Studies have shown that this risk exists with both needles and cannulas, but it's very rare for both. The chances of it happening with needles are about 1 in 6410 injections, and for cannulas, it's even lower, about 1 in 40,882 injections. Also, more experienced practitioners, those who have been injecting for over five years, had a 70.7% lower chance of causing an occlusion. Moreover, the more frequently a practitioner performs injections, the slightly lower the risk becomes, with a 1% decrease in odds for each additional injection performed per week.
It's worth noting that most occlusions didn't lead to long-term problems, with 85% of them having no lasting effects. While it's clear that needles might present a slightly higher risk for occlusion compared to cannulas, the precision they offer for the placement of fillers can be a significant advantage, especially in the hands of an experienced doctor. I feel the minimal risk associated with needles might be outweighed by the greater control they offer over the procedure.
