BackgroundThe most efficient methods used for molar intrusion in the treatment of anterior open bite is a well-established conflict in the field of orthodontics. Searching the current orthodontic literature resulted in a controversial methods regarding the treatment of anterior open bite, so the question remains unanswered.ObjectiveTo perform a systematic review to evaluate the effectiveness of different molar intrusion methods used in the treatment of anterior open bite patients, to explore the changes that occur in the vertical facial morphology and mandibular rotation.Search StrategyElectronic databases were searched up to April, 2016 in (CENTRAL-Cochrane register of controlled trials, PubMed and LILACS). Grey literature was also searched electronically through Google Scholar. Hand searching was done in the central library in Cairo University and the Cairo Dental Journal (CDJ) as well as high impact factor journals in the field (AJODO, EJO and The Angle Orthodontist). Email alert for PubMed and Google scholar were set and monitored until June, 2016. Citations of all the included studies were also checked manually for relevance. Language was restricted to English.Selection CriteriaThe following criteria were met for study selection: a randomized controlled human trials, retrospective and prospective cohort studies on the molar intrusion methods used for anterior open bite treatment. While, surgical treatment were excluded. Studies with no comparative group were not takenResultsTwenty articles were eligible for the descriptive analysis, but only 4 were eligible for the quantitative analysis. Quality assessment of the included articles showed moderate to high quality. Meta-analysis using the fixed effect model to evaluate the mean difference (MD) with level of significance set at P≤0.05 was performed to compare the effect of Frankel-4 appliance versus control group on overbite and it showed that a significant improvement of overbite in Frankel-4 appliance group about 2 mm greater than the control group. Also, meta analysis had obtained to compare the effect of Frankel-4 appliance versus control in changes of Mandibular Plane Angle and it showed that there was no significant difference between the two interventions. Another meta analysis had obtained to compare the effect of Frankel-4 appliance versus control on maxillary molar intrusion and it showed that there was no significant difference between the two interventions. Meta analysis compared the effect of Magnetic PBB versus Spring PBB on maxillary molar intrusion and it showed a significant maxillary molar intrusion about 0.6 mm in the Magnetic PBB group greater than the Spring PBB group. Meta analysis compared the effect of Magnetic PBB versus Spring PBB on overbite and it showed a significant improvement of overbite about 1 mm in the Magnetic PBB group greater than the Spring PBB group.ConclusionBased on the limitation of our review on the most efficienct molar intrusion methods in the treatment of anterior open bite, it was concluded that:•A significant improvement in overbite was found in Frankel-4 appliance group about 2 mm greater than the control group.•No significant difference was found regarding to changes in the mandibular plane angle or maxillary molar intrusion between Frankel-4 appliance group and control group.•A significant improvement in overbite was found in MPBB group about 1 mm greater than the SPBB group.•A significant maxillary molar intrusion was found in Magnetic PBB group about 0.6 mm greater than the Spring PBB group.•There is no enough evidence in the orthodontic literature regarding to the most efficient molar intrusion method used for anterior open bite treatment in adults.