As mobility service dogs use their teeth to pick up fallen objects, pull wheelchairs and open refrigerator doors, it is often found that the transitory load is placed on their teeth, jaw bone and TMJ, etc. So, We experimentally measured the bending strength of the teeth taken from a beagle used in another experiment. The bending strength of the beagle canine tooth was 176.7MPa for the crown, 152.4MPa for the cervical part, 174.4MPa for the radicular part, with the average being 167.9MPa. Converting the measured values to Newtons (N) gives 3468.0N for the crown, 5212.3N for the cervical part and 5608.5N for the radicular part. When pulling a wheelchair with a 60kg person from the road to the pavement, the necessary strength is about 260~500N (26.5~51kgf), so it is discovered that the extent of the load for pulling a wheelchair does not fracture canine teeth. It is inferable that large dogs need much load on their teeth to be fractured.
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