A

B

C

D

There is a right floor of mouth fluid collection as shown on images A and B. There are numerous dental caries and periapical lucencies throughout but the first and third right mandibular molars are carious (red arrows), have periapical lucensies (green arrow), and are immediately adjacent to the fluid collection (Image C). Image D suggests contiguity of the fluid collection with the carious portion of the third mandibular molar. For odontogenic abscesses like this, do not rely on the presence of rim-enhancement to call an abscess. Abscesses can be small or thin and as such, not show rim enhancement. Any fluid collection next to a carious tooth with periapical lucency should be considered an odontogenic abscess until proven otherwise.