Lucius Cornelius Sulla Felix was dictator of Rome from late 82 - 79 BC, however not in the sense of the original meaning of 'dictator':
William Smith, D.C.L., LL.D.: A Dictionary of Greek and Roman Antiquities, John Murray, London, 1875. (Smith's Dictionary) explains at length:
DICTAʹTOR, an extraordinary magistrate at Rome. The name is of Latin origin, and the office probably existed in many Latin towns before it was introduced into Rome (Dionys. v.74). We find it in Lanuvium even in very late times (Cic. pro Mil. 10). At Rome this magistrate was originally called magister populi and not dictator, and in the sacred books he was always designated by the former name down to the latest times (Cic. de Rep. i.40, de Leg. iii.3, de Fin. iii.22; Var. L.L. v.82, ed Müller; Festus, s.v. optima lex, p198, ed. Müller).