The material surface and design of an implant play a crucial role in osseointegration (when the implant fuses with the natural bone rendering it stable, also termed as bone-implant anchorage). Apart from the material used for manufacturing the implant itself, surface modifications by physical and chemical means are adopted to roughen the surface of the implant for proper integration into the bone. Increased surface roughness of the implant leads to good bone apposition and a reduction in the healing time post-implant surgery.
What Is the Material Used for Implants?
As for the material of choice for manufacturing a dental implant-
Titanium and titanium alloys are widely used in the fabrication of modern-day dental implants, even though some manufacturing companies have started to adopt zirconia as an alternative material.
Aluminum oxide implants were also used in the early 1990s prior to the introduction of zirconia as alternative implant material in the market.
The recent material for manufacturing dental implants commercially has now been pure titanium because of its excellent biomechanical and biocompatible properties.
What Is the History of Dental Implants?
The discovery of dental implant material was in 1791 when Revered Geologist or mineralogist from Cornwall-William Gregor discovered Ilmenite, which Gregor deemed as a mysterious metal that was found at a stream bottom of Manaccan village in the United Kingdom (UK). Gregor then published it through reports, suggesting that this unidentified material was a new element. But it was not until four years later that German chemist Martin Heinrich Klaproth returned to the investigation of Ilmenite and isolated this new element. Martin suggested the name of titanium be given to this element in honor of titans (mythical giants who ruled the earth until they were overthrown by the Greek gods). When the research process started almost a century later in 1952 by Per Ingvar “Branemark” (The modern founder who was a pioneer in dental implantology by coining the term-Osteointegration) on Rabit femurs. It was Branemark, who illustrated that bone growth was very close and firm around the titanium alloy. This was the benchmark when the titanium screws soon began to be manufactured. By the year 1965, the first dental implant patient got the titanium screw implanted in the lower jaw when the field of dental implantology officially began.
Other materials that were initially discovered, like tantalum, also gained momentum initially to be manufactured for implants but lost pace later after the full-fledged implementation of titanium alloys. Branemark, who originally experimented with tantalum after the observation of osseointegration (because of titanium integration to the bone) in Rabit femurs, switched over to titanium, which began the story of modern-day implants.
Currently, more than 600 different implant companies exist in the UK and Indian markets that cater to the demand-supply of dental needs as per the quality and pricing of dental implants.
What Are the Pros and Cons of Titanium Screw and Zirconia Implants?
Titanium Screw Implants:
The shape of implants has had a similar evolution through history ranging from being bladed to subperiosteal (implants made of metal framework that are placed onto the bone rather than inside the bone) to the screw-shaped titanium implants that were predominantly used till they finally were implemented that way.
Zirconia vs. Titanium Implants:
Histologic results show good bone contact for zirconia and titanium, especially given that zirconia resembles tooth color more and has excellent biocompatibility with bone. But still, the cons of zirconia outweigh the pros for using it as a full-fledged material choice in dental implants. So, look into the pros and cons of zirconia and Titanium implants in this table of comparison.
- Excellent human tissue.
- Low bacterial attraction or adhesion.
- High fracture resistance.
- Good corrosion and wear resistance.
- Excellent aesthetics as it resembles tooth color.
- Over time the material may crack or deteriorate.
- Typically available only as one-piece implants. If the patient needs two-piece implants, then the abutment will have to choose a metal option. Adjusting the height of the implant prosthesis after fitting is difficult in zirconia because any grinding or trimming of the surface can weaken the fracture resistance.
- Zirconia implants have excellent biocompatibility in the patient’s mouth irrespective of the autoimmune conditions a patient might be having.
- No reported allergy to zirconia implants.
- Zirconia implants hence are biocompatible, inert, and non-resorbable metal oxides that have superior mechanical properties over ceramic materials.
- Higher failure rates compared to titanium.
In fact, studies also suggest those surface modifications physically and chemically also make them more stable in integrating with the bone, just like titanium implants. But due to commercial usage of titanium from the last few decades and a reported increase in the implant failure rates (on experimentation with zirconia as an alternate prosthesis and its disadvantage of material deterioration with time) has led to zirconia not being used for mainstream implant manufacturing purposes. However, the promising results for zirconium definitely give scope for its application in future dental implant prosthetics.
- Excellent human tissue compatibility.
- Comparatively higher bacterial adhesion (requires proper oral hygiene).
- High fracture resistance.
- High corrosion and wear resistance.
- Moderate aesthetics as it does not resemble the tooth color.
- The material remains strong as it does not deteriorate over time.
- Available as two-piece implants that are really beneficial in cases of angled implants for proper alignment and positioning. After the prosthesis is fit on top of the titanium implant, it can be further adjusted and trimmed to suit the patient’s occlusion (bite) without weakening the fracture resistance of the prosthesis.
- In patients with certain autoimmune conditions like Crohn’s disease, diabetes, or rheumatoid arthritis -the metal ions released from the titanium implant can cause localized inflammation and irritation, according to research by some toxicologists. Allergies would be reported in patients with a history of metal allergies.
- Lower failure rate and most preferred material of choice for implant manufacturing.
To conclude, discussing the material of choice for dental implants with your dental surgeon is a good decision. However, titanium continues to be the present material of choice after a long evolution of materials in implant dentistry. To increase the lifespan of your dental implants, it is pivotal to maintain oral hygiene, avoid smoking and periodically visit your dental surgeon or implantologist for best results.