Having had the same problem, I can wholeheartedly recommend Bioplast jewellery.
Even a year after I had my cartilage pierced, it would go through phases of getting inflamed and infected. I read so many guides on the internet about how to heal cartilage piercings, and none of them helped me. I was getting close to just taking it out.
I'd tried different materials (surgical steel and titanium), different types of jewellery (rings, barbells, labret studs) and even tried different sizes to see if that was the problem. As it turned out, I was just really sensitive to piercings. The last thing I tried was Bioplast jewellery from Body Jewellery Shop. The labret studs and piercing retainers have the added bonus of being really easy to put in place - as opposed to trying to fit the ball onto a ball-closure ring when you can't see what you're doing, your hand is in the way, and your ear already hurts!
From what I remember, the piercing felt less inflamed by that evening, and within a couple of weeks it had stopped hurting altogether. I left the same jewellery in for the year that followed, because I thought it would just get infected again if I put a titanium ring through it. I eventually lost the end part of the jewellery, though, and put a ring through anyway, and it's been fine like this for the past six months.
There are a few other things I'd recommend while healing:
- Wash with warm salt water at least twice a day. I know everybody says this, but that's because it works.
- If the piercing in question is on your ear, sleep with that side of your face away from the pillow.
- Be really careful brushing/washing your hair, because it can really hurt if you catch it.
- I carried an alcohol-free antibacterial hand sanitiser spray around with me (diluted with a little water) and sprayed it on my ear if it was hurting when I was out. I'm not sure if this did any good, but it did soothe it a lot.