Prøveforelesning
Bedømmelseskomité
Professor, PhD, Pentti Tengvall
Gøteborgs universitet, Sahlgrenska Academien
Professor, Dr. Odont. Lars Rasmusson
Gøteborgs universitet, Inst. For odontologi
Førsteamanuensis, Dr. Odont. Anne Merete Aass
Universitetet i Oslo, Det odontologiske fakultet
Leder av disputas: Instituttleder Pål Barkvoll
Veileder: Jan Eirik Ellingsen, S. Petter Lyngstadaas og Håvard J. Haugen
Sammendrag
Since 1951 titanium (Ti) has been known as one of the most successful implant materials for dental and orthopaedic restorations, due to its biocompatibility and its ability to withstand high loads.
Today’s dental implants require a healing time of several months before an implant can be loaded with a bridge or a crown.
By modifying the Ti implant surface characteristics, it is possible to achieve a faster, stronger and more predictable implant integration for early loading. In this matter, fluoride-modification of Ti implants by hydrofluoric acid (HF) has shown successful results since 2004. However, it has not been fully understood why. Is it due to a specific surface micro/nano-topography, or maybe to a particular surface chemistry?
The aim of the study has been to treat Ti implants with HF, to characterise the created surface topography and chemistry, and to investigate the effect of these modifications on the bone formation in vitro and in vivo.
HF-modification of Ti surfaces not only induced topographical variations by creating a specific nano-level roughness, but also by implementing fluorine, oxygen and hydrogen ions in these surfaces.
In vitro analysis suggested a lower osteoblast-like cell death, and a higher cell number on the surfaces treated with HF. These surfaces also showed a higher surface roughness.
In vivo, all the HF-modified implants showed higher bone-to-implant attachment strength, an up-regulation of some bone formation markers (collagen-I, osteocalcin), a better inflammatory response (lower TNF-alpha, IL-6, and higher IL-10), and more and faster mineralised peri-implant tissue when compared to controls.
The results collected throughout this study showed that Ti implant surfaces can be modified with HF to produce an optimised topo-chemistry for bone growth and implant osseointegration.