Nine hundred fifty-one emergency and 997 nonemergency patients seeking endodontic treatment were the basis of this study. Variables of interest were 10 pain descriptors, percussion and palpation tests, causative factors, and paired pulpal and periapical diagnoses. A higher number of patients suffering from symptomatic pulpal conditions sought emergency care. Odds of caries being a causative factor were high in symptomatic pulps compared with asymptomatic pulpal and periapical conditions. Higher odds ratios were obtained for sharp pain in symptomatic pulps versus symptomatic periapical conditions. Conversely, odds ratios for dull pain were higher in symptomatic periapical conditions compared with asymptomatic periapical conditions. Percussion and palpation tests were significant in differentially diagnosing between pulpal and periapical conditions. In conclusion, caries was associated with painful pulpitis. The results confirm the differential diagnostic power of sharp and dull pain and percussion and palpation tests. Several symptoms previously believed to have differential diagnostic power were found insignificant.