impacted tooth:
    an unexposed or partially exposed tooth that is so wedged against another tooth, bone, or soft tissue that complete exposure of the tooth is unlikely
implant:
    artificial device replacing tooth root; may anchor an artificial tooth, bridge, or denture
incision and drainage:
    making an incision in an abscess to drain infection
incisors:
    four upper and four lower front teeth, (excludes the canine teeth)
infiltration:
    process for numbing the upper teeth (placing anesthetic liquid under the gum tissue and allowing it to migrate into the bone)
inlay:
    a filling made by a dental laboratory that is cemented into place, generally requires two dental appointments

intraoral camera:

    a tiny TV camera used to view tissues of the mouth (owned by approximately 50 percent of U S dentists