No fear of the drill

Diamond coated drills reduce the use of anesthetics in 70% of the cases

MIGUEL BOYAYANBefore reaching the market, the drills were tested by 500 dentistsMIGUEL BOYAYAN

At last, painless dental treatment. This, at least, is what is promised by researchers from a company from São José dos Campos called Clorovale Diamantes, who are launching in the market, this August, a new line of dental drills with the tip coated with synthetic diamond. The biggest novelty is that the drill works by vibration, using ultrasound waves. It hardly makes any noise at all, unlike conventional drills, which work by rotation and make a little noise that scares a lot of people. The best news is that it reduces pain, and in the majority of cases does away with the use of anesthetics.

The result of six months’ research, the new drill is being regarded by dentists as a revolution in dentistry. “Treatment with diamond-tipped drills with ultrasound equipment is minimally invasive and far more precise. That is why it does not cause any unnecessary wear and trauma to the teeth”, explains physicist Vladimir Jesus Trava Airoldi, one of Clorovale’s partners and one of the pioneers in the study of artificial diamonds in Brazil, in his capacity as a researcher of the National Institute for Space Research (Inpe). “The ultrasound devicemakes these bits vibrate, affecting only the cavities and preserving the healthy part of the tooth”, he says. The drill, the researcher explains, is adaptable to the ultrasound apparatuses that dental surgeries have, used for periodontal treatment (treating problems in the region of the tooth next to the gum).

It works by vibrating at a frequency of 30 kilohertz (30,000 oscillations a second), with movements like those of a stone-breaking machine, although far smoother. Dentists who have already tested the product have come to the conclusion that in over 70% of the cases, treatment is painless. This is because the drill reaches the dental cavity by vibration, without crushing the dentine, the region where the nerve filaments that make the tooth sensitive are located.

The company is also placing in the market a conventionally rotating drill with a diamond-CVD tip, a material obtained by means of the process called Chemical Vapor Deposition. It is the same diamond used for coating the drills of ultrasound apparatuses. “We use the same technique to cover the two drills. The only thing that changes is the way that the tip acts in relation to the tooth, by rotation or by vibration”, Airoldi explains. Clorovale was a pioneer in Latin America in developing CVD diamonds, and is the only company in the world to master the technology for producing dental drill tips with this material.

Clorovale’s drills offer many advantages over the traditional ones, which are coated with HPHT (High Pressure, High Temperature) artificial diamonds. This technology uses diamond powder and nickel solder, on a steel shaft. CVD-diamond, though, grows on the shaft itself, coating it to the desired thickness. “Drills with CVD-diamond sustain minimal wear with use, and they have a longer useful life than the traditional drills”, explains Airoldi. Furthermore, no metals or other residues harmful to the environment or to the patient are used in their manufacture, because the raw materials – mainly hydrogen – are biocompatible (see Pesquisa FAPESP  nº 52).

No traumas
Before going into the market, the drills were tested by some 500 dentists. The results were encouraging. “The drills for the ultrasound devices are the best and the cheapest innovation in the last few years, as far as dental treatment is concerned”, says Professor Luis Augusto Conrado, from the School of Odontology of the Paraíba Valley University. “They will make life easier for dentists, and alleviate traumas for the patients.” Annual sales of dentists’ drill come to over R$ 1.1 billion world-wide. In Brazil alone, this is a market that has a turnover of R$ 70 million a year.

The company estimates that about 40,000 dentists (25% of the total) will be using the new drills in three years. The international market will also be explored, since there are no similar drills abroad. Sales to other countries are excepted to begin in six months. The target is to reach 15% of the 300,000 professionals working in odontology in Latin America, and 3% of the 2.5 million dentists from the rest of the world, which means almost 100,000 people.

Clorovale’s drill tips cost between R$ 30 (for rotation) and R$ 80 (ultrasound) and are far more expensive than the conventional diamond ones (R$ 3.00). But, according to Clorovale’s partners, the cost-benefit ratio is worth it, since they are at least 30 times more long-lasting. The new tips will be sold in cases with four units, containing one conical tip, one conical stem, a cylindrical one and a spherical one. These are the four models most used by dentists.

The two drills have already been patented in Brazil, the United States, Canada, Japan and Europe. Royalties will be divided between Clorovale, the Inpe and FAPESP, which took part in the project for the drill for ultrasound apparatuses by means of finance from the Small Business Innovation Research Program (PIPE). In this case, each of the partners keeps 1/3 of the royalties, which amount to 4% of the company’s net sales. With the conventional rotating drills, Inpe has the right to 2/3 of the royalties and Clorovale to the rest. The CVD-diamond can be obtained in any size and shape, with a degree of purity far higher than the first artificial diamonds. It has the same characteristics as natural diamond, the hardest material found in nature. Other advantages of the CVD-diamond are its low coefficient of attrition, its high conductivity of heat, its resistance to cosmic, nuclear and ultraviolet radiation, and its excellent integration with bone. This gives it a vast field of applications.

In the space area, it can be used in heat dissipaters and in the protection of solar cells and surfaces subject to being bombarded by cosmic particles. In microelectronics, it is used in making faster devices with a more efficient thermal profile. In the optical market, its use is associated with components for high power lasers. For the time being, Clorovale has been doing research with a view to the use of CVD-diamond in machine tools and diamond tubes for cutting machinery. They are also studying the manufacture of CVD-diamond electrodes for the electrochemical area and for fuel cells (to generate electricity).
Ample advantage
The manufacturing of synthetic diamonds by Clorovale was only possible thanks to the close relationship between the company and a few research centers. Three of Clorovale’s directors, physicians Vladimir Airoldi, Evaldo Corat and Édson del Bosco, also work at the Inpe. The company has four more partners: Professor João Roberto Moro, from São Francisco University (USF), in Itatiba (SP); chemical engineer Kiyoe Umeda, of the National Nuclear Energy Commission (CNEN); chemist Luiz Gilberto Barreta, of the Technological Center of the Air Force (CTA); and Marcos Gama Lobo, who is a technician in electromechanics. Together, they have shown that it is possible to transform knowledge generated in centers for high technology into products with good applicability in the market.

The Project
Development of Devices in CVD-Diamond for Short Term Applications (nº 98/15038-1); Modality Small Business Innovation Research Program (PIPE); Coordinator Kiyoe Umeda – Clorovale; Investment R$ 135,333.50 and US$ 76,485.00