Drilling guide for dental implantation

An adjustable drilling guide, removably mountable to a patient's teeth, having a guide block with at least one stent for guiding a dental drill is disclosed. In a first embodiment, the guide block has a plurality of guide holes disposed at differing angles which may receive a stent for precise drilling at the selected angle. If minor variations need be made, the stent may be moved to a second or third of the guide holes to adjust the angle. In a second embodiment, three distinct stents are formed directly in the guide block allowing for drilling at up to three different angles. A third embodiment has a stent which is pivotable about a pivot point within the guide block, allowing drilling at any angle within the arc of the pivot. The guide block may be fitted to a model of the patient's teeth prior to installation into the mouth to ensure proper fit.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to guides for drilling into a patient's jawbone for insertion of a dental implant. More particularly, the invention comprises a unique guide which allows for minor corrections in the angle and location of entry which are not typically possible with currently available guides.

2. Description of the Prior Art

In dentistry, it is often necessary to implant prosthetic devices, such as artificial teeth. This procedure requires the implantation of an anchor into the jaw, and then the attachment of the prosthetic to the anchor. Typically, the anchor is implanted by drilling into the jaw bone and screwing, or otherwise attaching the anchor into the bone. Proper alignment of the implanted anchor is necessary to ensure that the prosthetic aligns properly with the patient's natural teeth. One method of ensuring proper alignment of the anchor is by making an impression of the patient's mouth structure, fitting a drilling guide to the impression and creating a mold around the guide such that the mold may later be fitted to the patient's natural teeth. The primary drawback to this method lies in the existing art of the guides, in that only a single channel is provided for directing the drill. If the angle of that channel is off, even slightly, a good bone contact may not be possible. In this case, a new guide must be fitted, generally requiring a delay of the procedure, perhaps for several days. The present invention overcomes this problem by providing a plurality of channels so the angle may be altered should the need arise.

U.S. Pat. No. 5,851,207, issued to Morris D. Cesarone on Dec. 22, 1998, presents a FREELY SEPARABLE SURGICAL DRILL GUIDE AND PLATE, in which a drill guide is mounted a the tip of a manipulable forceps type tool. Unlike the present invention, alignment depends on the immediate judgement and steadiness of hand of the user.

U.S. Pat. No. 5,833,692, issued to Israel Abrahami on Nov. 10, 1998, presents a DRILL GUIDE having a locating pin which must be inserted into a hole drilled into a patients mandible and an adjustable guide block for guiding the drill. By contrast, the present invention requires no drilling into the mandible to secure the device and provides specifically aligned drilling paths.

U.S. Pat. No. 4,306,866, issued to Bernare Weissman on December 1981, presents an ADJUSTABLE DENTAL DRILL GUIDE wherein a drill guide is secured in a hole drilled into an adjacent tooth. By contrast, the present invention requires no drilling of healthy teeth for securing the guide.

U.S. Pat. No. 4,045,874, issued to Richard C. Roman on Sep. 6, 1977, presents a DENTAL DRILL GUIDE ATTACHMENT attachable directly to the dental drill. The guide of Roman is manually held in place on the work surface (tooth or mandible), while the guide of the present invention, is formed to a mold of the work surface and then transferred to the work surface in a secure manner, thereby allowing more precise drilling.

SUMMARY OF THE INVENTION

As has been previously stated, the implantation of oral prosthetics requires a drilling into the jaw bone at a relatively precise angle in order to implant an anchor device to which the prosthetic is attached. The present invention presents a drilling guide which enables the dentist or oral surgeon to drill at the precise angle, if not on a first attempt, at least without having to refit the patient with a second drilling guide. The present invention presents a guide having a plurality of guide paths by pivoting the stent to different angles, allowing for adjustment of the angle of attack for better alignment of the implant.

Accordingly, it is a principal object of the invention to provide a dental drilling guide which is economical to use.

It is another object of the invention to provide a dental drilling guide which is easy to install in a patients mouth.

It is a further object of the invention to provide a dental drilling guide which is easy to use.

Still another object of the invention is to provide a dental drilling guide which provides a precise angle of entry.

An additional object of the invention is to provide a dental drilling guide which allows for multiple angles of entry within a single guide unit

It is again an object of the invention to provide a dental drilling guide which incorporates a depth guide in addition to angle guide.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The drilling guide of the present invention comprises two basic elements, a stent and a guide block, or in alternative embodiments a guide block having integral stent(s), each of which will be set forth individually hereinbelow.

Referring first toFIGS. 1 and 2, the stent10is depicted as being a hollow cylinder12, having a smooth interior wall14and a striated exterior wall16. The striations18are evenly spaced, circumferentially, along the length of cylinder12, thereby providing a plurality of convenient points for adjusting the length of cylinder12, and thus establishing a desired length of stent10.

FIGS. 3thru11, collectively, depict three separate embodiments of guide block20which may be affixed to an occlusal surface of a jaw, typically by light curable resin or other means. The construction of each embodiment of guide block20will first be described, followed by a general description of the method of use for all of the embodiments.

Referring first toFIGS. 3thru6, guide block20has a substantially rectilinear block21having a proximal, substantially flat end22and a distal, slightly convex end24, and four sides26. A first round guide hole28is bored from a center point of proximal end22, substantially parallel to the four sides26, to a point at a predetermined distance from distal end24. A round base guide hole30, having a longitudinal axis coinciding with that of first guide hole28and a diameter slightly smaller than that of first guide hole28extends from the bottom of first guide hole28to distal end24, thereby forming a stent stop32at the base of first guide hole28, thereby preventing stent10from passing fully through guide block20. A second round guide hole34and a third round guide hole36, each having a diameter substantially equal to first guide hole28, are bored from a point on first end22proximate each of two opposite sides26, respectively, to stent stop32proximate the center of base guide hole30, the centers of first guide hole28, second guide hole34and third guide hole36being alined with one another. The three borings of first guide hole28, second guide hole34and third guide hole36overlap such that each is open to the other along its length. Stent10is slidably insertable into any one of guide holes28,34and36to a point of contact with stent stop32.

While guide block20has been referred to as substantially rectilinear, it would evident to one skilled in the art that others shapes could be utilized with equal effectiveness. Likewise, while guide holes28,34,36have been referred to as substantially round, it would be evident to one skilled in the art that other shapes having a “regular perimeter” which hold stent10in a stable manner may also be used. For the purposes of this application, “regular perimeter” is defined as a circle or any other shape configured to hold a stent in a stable manner. It would be further evident to one skilled the art that the alignments of guide holes28,34,36may also vary slightly from the above without adversely affecting the concept of the invention. The above applies equally to the embodiments described hereinbelow.

Referring now toFIGS. 6thru8, guide block120is again a substantially rectilinear block121having a proximal, substantially flat end122, a distal, slightly convex end124, and four sides126. A first round stent128is bored from a center point of proximal end122to a center point of distal end124. A second round stent134and a third round stent136, each having a diameter substantially equal to first stent128, are bored from a point on proximal end122proximate each of two opposite sides126, respectively, to a center point of distal end124, the centers of first stent128, second stent134and third stent136at first end122being alined with one another. First stent128, second stent134and third stent136begin as individual borings at first end122, but terminate at distal end124, their axis intersecting at a single point.

Now moving toFIGS. 9thru11, guide block220is once again a substantially rectilinear block221having a proximal, substantially flat end222and a distal, slightly convex end124, and four sides226. A slot228, presenting a substantially rectangular opening in proximal end222, is formed in the interior of block221. A pair of opposite walls230of slot228are formed substantially parallel to and spaced apart from two opposite sides226of block221and substantially normal to first end222. A second pair of opposite walls232of slot228are formed substantially parallel to the remaining two opposite sides226of block221, tapering inward and downward from the lines of abutment of first end222and sides226to a point proximate center of second end224, terminating in a substantially rectangular opening234in distal end224. Opening234has dimensions substantially equal to the diameter of a hollow, tubular stent240which is disposed within slot228such that a proximal stent end242extends slightly above proximal end222of block221while a distal stent end244extends to opening234in distal end224of block221. Stent240pivots about a pivot245comprising a pair of pivot pins246disposed on opposite sides of stent240proximate distal stent end244and fitting into pivot holes248in the interior of slot228proximate opening234. By pivoting about pivot pins246, stent240may be angled from one extreme edge of proximal end222to the opposite, extreme edge of proximal end222, thereby altering the angle at which distal stent end244is presented in relation to distal end224of block221. It would be evident to one skilled in the art that pivot pins246and pivot holes248could be reversed such that pins246formed in slot240engage holes formed in stent240and that pivot pins246could be of a shape such as, but not limited to, hemispherical or similar, without departing from the spirit of the invention.

For simplicity of explanation of the method for using the drilling guide, the embodiment ofFIGS. 1thru5will be used, with variations described subsequently.

In preparation for dental implantation using prior art drilling guides or stents, an impression is typically made of a patient's mouth and a plaster cast made of the impression. A guide is formed to the plaster cast in such a way that it bridges between the teeth on either side of the implant site and the guide hole in the guide is aligned for the proper angle for drilling into the patient's jaw for implantation of an anchor for the prosthesis being fitted. The drilling guide is then transferred to the patient's mouth and bridged between the patient's own teeth, typically securing it with curable resins or plastics. The dentist or oral surgeon then places a dental drill into a stent the guide hole for drilling at the proper angle and at the proper depth. Heretofore, if the angle of drilling was not quite right, the entire fitting procedure had to be redone, causing delays in the implantation.

With the present invention the impression and casting are carried out as before and the drilling guide20is fitted to the casting, typically with a curable resin or plastic. Stent10is cut to the desired length at one of the striations18and then fitted into the central guide hole28until it strikes stent stop32. The dentist then places the drill into the core of stent32and drills to the prescribed angle and depth. If he finds that the angle was not quite right, he withdraws stent10from central guide hole28and reinserts it into either guide hole34or36to adjust the drilling angle. On completion of the drilling, the drilling guide20is removed from the teeth.

In the second embodiment ofFIGS. 6thru8, the same procedure is followed, with the exception that stent110is incorporated into drilling guide120, as stents128,134and136. In the embodiment ofFIGS. 9thru11the pivotable stent240serves the same function of adjustability.