**2. Materials and Methods**

A literature search was performed in electronic databases, including PubMed, Medline, OVID, and Web of Science, by using the following keywords: "membranes", "guided bone regeneration", "guided tissue regeneration", "coated", and "coating" from 2017 January to 2022 June. Documents written in English were selected. Sixty-two papers were found and among them, a total of 41 papers were included in this study, excluding 21 papers not related to coated membranes or review papers (Figure 1). Based on the selected 41 papers, we would like to briefly review the membrane coating materials studied so far (Table 1).

**Table 1.** Summary of included studies on coated barrier membranes.



**Table 1.** *Cont*.

Abbreviation: SA, sodium alginate hydrogel composite; Mg, magnesium; Ti, titanium; PTFE, polytetrafluoroethylene; PP, polypropylene; CaP, calcium phosphate; HA, hydroxyapatite; TCP, β-tricalcium phosphate; SiO2, silicon dioxide; PRF, platelet-rich fibrin; EMD, enamel matrix derivative; AMTN, amelotin; HyA, hyaluronic acid; CHX, chlorhexidine; AMPs, antimicrobial peptides; FN-silk, recombinant spider silk protein functionalized with a cell-binding motif from fibronectin; EGCG, epigallocatechin-3-gallate; II, ion implantation; PVD, physical vaper deposition; APP, atmospheric pressure plasma treatment.

**Figure 1.** This is the flow chart of this study.
