Ever since Brånemark introduced his concept of osseointegration back in 1977, healing times of 3 months at the mandible and 5-6 months at the maxilla are recommended. Even today, these protocols remain valid and are followed by many dentists around the world.
However, over the last few decades, multiple studies have shown that immediate or early loading, once deemed detrimental, is now a viable and safe option, particularly in edentulous patients – those missing all of their teeth in one or both arches.
So what’s changed?
Well…
A series of randomised controlled trials involving thousands of participants have helped to sway opinion in that they showed no significant difference in bone fusion, bone loss or prosthesis/implant failure whether implant loading was delayed, early or immediate.
But while it’s obvious that biological factors remain the same, two key essentials have also changed our views on implant loading:
- The understanding of the osseointegration process and the factors that affect it, and
- The technology surrounding implants – particularly concerning implant surface design
Let’s take a closer look at each in turn:
The concept of osseointegration
Osseointegration, as we know is critical for implant stability and is a prerequisite for long-term success. Without it, implants won’t remain stable enough to support a restoration tooth or prosthesis.
Yet, we also know that the tissue-implant interface is an extremely complex region of interaction involving biomaterial and biocompatibility. Furthermore, we also know that it’s affected by the mechanical stimuli of our local environment like smoking or medical issues like diabetes.
The good news is that thanks to decades of study, we have a better understanding of the stages of integration from the interlocking of bone tissue through to biological bone fixation, and indeed, the outside factors that influence or affect it.
Moreover, given the right technology. we know that greater implant anchorage can be manipulated.
This brings us to our second key factor…
Implant design
Just like our understanding of osseointegration, implant technology has developed greatly over the last couple of decades. Because we now have a greater understanding of exactly how the interaction between the implant and bone tissue plays out, it enables manufacturers to make vast improvements to implant surfaces even down to micro and nano-scale design.
Implant-incorporated nanomaterials are now able to interact better with tissue cell proteins while initiating the growth of osteoblasts (bone-forming cells). These factors work together to promote speedier osseointegration and stronger bone-to-implant anchorage. Additionally, updated implant designs involving improved surface areas also play their part.
Essentially, a changed consensus coupled with technological advancements and clearly defined protocols now allow clinicians to confidently place an implant and immediately load a restoration without compromise. This has led to a paradigm shift in the daily clinical practices surrounding implant placement.
So, while a waiting time of 3 months or more is still a valid protocol, it’s important to know that it isn’t the only option.
How immediate loading benefits the patient
Of course, there are advantages to immediate loading for the patient too. They don’t, for example, have to endure uncomfortable full or partial dentures while awaiting rehabilitation. Nor should they expect compromised functionality or aesthetics while waiting for their implants to osseointegrate. So, for any clinician who has their patient’s best interests at heart, immediate loading should certainly be a consideration given the right indications.
Old habits die hard
Let’s face it, nobody likes “Change for change’s sake” and understandably, dentists may be reluctant to alter what’s currently working for them. So it’s worth noting that at present, based on current literature, a 2-4 month delayed loading time is still the norm rather than the exception.
However, clinicians should always consider what’s best for each patient in each case and in some instances, that might be to immediately load.