Description

The invention refers to the dentistry, particularly bicortical dental implants for the fourth type of jaw bones, in particular for premolar and molar areas of maxillas.

It is known that bicortical installed implant in maxillas has direct contact with the mucous of maxillary sinus (antrum), i.e. Schneider's membrane. Most currently available implants surface designs, even ones with the rounded corners, including sandblasted, Large or Small Grit, Acid- Etched and so on cause the intrusion and eruption of the implant into the sinus. The only rare exception is a polished tip (apical part).

The manufacturers and doctors, particularly dentists and otorhinolaryngologists should pay special attention to the design of this part of the implant. / 1 /.

There are also known both prefabricated and adjustable basal implants which do not use the precision hole preparation technique, have the unpredictable final position of an implant and uncontrollable pressure on different areas of adjacent bone. Such consequences can cause long-term complications with using the biochemical installation technique and therefore using similar implants should not be recommended for bicortical fixation. 1 2 1

It is also known that the standard cylindrical shape implant installed using bicortical technique weakens the structure of the upper jaw, and consequently often causes eruption, perforation and intrusion complications. In the proposed bicortical dental implants, these complications are ameliorated hence proposed design eliminates the cylindrical shape of the implant as a complicating factor. Firstly, due to the diameter of the first ring (rim collar) which is bigger than a semi-spherical or two coupled elliptical-paraboloid ledge shape apical portion. Secondly, due to the precision drilling and positioning technique with last ring (rim collar), fixed in the cortical table of alveolar ridge of maxilla orally. / 3 /

It is also known that the driven (hammered) into jaw implants also do not provide predictable and accurate final position since currently, it is not possible to predict and measure the strength and direction of every drive (kick) in all cases / 4 /.

The precisely controllable positioning of implants becomes available with developing of precision drilling and hole preparation. Hence, uncontrollable change of position and pressure on the bone walls of the hole in the permanent positioning stage is minimized. Overheating, overloading and breaking of the bone structure must be avoided, especially in the areas with lost of the alveolar bone and in cases when implants are installed in basal parts of the jaws and other cranial bones. This is highly important in areas where bone volume is low. For example, the bone volume in upper posterior teeth areas is limited to the maxillary sinus (Antrum) floor, with attached to it Schneider membrane from the top and alveolar bone, formed after teeth extractions, with gingiva from the bottom respectively. These alveolar bone losses most of its value due to teeth extractions, operations, or other processes. Resorption is going on in every direction of the jaw bone, mostly in vertical (apically I.e. The short implant lengths) and horizontal (vestibulo-orally, I.e. Narrow implant diameter) directions. In these cases, the bicortical position of an implant makes possible to increase both primary and permanent stabilization of an implant.

Technical breakthrough of the invention is the precise final position of the dental implants in the jaw bones, accomplished by an improved geometrical shape that minimizes trauma, ameliorates complications and results in rapid healing.

The technical breakthrough is accomplished by the polished surface of its first and last rings (rim collars) and right- or left-handed tapered-thread with parabolic shaped volutes (Fillet turns). The bicortical dental implant is presented on 10 figures.

Fig. 1 - depth stop rings set for precision hole preparation technique; Fig. 2 - bicortical dental implant, shows a front (polished portion's) view; Fig. 3 and 4 - shows bifurcated apex portion of implant schematically; Fig. 5 - schematic view of Schneider membrane's structure with "cilia" presenting its function;

Fig. 6 - bicortical implant, shows a side view;

Fig. 7 - X-ray image of standard or fifteen-sized "tripod";

Fig. 8 - The whole framed bridge for direct loading;

Fig. 9 - Right- and left-hand bicortical implant of upper jaw with corresponding 1 and 2 markings; Fig. 10 - Right- and left- bicortical implant of the upper jaw and hand chart scheme, indicated directions of the thread.

Precision drilling sets with depth stop rings must be applied to install implant accordingly to planned in advance position of the implant, based on CBCT (Cone Beam Computer Tomography) images and with visual control. For example, applying endoscope to observe the walls of a hole or other controls. On this stage result of precision drilling bottom of the hole remains the thinnest membrane. Using implant with an aggressive tip can cause ripping of the membrane and eruption in the maxillary sinus, even in ideal preparation with modern technologies. It is proposed to use an implant with special design in these cases, with the polished apical part, which naturally resembles tip of the apical part of the tooth. In wide (with the diameter more than 3.5 mm) implants tip has a design of bifurcated root apexes. This design allows mucosa of maxillary sinus to continue its function and not disrupt fluid flow and beating of cilia remarks undisrupted. Recommended design with a not aggressive type of thread has to be used with type IV bone, which is mainly presented in posterior teeth areas in maxillas. In contrast to classic thread design, rings are more expressed and the step is longer. An example of this ratio is presented in an image and may be manufactured with different scale and acceptable deviation.

In cases where straight, angled (15 degrees) abutment or "tripod" constructions are used it is proposed to use one stage method ( the form of one piece implants on image) with immediate loading and permanent binding with whole bridge frame. For example, whole cast or milled frame.

It is also proposed to use the different direction of threads for implants on left and right sides. Taking into consideration type of chewing pressure for posterior maxillary teeth, in based on their position and relationship with antagonists. For example, in first class upper right molar of the working side in lateral movement causes reciprocative revolve movement of the implant with right thread can cause losing implant due to its thread design. Accordingly to the side and crown surface relief implants in this regions are recommended to be chosen with provided guideline: posterior left side maxillary molars with right side thread, and right posterior maxillary molars with left thread design. Numerical (1 for the right and 2 for the left) accordingly to international classifications and teeth number) and colored label (Red - Right thread, Lemon - Left thread) with right and left hands images on the boxes should be applied. This will allow doctors to remember, that 1 =Red=Right for left upper teeth of the patient and in classic working position "face-to-face", chair in the vertical position for the doctor same, Right side. And opposing to the left. Left and Right threaded implants must be designed intentionally incompatible to exclude possible wrong rotation by medical personnel.

In contrast to other available implants, the bicortical dental implant is safer through the proposed design, which does not complicate much the manufacturing process.

Classification(Codes)

IPC: A61 C8/00

CPC: A61 C8/0012, A61 C8/0013, A61 C8/0018.A61 C8/0098