However , variability was substantial .
Restoration type , material s , the patient , the operator , the practice environment and type of care system appeared to influence longevity .
Objective To conduct a systematic review of the literature on the longevity of routine dental restorations in permanent posterior teeth , and to identify and examine factors influencing its variability .
The management of occlusal caries in permanent molars. A 5-year clinical trial comparing a minimal composite with an amalgam restoration
A clinical trial comparing the efficacy of an  occlusal amalgam restoration with a minimal composite restoration and fissure sealant in the management of occlusal caries in young patients has been performed . One hundred and fifty pairs of restorations were placed in 103 patients and assessed during the 5-year follow-up period . Nineteen restorations failed during this period : 11 amalgam and 8 minimal composite . There was some deterioration in anatomical form and marginal integrity of the remaining amalgam restorations . Of the remaining minimal composites , seven suffered clinical ly detectable wear and a further five had some marginal staining . Forty-nine of the minimal composites needed to have repairs to the fissure sealant . The amalgam restorations occupied , on average , 25 % of the occlusal surface of the tooth , compared with 5 % for the minimal composite resin . The results after a 5-year follow-up showed no significant difference in median survival times between the amalgam and the minimal composite
However , variability was substantial .
Restoration type , material s , the patient , the operator , the practice environment and type of care system appeared to influence longevity .
Objective To conduct a systematic review of the literature on the longevity of routine dental restorations in permanent posterior teeth , and to identify and examine factors influencing its variability .