Figure 4.

Unique metabolites exclusively identified in specific lesion type compared with healthy control. 10-Undecynoic acid value was regarded as one-fold change and employed for the measurement of other metabolites in healthy pulp control. 3-Ethyl-5-(2-ethylbutyl)-octadecane value was regarded as one-fold change and employed for the measurement of other metabolites in periapical abscess. Ethanimidic acid value was regarded as one-fold change and employed for the measurement of other metabolites in radicular cyst, and octanoic acid value was regarded as one-fold and employed as a reference for the measurement of fold change for the other metabolites in periapical granuloma. The data display the fold change of the area under the peak of unique metabolites in each group. The data were analyzed using one-way analysis of variance (ANOVA) using Tukey’s multiple comparisons test. P-value ≤0.05 was considered as significant. (A) Metabolites identified only in healthy control. (B) Metabolites identified only in periapical abscess. (C) Metabolites identified only in periapical cyst. (D) Metabolites identified only in periapical granuloma. * reveals that P-value < 0.05, ** reveals that P-value < 0.01, *** reveals that P-value < 0.001, **** reveals that P-value < 0.0001.