Soft tissue approach for implant installation
Dehiscence around a dental implant is usually caused by poor implant positioning. The use of soft tissue grafting to treat this kind of complication is documented in a study with five-year results (Zucchelli et al. 2018) (Figure 1). The speaker outlined the steps involved in this procedure:
- switch to an abutment with the smallest diameter possible to allow the tissue to grow around it
- raise a partial thickness flap to keep the papilla intact and move it coronally to displace it
- treat the implant surface (only if exposed/probable before surgery)
- anchor a connective tissue graft to the de-epithelialised papilla and ensure it is completely covered by the flap
“Dehiscence around a dental implant is usually caused by poor implant positioning”
The aim is to increase the soft tissue thickness at the transmucosal level. The speaker pointed out that the soft tissue margin can continue to grow following this treatment, and tends to ‘creep’ down onto the crown. This can be observed by comparing the ‘before and after’ photos (Figure 2). A critical point for the success of this approach is that the loss of bone is only on the buccal aspect and is not interproximal. This technique is suitable for well osseointegrated implants without any signs of peri-implantitis.
The speaker went on to describe the five-year outcomes of this approach for prosthetic and soft tissue management. Despite the poor implant positioning and absence of buccal bone in the patients include in the study, they achieved a mean coverage of 97.2% of the level of the adjacent teeth and complete coverage in 79% of the cases. Patients were highly satisfied with this treatment (especially considering that the alternative was implant removal). The most impressive outcome reported was the continued increase of soft tissue volume (‘creeping’) over time.
“The aim is to increase the soft tissue thickness at the transmucosal level.”
The same technique was used in one of the cases presented by the chair at the start of the presentation. The case involved an implant which still had connective tissue adhering to the surface, but no buccal bone covering it. The speaker illustrated how the technique fulfilled the treatment objectives to not only mask the transparency, but also increase soft tissue thickness in the absence of buccal bone and even also replace the suprabony component of the soft tissue (or so-called ‘transmucosal area’) (Figure 3).
The speaker explained that the increased thickness achieved by this approach maintains the integrity of the margin, preventing the inner inflammatory area from becoming thicker than the remaining healthy portion. The ‘soft tissue approach for implant installation’ (Zucchelli. in press) is a protocol to prevent aesthetic complications based on the following principles:
- delayed approach
- correct 3D-guided positioning of the implant
- split thickness flap advanced coronally
- soft tissue graft to increase the thickness of the transmucosal zone
- immediate temporary crown to support the displaced flap and prevent its collapse
“Increased thickness maintains the integrity of the margin”
From an aesthetic point of view, the speaker said it makes more sense to increase the thickness 3–4mm coronal to the margin – the transmucosal area – than to augment the bone in a more apical area. Buccal bone does not have a significant influence either on aesthetics or on stability, provided that a soft tissue graft has been performed to compensate for the insufficient bone in the buccal crest.
Soft tissue augmentation also improves the emergence profile, which in turn makes it easier for the patient to clean the area and minimise plaque accumulation.
One of the questions addressed by the speaker was: ‘Is it possible to follow this protocol in the case of immediate implant placement?’ His answer was yes. But because the papillae are smaller, the graft should be applied to the inner face of the flap and then the flap should be displaced coronally.
“Soft tissue augmentation also improves the emergence profile”
The same protocol can be successfully used in the molar region, where it has been shown that peri-implant crestal bone loss is associated with mucosal thickness (Linkevicius et al. 2009; Stefanini et al. 2016). Recently, the literature has highlighted the beneficial effects of soft tissue augmentation procedures in mainting peri-implant health (Thoma et al. 2018; Giannobile et al. 2018).
Some conclusions can be drawn about the ‘soft tissue’ approach:
- it is ideal for treating peri-implant mucosal dehiscence
- in the aesthetic zone, this approach is critical for successful aesthetic outcomes
- in the posterior area, the approach is recommended for improving patient maintenance and peri-implant health