Radiographic – of or referring to dental x-rays.

Raphe – a union of soft tissue found on the upper palate.


Rebase – the process in which only the inner surface of a denture is replaced by new material.  Also known as relining.

Remineralization – a process enhanced by the presence of fluoride where partially decalcified enamel, dentin, and cementum become recalcified by mineral replacement.

Resin Filling – a tooth-colored restorative material.  The work “composite” refers to the mixture of filler particles in a liquid resin.  The resin most commonly used is BIS-GMA (bis-gammamethylmetacrylate).  Filler particles are added to alter the color and wear characteristics of the resin.  Common filler particles are silica, aluminum, zinc, tin, copper, and iron.

Resorb – to dissolve into the tissue.

Restorations – any replacement for lost tooth structure or teeth.  Common restorations include dental bridges, dental crowns, dental fillings, and dental implants.

Restorative Dentistry – is the practice or process of reconstructing a person’s teeth, gums, jaw, or any combination of these in an otherwise normal mouth. Reconstructive dentistry is more extensive than cosmetic dentistry and is usually performed under conscious sedation. The difference between cosmetic and reconstructive dentistry is often defined loosely by insurance companies, as many will pay for reconstructive dentistry such as repairing or rebuilding broken or chipped teeth, but will not pay for cosmetic dentistry.

Retainer – a removable appliance used following orthodontic treatment to maintain the teeth in their proper positions.  Retainers should be worn as directed by an orthodontist.

Ridge – a linear elevation.

Root Canal Therapy (RCT) – an endodontic procedure used to save an abscessed tooth.  During this procedure the pulp chamber is cleaned out, disinfected, and filled with a permanent filling to prevent damage and decay in the future.

Root Chamber – the portion of the root that is not bifurcated or trifurcated.

Root Planing – the removal of hard deposits from the root surface below the gum line.  Often performed alongside a scaling treatment for periodontal disease.

Rugae – elevated folds or wrinkles of soft tissue in the front part of the palate.