It was the hypothesis of this study that the combined extraoral and intraoral examination indeed confirms the presence of dental problems in guinea pigs, however, commonly it is not possible to localise the lesion and underlying aetiologies. Additionally, an advantage of computed tomography compared to oral examination was assumed.
Therefore, diagnostic imaging, in particular CT, could be an invaluable tool to localise the lesion and the origin of the disease process.
Medical records of guinea pigs presented from 2006 to 2010 at the University of Veterinary Medicine Vienna were reviewed. Animals suspicious for dental disease with an oral examination as well as computed tomography of the head were included in this retrospective study. Guinea pigs were grouped into three categories: the first category (n=51) included animals with dental disease suffering from pain and therefore had a compromised food intake (such as tooth fracture, periapical disease, macrodontia); the second category (n=8) included pathologies that potentially (facultative) cause pain and therefore inappetence or compromised food intake (such as retrograde elongated reserve crowns, otitis media); in the third category (n=7) no reason for inappetence or compromised food intake was found on CT examination.
Statistical analyses were performed to compare results found on clinical extraoral examination (exophthalmos, lower jaw swelling, deviation of the mandible) as well as intraoral examination (oblique worn incisors, spikes, bridges, asymmetric elongated cheek teeth, macrodontia) with category 1 lesions on CT.
Sixty-six guinea pigs met the inclusion criteria of this study, of which 95% showed altered food intake and 49% a reduced body condition score.
As result of the extraoral and intraoral examination some pathologies were detected: asymmetric elongated cheek teeth (n=28), bridge building of lower cheek teeth (n=24), oblique worn incisiors (n=17), lower jaw swelling (n=13), exophthalmos (n=10), and macrodontia of incisors (n=6).
Unilateral exophthalmos was diagnosed in 10 animals of which the majority (80%, p<0.05) showed periapical disease of cheek teeth. Of thirteen guinea pigs with lower jaw swelling 12 (92%) were diagnosed with a category 1 lesion on CT. Periapical disease of incisors (n=11) and cheek teeth (n=32) were most often diagnosed on computed tomography.
All macrodontic abnormal incisors were coincidingly detected by CT and oral examination, however, macrodontic check teeth were only detected by computed tomography. A deviation of the mandible in awake guinea pigs seemed to correlate with pathologies in the cheek teeth region.
In order to fully diagnose and subsequently treat oral pathologies (especially dental disease), a complete oral examination as well as a computed tomography of the head of the guinea pig should be performed.