Zygomatic Implant Systems - A Complete Guide & Critical Review for Surgeons and Prosthodontics
A perfect zygomatic implant system will bring terrible results in untrained hands. A not so good zygomatic implant system can provide excellent results if handled correctly.
However, let's imagine the ideal situation. It would be the sum of a highly trained surgeon using a state-of-the-art zygomatic implant system. But what should an ideal zygomatic implant system be?
It is kind of question that the beginner cannot properly answer. It is necessary to experience some situations to understand what differentiates a sound system from a system that leaves something missing.
The ideal zygomatic implant system allows the surgeon to achieve his goal during the surgery, providing ideal solutions for each clinical situation, with good mechanical and biological performance. It must promote biological longevity and optimal prosthetic outcome.
Several companies worldwide manufacture and sell zygomatic implants. Given so many options and possibilities, what is the best zygomatic implant system in the world?
Beforehand, I can say that there is still not what we could call the "perfect" zygomatic implant system.
However, some systems have certain advantages over others, which is exactly what we will cover in this post.
Zygomatic implant surgery is an advanced implant dentistry technique. The surgeon must be entirely focused on the surgical technique and install the implant in the ideal position from an anatomical and prosthetic perspective. An inadequate zygomatic implant system can bring complications both immediately, in the trans-surgical period, as well as in the late postoperative period.
So you have several ways to get this information. One way is to test various systems yourself and draw your conclusions until you find a system that meets your needs.
Another option is to read this post to the end.
Understand that what I wrote in the sequence represents my point of view, but we certainly have here how to listen to the experiences of countless other experts in zygomatic implantation around the world.
Many opinions will have a commercial bias since many experts are linked to implant systems companies; however, our critical census and scientific debate will always prevail.
Let us get to the point. What is the best zygomatic implant system?
Complex questions require complex answers, and maybe this post will be a little long, but it will undoubtedly open your mind to what matters.
To better guide our choice, we will first define the selection criteria: the ideal characteristics that a zygomatic implant system should present to best solve our clinical needs.
1) Zygomatic Implant Lengths
In the case of conventional dental implants, this is not usually a big issue. However, in the case of zygomatic implants, there are essential differences between the various implant systems.
In practice, when installing four zygomatic implants, the anterior implants will always be larger than the posterior implants, for anatomical reasons.
It may seem like a minor detail, and it may even be in some cases, especially when it comes to hybrid Allon4, but when we are facing Allon4 Zygoma (Quad-Zygoma), the lengths of the implants can become something decisive for the resolution of some cases in an ideal way.
The sizes of the zygomatic implants to be used in each case do not depend only on each patient's anatomy but also on the implants' three-dimensional positioning.
The BIC (bone-to-implant contact) varies between patients, but it can also vary in the same patient, depending on the position in which the implant is installed.
It is currently possible to determine the zygomatic implant's maximum anchorage area in the zygoma body with virtual planning. From there, position the implant's head in the most favorable position concerning the residual ridge and screw prosthetic emergence. Also, there is the possibility of more advanced adjustment, a fine adjustment of the three-dimensional position in the implant in the zygomatic bone.
In 3D virtual planning, it is possible to plan, under an axial view, about the distance between the osteotomy/implant and the zygomatic bone's internal and external cortical. It can be a crucial factor in stabilizing zygomatic implants and preventing even a possible fracture of the zygomatic bone's outer cortical. With this degree of planning, the use of "longer than usual" implants is very common in cases of quad zygomatic implants (quad zygoma).
As much as such concepts may seem to be just a personal preference, the scientific literature supports such clinical perceptions (we will see later).
What about zygomatic implant companies? Are they placing implants in their production line that meet all the surgeon's clinical needs in this regard?
Some companies stand out in this regard, such as SIN Implant System, which has zygomatic implants with lengths up to 62.5mm. At the other extremes, we have implant systems that are highly regarded over time, such as Nobel Biocare, but which have maximum implant lengths of 52.5mm.
I have compiled the lengths of the main companies' zygomatic implants that produce and market this type of implant in the table below.
Note that the minimum length of zygomatic implants varies between 30 to 35mm (variation of 5mm). On the other hand, the maximum length varies between 52.5 to 62.5mm (variation of 10mm). Why is there so much variation, especially when it comes to maximum length? What is the clinical relevance of it?
It seems like a simple answer, but it is not, and to not make this post even longer, I wrote a specific post about zygomatic implant lengths.
We can conclude this subtopic with the following assumption:
the ideal zygomatic implant system must cover a wide range of implant lengths to have the ideal solution for each clinical situation.
See more about zygomatic implant length here in this post
2) Zygomatic Implants Design & Surface
For the general design of zygomatic implants, some points are critical and others desirable. For didactic purposes, we will separate by areas of the zygomatic implant.
The apex of the zygomatic implants.
The apex is the part of the zygomatic implant where most of the zygomatic implant insertion will take place in the bone. In some situations, there is a residual bone in the region of the maxillary ridge, but it is in the region of the zygoma body that the largest area of osseointegration will occur.
As zygomatic implant surgery aims to promote immediate loading, many surgeons can immediately imagine an apex with aggressive thread design to promote optimal primary stability. Therefore, the immediate loading could be done without fear of micro-movements during the masticatory function.
When installing a zygomatic implant, we must always keep in mind that the type of bone we will find during the osteotomy is a bone with a strong tendency to be corticalized. For those who have never had zygomatic implant surgery, we can make an analogy to tactile perceptions when milling an anterior region of the mandible. Most of the time, we will find a bone of excellent quality. Little corticalized bone in the mandible's anterior region can also be found, but this is the exception.
If you go for mandibular protocol surgery, would you choose which dental implant design beforehand? Would you do an underpreparation and use an implant that promotes significant bone expansion? Not. The insertion torque would increase so much that it could even damage the implant connection (as for the biological part, we will address the torque issue in this other post).
Keep in mind that we have a significant difference in the mandible surgery concerning the zygomatic implant. In mandible, the implant's apex is completely intraosseous (unless you bicorticalize the chin and install it beyond the mandible basal bone). Such a situation is unlikely in lower jaw surgery, but in zygomatic implants, it does happen in the zygomatic bone.
During an osteotomy, we externalized the drill tip through the outer cortical of the zygomatic bone. After measurement of it, a zygomatic implant is selected. Sometimes, the implant may be installed, and the implant's apex may slightly exceed the limit of the zygoma's outer cortical. It is not a desirable and intensive maneuver, but it can happen.
I had a case of a short face patient in which I selected the smallest zygomatic implant available by the company - 32.5mm - and even so, the implant's apex was slightly prominent on the outer region of the zygoma body.
It's here where we need to pay attention to the detail of an ideal apex for zygomatic implant.
It needs to promote a good insertion torque, but it needs to be designed for corticalized bone. It means that we need less aggressive threads. It is not uncommon for zygomatic implant surgery to have excess installation torque. If the surgeon insists on attempting to continue installing the implant with much higher than typical torques, there may be mechanical problems in the implant assembler, such as a broken screw or even fracture of the zygomatic bone. I have experienced all these situations a few times, and I can assure you that this is not a pleasant surprise.
I've 'discussed these topics specifically in other posts - installation torque - fracture of the screw - fracture of the zygoma during the installation of a zygomatic implant.
When we evaluate some zygomatic implants' apexes on the market, it is clear that many of them present excessively aggressive threads.
Some of them have threads shape designed for soft bone, which is not suitable for the dense bone.
It can make the implant installation a little difficulty in type I or II bone. See some examples below and draw your conclusions.
Other zygomatic implant companies opt for an apex optimized for locking; however, the apex's end portion remains sharp. If an insertion occurs beyond the limit of the zygoma body's external cortical, this apex may be more noticeable on cutaneous palpation.
See below the similarity between the NobelSpeed implant's apex concerning to the Nobel zygomatic implants' apex shape. NobelSpeed was design for osseoexpansion and underpreparation. Is it the clinical reality that we find in most cases of zygomatic implants?
Finally, there are zygomatic implants whose threads are not as aggressive, and the final apex is rounded. I have been using a zygomatic implant model with a rounded apex and soft threads for more than 10 years. I can guarantee that locking these implants was never a problem.
2) Cervical Region
Most companies have focused a lot of attention and study on the cervical region of conventional implants. We can say that this is possibly the most discussed millimeter in implantology worldwide.
The type of connection, platform, design, and surface treatment are some variations studied to optimize osseointegration in this region as much as possible and maintain tissue stability in the long term. In this respect, it seems that the surface treatment has advantages to maintaining the peri-implant bone stability.
The problem is that this same way of thinking is applied to zygomatic implants. However, many concepts applied to conventional implants cannot be directly transported to zygomatic implants, as we will see below.
The first concept that we have to understand is that the zygomatic implant's main osseointegration area will occur in the body of the zygoma bone.
Osseointegration in the cervical region would be desirable only when there is a residual bone in that region, which is not always the case. It is prevalent for zygomatic implants to be completely externalized (extra sinus technique), only with slight support on the maxilla's residual bone.
Some zygomatic implants companies produce only one model of zygomatic implant for all clinical situations. However, others offer 3 implant design options that can be selected according to each specific situation.
For didactic purposes concerning the different possibilities, we will classify the zygomatic implants in 3 modalities according to the design of the cervical region:
Model I
In this zygomatic implant model, there are threads and surface treatment in the apical portion, the surface is polished in the intermediate region, and in the cervical portion, the implant have surface treatment and threads.
This kind of implant is indicated for situations where there is a large residual bone in the alveolar ridge region. Thus, it is possible to install the zygomatic implant so that the cervical region remains with complete bone insertion. The surface treatment and threads aim to favor osseointegration in this region. In conventional implants, the presence of this collar can decrease bone loss (1).
Although this osseointegration at the level of the alveolar ridge does not have many contributions in the final stabilization of the zygomatic implant as a whole, since the main anchorage will be in the body of the zygoma, this situation is theoretically desirable due to the tissue stability that osseointegration promotes in this region.
But why did I use the term "theoretically"?
Because such a concept makes sense, but there are one crucial factor to consider. The precise case selection for zygomatic implant.
If we look at the zygomatic implant cervical portion where the threads and surface treatment exist, ideally, a good part of this segment should be intra-bony. However, a warning signal sounds here!
Probably you are likely treating a case with a zygomatic implant in which you did not need a zygomatic implant!
Take a look at the case below. I haven't understood the Allon4 concept at that time yet, and I treated the patient with zygomatic implant (what I would not do today). I just needed to tilt the distal implants a little and the case could be resolved without any zygomatic implant.
If there is such bone availability in this region of the ridge, it would probably be possible to tilt the conventional distal implants and solve the case with Allon4 Standard, I mean, without the need for zygomatic implants.
Even in thin alveolar ridge cases in the premolar region, it is possible to use the palatal approach in distal implants. The implant head is left with the palatal turns exposed, and the implant is anchored in the canine pillar region.
But, what would be the ideal indication for this zygomatic implant design?
Situations where there is a thin residual bone in the premolar region, where the implant head needs a more posterior position (due to the maxillomandibular relationship), not allowing a conventional implant to be angled to the anterior one, that is, in a case where it is not it is possible to perform Allon4 Standard (unusual situation).
Here there is another subtle but also clinically relevant detail.
When we think about installing the implant, maintaining this residual bone crest to maintain osseointegration throughout the implant's cervical, we need to leave this implant with the head palatal displaced concerning the residual ridge.
It is a reasonable position, but it is possible to let the prosthetic screw's emergence strictly at the alveolar rim level, which further improves the prosthetic outcome.
If we do that, notice that the entire cervical region treated from the implant ends up being out of the bone. As a result, in addition to losing the purpose of this surface (which would be cervical osseointegration), this area is now covered only with soft tissue.
The friction generated by the movement of the soft tissue (during the speech, chewing, and brushing) over the threads can lead to tissue dehiscence.
If you could choose from one of the following possibilities, what would you prefer?
1) have tissue dehiscence with an implant with a threaded design and with surface treatment, or 2) have dehiscence with a zygomatic implant with a smooth and polished cervical surface.
Which would accumulate less food debris and plaque? Which would promote the patient the best ability to maintain hygiene? Which would respond best to possible future soft tissue covering procedures?
The answer is obvious.
So this type of zygomatic implant conceptually makes sense but in practice, not so much. In virtual planning, it is possible to foresee the characteristics and nuances of each case and thus define whether this implant model will make sense or not.
Regarding the range of sizes available, these implants with this configuration come in various sizes, ranging from 35mm to 60mm. It means that we have solutions for the majority of cases of Hybrid Allon4 and Zygoma.
When we do Allon4 Zygoma, the anterior implants are almost always wholly externalized. Because of that, this kind of zygomatic implant cervical threads and surface treatment would not bring any advantage (neither for osseointegration nor for tissue stability). These implants commonly end up being much longer than the posterior ones. It raises a question about whether it makes sense to have this model's zygomatic implants larger than 52.5 mm with this cervical treatment.
Model II
This zygomatic implant model has surface treatment only in the apical portion and is indicated for severe atrophy cases where we will have fully exteriorized zygomatic implants (extra sinus technique).
In these situations, we recommend installing the implants so that the implant's head is supported by the residual bone.
A subtle detail to be questioned in this model is the reason for the cervical step. A small change in the cervical area, letting it slightly concave, could promote better tissue accommodation and improve the prognosis of tissue stability. I proposed this implant design in 2018, and we hope that soon some company will think about this possibility.
Model III
That is the design of the zygomatic implants traditionally used. They have threads in all their extension, being able to be machined or with surface treatment.
Neodent/Straumann recently launched a new line of zygomatic implants where it maintained the threads and surface treatment throughout the implants but left a segment of the cervical region without threads, which may favor tissue accommodation.
Nobel Biocare has a line of zygomatic implants with surface treatment but without threads.
No randomized studies are comparing which of these alternatives is the best in the long run. Therefore, clinical sense and individual experiences are our only forms of decision.
I have seen clinically that there is a tendency for migration of soft tissue when the implants are completely externalized, and we use implants with threads. Because of it, I decide to opt for smooth implants in such situations until we have some scientific evidence of the best alternative.
3) The Thickness of Zygomatic implants
As with the lengths, there is a wide variation between the zygomatic implants' thickness between the different brands.
The table below compiled the implant body dimension of the main zygomatic implant systems:
Zygomatic implant fracture is rare, but there are some reports in the literature. It may be related to the lack of splinting of the implants with the metal bar, excess of the anterior cantilever, or lack of support of the implant head in the cervical region.
For more than 12 years, I have been using a zygomatic implant with an apical thickness of 3.85mm and have never had this type of complication. The use of wider zygomatic implants (like NobelZygoma 0) in my vision is not justified. It can be challenging to install in some patients in quad-zygomatic implants or even could let the zygoma's outer cortical too thin, causing cracks or even complete cortical fracture.
The unique zygomatic implant company that offers different alternatives for implant thickness is the SouthernImplants (3.4 e 4.1mm).
4) Zygomatic Implant Surface Treatment
Before thinking about whether surface treatment is essential in zygomatic implants, we must ask ourselves what type of bone we are inserting into our implant.
The zygomatic bone is different from the posterior maxilla bone (3). In the zygomatic region, there is a high tendency to corticalization due to the powerful masseter muscle's insertion.
If we were to make an analogy, we could say that the zygomatic bone is a mandible-like bone.
Surface treatment improves osseointegration in the case of low-quality bone (2). In the case of good-quality bone, the surface treatment does not present any additional gain, or may, according to Balshe (4), even be worse in certain situations.
In addition to being a corticalized bone, there is a peculiarity of zygomatic implants, which is the possibility of tetra-corticalization; that is, the zygomatic implant passes through the zygomatic region from anterior to posterior and may have an anchorage in 4 bone cortical.
In such a condition, where we have an excellent cortical bone and an implant anchored in 4 cortical, is surface treatment essential? What would be the reason?
Osseointegration is not a problem in the zygoma area. Companies sometimes seem to seek solutions to problems that do not exist.
But would the surface treatment have any disadvantages?
Maybe.
There is a frantic rush to increase BIC (bone-to-implant-contact) in implants. BIC increases have been placed as the holy grail in biomaterials research, geometry, and surface treatment.
It is here that the "super-specialist" problems begin. The more graduated and the more the advancement in the academic career, the greater the tendency to have what we can call a kind of "tunnel vision." The professional delves so profoundly into specific detail of a system and forgets to see the whole. He starts to study only one specific plant and forgets to look at the forest.
What do we seek with osseointegration? Anesthetic, functional and stable rehabilitation over time. It has to do with BIC, but to some extent. After spending years studying how to increase BIC by x%, it may not have the slightest clinical repercussion.
In this respect, Balshe elegantly pointed out:
In other words, other factors contribute to the success of osseointegration in addition to BIC, and here we may have the downside of surface treatment.
In case of the need to remove the zygomatic implant for any reason, the surface treatment will promote an increase in torque for removal of the implant.
From a scientific point of view, personal experience reports have little validity but can serve as a starting point for investigation.
After 12 years of performing a zygomatic implant without surface treatment, according to my case series, I can say that this is the kind of surface I want to continue using unless I come across scientific evidence that proves otherwise.
5) Zygomatic Implant Assemblers
It is prevalent to install zygomatic implants with a high insertion torque value. Too high torque values can damage the prosthetic connection or cause the assembler or screw to fracture. For this reason, it is crucial, during the surgical installation of the zygomatic implant, that the surgeon does not insist on proceeding with the installation if the torque is too high.
Some surgeons prefer to start the installation with the handpiece and, after reaching 45N torque, the installation of the zygomatic implant is completed with the manual installation key. The installation key allows the use of high manual torque values. As it does not give us the possibility of an accurate reading of the insertion torque, this perception ends up being something subjective, and very high torques can be reached exceeding the assembler's mechanical tolerance threshold.
But what would that threshold be? What can we consider a torque too high?
The most of the zygomatic implant companies do not give us objective information about the zygomatic implant maximum installation torque.
Evaluating the zygomatic implant main companies catalog, most of them do not provide surgeons with this information.
I found this information only in the catalog of SIN Implant System and Titaniumfix.
SIN Implant System guides a maximum installation torque of 80N.
(Print from the SIN Implant System catalog)
I have had several cases of problems with the assemblers of the zygomatic implants of SIN Implant System. Screw strength problems during installation may have occurred due to the high torques, and, perhaps, I have exceeded the maximum values. However, the problems occurred both during the installation of the implants, but there has also been a problem with the screw locking during the removal of the assembler BEFORE the installation (performing a pre-test before installing the implant in the mouth).
Recently, SIN Implant System completely modified its zygomatic implant line, and we will wait to see the problem has been solved.
If we think of values of 80N.cm of insertion torque in zygomatic implants, this could not be considered too high value, but something that we can control, even subjectively. However, the ideal would be for the systems to support higher values for our security (despite being unnecessary from a biological point of view).
Titaniumfix recommends a maximum installation torque for the zygomatic implant of only 45N.cm.
It represents an unfavorable situation in a zygomatic implant system. Having to install a zygomatic implant that cannot exceed 45N.cm would be like having a Ferrari on a race track and not exceeding the speed limit of 80km/h. It does not make any sense.
What draws attention is that these implants have an internal connection and as the platform is 0o they can be installed without an assembler, which theoretically would have more resistance compared to implants with assemblers.
The subject of insertion torque is something, to some extent, a little open to much discussion. On the one hand, some surgeons value and prioritize implant design optimized for maximum primary stability. On the other hand, some surgeons point out that high torques are not desirable and prefer smaller insertion torques. In that case, they plan to assign part of the responsibility to the surface treatment.
However, regarding the possibility of immediate loading, the search for primary stability is a consensus among the majority.
But what would be the minimum torque to load immediately safely? Is it possible to load immediately even with lower torques? In a zygomatic implant, can we apply the same way of thinking as conventional implants?
Furthermore, is excess torque harmful to osseointegration?
We still do not have all the answers objectively. However, we have a lot of information that needs to be compiled, digested, and disseminated so that we clinicians can put this knowledge into practice. We discussed this subject in more depth in this post.
The fracture of the assembler's screw during the installation of the zygomatic implant is extremely unpleasant. It generates stress for the surgeon and can significantly increase the surgical time. When such a problem occurs, we have no other choice but to go for the solution.
In this other post, we discussed the screw fracture problem and possible methods of solving this problem in more detail.
5) Zygomatic Implants Prosthetics components
The case's ideal prosthetic resolution will depend mainly on the final position in which the zygomatic implant was installed. The choice of the ideal prosthetic component aims to optimize the prosthetic screw's emergence and maintain a vertical position compatible with the thickness of the soft tissues.
Thus, the greater the range of possibilities for heights and angulations, the better for the surgeon or prosthetist to ideally end the case.
Most zygomatic implant systems have implants with the implant head already angled to the implant body. This angle can be 45 ° (SIN, Brånemark System, NobelZygoma 45 °) or 55 ° degrees (SouthernImplants, ImplantSwiss).
We have noticed in clinical practice that there is a tendency for zygomatic implants with a 45 ° head to promote good prosthetic resolution, but an increase in this angle would improve this relationship with the ridge.
Therefore, perhaps implants with a 55 ° pre-angled head can be an advantageous alternative.
Once the implant is installed, it is necessary to choose the prosthetic component with the ideal height.
Sometimes when using the externalized technique (extra sinus), the implant head is only supported by a slight touch in the alveolar ridge. In such situations, the lower 2mm components are usually needed.
The important thing is to individualize each case accordingly; therefore, several heights must be available by the implant system. Even with zygomatic implants having the head already angled 45° or 55°, the possibility of installing angled components on these implants can further optimize the ideal ratio of the emergence of the prosthetic screw.
Some companies offer this alternative. More recently, some zygomatic implant systems have started to produce 0° head implants (JDentalCare, Noris, NobelZygoma 0°, IDCImplants, Titaniumfix, Neodent). An advantage would be greater flexibility of options in prosthetic resolution in addition to the connections being internal.
Another advantage is that these implants can be installed without the need for assemblers, which minimizes the chance of mechanical complications during installation under high torque.
Once the zygomatic implant is installed, the prosthetic emergency's anteroposterior position can be selected with the fitting of the prosthetic component. However, we have made this fine adjustment in the implants that already have a 45 ° angled head, just rotating the implant itself (with an assembler) without any significant problems.
The supposed flexibility of installing 0 ° implants can only be real if there is a wide range of prosthetic component alternatives. We have to understand that we need options that give us both angles and heights alternatives. It is not always true for some systems.
Let's take a look, for example, at the Neodent zygomatic implant system.
0 ° implants with internal connection. However, take a look at the prosthetic components available for these zygomatic implants. From what we have seen in our clinical situations, at least 45 ° angulation is what we need to solve our cases. Ideally, this angle could be 55 ° or even higher.
The use of 30 ° and 17 ° angled mini-abutments on 0 ° zygomatic implants is rare, and, straight mini-abutments, we can say that they will never be used in zygomatic implants.
So why do companies manufacture them?
This type of straight abutment has its indication only for implants installed in the paranasal region, that is, they are not zygomatic implants, they are long implants (around 20 to 26mm).
Thinking that we will use a minimum angulation of 45o in zygomatic implants, the system offers us only 2 prosthetic component height options, 1.5 and 2.5 mm, which could be an important limiting feature of this system.
Besides, this component is fixed with a lateral through the screw and leaves a hole in the abutment side surface.
Can this orifice be a plaque retentive factor if the gingival recession occurs in this region?
We do not yet know the relevance of this, and long-term studies are non-existent. Some companies have a choice of components with an angle of 45 or 60 ° like NobelZygoma0 °.
In addition to the 45 or 60 ° options, the Noris implant system features an intermediate 52 ° option. Some advantage of Noris Multi-Unit is the absence of lateral screw cavity.
Noris seems to be a perfect solution for all clinical situations. However, when we evaluate in more detail, we see that we still don't have a perfect zygomatic implant system.
Although this mini-abutment (Multi-Unit) is sold as having different transmucosal heights, it works like an extension of the implant length and not an abutment with different gengival heights.
It causes the emergence of the prosthetic screw to move in the buccal-palatal direction while defining the ideal height according to the soft tissue's thickness, as in the picture below.
An angled abutment with real height variation would be like that from Nobel Biocare.
In this way, it is possible to select the ideal height without interfering with the prosthetic screw emergence's buccal-palatal position.
So that way, we have the ideal solution? NO!
A potential problem to be investigated in this type of abutment is that the fixation screw's orifice remains in the palatal region. The palatine mucosa is resistant to tissue dehiscence, so much so that it is routine to install implants with a palatal approach, leaving some exposed threads.
However, we still do not know whether this orifice in this kind of mini-abutment will cause plaque accumulation or potential complications in tissue stability, mostly when located more superficially about the gingival margin.
TitaniumFix components, in addition to only 17 and 30-degree angles, have only two heights available of 2 and 3mm. But the worst aspect of this system is that the screw is inserted into the abutment side. Any small tissue dehiscence may expose this hole to the oral environment.
If using zygomatic implants with an angle of 45o, we have an optimal position concerning prosthetic emergence; the possibility of using angled components is an advantage of the Nobel and DSP systems.
6) Scientific publications
Regarding scientific publications and time on the market, no zygomatic implant system can match Nobel Biocare. Among the zygomatic implant models currently available, undoubtedly the zygomatic implants with head 45o and external hexagonal connection are the types of zygomatic implants most researched.
All-new forms of 0o prosthetic connection are still being validated by the clinical studies to come.
It is worth evaluating whether you will want to participate in these "tests" of these new systems or use something already established in the literature in your private clinic.
When it comes to dentistry, I never want to be the first to use something recently launched on my patients or be the last who is still using a specific product.
7) Zygomatic Implant Surgical kit
It is interesting to note that some zygomatic implant systems still insist on the initial drill in the spherical shape, which is terrible for the initial drilling. In addition to promoting more significant oscillation, this type of drill has great difficulty and instability for cutting oblique surfaces.
Significant advances have taken place in recent years, and most companies have evolved in this regard and have started to offer a lance format for initial drilling.
However, the pioneer Nobel Biocare, SIN Implant System and Dental Care, still provide spherical drills for initial drilling in their zygomatic implant systems.
Some companies like SouthernImplants and TitaniumFix commercialize both initial spherical drills and spear.
Regarding the subsequent drill sequence, there is significant variation about the thickness of the drills (due to the variation in the implants' thickness between the different zygomatic implant systems), and the most of systems only provide a single length of drills.
It is necessary to use lip protector in some clinical situations when osteotomy is performed on patients with reduced facial dimensions. On the other hand, zygomatic implant systems such as Implance, Nobel Biocare (NobelZygoma), ShoutherImplants, JDentalCare and ImplantSwiss offer 2 options for drill sizes, which facilitate milling in specific clinical situations.
On the other hand, Noris offers the most complete system of zygomatic implant drills, offering drills of various sizes for the most different clinical situations.
See below the main designs of the drills of the different zygomatic implant systems.
Conclusion
There is no ideal zygomatic implant system. Mastering the concepts discussed above will make you understand the advantages and limitations of each system. The dental implant company that attends to these concepts can create a unique zygomatic implant system on the market and will undoubtedly promote great help so that the surgeon can solve the most diverse clinical situations in the best possible way. In the meantime, we need to adapt to the limitations of the zygomatic implant systems available on the market.
What zygomatic implant systems have you been using?
What have been your challenges?
Share your experiences below, and we will together evolve our technique and pressure companies to evolve for us and with us.
REFERENCES
(1) Koodaryan R, Hafezeqoran A. Evaluation of Implant Collar Surfaces for Marginal Bone Loss: A Systematic Review and Meta-Analysis. Biomed Res Int. 2016;2016:4987526. doi:10.1155/2016/4987526 - https://pubmed.ncbi.nlm.nih.gov/27493957/
(2) Goiato MC, dos Santos DM, Santiago JF Jr, Moreno A, Pellizzer EP. Longevity of dental implants in type IV bone: a systematic review. Int J Oral Maxillofac Surg. 2014;43(9):1108-1116. doi:10.1016/j.ijom.2014.02.016 - https://pubmed.ncbi.nlm.nih.gov/24679842/
(3) Bertl, K. et al. MicroCT-based evaluation of the trabecular bone quality of different implant anchorage sites for masticatory rehabilitation of the maxilla. J Craniomaxillofac Surg 43, 961-968, doi:10.1016/j.jcms.2015.04.008 (2015). https://pubmed.ncbi.nlm.nih.gov/26027862/
(4) Balshe AA, Assad DA, Eckert SE, Koka S, Weaver AL. A retrospective study of the survival of smooth- and rough-surface dental implants. Int J Oral Maxillofac Implants. 2009;24(6):1113-1118. https://pubmed.ncbi.nlm.nih.gov/20162117/