Brief Answer: Detailed below. Detailed Answer: Hello! Thank you for the query. I assume that your dog has been rabies vaccinated. Please note that dogs saliva contains lots of bacteria which quite often cause tissues inflammation. Such inflammation can heal really hard. Especially if the teeth has reached muscles or tendons. According to the picture, it does not look bad. So it is a chance that you wont get it more serious. Please be aware of symptoms like swelling, spreading redness, fever, warm hand. If any of this symptoms will appear, you should visit a surgeon. Some incisions might be necessary and antibiotic for sure. To make itchiness less intense, you may try some anti inflammatory cream containing Ketoprofen. Try to keep your arm little bit higher so the swelling can go away. Hope this will help. Feel free to ask further questions. Regards.

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