Soft Tissue Volume Changes After Immediate Implants With Two Different Techniques

Overview

The aim is to comparatively evaluate the soft tissue volume changes that occur after tooth extraction and immediate dental implant placement using two different surgical techniques. These techniques are: the Socket-Shield technique and conventional immediate placement. The null hypothesis is that the Socket-Shield technique better maintains soft tissue volume after partial tooth extraction and immediate implant placement compared to the conventional technique. From a sample of 20 patients, they will be divided into groups of 10 and will be randomized using the random.org program. The soft tissue volume will be digitally recorded by intraoral scanning before tooth extraction and 6 months later. The soft tissue dimensional changes produced will be digitally evaluated and statistically analyzed.

After tooth extraction, the supporting tissues, bone and mucosa will undergo a loss of volume associated with the loss of the cementum-periodontal ligament-bone attachment complex. This alteration in volume can affect aesthetic results, especially when the tooth involves the anterior area, where the alveolar bone is narrower. To compensate for the lost volume loss, some authors promote delayed implant placement, which would facilitate soft tissue management after healing. The conventional immediate implant placement technique proposes the use of bone regeneration biomaterials in the space between the implant wall and the residual vestibular bone. The aim of this technique is to compensate for this bone resorption, thus improving the aesthetic results. In the same sense of compensating for the resorption that will occur, some authors recommend the use of soft tissue grafts in the same operative act of extraction and placement of the immediate implant. Some years ago, some authors presented the technique of partial extraction of the tooth as an alternative to the conventional technique of immediate implant placement after extraction with the aim of avoiding or minimising this resorption. The technique consists of leaving a piece of tooth (shield) inserted in the vestibular alveolar bone area so that the resorption process is slowed down. The presence of bone between the dentine wall of the tooth fragment and the implant has been demonstrated in both animal and ex-vivo histological studies. From a clinical point of view, the Socket-Shield or partial extraction technique has been shown to maintain the vestibular volume in post-extraction implants placed using this technique in both posterior and anterior areas with high aesthetic compromise, maintaining adequate clinical values and patient satisfaction. On the other hand, a 2015 systematic review, comparing immediate and delayed implantation techniques, reports no significant differences between the two, especially at the soft tissue level, although it mentions a lack of quality in the RCTs analysed. A 2017 randomized clinical trial compared the conventional immediate implant placement technique with the delayed or early implantation technique, advising against the former when aesthetics were compromised and limiting it to well-selected cases. In contrast, another more recent randomized clinical trial found no aesthetic, clinical or radiographic differences between the two techniques, and reported similar levels of patient satisfaction. Likewise, a higher rate of early failure has been found in the immediate implantation technique, mentioning the lack of randomised clinical studies comparing both techniques, especially in terms of soft tissue volume changes. A recent randomised clinical study comparing the Socket-Shield technique with the conventional implant placement technique found better levels of marginal bone and pink aesthetic assessment in the former, considering it a safe and feasible technique in the anterior sector. Given the lack of evidence in the literature, there is a palpable need for clinical studies to compare the best technique and/or timing of implant placement after tooth extraction.