The zygomatic implants are the perfect implants in cases where the patient has a lack of bone and does not want to perform any type of grafts or sinus elevations since their size is smaller and occupies the necessary space with the bone that the patient has.
Conventionally, if a patient has a lack of maxillary bone, a sinus lift or bone graft is always performed prior to the placement of dental implants, but with these zygomatic implants we can avoid this previous treatment.
Advantages of zygomatic implants:
- High success rate and with low probability of complications
- Better alternative to bone regeneration treatments (bone grafts or sinus lifts).
Pathologies to consider before performing zygomatic implant surgery
- Arterial hypertension (AHT): anesthetic procedure with vasoconstrictor in hypertensive patients are recommended not to use more than 2 carpules with epinephrine at 1:100,0008,.
- Ischemic heart disease: perform surgical treatments after 4 to 6 weeks have elapsed.
- Anti-aggregants: anticoagulants: the patient must be monitored with NRI.
- Bacterial endocarditis: give antibiotic prophylaxis.
- Intravenous bisphosphonates, it is necessary to wait 6 months due to the risk of osteonecrosis. Osteoradionecrosis can also occur as a consequence of radiation in patients who are being treated with radiotherapy in head and neck regions.
Other pathologies to take into account are:
- Uncontrolled diabetes: hyperglycemia reduces osseointegration (can lead to infections)
- Uncontrolled hepatopathies: deficit of hemostasis leads to an increased risk of bleeding.
The 4 techniques for the placement of zygomatic implants
The first step for any type of surgery will place local anesthesia in order that the patient does not feel any discomfort during the intervention, also in nervous and anxious patients we have the option to place in addition to local anesthesia, working under the effects of conscious sedation.
Classic Branemark technique
It is placed through the maxillary sinus until it reaches the zygomatic arch.
A 10 mm wide window is created in the maxillary bone height and the Schneider’s membrane is removed by detaching it from the sinus walls in order to perform the drilling sequence.
Finally, the zygomatic implant made of titanium is placed, then a healing cap is placed and the flap is sutured.
Sinus Slot Technique (Stella and Warner)
This technique allows placing the zygomatic implants in a more axial position which makes the head of the implant go towards the vestibular (better rehabilitation with the prosthesis) thanks to the opening of a window in the lateral part of the maxillary sinus in order to accurately position the implant without the need to access the high window of the maxillary sinus (Branemark technique).
Exteriorized or extrasinusal technique with zygomatic implants
This technique is perfect for patients with very pronounced concavities.
The externalized technique reduces the palatal position of the implant.
At the time of the treatment, there is a better vision of the operative field and a better position when placing the implant and its rehabilitation with the dental prosthesis.
The placement of the zygomatic implants will be external to the maxillary bone and anchored only in the malar, so most of the implant will be outside the bone and covered by soft tissue, which will also increase the length of the malar bone perforation and in turn expand the bone-implant contact surface, thus creating greater primary stability.
Zaga Technique: The Zygoma Anatomy-Guided Approach
This technique consists of an individualized surgery, that is, a technique adapted to the anatomy of each patient, thanks to which a better design of the prosthesis is achieved (less bulky and more hygienic), as well as reducing the possibility of late sinus complications.
The ZAGA technique reduces the distance from the center of the implant head to the center of the prosthesis.
This type of technique will be chosen taking into account the concavity formed by:
- Alveolar ridge
- Maxillary sinus
- Region of zygomatic bone receiving the implant
When the upper jaw is very resorbed, this concavity is small, so the classic technique could be used.
When the resorption generates a large concavity, the externalized technique should be used, otherwise the intrasinusal technique can be used, with several intermediate stages between the two.
Guided surgery with zygomatic implants
Another new technique is guided surgery, which uses surgical splints in order to have greater precision when drilling and placing the implants without the need for a flap, but it is always recommended to have a direct view of the bone to avoid placing the implants near the orbit or even perforate it, combining the use of surgical splints with the “sinus slot technique”.
On the other hand, there is the computer-guided surgical navigation technique, thanks to which we will achieve greater precision of the drilling, controlling the direction of the implant and checking the fidelity of the surgical guide with respect to the anatomical structures.
