Sir, I congratulate the authors on their excellent review of the supply of dental workers in the Shropshire and Staffordshire counties (P. Hornby et al. BDJ 2006; 200: 575–579). However, the article barely touches on the demand side of the supply and demand aspects of a true workforce review.

In the Department of Health's Review of the workforce, published in July 2004,1 this aspect received more or less equal weight. The review concluded that 'adult dental attendance will increase by 40% between 1998 and 2018'. Additionally, the review suggested that 'projections of adult treatment hours demanded imply a small overall growth in demand to 2011 (+5%) and a small decrease in the next 10 years (−3%). On a higher estimate, projections imply a larger growth between 2001-2011 (+7%) and very little growth from 2011-2021 (+0.1%)'.

Whilst I appreciate that this review was published late in this study, it is still referred to in this paper. The authors do not appear to have built these projections into their results.

Indeed, demand is referred to by the authors in only two paragraphs towards the end of their paper. They have based their estimates of needed workforce on an assumption that dentists see four NHS patients an hour – 126 patients a week – figures which were supported by the participants at workshops. However, figures produced by the Office of Manpower Economics, published as part of the 2000-1 Doctors and Dentists' Review Body Report2 show that dentists working in the GDS were actually seeing 165 patients a week then. I know of no evidence published since then which indicates a lower figure – although an aim of the changes to the GDS contract introduced on 1 April 2006 is to effect a 5% reduction in workload. The same OME report did suggest that fully private dentists see less than 100 patients a week so, of course, the (anecdotally) reported shift by GDPs into the private sector may bring the average figures more into line with the authors' suggestion.

Finally, I do not understand the authors' assumptions about the use of hygienists and therapists and their contribution to the supply of dental workforce. Table 5 – which was a list of DPB supplied GDS treatment types — was extrapolated into figures for visits to dentists, hygienists and therapists, although the basis for these calculations was not shown. This led them to an assumption that only 54% of future visits need to be dentists.

I have no idea whether this figure is correct. We do not know if the authors took into account that all dental care must be preceded by an examination and diagnosis by a dentist. Also, we not are advised whether the authors allowed for the reduced output produced by dental care professionals, measured in WTEs, as suggested in the Department of Health Workforce Review.

I would welcome the authors' explanations.

Dr Peter Hornby responds on behalf of his co-authors: I should start by emphasising that we were commissioned specifically to look at the situation in Shropshire and Staffordshire. While we necessarily referenced other dental studies, including national reports, the basis of our report and the subsequent paper to the British Dental Journal was drawn primarily from data and observations within these two counties. The demand side of our study, while given less emphasis in the paper because of restrictions in the length of the paper, was given equal emphasis in the actual study.

We explored the demand side with the help of independent dental experts drawn from the local strategic health authority and using data on current and previous types of case mix volume. From this and available demographic information we projected growth in demand reflecting expert views about change in case mix with less restorative work occurring over time.

Our projection of 126 patients per week is indeed a lower rate than in the dentist review body report but was an attempt to reflect local dentist opinion collected through workshops and focus group meetings on what constitutes a reasonable workload level going into the future.

Detailed calculations were made about the potential contribution dental hygienists and therapists could make in dental services with appropriate training operating under the new regulations. They are based on judgements made by our dental expert colleagues through an analysis of projected case mix and workload and involved their judgements of which of the seven basic dental procedures could be allocated to each type of dental professional on the basis of competence to practise.

Our supply side assessment using Likert scales to provide a qualitative view of leaving intentions and related causal factors led us to identify emerging issues around gender and age which could impact significantly on the future availability of dental professionals in whole time equivalent terms. The brief for the study did not allow us to pursue its implications in depth through the development of alternate scenarios.

Our intention in all this was not to define in absolute terms through a single scenario the exact number of dental professionals required in these two counties in the future, but rather to show that there were routes through to overcoming dentist shortage in these two counties through changes in the approach taken to the provision of dental care and the training of dental professionals.