OPTIMIZATION METHODS FOR THE

APPROACH TO

IMPLANT INSTALLATION TECHNIQUE

V. G. Klimentyev
European Dental Center, Kiev, Ukraine
Summary. In this paper, we propose methods to optimize the approach to the method of implant placement in the tubercle-winged suture, which improve the planning processes before implant placement, as well as accelerate the process of osseointegration.
Key words: tubercular-pterygoid suture, plasma enriched with growth factors, computed tomography.
Despite its rigidity, bone is a system that is subject to shape change, restructuring, and repair processes. In addition, osteoblasts, osteocytes and osteoclasts are constantly involved in a coordinated activity that maintains safety, updates and restores the intercellular matrix of the bone. This group of cells responsible for bone regeneration is known as the basic restructuring unit. The skeleton of an adult contains about 35 million of such restructuring units, while 3-4 million of these units are activated every year — this gives a vision of the intensity of cellular activity. Very often, patients who have atrophy of bone tissue and who need help go to dental clinics.
   
About 80% of the skeleton consists of cortical bone and 20% of the trabecular bone. When considering bone metabolism, you can notice the difference; despite the fact that the trabecular bone as a component in the minority, the most intense metabolism occurs here, eight times more intense than in the cortical. This fact explains that the surface area and cellular composition of the cortical bone are much larger. Cortical bone predominates in the appendicular skeleton; its presence is typical for diaphysis of long bones and peripheral parts of short and wide bones; It withstands bends, turns and distributes forces. The axial skeleton is larger than the trabecular, or trabecular bone; it forms the central parts of short and narrow bones and is designed to withstand pressure and the action of compression forces. Long bones, for example, contain cylindrical parts, or diaphysis, consisting of cortical bone; at the ends of the bone, the diaphysis expands and passes into the area of ​​the trabecular bone, called the pineal gland, which is the part that articulates with other bones. On the pineal glands, a tubular bone covers a thin layer of the cortical membrane to distribute the mechanical load of the joints, however, the trabecular bone absorbs the dynamic load.
Dental implants in the early stages of atrophy can suspend the process of bone resorption, but, as a rule, patients seek help even when the atrophy of the alveolar process has reached a significant size. The use of surgical techniques such as augmentation significantly increases the duration of treatment for this disease. Based on this situation, patients make their choice in favor of removable dentures. In this situation, you can offer an alternative solution to the problem, which will be less invasive and more effective. In such cases, we can talk about installing implants in the tubercle-pterygoid suture of the upper jaw and additional techniques that make this procedure effective and safe.
Even with the most advanced cases of atrophy, the tubercle of the upper jaw always preserves a section of unresorbed bone tissue. Anatomically, the tuberoid-pterygoid suture connects the pterygoid processes of the main bone with the upper jaw. The attachment of chewing muscles makes it possible to preserve and maintain bone tissue in this area. The installation of implants in this area allows you to achieve maximum primary stability due to direct fixation in the hard cortical bone.
The installation of implants in the tubercle-pterygoid suture makes it possible not to carry out a sinus lift operation, while minimizing the risk of surgical injury. When planning the operation, we used an additional diagnostic method — computed tomography, and during the operation — blood plasma enriched with growth factors, as an autotransplant material.
Computed tomography is a more professional and modern type of jaw examination, which, as a rule, refers to additionally prescribed studies in cases when a conventional panoramic image is not enough.
Computed tomography of the jaw is a layered three-dimensional image that allows you to evaluate the anatomical features of the structure of the teeth, roots and root canals, and most importantly — accurately determine the volume of bone tissue necessary for implant placement, simulate the position of the implant in the bone structure, and also calculate its exact location and direction in the jaw.
The implantologist immediately has several significant advantages:
• diagnostic accuracy — computed tomography allows you to get an unlimited number of slices to calculate the thickness and height of bone tissue necessary for installation and fixation of the implant;
• guarantee of the result — a three-dimensional model of the jaw several times increases the information content of the study, so that the doctor gets the opportunity to build a treatment plan in the most effective way.
Computed tomography also involves modeling the phased process of installing the implant on a computer and gives the patient the opportunity to evaluate the intended result before the operation begins.
The process of tissue repair is based on a complex sequence of biological phenomena that are controlled by a long list of biologically active growth factors and proteins. The spatial and temporal effects of this family of mediators in the area of ​​damaged tissue regulate the mechanisms and phases that control tissue repair and regeneration. For example, in the case of bone regeneration, the goal of the initial development of local growth factors is to stimulate the flow of osteoprogenator cells to the site of injury and subsequently direct them in a certain way to differentiate towards osteogenesis. Throughout this process, a number of other factors will regulate the dynamic equilibrium of intercellular inhibition and proliferation, as well as angiogenesis and the formation of intercellular matrix.
This means that functional tissue repair depends on a number of stages or phases, which are controlled by a large number of biological mediators, which, in turn, appear and act in time and space. This is definitely the duality of the growth factors that are responsible for the final analysis of the correct development of tissue, and that is why there was a desire to better understand this phenomenon. A detailed study of tissue repair processes has led to the discovery of the importance and fundamental role of platelets in this context. Platelets can serve as a physiological reservoir of growth factors and proteins, that is, functional units whose potential interest is in their biological mediator composition. The technology for producing plasma enriched in human growth factors is based on a thorough study, use, preparation and activation of an autogenous enriched platelet mass, which, among other things, is characterized by its biocompatibility and accessibility.
A detailed study of the characteristic properties of platelets along with optimized conditions for their concentration, activation and released energy made it possible to develop a technology with great adaptability and therapeutic potential. Plasma enriched with human growth factors is a one hundred percent autogenous platelet product that has unique properties that make it optimized for the manifestation of biological effectiveness and biosafety.
Tissue regeneration includes a complex series of biological processes that are controlled by the interaction of a mixture of growth factors. There are three factors involved in tissue regeneration: the cellular component, a combination of various biological mediators, which include growth factors, including cytokines, and the matrix, or “framework”, which provides structural support for new tissue.
After injury or tissue damage, they are activated and coordinate many intercellular or intracellular pathways in order to restore the structural integrity of the tissue and its hemostasis. Growth factors are also necessary to stimulate angiogenesis, or the formation of blood vessels, which will supply oxygen and nutrients to the tissue damage area. Another fundamental aspect to consider from the perspective of tissue regeneration is the formation of a “framework”, which acts as a temporary intercellular matrix and, accordingly, arranges the cells in such a way that they reproduce their biochemical, physical and structural impulses, which ensures fixation of the mechanisms of cell motility.
It is these positive properties of the plasma enriched with growth factors that can be used when installing implants in the tubercle-winged suture to improve and accelerate the processes of osseointegration.
The operations took place under local anesthesia. All the rules and regulations of the protocol for installing one-stage implants were observed. Suture guidelines were determined by clinical parameters after examination and palpation, as well as after preliminary computed tomography. When choosing an implant placement site, it is necessary to draw two conditional lines: line “A” — a conditional perpendicular straight line drawn from the projection of a large palatine opening to the intersection with line “B”; line “B” — a conditional line connecting gamulus lamina pterygoidea interna os sphenoidale to the base zygomatic alveolar ridge.
    This point is the implant placement site. Drilling and placement of the implant must be done strictly up and back from the tuber of the upper jaw. The use of a flapless technique practically did not violate tissue trophism; regeneration processes were completed in a short time due to the use of the above plasma enriched with human growth factors.
Clinical case No. 1
Patient M. went to the clinic complaining of a partial absence of teeth on the upper and lower jaws. After a CT study, significant atrophy of the alveolar process of the upper jaw was detected (Fig. 1).
Figure 1. Panoramic picture of patient M. before surgery.

It was decided to install one-stage implants in the tubercle-winged suture for subsequent fixation of the fixed structure. Before installation, the implants were treated with plasma enriched with human growth factors to improve osseointegration processes (Fig. 2, 3, 4).
Fig. 2. Blood sampling from patient M.
 
Fig. 3. Obtaining plasma enriched in human growth factors.
 
Fig. 4. Treatment of implants with plasma enriched with human growth factors.
 
After tooth extraction, hole curettage was performed using an erbium laser.
Before implant placement, bone canal irrigation was performed with 10% povidone-iodine solution.
Figure 5. Postoperative panoramic radiography of patient M.
 
After 6 months, the next stage was performed — permanent prosthetics.
Figure 6. The condition of the oral cavity before prosthetics.
 
Figure 7. Fabrication of a ceramic-metal bridge to the upper jaw.
 
Figure 8. Fabrication of a ceramic-metal bridge to the lower jaw.
 
Figure 9. Panoramic picture of patient M. 6 months after surgery.
 
Figure 10. Photograph of established permanent ceramic-metal bridges. 6 months after surgery.
 
CONCLUSIONS
The use of sinus lift can be justified from the point of view of creating artificial additional bone volume in the lateral part of the upper jaw, but even with such indications, sinus lift is evaluated negatively, primarily by patients, due to invasiveness, the risk of transplant infection, and also the duration of treatment. The implant placement technique without sinus lift is much safer and more effective than the combined sinus lift technique and two-stage implantation.
Surgical risk during interventions in the tubero-palatine-pterygoid region is associated with the presence of vessels passing here (descending palatine artery and venous plexus). The analysis of the data performed on a cone beam tomograph is the goal of finding the possibility of installing dental implants to bypass important anatomical formations on the upper and lower jaws with bone deficiency at the planning stage.
It is generally recognized that the redistribution of occlusal forces should go to opposite cortical plates. This is precisely what led to the development and improvement of the implant placement technique in the tubercle-pterygoid region. A one-stage implant fixed in a dense bone of a tuberous-pterygoid suture can be loaded with a temporary prosthesis after two to three weeks. When using implants in the tubercle-pterygoid region, as well as additional methods for using plasma enriched with human growth factors, the process of complete rehabilitation of the patient is reduced by many months.
The bone density in the site of the tubercle-pterygoid suture is significantly higher than that of the alveolar bone.
The use of long implants in the lateral parts of the upper jaw with a minimum height of the alveolar ridge fixed in the tubercle-pterygoid suture, as well as the use of CT diagnostics in the planning of surgical intervention, avoid additional trauma during bone augmentation, as well as significantly reduce treatment time due to the use of plasma enriched with human growth factors.
 

---

28.11.2019