Electrothermal debracketing: patient acceptance and effects on the dental pulp

Adhesives bond ceramic brackets so effectively that their removal by mechanical forces can fracture the brackets and may damage the tooth surface. Electrothermal debracketers have been developed to facilitate removal; whether the heat generated will damage the underlying pulp is unclear. In our experiment, a prototype device with a high heat tip was used to remove brackets from premolars in patients. The following parameters were evaluated: (1) time required for removal, (2) patient acceptance, and (3) histologic effect on the pulp. Forty-eight experimental teeth planned for orthodontic extraction were bonded by a filled Bis-GMA composite resin and a monocrystalline sapphire bracket. After the chemically cured composite set, debracketing was performed according to the manufacturer's recommendations. Seventeen premolars were not etched or bracketed and served as controls. The interval between heat application and removal of the bracket was timed. Patients were questioned as to sensations during debracketing. Teeth were extracted at 5 to 7 or 28 to 32 days and histologically prepared. Pulps were evaluated for alterations. Brackets were removed in an average of 2.1 seconds, usually at the bracket/composite interface. Patient acceptance was generally positive. Pulpal necrosis was not observed but, in a number of specimens, slight inflammation and odontoblastic disruption occurred at both observation periods.