75-stone Arktos at Highland Wildlife Park in Inverness-shire had been suffering with toothache when the dentist was called.
Broken or infected teeth are a major problem for polar bears in the wild. Keepers at the park had trained him to open his huge mouth to show his 42 razor sharp gnashers.
Problems with his teeth showed up after the check up and so the Royal Zoological Society of Scotland's team of veterinarians came to carry out a 3-hour operation.
The dental work had to be carried out in the equivalent of a dentist's chair that was made from scaffolding poles and planks. The team had to anaesthetise Arktos in order to get him into the chair.
Douglas Richardson, animal collection manager at the Highland Wildlife Park, said: "We train our polar bears and other large animals to take part in regular health checks. This means that we can spot issues like this before they become a problem and give our animals the best possible care available.
"Arktos really is a lucky bear and we were delighted to be able to save his tooth. In the wild the infection would have tracked through his system, causing him a great deal of pain and discomfort and, over the longer term, it could eventually kill him."
"Although due to his size an operation like this is never straightforward, the dental work carried out is actually very similar to a root canal that we humans would have - although obviously on a much larger scale."
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