undertaken by general dental practitioners. Evidence suggests that many general practitioners lack sufficient knowledge of the factors important in determining the outcome of root canal treatment (Bjørndal et al. 2007) and that basic principles are often disregarded (Peciuliene et al. 2009). Some of this may reflect the acquisition of foundational knowledge and skills during undergraduate training, where standards remain highly variable (Eleftheriadis & Lambrianidis 2005, Er et al. 2006, Sonntag et al. 2008, Burke et al. 2009, Kelbauskas et al. 2009, Khabbaz et al. 2010). It is therefore important to ensure that undergraduate training is undertaken to a level that encourages deep understanding of the factors important in determining clinical outcome. It is beyond the scope of this pre-amble to provide a detailed critique of all aspects of endodontic practice, but the example of root canal treatment serves to illustrate the motivation of the European Society of Endodontology in promoting standards of scientific education and clinical training across a broad undergraduate curriculum in Endodontology. This includes but is not limited to diagnostic and treatment procedures for the prevention and management of pulpal and periradicular disease, and for the preservation, restoration and monitoring of pulpally compromised teeth that would otherwise be lost. It is implicit that the procedures defined should be exercised within a model of holistic, evidence-based patient care and should be undertaken to support the oral and general health of patients. This document represents a guideline for an undergraduate curriculum and cannot be exhaustive. The underlying principle must be that a minimum level of competence is reached prior to graduation and that an ethos of continuing professional development is instilled in the graduate.

Preclinical endodontology: an international comparison.

Abstract: Aim The aim of this study was to compare preclinical endodontic teaching in Europe, Scandinavia and North America, and to place recent UK data in an international context Methodology A postal questionnaire was sent to all undergraduate dental schools in North America, Scandinavia, and Europe Data were requested on a range of issues relating to endodontic teaching Results Forty-three percent of the 170 schools surveyed returned completed questionnaires There was considerable international consensus on the content of preclinical courses, with most schools advocating preflaring canal preparation techniques, sodium hypochlorite for irrigation, and cold lateral condensation as the standard obturation method There was little consensus on the standard use of intracanal medicaments, though calcium hydroxide was universally popular The practice of single visittreatment was advocated by at least 70% of schools in all geographical areas A number of innovations appear to be gaining acceptance in preclinical teaching, with more than 20% of schools teaching the use of electronic apex locators, and a quarter of Western European, Scandinavian and North American schools embracing nickel-titanium instrumentation Regional differences in the priority and resource given to endodontic teaching were striking On average, UK schools had the worst staff:student ratios for preclinical endodontic teaching, and allocated substantially less time allocation for this teaching compared with Western European, Scandinavian and North American schools Conclusions It was concluded that although teachers in the UK were broadly advocating techniques recommended elsewhere, the academic infrastructure and priority given for endodontic teaching in the UK was limited in the international context This may have some impact on the quality of endodontic provision within the UK General Dental Services

Properties and applications of calcium hydroxide in endodontics and dental traumatology.

Abstract: Calcium hydroxide has been included within several materials and antimicrobial formulations that are used in a number of treatment modalities in endodontics. These include, inter-appointment intracanal medicaments, pulp-capping agents and root canal sealers. Calcium hydroxide formulations are also used during treatment of root perforations, root fractures and root resorption and have a role in dental traumatology, for example, following tooth avulsion and luxation injuries. The purpose of this paper is to review the properties and clinical applications of calcium hydroxide in endodontics and dental traumatology including its antibacterial activity, antifungal activity, effect on bacterial biofilms, the synergism between calcium hydroxide and other agents, its effects on the properties of dentine, the diffusion of hydroxyl ions through dentine and its toxicity. Pure calcium hydroxide paste has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. Its main actions are achieved through the ionic dissociation of Ca2+ and OH- ions and their effect on vital tissues, the induction of hard-tissue deposition and the antibacterial properties. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. It has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also an effective anti-endotoxin agent. However, its effect on microbial biofilms is controversial.

Managing Carious Lesions: Consensus Recommendations on Carious Tissue Removal.

Abstract: The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental caries and control activity of existing cavitated lesions to preserve hard tissues and retain teeth long-term. Entering the restorative cycle should be avoided as far as possible. Controlling the disease in cavitated carious lesions should be attempted using methods which are aimed at biofilm removal or control first. Only when cavitated carious lesions either are noncleansable or can no longer be sealed are restorative interventions indicated. When a restoration is indicated, the priorities are as follows: preserving healthy and remineralizable tissue, achieving a restorative seal, maintaining pulpal health, and maximizing restoration success. Carious tissue is removed purely to create conditions for long-lasting restorations. Bacterially contaminated or demineralized tissues close to the pulp do not need to be removed. In deeper lesions in teeth with sensible (vital) pulps, preserving pulpal health should be prioritized, while in shallow or moderately deep lesions, restoration longevity becomes more important. For teeth with shallow or moderately deep cavitated lesions, carious tissue removal is performed according toselective removal to firm dentine.In deep cavitated lesions in primary or permanent teeth,selective removal to soft dentineshould be performed, although in permanent teeth,stepwise removalis an option. The evidence and, therefore, these recommendations support less invasive carious lesion management, delaying entry to, and slowing down, the restorative cycle by preserving tooth tissue and retaining teeth long-term.

GaInSn usage in the research laboratory

Abstract: GaInSn, a eutectic alloy, has been successfully used in the Magneto-Thermofluid Research Laboratory at the University of California-Los Angeles and at the Princeton Plasma Physics Laboratory for the past six years. This paper describes the handling and safety of GaInSn based on the experience gained in these institutions, augmented by observations from other researchers in the liquid metal experimental community. GaInSn is an alloy with benign properties and shows considerable potential in liquid metal experimental research and cooling applications.