It is the object of the present invention to provide a dental drill which while having a simple structure and being easy to handle can be produced at low costs and permits a rapid drilling of fillings with little strain on the patient.

According to the invention this object is achieved through the features of the main claim. The subclaims show advantageous developments of the invention.

Hence, according to the invention a dental drill is provided with a shaft and a cutting portion equipped with cutting edges. At the front side the dental drill comprises two main cutting edges and a transitional cutting edge. Several additional cutting edges are arranged laterally on the cutting portion or head. The main cutting edges of the dental drill converge in a central axis of the dental drill and directly pass into two lateral cutting edges. In an advantageous embodiment the main cutting edges form a tip or a transitional cutting edge which is semicircular when viewed laterally.

The dental drill of the invention is characterized by a number of considerable advantages. Due to the fact that the two main cutting edges are arranged at the front area of the cutting portion, the drilling performance of the dental drill in the axial direction is excellent. Since the two main cutting edges are advantageously configured such that they converge and meet at the central axis of the dental drill, the drill cuts across the whole area of the main cutting edge. This means that the inventive drill need not comprise any transverse cutting edge. As a consequence, the disadvantageous effect of the transverse cutting edge, which normally interconnects the, two main cutting edges and only squeezes the material to be drilled in the area of the transverse cutting edge can be avoided. As a result, the dental drill exhibits excellent cutting effects and fillings can be drilled out very rapidly. Since at least two additional cutting edges into which the two main cutting edges directly extend are provided laterally on the cutting portion, a dentist can also remove filling material by preparatory techniques exploiting lateral contact. Hence, the dentist in sectioning the filling can produce relatively large pieces of material, which can then be sucked off from the patient's mouth in an easy and reliable manner e.g. by means of a suction device or can be removed from the mouth by rinsing the same. The risk that drilled filling material will be swallowed by the patient can thus be considerably reduced.

The lateral cutting edges are advantageously arranged along helical lines. As a result, the lateral cutting portion can be produced relatively easily and an adequate transverse cutting force is imparted to the drill to remove material in a time saving manner by way of a preparatory technique exploiting lateral contact. Such an arrangement also helps to suppress vibrations and the occurrence of drilling noise.