The Science of Prosthetic Dentistry
Prosthetic dentistry has been with us for 4000 years; from bamboo pegs to ivory, precious metals and porcelain the search has been on for aesthetic looking materials that stand the test of time. Modern dentistry is big business and people pay thousands of pounds to have ‘perfect teeth’ and above all confidence when they smile.
There is also an expectation that their expensive dental work will last for many years if not a lifetime. There can however be problems!
Most dental implants utilise a titanium screw which is inserted into the bone to support the replacement tooth. Approximately 50% of the implants that fail do so due to Peri-implantitis – an inflammation around the implant that results in loss of surrounding bone. Finding a solution to this problem will save the NHS, and dentists a considerable amount of time and money, and importantly improve long term patient satisfaction.
Innovative Materials Research
PhD student, Ali Marie working with Professor David Wood and Dr Thuy Do from the School of Dentistry at the University of Leeds is using Hydrothermal Synthesis to help develop a coating for Titanium Implants that will act as an antimicrobial agent and assist bone regeneration. Hydrothermal Synthesis utilises the high water temperature and pressure of an autoclave to turn soluble minerals into crystalline form. In this particular case producing ordered Fluorapatite crystals which are known to be antibacterial against pathogens implicated in Peri-implantitis. The physical properties of the crystals also improve osteoinductive performance encouraging bone growth right up to the implant.
The unique 10 hour Astell Benchtop autoclave
To produce the optimum Fluorapatite crystals through Hydrothermal Synthesis the autoclave has to operate at a temperature of 121 degrees at a pressure of 2 atmospheres for up to 10 hours! Autoclaves typically run for 20 to 90 minutes so it was clear that an off the shelf model would not be suitable.
Following consultation and site visits from Astell’s Jonathan Pass, a commitment was made to build a unique benchtop autoclave, programmable with extended cycles of up to 10 hours. Furthermore, to guarantee the autoclave was robust enough to cope with the longer cycles, components and door seals were upgraded for extra durability. Ali Marie was delighted: ‘Astell have given me a unique benchtop autoclave, one modified specially for my work. It is fully programmable and I can run different timed Hydrothermal Synthesis cycles up to a maximum of 10 hours. It’s small size also means it takes up little space on the benchtop – perfect for our laboratory in St James’s University Hospital.’
Jonathan Pass was pleased to help: ’It has been great working closely with the School of Dentistry and delivering a bespoke solution that will help them with their important dental research for many years to come. I believe it also demonstrates our commitment to do whatever it takes to deliver innovative technological products to meet our customers’ needs.
Crucial role of the autoclave
The autoclave has traditionally played a backroom role in laboratories and clinical environments. The development of a bespoke model for extended cycle Hydrothermal Synthesis demonstrates how the humble autoclave can be adapted to make a crucial difference to the speed, quality and accuracy of important research.
The Benchtop autoclave supplied to the School of Dentistry is a 33 liter Ecofill model
- A fully programmable touch screen controller
- An electropolished stainless steel chamber
- Small footprint
- Integral water reservoir
- An ultra-quick door lock mechanism
- A pulsed-heat drying system, which is adjustable in 5 minute steps