Purpose and types of surgical templates. Dental implantation according to navigation templates. When a template is needed

The intensive development of advanced technologies has contributed to the fact that patients are no longer afraid, as before, to decide on a radical restoration of their teeth with the help of. This process has long been considered safe, but only if two conditions are met: a competent specialist performs the work, the clinic is equipped with modern equipment, which can also be used to make surgical templates for dental implantation.

In this article, we will analyze in detail what template work is in implantology and find out what are the advantages of using innovative devices for treatment at the highest level.

It is interesting! Today, techniques using templates are also called “template implantation”. This word itself is of English origin and is translated precisely as a “template”.

What is a surgical guide

To a simple layman, it will seem that this is an ordinary transparent mouthguard, similar to the one used to protect teeth in traumatic sports or to correct an overbite. It is the external difference that lies only in the fact that in this kappa there are holes that have the same diameter.

But for the implant planner, the surgical template is much more than just a mouthguard. This is an auxiliary tool or guide created according to the individual data of each individual patient for precise positioning of implants.

With the help of this device, the doctor can install implants into the jaw bone tissue with an accuracy of up to a millimeter. Moreover, this can be done quickly and minimally invasively even in complex clinical cases, for example, in acute bone tissue atrophy.

Important! The use of such a template in practice allows you to protect not only the doctor himself, but also the patient. Accurate placement of implants eliminates any risks associated with trauma to the sinuses and nerves, as well as complications. So the result will not bring disappointment.

Manufacturing process

The production of templates for implantation can only be carried out on high-precision equipment (CAD / CAM technology or 3D printers) and with the help of the most modern computer software, which involves a preliminary process. Most often, this can be done in a dental laboratory, which is attached to dentistry.

How to make a template taking into account all the individual anatomical features of the patient's jaw? For this, the implant surgeon does not work alone. This requires the coordinated work of a team of professionals. In addition to the implantologist, an orthopedist is also involved in the work. Together they pre-prepared for dental implantation. The patient is required to pass a CT scan of the jaw and undergo the procedure for taking casts.

Next, the resulting casts are scanned and volumetric modeling. At this stage, specialists work out a treatment plan directly in a computer program, select models of implants and determine the place for their installation. When all the data obtained as a result of diagnostics is taken into account and worked out, the template itself is created on their basis.

« Experienced specialists must clearly understand that for each manufactured dental implant surgical guiderather stringent requirements. This is primarily the necessary rigidity and strength. The product should be securely fixed in the oral cavity, as close as possible to the gums or teeth. It should accurately repeat the anatomical features, the natural curves of the alveolar ridge. And of course, the guides must, with an accuracy of up to a millimeter, indicate the place for positioning the implant. It is not easy to achieve such indicators, only professionals can do it, but without these conditions, the success of implantation is already being called into question, especially in very difficult cases.”, - says V.A. Way, an implant surgeon with more than 20 years of experience.

Materials and types

Design principles for dental implant templates are based on safety, hypoallergenicity for the patient and simplicity, ease of manufacture and convenience of sterilization for doctors. Products in the manufacturing process should be easily processed and affected, so they are created from materials such as acrylic, transparent plastic, medical polymers (plastic).

As for the types and options for using the templates, they can also be different for each individual clinical case: they can be based on the patient’s jaw bone tissue in difficult situations (when it is required to perform a flap operation during the installation of implants) or on the mucosa in multiple, complete edentulous. There is also a separate type of templates based on preserved teeth.

Important! Doctors also distinguish varieties of guides (these are holes in the templates), which are created for a special tool with which the surgeon will work during the implantation process. Those. the diameters of the holes in the templates can also be different depending on the type of drills and keys, as well as on the technique that the specialist practices.

There are also standard templates. Or rather, guides. They look like labeled plates - these are most often used for standard protocols, for example, all-on-4 () or when the installation of implants is known in advance (that is, if the patient has an ordinary case).

When you can't do without an implantation template

Consider situations in which the manufacture of a guide template for implantation is simply necessary:

• the patient is missing a large number of teeth or there is complete adentia: when a complex restoration of teeth is expected and the installation of several implants at the same time. In this case, the specialist needs special guidelines for the installation of implants, without which it is very easy to make a mistake,
• if the teeth are restored with the use of . In this case, the installation of implants and prosthetics are carried out in the shortest possible time, i.e. The patient receives a dream smile in a few days. Therefore, the doctor simply cannot have the right to make a mistake, and navigation templates that are created at the stage of careful treatment planning help to eliminate risks, just the same.
• atrophic processes in the bone tissue: surgical templates allow dental implantation without additional bone augmentation operations. Through guides, the doctor avoids “weak” areas in which the bone is thin and will not withstand the subsequent load from prostheses, as well as the maxillary sinuses in the upper jaw and the trigeminal nerve in the lower,
• it is necessary to restore the teeth located in the frontal zone of the smile: there are increased aesthetic requirements for implantation of teeth and prosthetics in this area, and in order for the smile to look beautiful and natural, it is simply impossible to do without precise positioning of artificial roots.

On a note! Experienced surgeons have long appreciated the advantages of template designs in dental implantation. But there are situations when their use is not possible. In particular, they cannot be fixed in the mouth with anomalies of the maxillofacial apparatus, with macroglossia, when a person cannot open his mouth wide.

What are the benefits of template constructs?

Creating an individual surgical template for dental implantation allows the patient to be sure of a good result of treatment, and, as mentioned above, to protect himself - the likelihood of errors during treatment is reduced to zero. In addition, the guides greatly facilitate the course of the procedure for installing implants, and their use provides many more advantages:

• fast surgical stage: the doctor tightly fixes the template on the patient's jaw and performs his work through the guides. This approach saves a lot of time
• bloodless implantation: the implantation of implants today in most cases is minimally invasive. This means that the doctor will not carry out exfoliation of the mucous membrane and large-scale intervention, even if a large number of teeth need to be restored. Through the holes in the template, the specialist will make a puncture. As a result, such a puncture heals more easily afterwards, facilitating the patient's rehabilitation period. There are no unnecessary sutures, bleeding, pain, traumatic injuries of soft tissues,
• after the installation of implants, you can immediately install a prosthesis: with the help of guides, the doctor can immediately fix a temporary and even permanent crown or prosthesis, which will be ideally positioned on artificial roots.

What are the disadvantages

There are several nuances that need to be mentioned.

The first is that it may take several days to carefully study the treatment process and make a template. But in modern realities, given that a patient can get new teeth today literally in a short period of time, these are mere trifles. In addition, the presence of a template reduces any risks from implantation procedures to a minimum. So it's worth the wait for that.

The second is that you can entrust the creation of a template only to a specialist who is fluent not only in innovative implantation techniques, but also in perfect knowledge of the anatomy of the maxillofacial apparatus. Also, the doctor must be able to use computer programs, but not only at the user level. He must constantly improve his skills (and confirm this with official documents, certificates) in order to keep up with the times. But unfortunately, there are still quite a few such specialists even in the capital of our country.

In dentistry, a surgical template is a capu-stencil with holes for embedding implants, made using digital technology. With its help, prostheses are mounted in the right place, carefully selected on the computer, at the right angle to a certain depth.

Prices for the manufacture of a surgical template

Examination on diagnostic models of the jaws (surgical template) 5750 P

Surgical Template Specialists

Andrey Albertovich Pastyan

1994-1999 - Ukrainian Medical Dental Academy (UMSA).

1999-2000 - Clinical internship: Dr. Flussenger's clinic in Friedrichshafen.

2000-2001 - Clinical internship at the UMA of postgraduate education. Shupyk, Kiev "Chair of the ChLH".

What is a surgical template for?

With the help of a surgical template, the specialist positions the placement of the prosthesis as accurately as possible during its installation, 100% does not make mistakes that are often found in classical prosthetics.

When is a template needed?

In dentistry, a template is required in the following cases:

1. when there are no teeth on the lower and upper jaw. The specialist does not have a guide to better understand the placement of teeth in the patient's jaw for implant attachment;
2. if you need to restore anterior teeth that are missing. Here, the manufacture of a surgical template is necessary for ultra-precise placement of implants. The front teeth are subject to excessive requirements regarding the index of aesthetics.

Several videos about surgical templates

Types of templates for dental implantation

To date, Moscow clinics offer several types of surgical templates, which differ from each other in the materials used and production methods:

• acrylic (similar to a denture having a gum base);
• polymeric;
• transparent (created in a vacuum former);
• surgical templates created using CAM|CAD digital modeling.

Manufacturing sequence

The manufacture of a surgical template for dental implantation includes a number of sequential steps:

• Stage 1.

  preparation of the oral cavity for implantation, diagnostic work. The places where the implants will be installed are planned, and what kind of smile will become;

• Stage 2.

  creating an impression of the hard tissues of the jaw. Thanks to him, places for implanting titanium implants will be determined;

• Stage 3.

  placement of implants in the designated holes.

Photo with examples of surgical templates

Advantages

The advantages of placing implants when using a surgical template include the following:

• accurate implantation of the missing tooth, eliminating errors;
• installation of prostheses using a surgical template allows you to get a high aesthetic smile;
• the template serves as an assistant for a doctor who needs to install an implant in a patient with malocclusion.

The surgical template for implantation has no disadvantages, except for the relatively high price of the procedure due to the use of computer modeling and a 3-D printer. In this case, the cost depends on the method of manufacture, the materials used and some other factors.

Implantation in dentistry is one of the fastest growing areas associated with artificial restoration of teeth.

Huge financial resources are invested all over the world in the development of new technologies and materials, new projects are constantly being opened.

The result of such work is high-quality assistance to each person in eliminating his problems, based on clinical, anatomical and financial capabilities.

Purpose

Implantation is considered a complex dental operation, and in order for it to be successful even in the most difficult cases, a specialist can use a template during it.

The device greatly simplifies the work of the doctor, helps to calculate all the nuances of the operation even at the stage of planning the operation. The likelihood of complications during implantation and upon its completion is excluded.

The use of the sample allows manipulation with minimal trauma, since the surgeon does not make unnecessary incisions.

The template is made individually for a particular patient using a scan of the impression made during the examination. In appearance, this is a special mouthguard with holes that are designed to accurately indicate the places of implantation of implants.

The device very accurately repeats the shape and curve of the jaw, as a result of which a sufficiently tight fit to the gum is achieved and the absence of errors during drilling. In the manufacture, materials such as a polymer component, plastic or acrylic can be used.

Indications

The use of a template guarantees almost 100% implantation success. It becomes necessary in the following cases:

1. Difficult implantation with complete edentulous when it is necessary to install several implants at once.
2. Bone atrophy when the template helps to accurately place the structure in the place on the jaw that will withstand the load without plastic surgery.
3. Operation with immediate loading when a temporary crown is placed on the implant immediately after implant placement.
4. Prosthetics on 4 or 6 implants, i.e. using all-on-4 or all-on-6 protocols.
5. High demand for aesthetics, i.e. when implantation is performed in the frontal region of the dentition.
6. The need for drilling at a large angle of inclination.
7. Needs for non-flap surgery.
8. It is planned to install a conditionally removable or fixed beam structure.

Contraindications

The technique is unique, since the list of restrictions for its implementation has been reduced to a minimum. It is suitable even for those patients who have a history of diabetes mellitus, chronic endocrine and cardiac pathologies in the stage of incomplete or complete remission (with a significant weakening or complete disappearance of the main signs of the disease).

Important! A contraindication in which it is impossible to perform an operation with a template is an insufficient amount of bone tissue in the area of ​​implantation and oncology of any organ or system.

Specialists in a separate group made restrictions that, under certain conditions, may prevent the use of the template:

• macroglossia, which is accompanied by insufficient opening of the mouth and nausea;
• dense tissue structure at the site of implantation;
• difficulties with fixing the device;
• implantation of an artificial root at an angle.

Material

Templates are made for each patient, i.e. individually. They can be done in a special outsourcing center equipped with high-precision equipment or in a dental laboratory.

Depending on the type of manufacture and the material used in this process, surgical templates are of the following types:

1. Acrylic. In their production, a polymer is used - acrylic mass. They are made in the laboratory in the image of a removable prosthesis.

   An impression is made in the clinic, a technician is sent to the laboratory, a model is cast, according to which a template will then be made. Acrylic product in dental practice is used most often, because it has an affordable cost.

2. Transparent. A product made of a special transparent plastic in a vacuumformer, so it is almost invisible. Today it is used extremely rarely due to the softness of the material, but this quality does not affect elasticity, stability and strength.
3. Plastic. For them, a medical polymer is used, which is characterized by a high degree of stability, strength, rigidity.
4. CAD/CAM templates using digital simulation. Devices are made on high-precision equipment.

   An impression of the patient's jaw is taken, which is then processed on a digital scanner. After that, all the data is sent to a computer, where the program carries out a step-by-step planning of the operation, selects the parameters of the implants, determines their implantation sites and angles of inclination.

   Prepared calculations are transferred to the machine for the manufacture of the template. This type is rarely used, since the use of high-precision equipment in its manufacture increases the final cost.

Important! Regardless of the material and method of manufacture, each of the templates is securely fixed in the oral cavity, convenient to use, and allows easy and extremely accurate implant placement.

Kinds

For implantation, one of three templates can be used by the dental surgeon:

1. Based on bone. The product is modeled according to a 3D sample on a computer tomograph. The manufacturing process itself takes place on stereolithographic equipment.

   Of all the types, this design is the most accurate, because it relies on the bone. But at the same time, the technique of the operation provides for the exfoliation of a large tissue area, which increases the duration of the postoperative period.

2. Based on adjacent teeth, moreover, there should be 2 units on each side of the restored area. This device is used more often than other options. To achieve its accuracy, a jaw impression, its three-dimensional (3D) model and CLTC are used.
3. Based on the gum (mucosa). The main indication for the use of such a template is total edentulism or very few remaining natural teeth.

   With the latter option, one more auxiliary step is required - the preparation of a radiopaque sample. On it, the surface of the mucous membrane and the proposed area for the installation of new teeth are well visualized. It helps to accurately and in great detail plan the course of the upcoming operation.

Templates are also divided into subspecies:

1. For pilot drill. Such a subspecies of the device is specially made for a surgical drill for any design of implants with a diameter of up to 2.0 mm.

   This method allows you to use the design without extra spending on special tools and auxiliary samples.

2. For all drills or a special key. This option is necessary if you want to make several drillings with drills of different diameters, but under the control of only one template.

   This procedure takes place in two ways - several samples are ordered for each type of bur, or several keys are used and only 1 template is made.

   The keys are inserted into the fixture in turn, changing the diameter of the inlet holes. This subspecies is the most expensive, because it involves the use of a large number of devices.

3. Under the full protocol. Of all three varieties, this option is considered the most reliable. During implantation, all manipulations are performed according to one template.

   On the one hand, this is very convenient for the doctor, but on the other hand, the cost of the operation increases due to the need to purchase a new extended set for the template.

Important! What type and type of device will be used during the operation, the implantologist decides, based on the indications and the complexity of the case.

Primary requirements

Regardless of what material the template is made of, and what particular method was used, each of them must meet certain requirements:

• must have sufficient rigidity and a high coefficient of strength;
• clearly indicate the location and inclination of the future implant;
• securely held in the oral cavity;
• fit snugly to the gum or be fixed on the remaining teeth;
• accurately copy the anatomy of the jaw;
• convenient to sterilize.

Manufacturing process

In order for the implantation with a template to be successful, a team of highly qualified specialists, consisting of an orthopedist, dentist and a practicing surgeon, must participate in its creation.

The manufacturing process takes place in stages:

1. Training. It includes conducting a general diagnosis of oral health, obtaining an assessment of the clinical picture of the defect using computed tomography. The last examination is necessary to select the optimal type of prosthesis and determine the place for implantation of implants.
2. Removal of casts from the jaw. This is a mandatory procedure before any method of prosthetics. It is carried out even in the complete absence of chewing elements in a person.
3. Volumetric (3D) modeling. The formation of a 3D version of both jaws is carried out after scanning the cast taken based on the information received during the diagnosis.

   The computer program develops the course of the upcoming procedure, determines the location of the prostheses on the jaw, sets the desired slope and creates a projection of the future product.

4. Expected Result. At this stage, a person can see the expected result of the operation.
5. Create a template. This process takes place either in the laboratory or in a specialized center on high-precision equipment using cad / cam tools.

   In the first option, the dental technician does all the work manually, in the second, the whole process takes place on a computer and a 3D printer.

Advantages

Now, few practicing highly qualified implantologists perform surgery without a surgical template. The device allows the doctor to perform all manipulations faster, better and more accurately, which is not always possible to perform without a sample even for experienced surgeons.

At the same time, the product greatly simplified the work of a specialist, minimized the risk of developing unpleasant consequences and complications, and the operation itself became less traumatic, since it completely eliminates the need to make large and unnecessary dissections of soft tissues.

For the specialist and his patient, the design has certain advantages. These include:

• extremely precise implantation of the rod;
• eliminates the possibility of a surgeon's error;
• rejection is reduced to zero;
• reduced operation time;
• tissue damage is minimal;
• short recovery period. Recovery is better tolerated by the patient, there are no pains and complications;
• in advance, the patient can see and examine the result in detail at the preparation stage;
• it is allowed to fix the crown immediately after the completion of the procedure for implanting the system;
• in one operation, several rods can be implanted at the same time;
• the template can be used as a support for temporary systems.

The technique of implantation using a surgical template is presented in the video.

Flaws

No direct flaws related to the device itself have been identified. Only its indirect disadvantages are indicated:

• the process of creating a template involves increasing the total duration of the entire prosthetics by 2-3 days;
• the patient is required to pay additional financial costs associated with the payment for the production of a surgical sample.

Expert opinions

The position of implantologists regarding the rationality of using the template is practically the same. The success of prosthetics is determined by several factors that affect the course of the procedure and its result.

The performance criterion is determined not only by the quality of the preparatory work carried out and the choice of the appropriate implant option, but also by the professional approach to implantation, its planning and the availability of additional devices that help in the work.

It is to such devices that the surgical template belongs. Allowing the specialist to ideally select the place of attachment of the artificial organ, the product helps him calculate the course of the operation, without diverting the doctor's attention to unnecessary manipulations.

The template gives the specialist confidence in the favorable outcome of the operation and further improves his psychological mood.

Dental implantation is a precise procedure that does not tolerate approximate calculations. When installing implants, a deviation from the intended position even by 1-2 millimeters can adversely affect the effectiveness of treatment, and the surgeon's work "by eye" can result in complications for the patient. The innovative 3D-pattern implantation technology allows you to place implants, and then a prosthesis, with pinpoint accuracy. The orthopedic doctor of the StomArtStudio Leonardo clinic Vasiliev Leonid Alekseevich talks about the features of creating and using a 3D template.

How does traditional implantation work without a 3D template?

During a surgical operation, the doctor cuts the gum, folds back the flap, gaining access to the jawbone. Then, using a special tool, he makes a recess in it and carefully installs an artificial tooth root - an implant, after which he sutures the wound. This approach is too traumatic and involves a rather long period of wound healing.

The doctor determines the places for implant placement on the basis of a panoramic x-ray (orthopantomogram), digital models of the jaws, and computed tomography data. At the same time, the planning and conduct of the operation largely depends on the professionalism and experience of the surgeon. To avoid possible errors during implantation, reduce its traumatism and reduce the procedure time, scientists and dentists have developed a technology for installing implants using a 3D template.

What is a 3D template?

This is an individual model of the patient's jaw, created from biocompatible materials. On it, taking into account the angle of inclination, the exact places for the installation of implants are marked. Implantation takes place strictly according to this template. Before making it, the patient is given a CT scan, then the doctor takes casts of the jaw.

After drawing up a treatment program (choosing a model of implants, their number, and so on) and agreeing it with the patient, the modeling stage begins. With the help of a computer program, the surgeon chooses the optimal places for placing implants, taking into account the volume of the jawbone, the location of nerves, blood vessels, and maxillary sinuses. This avoids damage and injury during subsequent implantation. The doctor determines the size of the implants, the depth of installation, the angle at which they should be located in the bone. Work on the template takes only a couple of days. Its result is the model itself, created on a 3D printer from a biocompatible material. The template is sterilized before implantation.

3D implantation is indicated in cases where the patient needs to fix three or more implants in one visit. We also recommend this technology when placing one or more implants with immediate loading, for example, in the prosthetics of the anterior teeth. The 3D template also helps to perform implantation in patients with bone atrophy.

How is 3D implantation carried out?

The surgeon fixes the template in the patient's mouth and accurately places the implants on it. Flap surgery is not required: the doctor makes only small punctures in the gum, the diameter of which corresponds to the size of the implants. Thus, the traumatism of the operation is minimized, the gum does not need to be sutured, and there is no risk of inflammation with good oral hygiene. Implantation is performed under local anesthesia. It takes 10 minutes to install one implant. Possible error does not exceed 20 microns.

Clinical case StomArtStudio Leonardo, doctor Vasiliev Leonid Alekseevich

x-ray template

Imaging

Implant planning

Discussion

• template sterility,

• reduction of operation time,
• lower cost.

Today, surgeons and orthopedists have a wide range of different systems and software for 3D implant planning, which allow the use of the obtained data for the automated production of surgical templates. The SICAT planning module is an integral part of Sirona's Galileos digital volume tomography software. Unlike other systems, SICAT is based on pre-imaging templates and is only used for pilot bur insertion. With this module, we can implement a simple, easily standardized workflow.

Currently, three-dimensional X-ray diagnostics is an almost mandatory component of implant treatment. The first system (NewTom, Italy) of digital volumetric tomography (DVT; English name: "conebeam computed tomography", CBCT) began to be used for dental x-ray diagnostics in the late 90s. Since then, DVT, also due to the lower radiation exposure to the patient, has gradually replaced traditional computed tomography in all areas of dentistry. Three-dimensional diagnostics and its visual results in DICOM format have greatly expanded the possibilities of planning. However, certain difficulties arise when combining a virtual picture with an individual clinical situation. In implantology, two methods are used to solve this problem.

The results of 3D diagnostics can be directly used during surgery using the appropriate navigation systems. To do this, the operating space must be limited by a system of fiducial points. In addition, in this space, for example, using infrared markers, it is necessary to localize the tools used. Such systems are successfully used in other areas of surgery (neurosurgery or spinal surgery) and have already been adapted for the purposes of dentistry and implantology.

According to another method, the results of 3D X-ray planning are recorded in the process of automated production of surgical templates (CAD/CAM templates). Such templates, even without 3D planning information recorded in them, have been used for a long time to transfer the planned position of implants into the oral cavity and have proven themselves from the best side. Existing methods for applying such templates, made on the basis of two-dimensional X-ray diagnostics, are not only widely used in practice, but are still being developed and improved.

Existing planning systems and surgical templates based on them can perform various functions and vary considerably in their complexity. All these systems have sufficient accuracy and reliability. The following is our own practical experience with the SICAT planning module. Over the past 12 months, implant planning has been carried out using this system for 72 patients.

Description and technological process

The material basis for the use of SICAT templates is a special set (Starter Kit), which, among many other things, includes bite plates with fiducial markers. Unlike other systems, SICAT is based on templates made before imaging. When planning implantation, first a traditional panoramic x-ray (orthopantomogram) is made and clinical diagnostics are carried out, then casts of the upper and lower jaws are made, and, if necessary, also a recording impression of the occlusion.

x-ray template

For DVT, individual X-ray templates are made, which are a film splint with radiopaque (contain barium sulfate) analogues of teeth in the implantation area and a fixed bite plate. On fig. 1 shows a model of the initial situation with a 1.5 mm thick film tire over Setup. In this clinical case, it is planned to restore the shortened dentition on both sides of the mandible with crowns supported by Camlog implants.

Rice. 1. Model (superhard plaster) of the initial situation with a 1.5 mm thick film splint over the Set-up.

Imaging

When the template is ready, the patient is sent for X-ray diagnostics. After trying on the template, the Galileos spherical head holder is individually adjusted to ensure maximum scanning accuracy. After scanning, a detailed consultation is held with the patient, during which, with the help of the formed visual picture, all the features of the initial situation are explained to him in detail. Thanks to this, the patient gets the most complete picture of the volume and duration of treatment, the need for additional augmentation and possible costs. This is a very important step, since surgical treatment can only be started after obtaining the consent of the patient.

Implant planning

Detailed planning of implantation is carried out in the absence of the patient at the workplace of the Galileos system. The system database contains information about all common implant systems and makes it easy to switch from one type of implant to another and select their length and diameter. We have both a three-dimensional image and layered images at our disposal. It is recommended to work with panoramic and local layered images, since a three-dimensional image does not contain any fundamental additional information.

On fig. 2 shows the results of implantation planning. First, on both sides of the jaw, the location of Canalis mandibularis is indicated. To do this, 6 points are indicated on the left side, and 7 points on the right side, which are connected to each other automatically.

Rice. 2a. panoramic image.

Rice. 2b. Pseudosagittal section of the IV quadrant.

The optimal position of the Camlog ScrewLine implants is then selected using individual layer-by-layer images at optimum magnification. This example illustrates very well the possible problems that arise when implants are placed in the region of the distal posterior teeth of the lower jaw (Fig. 3):

• Tooth area 37. The lingual surface of the lower jaw has a concave shape with a small radius of curvature. Therefore, only an implant with a size of no more than 5.0 x 9 mm can be installed along the optimal axis, and there is a risk of forming an unfavorable ratio between the dimensions of the implant and the abutment. Neither trochlear graft augmentation, nor Bonespreading, nor nerve displacement allow placing a 5.0x11 mm implant in this area and augmenting the vestibular cortical plate with bone chips.
• Tooth area 36. The concavity of the lingual surface is less pronounced here, which allows the placement of a 4.3 x 11 mm implant in this area. However, there is a risk of perforation of the mandible if the preparation is too deep.
• The area of ​​teeth 46 and 47. In the IV quadrant, the anatomy of the lower jaw is less demanding on the size of the implants. In the region of tooth 46, there is a danger of nerve damage if the preparation is too deep, but the 5.0 x 11 mm implant can be placed at a sufficiently safe distance from the nerve. In the region of tooth 47, a 5.0 x 11 mm implant can also be placed.

Rice. 3. A typical report on the results of planning.

When planning implantation, special attention should be paid to choosing the optimal angle of inclination of the implants. The initial vertical position is often inconsistent with the inclination of adjacent teeth and the shape of the occlusal plane. After adapting the angle of inclination of the first implant to the shape of the plane of occlusion, this ratio can be automatically extended to all other implants. A typical report generated after the completion of virtual planning contains all the necessary information to discuss its results with the dentist and dental technician and draw up a treatment plan.

Transferring planning results to a surgical template

The results of the planning are recorded on the Starter Kits CD and sent to the clinic together with the X-ray template on the plaster model (packed in the supplied hygiene bag), the report and the optimal pilot bur diameter. Only 2 out of 72 SICAT cases required additional data. In this case, we are talking about patients with microsurgical transplants after removal of malignant tumors, for which the templates during scanning were not located in the same position as on the model. In all other cases, the results of planning are easily transformed into a surgical template. To do this, remove the bite plate from the X-ray template, cut off the crowns of the teeth in the area of ​​implantation and insert guide sleeves for the pilot bur along the axis of the implants into them.

Discussion

It is possible to use this template only for introducing a pilot drill, which greatly simplifies and reduces the cost of using the system (Fig. 4).

Rice. 4a. Panoramic image after manual marking of the nerve position and virtual placement of two implants.

Rice. 4b. Cross section in the planned position of implants 36 and 37.

Rice. 4c. Fragment of a panoramic x-ray of the situation after the installation of implants.

The cost of such a template without DVT is about 400 Euros, and no special tools are needed during the operation. With successful implantation planning and the correct choice of diameter, length and angle of implants, using a template only for inserting a pilot bur allows you to bring planning results to life with high accuracy. The danger of insufficiently precise insertion of the pilot bur only exists in areas with a thick gingival layer, for example, in the region of the distal maxillary posterior teeth, where the direction of the preparation may differ from the planned one due to the addition of the height of the sleeve and the thickness of the gingiva. A similar problem arises in the region of the second molar in the presence of adjacent teeth, when the introduction of a pilot bur along the planned axis is very difficult. In such cases, we can partially omit the use of a surgical guide and insert a pilot bur without one. Carrying out accurate three-dimensional planning allows you to do this without significantly increasing the risk of any complications. Alternatively, external guide sleeves can be used.

For the successful application of the described technology, it is necessary to know all the fundamental problems of surgical templates, among which Weibrich and Wagner note the following:

• discrepancy between the results of planning and the structure of the bone base,
• the difficulty of fixing the templates in the optimal position after the preparation of the mucoperiosteal flap,
• template sterility,
• contamination of the bur and bone base by particles of the guide sleeve,
• limited accuracy of preoperative planning.

For experienced implantologists, the use of the described technology has a number of advantages:

• reduction of operation time,
• increasing the reliability of planning in relation to the required result and the need for additional augmentation,
• visualization of all necessary measures for the patient,
• ease of practical application,
• lower cost.