Introduction
We developed and commercialized a bite block (Bite Guard®) which is intended to protect the tongue, lip and teeth in collaboration with a local company. The major characteristics are as follows;
1.The shape and silicone-based material can withstand chewing pressure.
2.The brim protects the tongue against biting by teeth.
3.The thickness and hardness prevent tracheal tube deformity due to chewing force.
 We compared the new bite block (Bite Guard group, n=25) for protection of teeth and soft tissue and the conventional bite block (conventional group, n=25). Approval for this study was obtained from the Ethics committee in Hamamatsu University School of Medicine.

Method
We conducted a research with patients scheduled for surgery in the spine position. Questionnaires were given to anesthesiologists in charge. Either type of bite block was inserted after intubation, removed after extubation. We evaluated ease of insertion, protective performance of the teeth and soft tissue, stability, and protective performance of tracheal tube.

result
The anesthsiologists inserted in all cases of Bite Guard groupe, but did not insert in 5 cases of conventional groupe due to loose teeth.
Ease of insertion was similar in both groups, although Bite Guard is bigger than conventional bite block. There was no damage in all cases of Bite Guard groupe, while bleeding from the soft tissue was observed in 3 cases of conventional groupe. There was no deviation at extubation except for one case in which the usage was mistaken in Bite Guard group. It was necessary to hold the bite block by hand at extubation so as not to be displaced in conventional groupe, still there was deviation in some cases. Protective performance of tracheal tube was equivalent in both groupe.

Conclusion
Bite Guard has similar ease of insertion, greater stability, and a potentially better protective effect for soft tissue, compared with conventional bite blocks.



08 / Comparison of a conventional bite block with a new type bite block which is intended to protect the tongue, lip, and teeth