NaOCl effects on primary and permanent pulp chamber dentin.
OBJECTIVE
The dentin quality of primary and permanent pulp chamber was inspected by Fourier-transformed Raman spectroscopy (FT-Raman) and scanning electron microscopy (SEM). Fragments of pulp chamber dentin were obtained from 20 human molar crowns (primary and permanent).


METHODS
The fragments were assigned to 8 groups (n=5)-Primary teeth: G1, pulp chamber dentin; G2, pulp chamber dentin irrigated with NaOCl 1% (30 min); G3, pulp chamber dentin irrigated with NaOCl 1% (30 min) and etched by 35% phosphoric acid; G4, pulp chamber dentin etched by 35% phosphoric acid. Permanent teeth: G5, pulp chamber dentin; G6, pulp chamber dentin irrigated with NaOCl 1% (30 min); G7, pulp chamber dentin irrigated with NaOCl 1% (30 min) and etched by 35% phosphoric acid; G8, pulp chamber dentin etched by 35% phosphoric acid. The spectra were subjected to the Cluster analysis. The SEM images were scored.


RESULTS
Inorganic content: There was a difference between primary and permanent dentin. The groups treated with NaOCl were statistically similar between them, but differed from the groups not treated. Organic content: There was no difference between primary and permanent dentin. The groups became similar after NaOCl and phosphoric acid treatments. The microscopic images showed the presence of calcospherites on permanent dentin and their absence on primary dentin.


CONCLUSIONS
The NaOCl changed the inorganic content in both dentitions; regardless of the following phosphoric acid etching. However, the chemical changes caused by NaOCl were not detected by SEM when it was followed by etching.
Borges
Ana Flávia Sanches
AF
Latin American Institute of Research and Teaching in Dentistry (ILAPEO), Brazil.
Bittar
Renata Andrade
RA
Pascon
Fernanda Miori
FM
Sobrinho
Lourenço Correr
LC
Martin
Airton Abrahão
AA
Puppin Rontani
Regina Maria
RM
D000134:Acid Etching, Dental; D003786:Dental Pulp Cavity; D003804:Dentin / Q000187:drug effects*; D019229:Dentition, Permanent; D005583:Fourier Analysis; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008963:Molar; D010756:Phosphoric Acids / Q000494:pharmacology; D012388:Root Canal Irrigants / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000494:pharmacology*; D013059:Spectrum Analysis, Raman / Q000379:methods; D019228:Tooth Crown; D014094:Tooth, Deciduous
D010756:Phosphoric Acids; D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite; C030242:phosphoric acid