TY  - RPRT
TI  - Method for insuring parallelism of implants placed simultaneously with maxillary sinus bone grafts.
AU  - M S Block
AU  - J S Widner
PY  - 1991
DO  - 10.1016/0278-2391(91)90389-4
UR  - https://pubmed.ncbi.nlm.nih.gov/1848613/
ID  - 1848613
ER  -