When it comes to microneedling, whether it's being done with a derma roller, derma stamp or derma pen, the length of the needle and the material of the needle is very important.
Which Needle Length Is Best?
This really depends on the area you are treating and your goals. For example, if you are microneedling to diminish wrinkles on your face, then a shorter needle length (perhaps 0.5mm) would be best. But, if you are microneedling stretch marks on your body, then a length of 2 - 3mm would be more suitable.
Below is a rough guide on needle lengths for common skin conditions:
Wrinkles: 0.3 - 0.5mm
Fine lines: 0.3 - 0.5mm
Large pores: 0.3 - 0.5mm
Acne scars: 0.5 - 1mm
Pigmentation issues: 0.3 - 0.75mm
Scars: 1 - 2.5mm
Stretch marks: 2 - 3mm
Burns: 1 - 2.5mm
Sagging skin: 2 - 3mm
Hair loss: 0.5 -1mm
To Help With the Absorption of Topical Creams, Liquids…
It's really only necessary to break the skin barrier if you are microneedling for this purpose. Therefore, a 0.2 - 0.3mm needle length should suffice.
Stainless Steel or Titanium: Which Material Is Best?
This comes down to personal preference, but we recommend titanium. Stainless steel is inherently more sterile, and the needles also tend to be sharper (to begin with at least). However, titanium is far more durable. We do not believe that sterility should be an issue, as you should be disinfecting before and after every use. Therefore, it comes down to sharpness vs durability.
When it comes to microneedling, we believe that durability is more important for most people. It's better to be able to use decently sharp titanium needles multiple times than it is to use very sharp stainless needles perhaps two or three times. The extra sharpness that stainless provides is not really necessary, and you will need to replace your device frequently, which is costly. If you don't replace it, then you run the risk of using stainless needles which have become blunt (and this will cause tears in your skin).
However, if the cost of frequently replacing your unit is not an issue, then feel free to go with stainless steel.