What is ortho removable appliance?

Retainer: Usually this means a retainer. But it just means that the device is not locked into place, it can be removed when desired by dentist and /or patient.

Used in ortho: During orthodontic treatment, removable appliances may be used to influence jaw growth or to stabilize new bite positions. Often, they are utilized in conjunction with orthodontic treatment.

Just what is sounds: An appliance used to adjust your teeth/bite that can be removed.

Can be removed: Orthodontist may prescribe some types of appliances (devices) that are removable by the patient when eating or cleaning their teeth. The risk is that the patient will not comply with regular wear of such devices. Even some orthodontic retainers (used to hold teeth after treatment) are also considered removable appliances.

Retainer: This can be active or passive.

Ortho appliances: Fixed, attached to the teeth, or removable, literally can be taken out. Fixed appliances work 24/7. Removable appliances work only when worn. Fixed appliances more than 90% effective. Removable appliances may be less than 50% effective.