Dental implants are artificial replacements for dental roots. Dental implant is usually manufactured from titanium or titanium alloys. The dental implant surface can be covered with different substances to increase its stability and osseointegration. There are several dental implants types, but the contemporary ones have tronconic or cylindrical shapes, the same as the natural dental root. Crowns or dental works (bridges, prosthesis, etc.) are fixed on the dental implants. Dental works on implants can be fixed or detachable (mobile).
Types of dental implants
Root shape dental implants are one of the most popular in the world. They may have cylindrical shapes, smooth or with spires and conical
Dental implant surface
Modern implants have the bone contact surface in rugose topography to allow bone cells to settle on and osseointegrate it, and the one in contact with gums has a smooth, shiny topography, for epithelial gum cells to adhere, sealing the space surrounding the implant’s neck. Technology has enabled the creation of rugose surfaces in several topographies (nano and micro rugosity), so that bone cells can perfectly adhere to the implant. The more rugose surface and carefully processed, the higher the dental implant quality. That because bone adheres much better and more uniform, and present rugosities increase the contact surface between implant and bone, increasing its mechanical stability initially and biological subsequently to osseointegration.
Dental implant components and types of work on implant
Dental implant treatment involves several components: implant itself, prosthetic abutment (connecting implant with the work) and dental crown.
Cemented dental works on implant
Dental implant defines not only the root area (replacement). One of the means through which a crown is attached to the dental implant is by cementing it on an intermediary piece (prosthetic abutment). The prosthetic abutment is screwed to the implant and the work is fixed on it using an adhesive (dental cement). It represents the perfect way to place the crown for a single dental implant and requires great caution because, during the moment of sticking, cement remains/excess can infiltrate under the gum, damaging the implant in time. Sometimes the crown can be cleaned with difficulty and can lose cement or can be lost / broken.
Dental works screwed on implant
The second method for attaching a crown/dental work to the implant is by screwing it. Therefore, crown is directly screwed to the implant and the fixing screw access hole is covered with obturation material (filling) matching the tooth color. The advantage lies in its easy removal anytime when needed (professional hygiene, small fixes, etc.). The disadvantage lies in the fact that this tiny screw can weaken under high pressure, requiring periodic tightening with special keys, wrenches (with a precisely calibrated force couple).
Dental mini-implants are extremely thin implants, with limited resistance and with limited directions:
- Narrow spaces (lateral incisors area) are the narrowest teeth inside the oral cavity – not recommended for the rest of the teeth (they can fracture),
- Mobile dentures stabilization (mobile dentures on „over denture” implants) for the elderly, when mastication forces aren’t that high,
- As temporary implants, for fixing temporary works until definitive implant integration or until bone addition healing when lost bone volume is restored through resorption (melting).
Implants which are no longer used (history)
Although they were “sensational” in their time, these dental implants types are no longer used (blade, subperiostal) or, some of them, are used limited: “bar fixed to the bone” implants and “transosseus” ones – in case of severe bone atrophy, when patient cannot undergo bone addition.
Represented by extremely long implants used in special situations.
Zygomatic implants are placed in the back of the maxillary bone (superior), where maxillary sinuses reside and bone has the lowest density. The tips of these implants are anchored into the zygomatic bones (cheekbones), which maintain volume and density throughout time, even if the maxillary bone is resorbed. These implants are recommended for severe maxillary atrophies, when there is practically no bone left (in the superior maxillary) or remaining bone is in an extremely low quantity, being filled with air by exaggerated sinus volume enlargement. In this case it represents a good alternative to invasive surgery, when patient is unable or unwilling to undertake complex bone additions for lost bone volume enlargement in this region. Zygomatic implants rapidly and efficiently ensure an excellent stability in the posterior area for immediate dental works (allows immediate anchoring to fixed works).
In certain techniques, conventional implants can be successfully combined – in the frontal region we insert conventional implants and in the posterior areas we insert zygomatic implants – procedure called „TotalFix+”.
For severe maxillary atrophy conditions in all areas (including anterior) a number of two or three zygomatic implants are inserted individually yet simultaneously, in the same session, on each side of the superior maxillary (four or six in total), techniques called „QuadZygoma” respectively „Sixzygoma”.
Zygomatic implant insertion is carried out through extremely complex surgical procedures that involve an experienced medical team (implantologists, oral and maxillofacial surgeons, prosthetists, anesthetist, etc.) and all equipment specific for a major surgical act – operating block, general anesthesia, dental CT scanner, etc.