I am 75, i have a tmj problem, where my jaw joint is. is twin block or bionator better for tmj conditions?

Second opinion: Tmj-related treatment varies greatly depending on the reason what problems you are experiencing and why. This is called diagnosis and can vary from doctor to doctor especially if your TMJ dysfunction is atypical. First, ask your doctor to understand his/her diagnosis ; treatment. If you are still unsure about the treatment plan ask for a referral (or find by yourself) to get a second opinion.

Twin blocks bionator: are not used and ineffective for TMJ. They are used for a rapid functional correction of malocclusion by the transmission of favorable occlusal forces to occlusal inclined planes that cover the posterior teeth. See Orofacial Pain practitioner for diagnosis and treatment.

Tangentially: Both Twin Block and Bionator are modestly successful in altering jaw growth in tweens, totally ineffectual in adults. Both appliances hold teeth apart, which may relieve stress on jaw joints, but there are better alternatives. For symptomatic relief you would be best served with an occlusal orthotic.

Depends: Neither should be first line treatment. You should start with simpler, less expensive treatment like meds, self are program, soft diet, heat or cold. Which device is better if you need a device depends on factors beyond the information given here.