Complex sentence: Many approaches had been made to the Foundation over the years by companies wishing to accredit oral hygiene products and indeed the archives show a talk at the 1975 AGM by Dr William Brown from Iowa on -'Endorsement of Dental Products-Yes or No?'.
Split into simpler sentences: Many approaches had been made to the Foundation over the years by companies wishing to accredit oral hygiene products. One of these included a talk at the 1975 AGM by Dr William Brown from Iowa on -'Endorsement of Dental Products-Yes or No?'.