Both Enterprise and the novel Sarek suggest the bond is on a mental level.
Of course it is. Spock and T'Pring were telepathically bonded at age 7, and pon farr occurred when they were both physically mature. Yes, Spock was physically mature long before. But there is an essay in one of the Best of Trek books that lays it out quite logically (
) that T'Pring, as a full Vulcan, ages more slowly and therefore could take a decade or two longer than Spock to become fully mature both physically and mentally, and be able to handle the mental and physical stresses of pon farr.
All canon tells us is that Spock was married to somebody
in the 24th century, as Picard attended the wedding.