The research group led by Oliver Scholz, at Fraunhofer Institute for Biomedical Engineering (IBMT) at St Ingbert, Germany, says that the new drug dosing system, dubbed Intellidrug, can be used to administer the correct dosage of medication continuously for weeks.
The positive effect of continuous medication is that the drug delivery does not lead to an initial peak concentration, with a gradual tail-off, as is often the case with pills.
The prosthesis itself is small enough to fit into two fake molars, where it is easily accessed and serviced every few weeks. Scholz suggests that the patient could easily have an empty prosthesis swapped for a refill and also have the battery replaced, if need be.
"The dental prosthesis consists of a drug-filled reservoir, a valve, two sensors and several electronic components," said Scholz.
"Saliva enters the reservoir via a membrane, dissolves part of the solid drug and flows through a small duct into the mouth cavity, where it is absorbed by the mucous membranes in the patient's cheeks."
The two sensors monitor the amount of medication that is released. One measures the volume of liquid that enters the mouth, while the second measures the concentration of the medication in the liquid.
The electric circuit opens or closes the duct valve to control dosage, depending on the results of the measurements. Another function is that the circuit will alert the patient, through a remote control, when the medication has run out.
The prosthesis could particularly helpful for dosing patients who are chronically ill, or who find it difficult to adhere to dosage regimens, for example those suffering from dementia or drug addicts.
Intellidrug is scheduled to enter clinical research during 2007 and will initially be tested as a delivery vehicle for naltrexone, a drug that helps opioid addicts to abstain.
The group said it will present the a prototype of the prosthesis at Medtec trade fair in Stuttgart, Germany, 27 February - 1 March. Intellidrug was developed with the help of a research grant under the European Commission's sixth framework (FP6) programme.