TABLE 7.

Characteristics of the clinical trials utilizing tissue-engineering strategies for alveolar ridge preservation

Cell-based tissue engineering
Reference	Defect type	Cell type	Origin	Scaffold	Control group	Flap, complete closure
Kaigler et al191	Not reported	Autogenous stem and progenitor cells	Bone marrow from iliac crest	Gelatin sponge (+ collagen membrane)	Gelatin sponge (+ collagen membrane)	Flaps raised, primary closure

Signaling molecule-based tissue engineering
Reference	Defect type	Biologic	Scaffold	Membrane	Control group	Flap, complete closure
Coomes et al160	Buccal bone dehiscence ≥50%	Recombinant human bone morphogenetic protein-2	Collagen sponge	No	Collagen sponge	FlaplFlapless, no primary closure
Fiorellini et al173	Buccal bone dehiscence ≥50%	Recombinant human bone morphogenetic protein-2	Collagen sponge	No	Group 1: collagen sponge Group 2: spontaneous healing	Flaps raised, primary closure
Geurs et al176 and Ntounis et al217	Not reported	Recombinant human platelet-derived growth factor-BB	Freeze-dried bone allograft/β-tricalcium phosphate	No	Group 1: collagen plug Group 2: freeze-dried bone allograft/β-tricalcium phosphate + collagen plug Group 3: freeze-dried bone allograft/β-tricalcium phosphate + platelet-rich plasma + collagen plug	FlaplFlapless, no primary closure
Huh et al183	Teeth to be extracted with <50% alveolar vertical bone loss	Recombinant human bone morphogenetic protein-2	Hydroxyapatite/β-tricalcium phosphate	No	Hydroxyapatite/β-tricalcium phosphate	Not reported, not reported
Jo et al188	Teeth to be extracted with >50% alveolar bone height	Recombinant human bone morphogenetic protein-2	Collagen sponge	Bioabsorbable collagen membrane	No control group	FlapsFlaps raised, no primary closure
		Recombinant human bone morphogenetic protein-2	Hydroxyapatite/β-tricalcium phosphate	Bioabsorbable collagen membrane	No control group
Kim et al196	Residual socket with <50% bone loss	Recombinant human bone morphogenetic protein-2	Demineralized bone matrix gel	Bioabsorbable collagen membrane	Demineralized bone matrix gel	FlapsFlaps raised, no primary closure
Lee and Jeong199	Residual socket with <50% bone loss	Enamel matrix derivative	Demineralized bovine bone matrix	Bioabsorbable collagen membrane	Group 1: demineralized bovine bone matrix + bioabsorbable collagen membrane Group 2: spontaneous healing	FlaplFFlapless, no primary closure
Lee et al200	Buccal bone dehiscence ≥50%	Enamel matrix derivative	Xenogeneic bone mineral containing collagen	Bioabsorbable collagen membrane	Xenogeneic bone mineral containing collagen + bioabsorbable collagen membrane	Flapless, primary closure
McAllister et al208	Not reported	Recombinant human platelet-derived growth factor-BB	Xenogeneic bone mineral containing collagen	No	No control group	Flaps raised, pediculated palatal connective tissue graft used for primary closure
		Recombinant human platelet-derived growth factor-BB	β-Tricβ-Tricalcium phosphate	No	No control group
Mercado et al209	Buccal bone dehiscence ≤1 mm at the time of extraction, no palatal defect	Enamel matrix derivative	Xenogeneic bone mineral containing collagen	No	Xenogeneic bone mineral containing collagen	Flapless, free gingival graft used for primary closure
Nevins et al215	Not reported	Recombinant human platelet-derived growth factor-BB	Xenogeneic bone mineral containing collagen	No	Xenogeneic bone mineral containing collagen	Flaps Flaps raised, primary closure
		Enamel matrix derivative	Xenogeneic bone mineral containing collagen	No	Xenogeneic bone mineral containing collagen
		Enamel matrix derivative	BoneBone ceramic	No	Xenogeneic bone mineral containing collagen
Shim et al237	Not reported	Recombinant human bone morphogenetic protein-2	HydroHydroxyapatite	No	Demineralized bovine bone matrix	FlapsFlaps raised, primary closure