Dental implantation

Modern dentistry has made significant strides in the development of bone-integrated dental implantation. In addition to the placement of a single artificial tooth, there is now the possibility to replace several missing units simultaneously using bridge prostheses supported by implants. The installation of such orthopedic devices involves numerous nuances, advantages, and disadvantages. All of these must be considered before undertaking this multi-step procedure.

The placement of dental implants has been practiced by dentists for several decades. What are dental implants? Practically everyone is familiar with this technology to some extent. In very simplified terms: a titanium screw is inserted into the bone, integrates with it; an abutment is placed on the artificial root, and then a ceramic crown is attached on top.

The most crucial aspect of implantation is the quality of the artificial root's integration. Leading global manufacturers guarantee the integration success of their products up to 96-99%. In the vast majority of cases, prostheses are made from a titanium alloy, which is highly compatible with human tissues and does not cause allergic reactions.

Advantages of Dental Implants

Modern implantation offers numerous advantages. The most important is that it restores a complete dental arch. The patient not only achieves healthy oral function and can handle normal masticatory loads but also gains an unparalleled aesthetic effect. Artificial teeth look exactly like new ones, only much stronger.

Dentists also note a number of additional advantages of dental prosthetics:

• The presence of a prosthesis prevents bone resorption. Without constant load, the bone loses its function and begins to atrophy gradually.
• Modern technologies allow the artificial root to be implanted immediately after the problematic tooth is removed. This "same-day methodology" saves the patient's time and nerves.
• Artificial teeth are neither visually nor in their qualitative indicators inferior to healthy natural teeth.
• Two implanted implants can serve as a base for a bridge prosthesis, which replaces several lost units at once.

Indications for Dental Implantation

Dental prosthetics are suitable for the vast majority of patients. There are contraindications, but some of them are relative and may disappear over time. There are many indications; dental tooth implantation is recommended for any patient approximately from the age of 20, with virtually no upper age limit (more so, it is determined by the patient's health rather than their age).

Let's list the main indications:

• Missing a single tooth, while the neighboring teeth are fully or relatively healthy.
• Missing three or more teeth.
• Allergy to plastic components in prostheses;

Contraindications for Dental Implantation

All restrictions can be conditionally divided into two groups. Absolute contraindications imply that prosthetics are impossible in this case in principle:

• Any infectious diseases in the acute or chronic phase.
• Any bone tissue diseases.
• Any blood system diseases.
• Any tumors of the bones or soft tissues of the oral cavity.
• Growth of teeth and skull bones in progress (usually completed by age 20).
• Mental illnesses, risk of relapses. The process of dental implantation is often prolonged and requires a high level of discipline from the patient.
• Drug addiction, alcoholism. The body (and tissues) of such a patient are weakened. Additionally, as mentioned above, a patient with such conditions is unlikely to strictly follow all the implantologist's instructions during the procedure.

The list of relative contraindications is also quite substantial. The only difference is that relative restrictions may disappear over time. Then, after consulting with a doctor, the patient can begin the dental implantation protocol. 

So, what are these temporary contraindications:

• Age below 20 years. If an artificial root is implanted in the jaw before this age, it may interfere with the natural growth of the jawbone. Moreover, until the jaw is fully formed, there may simply not be enough bone volume for quality dental implantation.
• Poor condition of the oral cavity surfaces. Before starting implantation, the dentist must thoroughly clean the tooth enamel of plaque and tartar. Any defects on the mucous membrane of the gums, cheeks, tongue, or palate must be treated beforehand.
• Diseases of the immune or hematopoietic system.
• Excessive smoking (15 or more cigarettes per day). Until the patient reduces the intensity of smoking, the doctor cannot allow them to undergo such a complex procedure as dental implantation. Ideally – completely quit smoking, not only during the implantation and rehabilitation period but permanently.
• Bruxism (teeth grinding during sleep). It is desirable to minimize such manifestations or protect the teeth from them mechanically. Special plastic caps can help with this.
• Long-term use of medications such as antibiotics, antidepressants, anticoagulants. All of them significantly affect the patient's body, which will hinder the quality integration of the implant. However, after finishing their use, implantation can be planned.
• Hormonal instability (during menopause). During this period, bones can become brittle. For the same reason, dental implantation is impossible during pregnancy and breastfeeding.
• Too small bone volume (after long absence of a tooth, part of the tissue atrophies). About twenty years ago, this would have been a serious obstacle for dental implantation. But technologies are advancing: today, it is possible to increase the missing bone volume.
• Periodontal disease. In this condition, the gums do not tightly embrace the tooth (native or artificial). After implantation, bacteria and food particles can enter the "pocket," making tissue inflammation unavoidable. In such a defect, implantation must be preceded either by a course of gum tissue treatment or its augmentation.

Types of Dental Implants

Today, the dental implant market offers a wide variety of options for any situation: intraosseous, extraosseous, long, short, smooth, textured, with immediate or delayed loading. Even for the most seemingly hopeless situations, a doctor can now select a suitable option. Let’s consider the main classifications. Non-removable implants are divided into intraosseous and extraosseous.

Intraosseous Implants

The name speaks for itself – the stabilizing part of the prosthesis is implanted into the bone. It can either mimic the shape of a tooth or look completely different. Mimicking the natural root shape increases the chances of successful integration and provides a more even distribution of masticatory load in the jaw.

• Plate implants are characterized by their usually textured or corrugated surface. The macrotexture on the root may resemble a snake. Such irregularities serve to ensure that the human tissue fuses with the prosthesis, providing maximum adhesion.
• Root-shaped (endosseous) implants. They, in turn, are divided into subtypes. For example, cylindrical implants have a smooth intraosseous part. Screw implants can be detachable or non-detachable. The product's coating can be either smooth or rough. Basal implants have an elongated shape and threading.
• Mini-implants can also be classified as root-shaped. They are usually temporary options. Due to their lightweight construction, they are suitable for patients with osteogenesis disorders. They are equipped with various anti-rotational locks and holes, preventing the implants from shifting or rotating around their axis.
• Combined variants are composite: the central part is cylindrical, and the "side" roots consist of two additional plates.

Extraosseous Implants

Such options may be suitable for elderly patients who have problems with bone density.

• Subperiosteal implants are usually used to treat patients with a high degree of jawbone tissue atrophy. The prosthesis has an arch shape and is usually placed along the entire length of the dental arch. The doctor screws it into the periosteum under the mucous membrane. An artificial row of teeth is later snapped onto this base.
• Intrasulcal implants are used when there is an insufficient amount of the patient's own bone tissue. They appear quite simple: miniature mushroom-shaped magnets are implanted under the mucous membrane. Removable orthodontic prostheses are then attached to them.
• Stabilization implants are mounted on the patient's natural tooth root. However, this is a temporary measure, as any natural bone tissue loses its density with age and may crumble.

Stages of Dental Implantation

1. Examination

Implant placement is a lengthy, complex process that requires thorough preparation. The more nuances the doctor accounts for during preparation, the more seamlessly the prosthesis will fit, and the higher its chances of successful integration.

Preliminary examination is a multi-step process; let's list the main stages:

• X-rays and other images. Based on these, the doctor will determine projection distortions.
• Osteometer examination. It calculates the parameters of the alveolar ridge. This data helps select a dental implant of the required diameter.
• Creating a plaster model of the jaw with a full set of teeth. Usually, it is made considering the intermaxillary interaction. A plastic template is then made based on this model.
• CT scan. It also provides the doctor with important details about the condition of the jaw in all its intricacies, indicating the vascular-nervous bundle. Since teeth, bones, and soft tissues have different densities, the program can visualize all structures in detail.
• Selecting the implant and its placement site. First and foremost, the quality and other parameters of the bone tissue at the proposed installation site are considered, with an eye on future masticatory load.
• Prototyping the jaw. At this stage, the relationship between the future implants and the antagonist teeth is checked.
• Prototyping the surgical template. If the implant location is strictly limited, it is placed at the required angle. A special template with titanium cylinders is prepared for drilling precisely at the specific location and angle.

2. Surgical Stage

The actual installation of the prosthesis is no less important. Since the procedure is invasive, it is always performed under local anesthesia. During the operation, pressure is applied to the nerve endings, and blood is absorbed into the spongy bone structure—all of which cause pain.

By the way, moderate bleeding during prosthesis implantation is necessary—to allow blood to fill the voids between the bone and the implant, preventing the formation of air pockets. This will facilitate the quality integration of the prosthesis.

At the very beginning of the operation, once the anesthesia has taken effect, the doctor makes incisions and retracts the mucoperiosteal flaps. The incision is made along the middle of the alveolar ridge crest. This way, the doctor avoids any vertical cuts that leave scars after healing.

The localization and angle of the artificial root depend on the deficiencies in the dental arch and the characteristics of the patient's jaw. If the alveolar bone is relatively preserved, the implantologist follows several rules during prosthesis installation.

• A minimum of two to three millimeters should be between implants. Otherwise, the bone may remodel and atrophy.
• Roots are usually placed at an angle to each other—this allows for a better distribution of the load.

The implant itself is soaked in saline before being inserted into the bone to minimize friction. In single-stage implantation, a gum former is placed immediately. This is a temporary element of the dental implant that shapes the natural contour of the gum tissue. During two-stage implantation, the doctor places an abutment screw.

3. Orthopedic Stage

Over time, the gum former is replaced with a supporting abutment. Shortly afterward, the installation of a special orthopedic structure is possible. An impression is made from the molding mass, and then the prosthesis itself is fabricated. This is the work of an orthodontist. The timelines and procedures are similar to those used in the regular fabrication of a crown.

4. Postoperative Stage

Approximately one and a half weeks after the artificial root implantation, the doctor removes the stitches. During this time, the patient is advised to rinse their mouth with chlorhexidine. Another week later, they can start trying to wear removable prostheses.

If transocclusal screws were used during implantation, they may need to be tightened slightly. In any case, the patient should visit the dentist for a check-up about one and a half months after implantation, and then again in three to five months.

Types of Implantation

Implants are classified by their types, installation methods, and interaction with bone and soft tissues.

There are quite a few options for various complex cases:

• Endosseous implantation. Today, this is the most sought-after type. The intraosseous element resembles a screw, plate, or cylinder. This type is widely used in restoring an entire row of teeth—with three, four, or six prostheses.
• Endodontic-endosseous. In this method, the doctor uses a post and other fixation elements in the bone. They are usually placed in the root canal. To perform such an operation, the doctor must have special skills.
• Subperiosteal (under-the-bone membrane). More often used in cases of pronounced degeneration of the alveolar ridge. First, an impression is made on the bone, and then the implant, which is placed under the periosteal layer, is fabricated based on this impression.
• Intrasulcular. The doctor places the implant in the mucosa on the alveolar ridges. There is no need to drill the bone. The implant itself is small in size and resembles a button.
• Submucosal (submucosal). This type of implantation is considered one of the easiest, safest, and least invasive. Powerful magnets are placed in the subperiosteal shell, which securely fix and stabilize removable prostheses.
• Transosseous. The system is implanted under the gum with anchoring to the bone.

Implantation Techniques

Surgical implantation techniques are divided into two-stage and single-stage. The first is classical (older), takes more time; the second allows the tooth to be loaded shortly after implantation.

• Two-stage. In the first stage, the root is implanted into the jawbone. For this, the gum is cut, and flaps are retracted. Then, with a drill (diameter 2-2.5 mm), an axial channel is bored into the bone and slightly expanded.
  If the root part of the implant is screw-shaped, the doctor manually cuts threads into the bone using a special tool. Only then is the root screwed in.
  If the implant has a cylindrical shape, a bed is formed for it in the bone using a special milling cutter. After screwing in the root, it is covered with a cap, left for osseointegration, and the gum flaps are sutured.
  The second stage occurs after two to three months. When the root has successfully integrated, the doctor re-cuts the gum, removes the cap, treats the channel, and places the crown. If necessary, the cuts on the gum are sutured.
• Single-stage implantation (same-day, express implantation). During this procedure, the doctor also cuts the mucosal tissue and prepares the bone bed with instruments. Then, the prosthesis and artificial crown are installed. It is worth noting that not every clinic is equipped with the necessary equipment for this type of implantation. Moreover, not every doctor has the corresponding qualifications. In our "Dental Guru" clinics, we have all the necessary equipment, experienced specialists, and implants that are used exclusively for such single-stage placements (for example, "Impro Respect" and "Impro Implantem").

How Prostheses Are Attached

It depends on whether the prosthesis is removable or not. Permanent non-removable prostheses are installed by an orthodontic surgeon. Either using dental cement or locking mechanisms.

• A crown is glued directly to the top of the implant using cement. The teeth look very natural. This is a fairly quick and inexpensive—hence a popular attachment method. However, it has its drawbacks. For example, if cavities remain between the gum and the prosthesis during cement fixation, there is a risk of inflammation. It is difficult to thoroughly remove excess cement during installation. If the implant needs to be extracted, its parts may be damaged or chipped off.
• With locks (attachments), the prosthesis attaches quite well to the implants. Locks can have different shapes and are located on the outer side of the crown or inside.
• Screw fixation is one option for removable implants. The device can be attached either to the intraosseous part of the implant or to the abutment. Advantages: if the abutment is damaged, the prosthesis can simply be disassembled and replaced. Disadvantages: access holes need to be filled with fillings; the root inside the bone requires more space.
• Button attachment. Usually, two points in the form of balls or couplings are sufficient for fixation.
• Magnetic fixation. They are soldered to the prosthesis abutment. Dentists note that the prosthesis holds well when the patient opens and closes their mouth, but during chewing or food grinding, the prosthesis may shift.
• Telescope attachment. A prosthesis with cylinder or cone-shaped holes is placed on four implants. This construction is sufficiently massive but does not cause complications on the mucosa.
• Bar attachment. The structure connects two to four implants, preventing them from loosening. As a result, the prosthesis is firmly fixed.

Each detail of the implantation is individually selected by doctors for each specific patient after thorough examination, taking into account all restrictions. Today, specialists can model the implantation process using computer programs. The patient usually does not participate in making key decisions—there are many medical nuances, but they can, for example, choose the crown material.

In any case, the more professional and experienced the team of specialists is in prosthetics, the higher the chances of success. Modern implantology offers a wide range of opportunities to achieve a beautiful smile.