Coronal resistance to fracture of endodontically treated teeth submitted to light-activated bleaching

Pobbe, Priscila de Oliveira da Silva; Viapiana, Raqueli; Souza-Gabriel, Aline Evangelista; Marchesan, Melissa Andréia; Sousa-Neto, Manoel Damião; Silva-Sousa, Yara Teresinha Correa; Silva, Ricardo Gariba

doi:10.1016/j.jdent.2008.07.007

« Previous Next »Journal of Dentistry
Volume 36, Issue 11 , Pages 935-939, November 2008

Coronal resistance to fracture of endodontically treated teeth submitted to light-activated bleaching

Priscila de Oliveira da Silva Pobbe
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil
Raqueli Viapiana
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil
Aline Evangelista Souza-Gabriel
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil
Melissa Andréia Marchesan
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil
Manoel Damião Sousa-Neto
- University of São Paulo, Ribeirão Preto School of Dentistry, Av. Café s/n, Ribeirão Preto 14040-903, SP, Brazil
Yara Teresinha Correa Silva-Sousa
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil
- Corresponding author at: Rua Célia de Oliveira Meireles, 350 Jardim Canadá, 14024-070 Ribeirão Preto, SP, Brazil. Tel.: +55 16 3620 7986; fax: +55 16 3620 7986.
Ricardo Gariba Silva
- University of Ribeirão Preto, School of Dentistry, Av. Costabile Romano 2200, Ribeirão Preto 14096-900, SP, Brazil

Received 7 May 2008; received in revised form 18 July 2008; accepted 21 July 2008.

Abstract

Objectives

The aim of this study was to assess the fracture resistance of endodontically treated teeth submitted to bleaching with 38% hydrogen peroxide activated by light-emitting diode (LED)-laser system.

Methods

Fifty maxillary incisors were endodontically treated, received a zinc phosphate barrier and were embedded in acrylic resin until cemento-enamel junction. The specimens were distributed into five groups (n=10) according to the number of bleaching sessions: GI, no treatment (control); GII, one session; GIII, two sessions; GIV, three sessions and GV, four sessions. The whitening gel was applied to the buccal surface of the tooth and inside the pulp chamber for three times in each session, followed by LED-laser activation. Specimens were submitted to the fracture resistance test (kN) and data were submitted to the Tukey–Kramer multiple comparisons test.

Results

No significant difference (p>0.05) was found between GI (0.71±0.30) and GII (0.65±0.13), which presented the highest strength values to fracture. Groups III (0.35±0.17), IV (0.23±0.13) and V (0.38±0.15) showed lower resistance to fracture (p<0.01) when compared to GI and GII.

Conclusions

The fracture resistance of endodontically treated teeth decreased after two sessions of bleaching with 38% hydrogen peroxide activated by LED-laser system.

Keywords: Fracture resistance, Internal bleaching, Hydrogen peroxide, LED system