| Objective:To systematically assess the effect of the impacted lower mandibular third molars of different eruption states on the angle fracture and condylar fracture.Methods:PubMed, Web of Knowledge, Cochrane Central Register of Controlled Trial, Science Direct Database, Chinese National Knowledge Infrastructure, Wanfang Database and China Scientific Journal Database were searched from the date of establishment of the databases to November 2014. Cohort studies, case-control studies and randomized controlled studies about the effect of mandibular third molar on the angle fracture or condylar fracture were collected. Two reviewers worked independently to select the eligible studies, extract the data and assess the methodological quality. The Revman5.0 and Stata 11.0 software are adopted to conduct with the data by meta-analysis.Results:A total of 13 studies out of the 581 searched studies were involved in this meta-analysis, all of which were case-control studies. Meta analysis showed that patients with impacted mandibular third molars are 0.54 fold more prone to get a condylar fracture than those without impacted third molars, [(0.38,0.77) P<0.00001]; while patients with mandibular third molar are 1.21 times more likely to have an angle fracture than those without mandibular third molars, [RR=1.2195%CI= (1.10,1.33) P<0.00001]; while patients with impacted mandibular third molar are 2.00 times more likely to have an angle fracture than those without impacted mandibular third molars, [RR=2.00 95%CI= (1.79,2.23) P<0.00001]; patients with impacted mandibular third molar are 10.84 times more likely to have an angle fracture than those without impacted mandibular third molars, [RR=10.8495%CI= (8.79, 13.37) P<0.00001].Conclusion:Impacted mandibular third molars are a dominator factor for mandibular angle or condylar fractures. But based on the low level of current evidence, further design strict, large-scale and high-quality clinical trials are needed to provide more reliable evidence. |
PDF Full Text Request