You can online consultation with me on practo app

Yes with pillow

It's best to sleep without pillow when you sleep on your back but when you sleep side lying you can use firm and medium height pillow to balance your head and shoulder height.pillow should not be too height than your shoulder.

I would recommend you to use pillow on side lying. Without pillow when you lie on your sides, either side of your neck will get strain.

You should use pillow on side lying but when  lying with back should not use pillow. Sleeping without pillow is good for natural spinal posture correction.

If you are sleeping g on side ,pl, don't  sleep without pillow,or it will strain your neck Always sleep with pillow of medium thickness n good firmness .it shouldn't  be too hard or too soft.but always use pillow while sleeping in any position. Get physiotherapist consult online on correct ergonomic  n correct posture while sleeping. Sleeping v without pillow is not healthy

Yes, it is definitely good for your spine sleeping without pillow, it will maintain spine anatomical position and keep all vertebrae in normal alignment and curvature.

In my opinion lying on the back you could sleep without a pillow. But on the side, use a pillow.