Effect of topical fluoride on retention of pit and fissure sealants.

PURPOSE: The purpose of this study was to evaluate the clinical effect of topical fluoride on retention of light-cured (CLC) and self-cured (CSC) pit and fissure sealants. METHODS: CLC and CSC sealants were placed in vivo on opposite sides of the arch before and after fluoride treatment. A total of 122 sealants were placed on virgin permanent molars and premolars of 16 dental hygiene students enrolled in a two-year program. Sealant retention in both fluoridated and non-fluoridated teeth was evaluated at 6, 12, and 18 month intervals. RESULTS: Overall sealant retention for both fluoridated and non-fluoridated teeth at 6, 12 and 18 months was 68%, 48%, and 49%, respectively. There was a significant difference (p < 0.001) when fluoridated vs. non-fluoridated teeth were compared. Retention was greater on the fluoridated teeth, with respect to the sealant material (CLC-fluoride). Significant differences (p < 0.001) were found when CLC-fluoride and CLC-no fluoride treatment groups were compared. However, no significant differences were found in retention when CSC-fluoride and CSC-no fluoride groups were compared, or when CLC was compared to CSC irrespective of fluoridation. Significant differences (p < 0.0001) were found when sealant retention on molars was compared to premolars--retention of sealants was greater on premolars. CONCLUSION: This study suggests that sealant retention may not be adversely affected by a topical fluoride treatment applied immediately prior to placement.

Intensity of curing lights affected by barriers.

PURPOSE: Infection control with the use of curing lights is a problem for many oral health care offices. The purpose of this study was to determine if the use of protective barriers with curing light tips would affect the intensity of the light output of commercial light curing units as measured by a commercial radiometer. METHODS: Four different disposable barriers were tested on four light curing units to determine light intensity output (mW/cm2). Three readings of light output for each light source were obtained in each case and means and standard deviations were calculated. Means comparison was performed using analysis of variance and Tukey-Kramer intervals at the .05 significance level. RESULTS: The factors of barrier (p = .001) and light curing unit (p = .0001) were significant. The interaction (p = .54) was not significant. Light intensity output decreased significantly with addition of every barrier, except for the Sani-Shield barrier with all the light units tested, and Protectop barrier with the Coltolux 4 unit. The greatest reductions occurred with the addition of the All Purpose Adhesive Covering barrier to all light units except the Dentsply (glass tip), and with the Protectop barrier to the Dentsply light unit (glass tip). CONCLUSIONS: Barrier protection can be used with curing light tips only after determination that the emitted light intensity output is adequate.

Operating air pressure of disposable angles.

PURPOSE: This study was conducted to determine if air pressure of 20 pounds per square inch (psi) was sufficient to operate disposable prophylaxis angles smoothly and efficiently without stalling. METHOD: Five specimens of 15 types of disposable angles were evaluated by four dental hygienists to determine the minimum speed required for smooth operation. A fifth person operated the rheostat and increased the air pressure psi until signaled by the operators to stop once reaching a sufficient air pressure for operating the angle without stalling. Air pressure values were recorded for each test. Means and standard deviations were calculated for all raters for each angle. Data were analyzed using a two-way analysis of variance. Since there were no significant trends among raters, data for raters were combined for each angle and analyzed by a one-way analysis of variance. The Tukey-Kramer interval at a 0.05 significance level for comparisons among angles was determined. RESULTS: Study results showed that air pressure to achieve minimum speed required for smooth operation varied among the angles from 16.8 psi to 28.8 psi. The mean air pressure was 23.0 psi for angles with firm cups, 20.3 psi with soft cups, and 18.0 psi with regular cups. Some soft cup angles required air pressure greater than 20 psi while some firm cup angles required less than 20 psi. The regular flexibility of cup angles tested required less air pressure than 20 psi. CONCLUSION: The minimum air pressure psi required for smooth operation of disposable angles varied. Generally, air pressure greater than 20 psi was required to operate angles with firm cups, while less than 20 psi was required to operate angles with soft or regular cups.