Hello there, I am DrD
I will try to answer your quetion as much as I can ,
Since your veterinarian looked at his mouth under sedation I assume he would have told you that your dog has a gum/periodontal disease or not .Yes you are correct. Gum and Periodontal tissues around the tooth may get infected and may bleed.
As I said your vet should have noticed that easily and offer you a treatment plan. Again , oral tumors small and large also cause bleeding from the mouth as well as the puncture wounds as you said your dog has at his hard palate. http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=130
Malocclusion is another problemmay cause oral bleeding .
Malocclusion refers to an abnormal tooth alignment. Over bite (parrot mouth, over shot, class two, over jet, mandibular brachygnathism) occurs when the lower jaw is shorter than the upper. There may be a gap between the upper and lower incisors when the mouth is closed. The upper premolars are displaced at least 25% toward the front compared to the lower premolars. An over bite malocclusion is not considered normal in any breed and is a genetic fault. The most commonly affected breeds are those with elongated muzzles (Collies, Shelties, Dachshunds, and Russian Wolfhounds).
An under bite (under shot, reverse scissors bite, prognathism, class III) occurs when the lower teeth protrude in front of the upper jaw teeth. Some short-muzzled breeds (Boxers, English Bull Dogs, Shih-Tzus, and Lhasa Apsos) normally have an under bite, but it is abnormal when it occurs in medium-muzzled breeds. When the upper and lower incisor teeth meet each other edge to edge, the occlusion is considered an even or level bite. Constant contact between upper and lower incisors can cause uneven wear, periodontal disease, and early tooth loss. Level bite is considered normal in some breeds, although it is actually an expression of under bite.
Your best bet would be taking him in for a recheck.Please take your dog to the emergency room If the bleeding does not stop.
I hope this helps.
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