ABSTRACT
AIM: This study was performed to assess the clinical and radiographic success rates of a formocresol and zinc oxide eugenol (ZOE) primary molar root canal therapy (RCT) technique. The effects of this treatment on the permanent successors and on exfoliation times were also investigated. MATERIALS AND METHODS: Study design: the retrospective study included 161 patients with 211 primary molars treated by RCT by a single operator in a private paediatric dental office in the Toronto area. Data were coded and entered into a Microsoft Excel database and analysis undertaken using SPSS software. Predominantly non-parametric tests were used to evaluate statistical differences (p < 0.05). RESULTS: A clinical success rate of 90% (190/211) and a radiographic success rate of 77.3% (136/176) were obtained. Following RCT in a primary molar, enamel defects were found in 6.8% (7/103) of premolars, all of which occurred in first premolars, and in patients treated at a mean age of 54.1 months (p < 0.005). Treated molars exfoliated on average 7.6 months sooner than contralateral teeth (p < 0.005). CONCLUSION: This formocresol and ZOE RCT is a viable treatment for necrotic primary molars and yielded very high clinical and acceptable radiographic success rates.
Subject(s)
Molar/surgery , Root Canal Therapy/methods , Tooth, Nonvital/surgery , Child , Child, Preschool , Female , Formocresols/therapeutic use , Humans , Male , Molar/diagnostic imaging , Retrospective Studies , Tooth, Deciduous/diagnostic imaging , Tooth, Deciduous/surgery , Tooth, Nonvital/diagnostic imaging , Treatment Outcome , Zinc Oxide-Eugenol Cement/therapeutic useABSTRACT
Deep-sea drilling in the Southern Ocean south of Australia and New Zealand shows that the Circum-Antarctic Current developed about 30 million years ago in the middle to late Oligocene when final separation occurred between Antarctica and the continental South Tasman Rise. Australia had commenced drifting northward from Antarctica 20 million years before this.