title: Light-cured glass ionomer cement as a retrograde root seal.
abstract: A light-cured ionomer cement was investigated as a retrograde root seal, without a retrograde cavity. This was compared with the material used in a retrograde cavity, and with a conventional glass ionomer cement, as a seal. The adaptation and sealing ability of the test materials were assessed using a confocal optical microscope with a fluorescent dye. The root canals of 40 extracted human single-rooted teeth were prepared and filled with gutta-percha and sealer. All the teeth were subsequently apicected, then divided into four equal groups. In one group, a retrograde cavity was prepared, and the light-cured glass ionomer cement was placed as a retrograde root filling. No retrograde cavities were prepared in the three remaining groups. The light-cured glass ionomer cement was applied directly onto the apicected root face. Two different thicknesses of light-cured glass ionomer cement were tested, a thin layer (approximately 1 mm) in one group, and a thicker layer (> 1 mm) in another group. A conventional glass ionomer cement was used in the last group, and applied directly onto the root face in a single thickness (approximately 1 mm). In the group where the light-cured glass ionomer cement was used in a retrograde cavity, the material was often well adapted to one cavity wall, but gaps were found on the opposite wall. The light-cured and conventional glass ionomer cement retrograde root seals were well adapted to the root face, regardless of the thickness of material used. The thinly applied (approximately 1 mm) light-cured glass ionomer cement retrograde root seals permitted the least leakage.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Conservative Dental Surgery, United Medical and Dental Schools, Guy's Hospital, London.
authors.forename: B S
authors.initials: BS
authors.lastname: Chong
authors.forename: T R
authors.initials: TR
authors.lastname: Pitt Ford
authors.forename: T F
authors.initials: TF
authors.lastname: Watson
mesh_terms: D000704:Analysis of Variance; D001047:Apicoectomy; D003763:Dental Leakage; D005899:Glass Ionomer Cements; D006801:Humans; D012184:Retrograde Obturation / Q000379:methods*; D012387:Root Canal Filling Materials; D013499:Surface Properties
chemical_list: D005899:Glass Ionomer Cements; D012387:Root Canal Filling Materials; C074807:BaseLine dental cement; C067790:Vitrabond