Restor Dent Endod.  2014 Nov;39(4):265-269. 10.5395/rde.2014.39.4.265.

Effect of ultrasonic tip designs on intraradicular post removal

• Aguiar AC
• de Meireles DA
• Marques AA
• Sponchiado Junior EC
• Garrido AD
• Garcia LD

• KMID: 2316906
• DOI: http://doi.org/10.5395/rde.2014.39.4.265

Abstract

OBJECTIVES
To evaluate the effect of different ultrasonic tip designs on intraradicular post removal.
MATERIALS AND METHODS
The crowns of forty human canine teeth were removed, and after biomechanical preparation and filling, the roots were embedded in acrylic resin blocks. The post spaces were made, and root canal molding was performed with self-cured acrylic resin. After casting (Cu-Al), the posts were cemented with zinc phosphate cement. The specimens were randomly separated into 4 groups (n = 10), as follows: G1 - no ultrasonic vibration (control); G2 - ultrasonic vibration using an elongated cylindrical-shaped and active rounded tip; G3 - ultrasonic vibration with a flattened convex and linear active tip; G4 - ultrasonic vibration with active semicircular tapered tip. Ultrasonic vibration was applied for 15 seconds on each post surface and tensile test was performed in a Universal Testing Machine (Instron 4444 - 1 mm/min).
RESULTS
G4 presented the highest mean values, however, with no statistically significant difference in comparison to G3 (P > 0.05). G2 presented the lowest mean values with statistically significant difference to G3 and G4 (P < 0.05).
CONCLUSIONS
Ultrasonic vibration with elongated cylindrical-shaped and active rounded tip was most effective in reducing force required for intraradicular post removal.

Keyword

Post removal; Tip design; Ultrasonic device

MeSH Terms

Crowns
Cuspid
Dental Pulp Cavity
Fungi
Humans
Ultrasonics*
Vibration
Zinc Phosphate Cement
Zinc Phosphate Cement

Figure

• 

  Figure 1 Ultrasonic tips used in the study. (a) Elongated cylindrical-shaped and active rounded tip (G2); (b) Flattened convex and linear active tip (G3); (c) Active semi-circular tapered tip (G4).

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