Drill template arrangement

A drilling assembly is provided for drilling a hole into a zygoma of a patient. The assembly can comprise a template, an extension unit, a drill guide unit, and first and second drills. The template can be configured for orientation within a patient's mouth and can comprise a guide sleeve having a longitudinal axis extending towards the zygoma when fitted on the patient. The extension unit can include a central bore and be slideably received within the guide sleeve. The drill guide unit can also include a central bore of a different diameter than that of the extension unit. The first drill can be slideably received within the central bore of the guide sleeve. The second drill can have an outer diameter different than that of the first drill and can be configured to be slideably received with the central bore of the drill guide unit.

PRIORITY INFORMATION

This application is a U.S. National Phase of International Application No. PCT/SE2006/000541, filed May 5, 2006, which claims priority to Swedish Patent Application No. SE 0501285-1, filed Jun. 3, 2005, each of which is hereby incorporated by reference in its entirety.

BACKGROUND

1. Field of the Invention

The present invention relates to an arrangement used on a drill template oriented in the mouth for forming holes intended to extend from the template and into the zygoma. The template in this case can comprise one or more guide sleeves which define the direction toward the zygoma.

2. Description of the Related Art

Various guide arrangements for guiding drills are already known in dentistry. Special care must be taken when forming holes for implants and screws which are to extend into and be anchored in the zygoma.

SUMMARY OF THE INVENTION

According to at least one of the embodiments herein is the realization that special problems may arise on account of the precision requirements that have to be met in terms of the hole direction when forming holes for implants and screws which are to extend into and be anchored in the zygoma. Incorrect handling and incorrect equipment can mean deviations from the drill direction defined with precision in the computer-aided equipment, which means there may be a high risk of the drill direction being wrong and of the drill penetrating through sensitive parts of the eye or orbital cavity.

The structure and orientation of the drill template is dealt with in a parallel application which was submitted on the same day as the present application and by the same applicant. The drill template is produced, inter alia, by means of computer-aided equipment in a manner known per se.

Embodiments of the present inventions aim to solve these problems, among others. In accordance with some embodiments is the realization that it is also important that, despite the aforementioned precision, the arrangement for hole formation can be highly flexible and that components known per se can be used. The embodiments of the present inventions also deal with this problem.

In accordance with an embodiment, one or more first cylindrical extension units can be used to determine hole direction. These units can be applied in a respective guide sleeve. One or more first drills with one or more first diameters can be directed by means of the respective extension unit toward the jaw bone and/or zygoma in said direction for forming an introductory hole extent with a respective first diameter. Finally, one or more drill guide units for one or more second drills with one or more second diameters can be inserted toward the bottom of the introductory hole extent for continued drilling.

In further embodiments, the first cylindrical extension units can be formed as cylinders with longitudinal and continuous central holes. The extension units can be two in number and can have different diameters for the holes. The drill guide units can be designed with cylindrical portions which have external diameters corresponding to the internal diameters in the respective guide sleeve and/or extension unit. The drill guide units can be designed with handle parts, which can make them easier to maneuver by hand. First drill guide units can be arranged to support second drill guide units in the same way as they themselves are supported in the guide sleeves.

The use of these embodiments can make it possible to achieve an efficient arrangement in which the risks of damage can be effectively avoided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

InFIG. 1, a drill template is indicated by1. The drill template has guide sleeves2,3which are applied with the aid of computer-aided equipment (not shown). The longitudinal axes of the guide sleeves, for example, a longitudinal axis2aof the guide sleeve2, are directed toward a solid part of a symbolically indicated zygoma4. In the present case, the template has two guide sleeves which are directed toward said zygoma part4on one side of the zygoma. A corresponding arrangement with two guide sleeves can be present for alignment with the other side of the zygoma.

FIG. 2shows a cylindrical extension unit5from the side. The cylindrical unit5has an external diameter D and an internal diameter d and is thus provided with an internal central hole (not shown inFIG. 2) extending in the longitudinal direction of the cylinder. The unit5has a length L. In some embodiments, the length can be approximately 30 mm. The diameter D can be approximately 6 mm, and the internal diameter d can be approximately 4 mm. Said unit5can be applied to the respective guide sleeve2,3which has an internal diameter slightly greater than the diameter D, i.e. the extension unit5can be inserted into the guide sleeve.

FIG. 3shows an extension unit6with in principle the same structure as the unit5inFIG. 2. The unit6has a structure corresponding to the unit5but has different dimensions. In one illustrative embodiment, the unit6can be applied in the sleeve2or3and can receive the sleeve5in its longitudinal and continuous central recess. Alternatively, the units5and6are exchangeable in said sleeve2or3.

FIG. 4shows two drills7,8known per se. The drill7can have a smaller external diameter than the drill8and can cooperate with the unit5according toFIG. 2, while the drill8can cooperate with the unit6according toFIG. 3.

FIG. 5shows two conventional drills9and10. The drill9can have a diameter of 2.9 mm and the drill10can have a diameter of 3.5 mm. These drill diameters can be substantially less than the drill diameters of the drills7and8according toFIG. 4.

FIG. 6shows exemplary embodiments of drill guide units11and12with cylinder parts11aand12avia which the drill guide units can be applied in either the units5,6or, in an alternative embodiment, directly in the guide sleeve2in the drill template. The units11and12also comprise handle parts11band12bby means of which the units can be applied in the central hole in question and which allow the units to be turned about the longitudinal axes of the parts11aand12a.

FIG. 7shows exemplary embodiments of second drill guide units13,14,15with a corresponding structure to that of the drill guide units11and12, but with different dimensions. In one illustrative embodiment, the units13,14and15can be applied directly to the guide sleeve (e.g. guide sleeve2) in the drill template. It is also conceivable to arrange these guide units13,14, and15so that they can be applied to the extension units5and6. In one embodiment, the guide units13,14,15can also receive the guide units11and12via their longitudinal central holes.

FIG. 8shows the guide sleeve2according toFIG. 1in diagrammatic form. An extension unit, for example the extension unit5, is applied in the guide sleeve2. Thereafter, a guide unit11(cf.FIG. 6) can be inserted in the continuous central hole or recess5aof the extension unit5via its guide part11a. The unit11is provided with a longitudinal continuous recess11cfor a drill according toFIG. 5.

FIG. 9shows another embodiment in which the unit13according toFIG. 7is inserted into the guide sleeve2in the drill template according toFIG. 1and the unit11is in turn inserted in the central hole of the unit13. It should be noted here that the guiding between the different components (the sleeve parts) is considerable and that the gap between two respective units is of the order of magnitude of 0.1 mm.

FIG. 10shows, in a diagrammatic representation, the insertion of the unit6in the direction of arrow14into the sleeve2in the drill template.

FIG. 11shows a hole being formed in connection with the sleeve2in the template1where the extension unit5is applied in the guide sleeve. The unit5guides a drill7(or8) via its longitudinal central hole5a. By means of the drill, an introductory hole extent is formed in the solid part of the zygoma4. The introductory extent has the length A and can be varied from case to case. The drill is driven by mechanical equipment (electric motor)15of a type known per se and in a manner known per se. The equipment15rotates the drill about its longitudinal axis16, for example in the drilling direction17.

FIG. 12is intended to show the stage where the hole formation is completed following the state shown inFIG. 11. The extension unit5has been replaced here by the drill guide unit13(seeFIG. 7) which assumes the position shown inFIG. 12in the guide sleeve2of the drill template1. In this case, the drill9according toFIG. 5is used, which drill can thus be guided by the unit13and move to the bottom18of the hole19formed by the drill7. The end of the drilled hole19is cone-shaped and the drill9in this way acquires a locating function. InFIG. 12, the continuation of the hole formed with the drill9is indicated by broken lines20. In the present case, the drill has been allowed to penetrate slightly out of the zygoma4, with the result that the drill can be felt by the fingers through the patient's skin22outside the zygoma.

It will be appreciated that the drill hole formation can be carried out in stages with different drills of different diameters. Thus, the hole19can be started with the drill17according toFIG. 4and completed with the drill8according toFIG. 4. Correspondingly, the drills9and10with the different diameters can be used for forming the hole20. It will also be appreciated that different configurations and dimensions can be used on the drill guide units11-15. The hole parts19and20formed can subsequently be threaded with a thread tap (not shown) in a manner known per se. InFIG. 12, the drive equipment for the drill9is indicated by23, which drive equipment can be of the same type as the drive equipment15and for example can comprise a drill machine, screwdriver, etc. The longitudinal axis is indicated by24in the case according toFIG. 12, while the direction of rotation is indicated by25.

In accordance with an embodiment, the drill guides10,11according toFIG. 6can be used on an instrument (not shown) by means of which it is possible to indicate and mark out on the patient's skin outside the zygoma the drill end of the drill which is used for forming the hole20. Said instrument is described in more detail in an application submitted on the same day as the present application and by the same Applicant as for the present patent application. Said instrument is designed with a sleeve-shaped fastening or anchoring part which can extend in the guide sleeve in the drill template. Each of said units10,11can thus be inserted by way of its cylindrical part into the sleeve of the instrument and the precision or play between the parts is of the same order of magnitude as has been described above.