Can hot oil treatment cure dry hair?

It will certainly help your hair feel better, but if your hair is dry because it is damaged or over processed it won't "repair" your hair. The only thing that will fix that is lots of love, regular trims, and time. But give it a whirl, maybe try a deep conditioning treatment too. I wish you luck. 

BTW...you mentioned you had fine and silky hair, and not it is dry and frizzy, have you been doing anything different to make it change so much?

Condition condition condition.  Put leave-in conditioner on before you use that straightener.  Neutrogena Triple Therapy brand is great.  You could also use a leave-in detangler/conditioner with silicones which will give the illusion of smoother hair.  Look for products with ingredients that have "cones" at the end of their name.  That's a silicone.  Glob more leave-in conditioner on your hair at overnight.  Don't wash your hair everyday.  Condition your hair everyday!

A great product is "Loreal Professional Intense Repair Hair Masque."  After you shampoo, towel dry your hair to get the excess water out of your hair and then apply about a pinky's length of the product in your hair ... let it sit for about 3-5 minutes, then rinse.  I guarantee within two weeks your hair will be dramatically improved.

I had very damaged hair from over processing and dying and heat appliances and all that other "good" stuff--I've stopped dying my hair and minimized the amount of heating tools I use and my hair is coming back to life.  It's been about 3 months since I last dyed my hair and about 2 since I started using the Loreal Professional Intense Repair Hair Masque.  Since damage cannot be really be "repaired" your best bet is to use products like these that will prevent and strenghten your hair.  I've been getting regular trims and the "dead" stuff is pretty much almost all gone--I'd say another two trims and I'll be set.

Oh, I believe the product is only available at salons--it's about 20 dollars--but it will last you a long time.  I've had mine for 2 months already and I still have more than half of the container left--I use it at least 4 times per week, sometimes 6.  All you need is a very small amount--any more than what i suggested above and you'd just be wasting it.

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