Dimensional changes after immediate implant placement with or without simultaneous regenerative procedures: A systematic review and meta-analysis

Objective To analyse alveolar ridge volume changes after immediate implant placement, with or without a regenerative technique. Methods Studies investigating the effect of immediate implant placement on ridge dimensional changes were identified through an electronic search conducted using MEDLINE (PubMed) and EMBASE. Weighted mean changes (WMC) between baseline and follow-up time were calculated and subgroup analysis was performed according to study design, evaluation method and regenerative strategies. Results After immediate implant placement alone WMC of RCTs showed a loss in width and height of 1.1 mm. After flapless immediate implant placement with immediate provisionalization and a graft WMC showed a loss in width and height of 1.02 mm and 0.79 mm, while after flapped immediate implant placement and a graft WMC showed a gain of 1.79 mm. After immediate implant placement plus a non-resorbable membrane WMC showed a loss in height of 0.07 mm. After immediate implant placement plus a resorbable membrane and a graft WMC showed a gain in height of 1.09 mm. Conclusions Immediate implant placement does not seem to counteract alveolar ridge modelling after tooth extraction. Furthermore, the currently available evidence does not allow for any conclusive statements regarding the efficacy of a concomitant regenerative technique in preventing the amount of alveolar reduction.