JAMES HULL was in his element two weekends ago, mixing his twin passions — business and charity — at a sponsored cricket match.

Hull, who has become Britain’s richest dentist after building up a chain of 34 outlets, was hosting an annual match between his own team and the Lord’s Taverners.

His celebrity guests included Chris Tarrant, Sir Tim Rice, Rory Bremner and Charlotte Church. Hull financed the charity match out of his own pocket, but such is his enthusiasm to promote his business, that it is sometimes hard to distinguish between his personal and professional life. But one thing is clear: he wants to build James Hull Associates (JHA) into Britain’s most successful dental chain.

This autumn he intends (subject to market conditions) to float the group on the stock market and raise £12.5m. He says Bell Lawrie White has already put a discounted cashflow valuation on the company of £60m of which he controls 46%. The second-biggest investor is 3i, followed by the integrated- finance division of HBOS.

Industry analysts say if he does float at this level, his business model will come under close examination. Research by The Sunday Times has raised issues about pricing discrepancies in his operation as well.

When our reporter booked an initial consultation with each of James Hull’s 34 nationwide practices he was offered a diverse range of quotes, from £85 at The Eastman Private Practice in London, to £65 in the Soho practice, and down to £15 at the Petwyn surgery in Wales.

In his defence Hull says: “JHA has different price lists for its practices inside London and those outside, owing to the very different costs of running those practices. There are also different charges for work, depending on the seniority of the dentist giving the treatments.”

However, this does not explain why the Towcester general practice in Northamptonshire gave the highest quote, at £89, for an initial consultation. And our reporter was not told about the qualifications of each dentist he contacted.

To take the research further, we then arranged a consultation in six of JD Hull’s nationwide practices, and discovered that price discrepancies ran deeper still. Our reporter did not get the same estimate once, and while a certain variation of professional opinion is expected, prices differed by nearly £500.

Our interest was prompted by a recent investigation into dentistry by The Office of Fair Trading. One of the key recommendations from the study was that the £1 billion-a-year private dental market should do “more to inform and explain to consumers their options for treatment and their costs”. It said: “Consumers do not generally have basic information — eg about prices — to make properly informed choices.”

Hull does concede that our “inquiries have raised some issues regarding our charges and we intend to consider them in due course . . . we have already reminded all our 400 staff about company charging policy and our commitment to total transparency at all times”.

But he claims that during our research our investigator “may not have been consistent in his instructions to the dentist”.

The reporter who he let the dentist make all the recommendations for treatment. At the James Hull Dental Care centre in Surrey the estimate for recommended work came to £113, in Cardiff it was £225, in London’s Kensington it was £685 and at the Eastman Private Practice, also in London, the recommended cost was £272. When the different charges were put to the company, all the dentists gave an explanation of their recommended treatments.

Hull says: “The quotations are for a variety of treatments and part-treatments . . . In some cases they cover only the part treatment of an amalgam filling. In others the complete treatment, including the filling and a porcelain inlay, are included. At least one quotation also included remedial work on his chipped front tooth, for which the dentist says he was asked to quote.”

Hull, who set up his first practice in 1988, differentiates his business from his rivals, Oasis and IDH. He says he is not a “drill and fill” operator.

His specialist dentists, who are self-employed, can earn more than £100,000 a year from undertaking highly complex work.

It is also highly profitable work, with gross margins of 45%. Some 8% of his 250,000 clients spend between £30,000 and £35,000 a year on dental work.

The performance of Britain’s two quoted dental chains show that the City is giving a lukewarm hearing to the sector. Oasis is valued at only a third of revenues of £70m, and IDH, which has issued three profit warnings since its flotation, is trading at just 13% of forecast revenues of £72m.

Hull is plannning to float JHA at three times annualised revenues.

He says he develops his own outlets, investing between £750,000 and £1m at each site, and at his mature outlets he says he is now achieving 32% Ebitda (earnings before interest, tax, depreciation and amortisation). This is impressive, but if Hull is going to float his company, analysts say he will have to explain why he deserves such a premium valuation.

On the firm’s internet site it promises to “take the mystique out of dentistry”. Some fund managers may want Hull to take the mystique out of valuation as well. For a company that made a loss of £2.8m for the year to 2001, a valuation of £60m demands a leap in imagination.

Additional reporting: Emma Friedman