Is failure of two implants related to the CPAP use?

Yes it is a factor.

CRS, Please explain your answer. I am curious.

These units cause pressure on a new surgical flap and the air also dries out the tissues. They are very hard on the periodontium. Blowing air on a surgical site all night is not a good thing. Surgical flaps need to be allowed to heal undisturbed for optimal results.

I believe the drying of the mouth is a major factor.Weather the actual cpap machine places enough pressure to disturb the flap, i'm not really sure.

Nasal CPAP keeps a continuous pressure in the nasal airways at whatever setting is prescribed. As long as the sinus Ostia are patent, the sinus is exposed to that pressure all night. It can disrupt the graft. Think about it, we put our patients on sinus precautions after sinus lifts and closure of oro-antral fistulae. CPAP is the exact opposite of sinus precautions.

What about LDL and Vitamin D levels? Overweight, poor diet,no sleep or sunshine?

If you want absolutes there really aren't any in medicine, and no one knows really why implants fail. There are many reasons but in this case the CPAP appears to be a significant factor. The factors you mention are factors but were not stated in the case. It is really sad that there are so many obese people who can't breathe when they sleep but CPAP and sleep apnea are multifactoral and I just made a judgement on whether this patient is obese! So I go to the common sense answer and try to eliminate the most likely factor the CPAP which I have seen the damage it can cause, pressure, drying out and flap trauma just like when a flipper is worn over a grafted site. Many things can affect healing, my experience just comes with time and observation. In residency we had a term for this " piss poor protoplasm" but some patients, God bless 'em truly amaze me how well they heal. I guess it keeps our jobs interesting and humbling!

How many times can I say factor in a post?

Spin off question: I am looking at getting 4 implants placed at the same time with 2-3 bone grafts and I am on a higher bipap level pressures for severe sleep apnea We are hoping to use my current invisalign aligner trays to protect the surgical site to hopefully allow me to use my bipap therapy sooner. The last procedure I had showed an increase in my already delayed healing when I was without my apnea therapy. Any thoughts or suggestions?