All dental implants today are made from the same basic material which is titanium. The reason that all dental implants are fabricated from this metal is because titanium has been shown to be so biocompatible that bone will actually bond to its surface. This process, discovered in Sweden in 1968, of bone fusing to the titanium surface was given the name, osseointegration. Although this process of osseointegration is the common denominator to all dental implants, there are significant differences and variations between the great number of dental implant systems currently available, making the choice of the implant by the surgeon a critically important decision.
One-step vs. two-step dental implants
A two-step implant requires two surgical procedures before the implant is ready to be utilized for tooth fabrication. One surgical procedure is necessary to push the gum back for the placement of the implant, followed by stitches over the area. At the end of the healing period the same surgery is then performed to uncover the healed implant, in order to place the crown. In 1974 a group of preeminent Swiss dental researchers invented the one-step dental implant which is placed at the gum level rather than submerged beneath the gum. This procedure eliminates the need for a second surgical procedure and shortens the healing time by weeks or months.
Types of titanium
There are four grades of titanium that implants are typically made from. Type I titanium is the weakest, softest form of the metal while type IV titanium is work hardened, tempered titanium. The problem with the softer forms of the metal is a tendency for the implant to become fatigued and fracture over time. All implants placed by our office are made exclusively from grade IV commercially pure titanium, making implant fractures almost non-existent.
Bonding strength of the implant is determined by surface area. In the early days of implant therapy we thought that there were two factors determining the bonding strength of the implant to the bone, namely, the length of the implant and the diameter of the implant. After 10 years of research the Swiss realized that if they roughened the surface of the implant by making micro porosities by dipping the implant in a strong acid bath, and then made larger porosities by a special sandblasting method, they could increase the surface area for bonding of the implant by about 30%. They named this pioneering surface technology SLA. This is an extremely important innovation because many patients have limited bone available, and or poor quality bone for dental implants. These patients were either not considered candidates or required extensive bone grafting procedures before implant placement was possible. Now, because of this surface modification, shorter implants may be used with the same strength as a longer conventional (smooth) surface implants. Patients require fewer grafting procedures and the implant is stronger in patients with poorer quality bone.
Another direct result of the use of the SLA surface which was not anticipated at the time of the original research was a significant decrease in the healing time of the implant. Instead of the usual healing time of 4 to 6 months, many times an implant may be fully integrated and ready for a permanent tooth replacement in as little as 6 weeks.
Variety of Implant Sizes
Most dental implant systems are basically one size fits all. In general, this means that the same diameter implant is used regardless of whether the intent is to replace a small front incisor tooth or to replace a large back molar. This is significant because a narrow implant placed for a large molar tooth leaves large spaces at the gum line which becomes a constant source of annoying food trapping.
Implants come in various lengths as well as diameters depending upon the specific tooth it is intended to replace. Because the implant is specifically designed to replace small, medium, and large sized teeth, food trapping is generally a thing of the past.