“I would fill the gap in any case”

Prof. Jan Cosyn, Ghent University, has a lot of experience in the controversial field of timing of implant placement. During Osteology Barcelona, he sheds light on the question - Immediate implant placement: when is hard and soft tissue grafting indicated? 

Dr. Giulia Cerino | Switzerland

Immediate implant placement is an appealing treatment for patients and your research into this topic is extensive. Where do you see the biggest advantages?

Prof. Cosyn: The time gain is the biggest advantage. First, from the perspective of the patient, because he or she presents with an urgent problem and the tooth replacement is performed in one day—the implant and the temporary crown. Secondly, the practitioner performs only one surgical procedure and one prosthetic procedure. This is really optimization of time.
 

Do you see a global trend towards more and more immediate implant placement?

Prof. Cosyn: Yes, the trend is increasing everywhere. More and more practitioners are performing immediate implant placements because there is more knowledge about the treatment concept and clinicians are more aware of the pitfalls. However, this does not mean that the risks of immediate implant placement are fully respected. What worries me most is that the treatment is also expanding into untrained hands.
 

You have recently published a systematic review showing that immediate implant placement has a higher risk for early implant loss than delayed implant placement.¹ What are the reasons?

Prof. Cosyn:  We did several subgroup analyses on the data because the entire study was composed of eight different clinical comparative studies. Thanks to the analysis what has become clear is that the use of post-operative antibiotics has a relevant impact on early implant failure. Not prescribing antibiotics in case of immediate implant placement results in a 7% higher risk of failure.
 

Is it not a general recommendation to prescribe antibiotics after treatment?

Prof. Cosyn:  Prescribing antibiotics is not a general recommendation in the context of any implant procedure. This has not been shown or at least there are no solid data to confirm it. The number needed to treat is quite high to have a benefit in the context of standard implant placement, but this is not the case when you are dealing with immediate implants. It is not possible to generalize for all procedures, but for type I implant placement the use of antibiotics should be considered, and this result is also in accordance with the systematic review of Lang et al. already published in 2012.²
 

Do you think that hard and soft tissue in the context of immediate implant placement, e.g. “filling the gap”, could make immediate implant placement more predictable?

Prof. Cosyn:  I honestly do think so. Ten years ago, there was a debate about the need for socket grafting following immediate implant placement. Now, we have three randomized controlled clinical studies^3-5 and the last one by Sanz et al.⁵ is clearly showing a statistically significant difference in favor of socket grafting versus no grafting. So, for maintaining the integrity of the buccal bone wall it is imperative to perform grafting. However, we also know that this grafting may be not good enough as it only reduces buccal bone resorption, it does not eliminate it. Different case series from various research groups show that advanced midfacial recession occurs in about 20% of the cases; which is still too high despite socket grafting and a proper diagnosis. Therefore, the need to compensate opens the indication for soft tissue grafting in most of the cases.
 

What are the situations in which you would advise including regenerative treatment as part of the overall treatment?

Prof. Cosyn:  In the front area especially. I think there is no longer a single situation where I would just leave out socket grafting. Interestingly, for the first time it has been shown by Sanz et al.⁵ that the additional effect of socket grafting does not depend on the size of the gap. The proportional effect is the same for either large or small gaps. So, the clinical recommendation is to fill the gap in any case.
 

When is soft tissue grafting indicated in the context of immediate implant placement?  

Prof. Cosyn: I would say frequently. But let's start with the worst scenario, situations where there is no buccal bone anymore. If you have this situation around a tooth, we know that root coverage procedures are predictable as long as there is at least 1.5 mm of gingival thickness. In case of an implant, the thickness must be greater, 2 mm, for the simple reason that there are no inserting supracrestal collagen fibers. There are no data on this, only common sense. Since 2 mm soft tissue thickness are only present in about 10% of the cases, starting from the worst case, this means that in 90% of the cases soft tissue grafting is necessary to be completely predictable.
 

Do new techniques such as 3D imaging, guided surgery or new implant designs make immediate implant placement more predictable also for less experienced surgeons?

Prof. Cosyn:  They can certainly help. My recommendation is to have a CBCT before tooth extraction and immediate implant placement in each case, to make an appropriate diagnosis and to evaluate the risks. It is the only way to visualize the buccal bone wall, its thickness and morphology, and the thickness of the soft tissue if lip retractors are used.

Guided surgery is also important because in type I implant placement, the most important mistake is an implant that is placed too much to the buccal aspect. This can happen easily in untrained hands and no CTG can treat the resulting midfacial recession here. So, to prevent this possibility, the use of guided surgery is a plus especially for less experienced surgeons.
 

The use of short and narrow implants could avoid regenerative procedures? 

Prof. Cosyn: No, I don’t think so. Short implants are difficult to use in an alveolus because you need proper bone anchorage. Usually we use longer implants, 11 to 13 mm implants are quite standard for this treatment approach. More important is to use small diameters, 3.5 – 3.6 mm, even in central incisor position to stay away from the buccal area. And don’t forget, graft the gap in any case.

Dr. Giulia Cerino | Switzerland

Manager Medical Communications
Geistlich Pharma