Will 8 mm long dental implants be long-lasting?

I have no problems with 8mm implant, I place 7mm and 7.5mm regularly. The only thing I’d that you have to have good quality bone to support it.

implant length matters, longar implant is always better. but more important is width of implant. so if bone quantity is good and wider implant is possible thn no issue with 8mm implant. i want to add one more thing is that , short implant means shorter life of implant; or more chances of failure , its not like that.

Provided you have plenty of thickness in the area for an implant, an 8mm long implant will be fine. I wouldn't expect any issues.

As long as the implant is healed meaning integrated, a 8 mm implant will be strong and solid in your bone. Which tooth the implant is replacing can play a factor in how much chewing pressure that implant exerts. There are implants that are 4 mm in depth and are very strong. You’ll be fine as long as the entire 8 mm implant will be in 8 mm of bone.