Determination of plasma catecholamines in dogs after experimental gingival retraction with epinephrine-impregnated cord.

Blood catecholamine levels were determined by high-performance liquid chromatography after placement of the cord around two teeth in a random sequence of the following treatments: (1) untreated cord to intact gingival crevice (C), (2) epinephrine cord to intact crevice (E1), and (3) epinephrine cord to a crevice disrupted with a tapered diamond bur to simulate a subgingival procedure such as in crown preparation (E2). Each cord was left in place for 30 min while blood was drawn from the external jugular vein at 0, 5, 10, 20 and 30 min, and at 10 and 30 min after removal of the cord. Catecholamine values were compared to baseline (time 0) measurements. Treatment C resulted in no significant change in blood catecholamines. Treatment E1 caused a significant increase (p less than 0.01) in blood epinephrine levels, reaching a 641 per cent increase at 30 min. Treatment E2 produced a highly significant increase (p less than 0.001) in blood epinephrine with a greater than 5000 per cent increase 10 min after cord removal. Norepinephrine and dopamine levels were not significantly altered by any of the treatments.

Management of the dental patient receiving corticosteroid medications.

Patients who have undergone therapy with glucocorticoids present unique problems for the dentist. Persons currently receiving steroid therapy have altered responses to infection and wound healing. More important, many patients who are taking or have taken glucocorticoids have a high risk of developing acute adrenal insufficiency when placed in a stressful situation. When treating patients with a history of glucocorticoid therapy, one must obtain precise information from the medical history to determine the relative risk of pituitary-adrenal suppression. If the patient is at risk, the dentist must determine the need for the following prophylactic measures: (1) systemic antibiotic therapy, (2) anxiety control, and (3) increased administration of glucocorticoids (steroid prep). If a patient experiences adrenal crisis, the dentist must be capable of interpreting the signs and administering appropriate therapy.

Self-sterilization of the electrosurgery electrode.

Sterilization of the electrode used in electrosurgery has been assumed to occur at the instant of contact of the energized electrode tip to a grounded source. This study evaluated whether the time of electrode activation or the amount of energy delivered is important in the self-sterilization process. Standard bacteriologic culturing techniques were employed to assess sterility of the electrode tip following activation. Total time of application of the current and the energy used were recorded on audiotape and later tabulated. The data indicate that the time of energizing and the energy units used are critical in the sterilization of the electrode tip. These results confirm that self-sterilization of the electrosurgery electrode tip occurs, but full confidence is not realized with the time intervals commonly employed in clinical practice. The electrode tip must be considered a potential source of bacterial contamination of electrosurgically managed dental procedures.

Histologic evaluation of gingival response to an electrosurgical blade.

Lateral heat production during the use of electrosurgical procedures in the oral cavity causes denaturation of the connective tissue adjacent to the incision line. This study evaluated the denatured zone following electrosurgery incision in dog gingiva with a traditional tungston wire electrode and a no. 15 surgical blade adapted for electrosurgery use. The effects of using a passive electrode during surgical procedures and using an "autosensor" circuit to control power adjustment were also evaluated. It was found that a surgical blade adapted for electrosurgery produces a zone of denatured tissue that is not statistically different from that produced with a wire electrode. Moreover, no differences were noted between incisions produced with manual power adjustment and those with power controlled by the "autosensor" circuit. A significantly wider zone of denatured tissue was produced when incisions were made without a passive electrode in place.

Effects of electrosurgery on dog pulps under cervical metallic restorations.

Fifty-four Class V amalgam restorations were placed in nine beagle dogs to determine whether electrosurgical effects on pulp tissue could be altered by the presence of metallic restorations. An electrosurgical technique was performed, simulating clinical procedures for tissue removal while traversing the restorations. Time and power-use measurements were recorded for each operation. All operations that were performed within a time range imitating clinical procedures failed to produce changes in pulpal histology. When electrosurgical exposures were extended beyond 0.4 second contact with restorations, pulpal alterations occurred in the majority of specimens.