Evaluation of frequent reasons of failure and survival rate of amalgam restorations in 6-12- years -old children in Dental health center of Zanjan in (2010-2012)

Clinical Longevity is a primary concern when selecting a restorative dental material. The aim of this clinical study was to evaluate the frequent reasons of failure and survival rate of amalgam restorations in 6-12- years -old children in Dental health center of Zanjan in 2010-2012. This analytic – descriptive, cross sectional study was performed on 200 patients previously treated at Shafieh dental clinic (in 2010) who were summoned for reexamination of treated teeth. All participants (296 restorations) were reexamined by one examiner with direct Observation, probing by explorer, dental floss and radiography. Data were analyzed using Chi square test. (p 0/05). 52.4% of deciduous teeth (DRT) and 10.5% of permanent teeth (PRT) were failed. In both deciduous and permanent teeth, the most common reason of amalgam restoration failure was secondary caries. Other common reasons of failure in DRT were secondary caries (25.8%), tooth fracture 10.5%), amalgam marginal fracture (7.4%), and amalgam bulk fracture (4.8%) and overhang (3.9%). In PTR secondary carries (7.5%), marginal amalgam fracture (3%) was the frequent reasons for failure. There was no significant difference between two sexes (p>0/05). The failure in DTR was significant higher than PTR (p<0/05) and it was significantly higher in multi surfaces compared to one surface restorations. According to the results of our study, we should emphasize the need for continuing education of dental practitioners and arranging regularly patient’s follow-up.