Diet-induced Obesity Negatively Influences on Periapical Periodontitis

Objectives: Periapical periodontitis (PP) is an inflammation caused by endodontic infection. Metabolic disorders have been interpreted as a low-grade systemic inflammation and may interact with PP. Although endodontic infection deteriorates high-fat diet-induced non-alcoholic steatohepatitis (NASH; J Gastroenterol 48:1259–1270), the effect of diet-induce obesity (DIO) on PP was not well-characterized. This study was designed to examine the influence of DIO on the development of PP.
Methods: Age-matched male DIO B6 and control lean mice (18 weeks of age) were purchased from Taconic Biosciences and subjected to pulpal infection in mandibular first molars. The effect of DIO and infection on body composition, NASH, periapical bone destruction and inflammation was examined by NMR (Bruker Minispec LF 90II), microCT (Scanco mCT100) and histology on days 21 and 42 post infection. DIO and control mice were respectively fed 60% high-fat diet and 14% fat diet during the observation periods.
Results: The average body-fat percentage (BFP) reached plateau by day 21 in both DIO (48%; n=7) and controls (18%; n=5) (p<0.05). The level of NASH was progressively elevated in DIO mice during 42 days observation while NASH was imperceptible in controls. Although the average of periapical lesion size was similar in both DIO and control mice on day 21, DIO mice (n=6) exhibited considerably larger lesions with more irregular bone surface vs. controls (n=5) on day 42 (p<0.05). Histological appearance of periapical lesions in DIO mice were more fibrotic vs. controls on day 21. The fibrotic lesions further progressed until day 42, accompanied with persistent inflammatory cell infiltration. Our data strongly suggest the existence of a pathway/mechanism by which DIO influences PP.
Conclusions: Diet-induce obesity negatively influences on the development of periapical periodontitis.