Officers are renewing their appeal for information on the 10th anniversary of the disappearance of Charlene Downes.
They believe she was one of a number of girls who were groomed for sex by men.
An investigation by The Times found police initially drew up a list of 100 "people of interest" due to the number of adults thought to be abusing her.
Lancashire Police said others affected by abuse would now be adults and might be more willing to share information.
Police also hope the publicity surrounding recent "high profile" grooming cases will encourage new witnesses to speak to them.
Charlene's body has never been found and no-one has been convicted of killing her.
At a retrial in 2008 a man was cleared of her murder, and another man was found not guilty of helping to dispose of the teenager's body.
Four years after Charlene's disappearance another Blackpool girl, 15-year-old Paige Chivers, went missing. She is also presumed to have been murdered.
Officers said the two cases were not directly connected, but said there were similarities.
Charlene's mother, Karen Downes, said: "I'm still as devastated as I was 10 years ago, and I still live in hope that one day she will be found.
"I will never give up until justice is done for her, and I'm very disappointed that nothing has been done by now."
She added: "I want the police to do more, they have done nothing in the past five years since the case collapsed, they have just brushed it under the carpet or put it in a dusty cupboard somewhere."
Assistant Chief Constable Andy Rhodes said: "Charlene was involved in a situation in Blackpool around child sexual exploitation, and her disappearance is linked to that problem in Blackpool at the time.
"We think there are people out there that know things and have never come forward.
"We also think there are people out there, who were children involved in that scene at the time, who may now have the confidence to come forward."
He added: "We are not connecting the murders [of Charlene and Paige] directly, but they were obviously in the same area and the same scene in terms of child sexual exploitation, so we think there's significant amounts of consistencies in terms of how these tragic murders occurred."
Police investigating the murder of a Blackpool 14-year-old say they hope people who have never come forward might now have the confidence to do so.