Hello and welcome to healthcaremagic. Hair oils have no role in arresting hair fall or regrowing new hairs. I would keep a possibility of either Telogen effluvium OR androgenetic alopecia. While I doubt that the accident you had 2 years back has anything to do with your present hair fall. Accident or any major stressor can lead to sudden increase in hair fall(Telogen effluvium) but that usually happens in the first few months after the stress inducing event (3-6 months). I would like to rule out Androgenetic alopecia, which presents as gradual hair thinning and hair fall from the frontal scalp as well as crown and vertex. There might be frontotemporal hair line recession. Minoxidil and finasteride are approved treatments for androgenetic alopecia. I would advice that you see a dermatologist for a confirmatory diagnosis and prescription medications for your hair loss. regards