Table 1.

The focus question development according to the PICOS study design

Component	Description
Problem (P)	Bone resorption after tooth extraction
Intervention (I)	Filling alveolar socket with regenerative biomaterial
Comparison (C)	Comparison between efficiency of different biomaterials
Outcome (O)	Different dimensional changes of alveolar bone
Study design (S)	Random controlled trial
Focus question	What biomaterials in combination with stem cells and growth factors are used for socket preservation after the tooth extraction and which of those show the best results regarding alveolar dimensional changes and quality of newly formed bone?