Effect of Er:YAG laser radiation on pull‑out fracture load of esthetic posts luted to root canal dentin with various resin cements

Abstract

Background: This study investigated the influence of erbium‑doped: yttrium aluminum
garnet (Er:YAG) laser on the pull‑out fracture load of fiber‑reinforced composite (FRC) posts luted
to dentin with different resin cements.
Materials and Methods: In this in vitro experimental study, 90 premolars were endodontically
treated. The post spaces were prepared, and the teeth were divided into three groups dependent
on the cement applied for luting FRC posts: Group 1: An etch‑and‑rinse system, Group 2: A self‑etch
cement, and Group 3: A self‑adhesive cement. After 6 months’ storage and thermocycling, each
group was divided into three subgroups (n = 10) according to the treatment applied for removing
the posts; subgroup 1: Control, subgroup 2: Treatment with Er:YAG laser at 250 mJ, 20 Hz, and
subgroup 3: Treatment by Er:YAG laser at 300 mJ, 10 Hz. The pull‑out load was recorded in Newton.
The data were analyzed by two‑way ANOVA at P < 0.05.
Results: The fracture load was significantly affected by the cementation group (P = 0.005) and
treatment subgroup (P = 0.008). The pull‑out load of self‑etch cement was significantly greater
than that of the self‑adhesive and etch‑and‑rinse systems (P < 0.05). Treatment with Er:YAG laser
caused a significant reduction in pull‑out load of FRC posts (P < 0.05).
Conclusion: The fracture load of fiber posts is influenced by the type of cement and treatment
applied. Post removal would be less challenging when using a self‑adhesive or conventional
etch‑and‑rinse cement or using Er:YAG laser at the FRC‑resin interface.
Key Words: Lasers, post technique, resin cements, erbium