Evolution and prognosis of necrotic primary teeth after pulpectomy.

To study the evolution of 308 necrotic primary teeth after pulpectomy technique with resorbable paste (Kri-1 + calcium hydroxide + metacresol-formaldehyde) after 30 months. 134 children between 2-9 years were included, among which they had 348 pulpectomized teeth. Out of these 348 teeth, 308 had necrotic pulp and were included in the study. The filling material consisted of a paste based on Walkhoff's master formula and consisted of the combination of Kri-1a (80.8% iodoform, 2.025% parachlorophenol, 1.215% menthol, 4.68% camphor and excipient 15 mg), pure calcium hydroxide and metacresol formaldehyde (metacresol 20 mg, formaldehyde 20 mg, eugenol 20 mg, eucalyptus 6 mg and excipient 40 mg). Root canal filling was performed in one session by one operator. Pain, swelling, and fistula resolution was observed in most cases at the first recall. Progressive remission of radiolucent areas was also observed. A relationship between fistula and radiolucency in pre-treated furcation area was observed, and, in some cases, premature eruption of permanent teeth was recorded. Only two cases out of 308 treated teeth required extraction.