Osteogenese nach Laserosteotomie mit einem CO2-Laser im Vergleich zur Osteotomie mit konventioneller Sägetechnik - eine tierexperimentelle Studie

Laser osteotomy has several potential advantages in comparison to
classical bone incision by mechanical saws. In previous studies the
bone healing was delayed due to the damage of the thermal effects
compared to mechanical instruments like the bone saw. With 7
Beagles as an experimental model, a comparative study was done to
assess the healing of bone in response to osteotomy by a new
modified carbon dioxide laser system and a mechanical bone saw.
Using sterile technique, an approximately 6 mm deep incision was
made in the ventral aspect of both mandibles with each method.
During the follow-up period three intravital stains were injected
to mark the surface of new-bone growth. After the dogs were killed
22 days following the surgical procedure the tissue response was
examined by polychrome sequential labelling and undecalicfied
paragon-stained ground sections. The sawed mandibles demonstrated a
retarded rate of healing and a persistent superficial defect at the
impact site. The results of the laser group were quite different.
Some of the specimen showed a similar delay in bone healing like in
the saw group. In some cases a large layer of carbonised debris was
recognized. This retarded healing was most likely due to a surface
deposit of charred tissue elements, produced by the thermal effects
of the laser. In a third group of laser specimen showed a complete
reconstruction of the incision by new Haversian bone and no signs
of any damage by thermal effects due to the laser application. This
modified carbon dioxide laser appears to be an effective and
precise bone ablator. According to the results of previous studies
the appearance of carbonisation could be prevented in some cases.
If the key is found to reduce the risk of carbonisation to the
maximum the future is open for the laser in orthopaedic surgery.