Can open pores be removed permanently?

No, pores can be decreased but true pore sizing can not be permanently removed. I choose a particular laser based upon the size of the pore, skin type of the patient, and expectations. I find that the most reliable method is with INFINI RF, micro needling using energy. This beats all my Fraxel lasers and chemical peel techniques. Very little downtime, and it is ideal for small to medium size pores. Fraxel 1927 comes in a close second in the high density setting. 
Chemical peels such as TCA (70-100%) placed focally in the pores is an excellent treatment for large pores. Fully ablative laser are excellent, but the downtime is long. I use both erbium and CO2. Fractional CO2 medium density can work, but you require 3-6 sessions. More in the pore section in the web reference below. 

Pore size reduction treatments should be tailored according to the patient.
Regards

Dr Davin Lim

Laser and aesthetic dermatologist

Brisbane, Australia.