Why, all of the sudden, is my dog doing this?

My dog is 10 years old, and we always have done a good job keeping up with her dental care (brush 2-3 times per week). All of the sudden, she is starting to chew through wires throughout the house. Luckily, she has not chewed through any 'Live wires', but I am afraid she will do that. What would cause a dog to start doing this at 10 years old? Thanks.
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Does your dog like to chew? Maybe she just happened to try one and he really liked it... every dog's got their own preferences - mine likes to chew on my mechanical pencils. Or she might be starting to go senile. Or maybe there's something that is bothering her that is causing her to chew - she's anxious, she's bored or something feels funny in her mouth... In any case, have you tried giving her a rawhide, nylabone and some other chew toys? If you can find something she likes better, she might leave the wires alone. Also buy some "bitter apple" spray and use it on all the wires that she can reach.
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