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WHAT IS A DENTAL IMPLANT? Dental implant is an artificial titanium fixture (similar to those used in orthopedics) which is placed surgically into the jaw bone to substitute for a missing tooth and its root(s). Alternative Solutions Partial and Full Dentures Crowns Bridges History of Dental Implants In 1952, Professor Per-Ingvar Branemark, a Swedish surgeon, while conducting research into the healing patterns of bone tissue, accidentally discovered that when pure titanium comes into direct contact with the living bone tissue, the two literally grow together to form a permanent biological adhesion. He named this phenomenon "osseointegration". Biocompatibility of Material Desired Mechanical Properties High yield strength Modulus close to that of bone’s Built-in margin of safety: Changes in environment around implant Surfaces Composition Ion release Surface modifications Metallic Implant Surface Problem: Implant surface change with time due to oxidation, precipitation… Possible solutions: Oxide layers ( minimize ion release) Prosthetic component from noble alloys Phase stabilizers other than Al & V (eg. Ti-13Nb13Zr, Ti-15Mo-2.8Nb ) Surface Modifications Types of Implants Screw Implants (Left to Right: TPS screw, Ledermann screw, Branemark screw, ITI Bonefit screw) Cylinder Implants (Left to Right: IMZ, Integral, Frialit-1 step-cylinder, Frialit-2 step-cylinder) Procedure First Surgical Phase (Implant Placement) Under Local anesthetic the dentist places dental implants into the jaw bone with a very precise surgical procedure. The implant remains covered by gum tissue while fusing to the jaw bone. Second Surgical Phase (Implant Uncovery) After approximately six months of healing. Under local anesthetic, the implant root is exposed and a healing post is placed over top of it so that the gum tissue heals around the post. Prosthetic Phase (Teeth) Once the gums have healed, an implant crown is fabricated and screwed down to the implant. Cost Wide variability in costs Single implant costs anywhere from $500 - $6000 Average ~ $1250 - $5000 $80,000 for full mouth reconstruction Market Nobel Biocare currently the leader US market grows ~ 20% annually, though it has historically been weak Growing Dental Market Potential Market Size: 10% over 18 missing a tooth1 69% of those aged 3544 missing at least 1 tooth 2% of market penetration2 10% of worldwide dental market3 US market for implants is growing ~20% annually 1. US Department of Health 2. www.3implant.com 3. http://investor.nobelbiocare.com/phoenix.zhtml?c=139018 &p=irol-dental Surface modification for metallic implants Passivation Ion implantation Texturing This work was supported by grants from University of Ferrara, Italy (F.C.), Fondazione CARIFE (F.C.), Guya-bioscience, Ferrara, Italy (F.P.), Fondazione CARISBO (F.P.), Finalized Project ‘‘Materials Tailored for Advanced Technologies’’, National Research Council (C.N.R.), Rome, Italy (A.P.), and Ministry of Education, University and Research (M.I.U.R.), Rome, Italy (A.P.). Contract grant sponsors: Unife 60%; CARIFE; CARISBO; Guya-Bioscience (Ferrara, ITALY) Acknowledgements: This work was supported by grants from Unife 60%(F.C.) and Guya-bioscience (F.P.). Osseointegration (A) Hematoma occurs near screw threads (B) After 3 weeks – Osteoblasts begin forming spongy bone (C) After 4 months – spongy bone replaced by compact bone Lamellar bone – strongest type of bone, most desired next to implant (D) Osseointegration failure Endorsing an intuition of a potential future successful application on mankinds, it was started a trial on rabbits using Biolok titanium dental implants, previously treated to obtain a surface coating with nanocrystalline film of metallic dioxide. Three groups of dental implants has been manufactured and surgically inserted in rabbits tibia: 1. uncoated dental implants (control); 2. TiO2 surface coated dental implants; 3. ZrO2 surface coated dental implants. After thirty days bone sections have been analyzed in correspondance of the contact bone-implant zone and different osseointegration rates have been evaluated among the three groups above. The difference has been based on the presence of marks identifying small bone trabeculae. The results concerning osseointegration were extremely interesting: while in the cortical portion there are no differences among the three types of implants, around the implants embedded in the medullary portion, clearly appeared outstanding new bone apposition around TiO2 coated implants (55%) and ZrO2 coated implants (43%) if compared to the results obtained by uncoated implants (31%). Medullary portion in endosseous uncoated dental implant section. new bone apposition = 31% Medullary portion in endosseous TiO2 coated dental implant section new bone apposition = 55% Medullary portion in endosseous ZrO2 coated dental implant section new bone apposition = 43% Anatase surface nanoscopic topography (300 x 300 nm), produced according to the patented method . Electronic Microscope zoom on zirconium dioxide coated surface