The introduction of dental implants in the field of dentistry has revolutionized the way missing teeth in dental patients are restored, owing to their excellent biocompatibility, durability and esthetics. However, a major factor that determines their long term retention and success, is the extent of ossoeintegration they achieve with the surrounding jaw bone.
For this purpose, various techniques have been devised by to enhance the capability of the dental implants to form a retentive and long term bond with the jaw bone, a brief account of which is given in the preceding text.
Modification of Surface Topography at Macroscopic Levels
It has been known since long, that dental implants that have a rough surface, are able to achieve better ossoeintegration in comparison to the implants having a smoother surface. Several methods are used for creating roughness on the surface of implants:
- Acid Etching – in this technique, the implants are immersed into a solution of a heated acid, which results in the formation of pits on the implant’s surface.
- Anodization – in this method, strong acids are applied to the implant’s surface, thereby resulting in the formation of an approximately 1µm thick layer which results in the formation of an electric circuit, where the implant serves as an anode. The end result is formation of a thick oxide layer that improves osseointegration.
- Sandblasting – fine particles of sand are accelerated towards the implant’s surface, resulting in the deposition of these particles, and forming various pits on the surface of the implant.
- Grit-blasting – very small particles of ceramics of Titanium are projected towards the implant’s surface at very high speeds. This results in the deposition of these particles on the implant’s surface, thereby creating surface roughness.
Surface Modification of Implants at Nanoscale Levels
While macroscopic surface modifications are quite helpful in increasing ossoeintegration in dental implants, it has been shown that surface modifications at the nano-level provide even better results. Nano-sized modification of the surface texture in dental implants can be achieved in the following ways:
- Self-Assembly Monolayers (SAMs) – this includes the deposition of specific molecules that have a strong affinity for the implant’s surface, and expose various functional groups which prove helpful in the process of ossoeintegration.
- Deposition of Nanoparticles – this techniques involves the deposition of nanomaterials onto the implant’s surface, by using the sol-gel technique. This method is commonly used for the deposition of nano-hydroxyapatite (HA) on the implants to boos ossoeintegration and enhance its biocompatibility.
Modification of Implant’s Surface Energy
It has been theorize that by enhancing the surface energy of an implants, the wettability of the implant is increased, thereby leading to a boost in ossoeintegration caused by increased interaction between the implant’s surface and the biological environment. Following techniques can be used to modify an implant’s surface energy.
- Hydrophillization of the Implant’s Surface – by depositing hydrophilic groups on the implant’s surface, the wettability is increased, thereby directly enhancing the potential for ossoeintegration.
- Plasma Treatment – this technique can result in the formation of positively charged implant surfaces, thereby enhancing osteoblastic adhesion on the implant’s surface, which results in a direct increase in ossoeintegration potential of the implant.
Bio-functionalization of Dental implants
This approach involves the modification of the implants surface and behavior with the help of various biological molecules, which are able to modify the biological environment of the implant, in favor of ossoeintegration, osteoblastic adhesion and wound healing processes. For this purpose, cytokines, several growth factors and other biological proteins have been successfully employed, either by using direct adsorption, covalent bonding or by using various carrier systems.
This text provides a brief overview of the various techniques and methods that are being employed for the surface modification of dental implants. The main idea behind surface modification is to create an implant surface, which is not only more biocompatible, but also conducive to wound healing and ossoeintegration.
Bruschi, Michela, et al. “Composition and Modifications of Dental Implant Surfaces.” Journal of Oral Implants 2015 (2015).
SHIBATA, Yo. “Surface Modification of Dental Implants.” Dental Medicine Research 30.3 (2010): 269.