IADR Abstract Archives
Warm Gutta-percha Techniques Regulate Heat-shock-proteins of Cementoblasts
Objectives: We previously confirmed that heat increase during the application of warm-gutta-percha techniques reduced the viability of cementoblasts in an in vitro cell-culture study. The aim of the present study is to determine the effect of continuous wave of condensation technique (CWCT) and thermoplastic gutta-percha injection (TGI) technique on the mRNA expressions of heat-shock proteins (HSP) of the immortalized mouse cementoblasts (OCCM.30).
Methods: Crowns of twenty human premolar-teeth with single and straight canals were removed. The root-canals were prepared up to the ProTaper Next X5 file in combination with two ml 2,5%NaOCl solution. Roots (10-mm height) were sterilized (121°C for 20min) first for the cell-culture medium and placed vertically to the cell-culture dishes using tissue-culture insert by opening holes according to the root-diameter after removal of 1mm from the apex for appropriate adaptation to the petri-dishes surfaces. Six groups were created: C1: Control 1 without roots; C2: Control 2, roots without canal filling; AH: Roots filled with AH Plus; SC: Roots filled with single-cone technique; CWCT and TGI: Roots filled with CWCT and TGI. Total RNA was isolated at 24hrs and cDNA synthesis was performed. mRNA expressions of HSP-27, HSP-70, HSP-90 were examined by quantitative Real-time polymerase chain reaction (RT-PCR) analysis.
Results: Reduction in the mRNA expressions of HSP27, HSP70, HSP90 was recognized in all test groups when compared to C1 group in the cementoblasts (p<0.01). When the both warm gutt-percha techniques were compared with SC technique (an appropriate control), decrease in mRNA expression of HSP27 and HSP90 was noted (p<0.01). HSP70 tanscript was similar in CWCT with SC. Higher HSP70 mRNA expression was observed in TGI when compared to SC group.
Conclusions: Within the limitations of this study, it was concluded that warm gutta-percha techniques reduced heat-shock proteins which have been associated with the cell survival and repair process.
Methods: Crowns of twenty human premolar-teeth with single and straight canals were removed. The root-canals were prepared up to the ProTaper Next X5 file in combination with two ml 2,5%NaOCl solution. Roots (10-mm height) were sterilized (121°C for 20min) first for the cell-culture medium and placed vertically to the cell-culture dishes using tissue-culture insert by opening holes according to the root-diameter after removal of 1mm from the apex for appropriate adaptation to the petri-dishes surfaces. Six groups were created: C1: Control 1 without roots; C2: Control 2, roots without canal filling; AH: Roots filled with AH Plus; SC: Roots filled with single-cone technique; CWCT and TGI: Roots filled with CWCT and TGI. Total RNA was isolated at 24hrs and cDNA synthesis was performed. mRNA expressions of HSP-27, HSP-70, HSP-90 were examined by quantitative Real-time polymerase chain reaction (RT-PCR) analysis.
Results: Reduction in the mRNA expressions of HSP27, HSP70, HSP90 was recognized in all test groups when compared to C1 group in the cementoblasts (p<0.01). When the both warm gutt-percha techniques were compared with SC technique (an appropriate control), decrease in mRNA expression of HSP27 and HSP90 was noted (p<0.01). HSP70 tanscript was similar in CWCT with SC. Higher HSP70 mRNA expression was observed in TGI when compared to SC group.
Conclusions: Within the limitations of this study, it was concluded that warm gutta-percha techniques reduced heat-shock proteins which have been associated with the cell survival and repair process.