BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

252 Roberto Lopez et al.
scale (or greys) shows the different intensities. The intensity of the infrared
radiation depends on the temperature and on the surface characteristics of the
object, the color and the kind of material. Thermographic cameras give a value
of the temperature for every single point, without taking into account that, for
the same temperature, two different materials can emit infrared energy with
very different intensities.
With this new tool we will be able to determine the local heating
experienced by the bone during the process of cutting (drilling) for dental
implants. This way, we can see, frame by frame, the evolution of the
temperature in every single point in the area of study, so every frame
corresponds to a thermography with the data of the temperatures of every single
point of the image. With this data we can study data from heating and cooling
patterns, zone and/or specific peaks and lows.
2. State of the Art
Due to the drilling process, the bone tissue heats up and if the temperature
around the drilling area exceeds the critical limit of 50 ºC, could result in
thermal necrosis, which is the death of the tissue exposed to that high
temperatures. Therefore, the importance of temperature control in this type of
operations results obvious.
Most researchers use conventional temperature measure methods, such as
the placing of thermo couples (A b o u z g i a & J a m e s, 1995), (B a c h u s et al.,
2001), (M a t t e w s et al., 1984). In this way, the temperature record can be
continuous; not on the contact area between the tool and the bone, but in the
gaps set for the thermo couples away from the drilling area.
The measurement of temperature (for example for fever) is very well known
in old and modern medicine. The infrared thermology is a contactless method
for measuring temperature and seems to be very useful in research and everyday
medicine. Everyday there are more and more studies that use thermography for
the measurement of temperature in different process. This way, (W i l d et al.,
2003), determined the temperature in bone drilling for facial human bones for
inplants. They obtain results for temperature peaks although they don´t specify
how they record the thermography at the highest temperature.
Other researchers, like (U d i l j a c k et al., 2007) also use the thermographic
camera to measure the temperature of drilling while using different drill bits.
But neither in this case, nor in other cases like (W i l d et al., 2003), there is a
continuous record of the temperature to be processed. So it is understood that
the evaluation of the highest temperature is done objectively.
The advantages of the infrared thermography in continuous record to
measure the temperature are obvious: