Solid Snake provided your answer....
There are temperature probes you can leave in the meat during cooking. They are very clear about that in the packaging. If there is any doubt, then consider it a thermometer which cannot be left in the oven.
I found that my "leave in" probe was far less accurate at reading temperature than my cheap, stab it when it's out of the oven, meat thermometer. I always check my temperature at set times during cooking rather than relying on a probe.
Of course, you might be much wealthier than I am (you get to have lamb!!!) so maybe you can afford a really good probe.