The value of repetition and reinforcement in improving oral hygiene performance.

The purpose of this study was to assess the value of including repetition and reinforcement in a dental health education program for school children. Sixty-one pupils, 11 to 13 years of age, were divided into three groups according to room assignments. Group I (control) received no oral hygiene lectures or instructions until the conclusion of the experiment. Group 2 (nonreinforced) received one lecture and a toothbrushing lesson, but no repetition or reinforcement. Group 3 (reinforced) received the same program as Group 2 on the initial visit and also received two additional visits for repetition and reinforcement of the lectures and instructions, plus a final summary lecture. Six visits were conducted at intervals of 0, 1, 5, 3, 8, 20 and 52 weeks, following a double-blind experimental format. PHP scores were obtained on all subjects on each of the six visits. It was concluded that the repetition and reinforcement components of this dental health education program were of significant value in improving the oral hygiene performance of the school children over a period of 1 year. The findings provide evidence of the desirability of incorporating these concepts in plaque-control program.

Effect of root canal sealers and irrigation agents on retention of preformed posts luted with a resin cement.

This study examined the effect of three sealers and four irrigants on retention of Dentatus preformed posts luted with Panavia 21 resin cement. Gutta-percha with one of the following sealers--EWT, AH26, Nogenol, or no sealer (control)--was used to fill the root canals of 160 autoclaved incisor and premolar tooth roots. After 72 hr 8 mm post spaces were created with Dentatus Probos Pathfinders and Dentatus reamers. After irrigating the post spaces with saline, 5.25% NaOCl, 50% citric acid followed by NaOCl, or 40% H3PO4, followed by NaOCl, Panavia 21 TC cement was introduced into the canal on the Dentatus #4 stainless steel post's threads. An up-and-down and counterclockwise motion and then a forward twist seated the posts without engaging dentin. Mesiodistal and faciolingual radiographs visualized the chambers. After 72 hr posts were removed axially with an Instron at 5 mm/min. Surprisingly, using Nogenol sealer reduced post retention whereas EWT and AH26 increased retention compared with no sealer. Post retention improved after acid etchants, especially for AH26.