Implant Surface Preparation with SLActive

In addition to the SLA method, there is another method called SLActive, which is an abbreviation of Sand blasted Long grit Acid etched Active. In the SLActive surface preparation method, bone formation is accelerated by increasing mineralization and the bone-implant connection is better. Dental implants with SLA and SLActive surface coatings are produced in the same way. Their only difference lies in the last stage of their production process. SLA implants are dried and ready to use after sandblasting and acid washing, or so-called etching. While SLActive implants, after etching, are stored under N2 gas protection and in a 0.9% NaCl (saline solution) solution, which is isotonic (meaning that it neither causes swelling nor shrinkage of cells). The key point in improving dental implants is how blood clots form on the implant. As shown in the figure; Features such as high chemical activity and hydrophilicity of the SLActive surface create a larger surface area for blood protein adsorption and fibrin network formation. This is the most ideal condition for blood clot formation and the initiation of the healing process. This technology reduces the six to eight week healing time in SLA to three to four weeks. Usually, dental implant failure occurs in the early stages of healing, that is, the first two to four weeks after implant placement. The SLActive surface can also accelerate bone healing and bone grafting with the fixture in cases of osteoporosis.

Implant surface preparation by the method: a) SLA and b) SLActive

In fact, the SLActive surface is the same SLA surface that prevents surface titanium oxidation with air, and manufacturers and companies of this method, including the famous Stroman company, claim that this method of treating the surface of the dental implant will provide a faster and better connection quality with the jaw bone. Studies have also shown the high success of this method, and especially in cases where a person has a systemic disease such as diabetes, the implant prosthesis in this method integrates with the surrounding bone and tissue as quickly as possible, and by reducing the bone formation time, the chances of implant operation success have increased. The SLActive method was actually invented by the same Stroman company and is also known as very rapid osseointegration. This method is faster than other methods by activating the implant surface and hydrophilicity, resulting in rapid blood absorption and contact with blood and bone formation. With this method, the adhesion of bacteria to the surfaces is much lower, and as a result, the possibility of infection is reduced. The figure shows the difference between the SLA and SLActive surfaces in blood and protein absorption.

The difference between the SLA and SLActive surfaces in blood and protein absorption

In recent years, many experimental and clinical studies have been conducted on surface preparation using the SLActive method due to the better bone bonding responses in this method compared to the previously mentioned methods. In this regard, Wennerberg et al. conducted a study on the hydrophilic properties of the SLActive method in 2011 and compared this method with the SLA surface preparation method. The results of their work, which were carried out on fifteen test samples of the implant surface, showed that the SLActive method had better hydrophilic properties than the SLA method, so that in the first six to eight weeks after treatment and bone formation, the SLActive method accelerated the bone formation process and worked more effectively. The figure shows the SEM images obtained from their research results. Also, according to their results, in addition to increasing the amount of connection and bone graft strength in the SLActive method, the speed of this connection and integration has also increased compared to the SLA method, at a certain time.

Comparison of the two implant surface preparation methods in Wennerberg’s research work Right image SLActive, left image SLA

In another study, Silva et al. compared the two SLA and SLActive methods in 2020. The results shown in the figure indicated that the SLActive surface preparation method accelerated the bone union between the implant surface and the gingival bone by two to four weeks and formed a better bone union.

Comparison of the durability of two implant surface preparation methods in Wennerberg’s research work

In a similar vein, in a study conducted in 2002 by Cochran et al., a two-step acid etching technique was performed by immersing titanium implants for several minutes in a mixture of concentrated HCL and H2SO4 heated to a temperature of over 100°C. According to their research results, the two-step acid etching produced microscopic roughness and accelerated the rate of osseointegration with long-term success of more than three years. The hypothesis of these studies was that two-stage acid-etched implants have topographic features that can adhere to the fibrin scaffold and promote osteogenic cell adhesion, thereby accelerating bone deposition. Surface wettability also promotes fibrin adhesion. This fibrin adhesion provides a contact guide for osteoblast migration along the surface. Their research also found that two-stage acid-etched surfaces showed greater bone-to-implant contact and less bone resorption than machined or TPS surfaces.