Clinical and histomorphometrical systematic review on alveolar ridge preservation techniques

Alveolar ridge preservation techniques (ARPs) are raising a growing interest among clinicians, but their efficacy and effectiveness are still unclear. The aim of this paper is to systematically review clinical and histomorphometrical data from literature that provide information regarding the effect of alveolar ridge preservation procedures on healing after tooth extraction in humans.

Method:

The MEDLINE-PubMed and the Cochrane CENTRAL databases were searched regarding clinical and histological studies about alveolar ridge preservation techniques on humans. A quality assessment of included studies was performed. Mean values and standard deviation were extracted with regard to dimensional changes in both bone width and height, and histomorphometrical data such as percentage of bone, connective tissue and residual graft material. Different meta-analysis were conducted between different groups of alveolar ridge preservation procedures.

Result:

A relevant heterogeneity between studies was assesed. A statistical significance in maintaining horizontal and vertical bone dimension was found considering studies using a barrier. The best value regarding bone percentages was produced at 3 months by allografts (54,4%) while the worst was obtained at 5 months by xenografts (23,6%); with regard to connective tissue, the highest and lowest values were shown at 7 months, respectively with allografts (67%) and alloplasts (27,1%). Last, referring to residual graft material, the lowest rates were displayed by allografts (12,4% to 21,11%) while using xenografts and alloplasts, at 7 months, the highest were showed (37,14% and 37,23%).

Conclusion:

Alveolar ridge preservation procedures are effective in limiting horizontal and vertical ridge alterations in post-extraction sites. No major histological and histomorphometrical differences arise among different ARPs when compared to spontaneous healing. It seems that the use of barrier membranes alone might improve normal wound healing in extraction sites and that it is unnecessary to wait further than 3-4 months prior to implant insertion.