title: Effect of bromelain enzyme for dentin deproteinization on bond strength of adhesive system.
abstract: OBJECTIVE
  To assess the deproteinizing effect of bromelain enzyme and compare it with 5% sodium hypochlorite (NaOCl) on shear bond strength before application of the adhesive system.
  
  
  METHODS
  A total of 30 extracted human premolars were divided into three groups, each one consisted of 10 teeth. The occlusal surface was wet ground to expose superficial dentin. In Group 1, teeth were etched; in Group 2, teeth were etched and deproteinized with bromelain enzyme; in Group 3, teeth were etched and deproteinized with 5% NaOCl. Upon completion of the adhesive procedures, resin composite was inserted into the plastic tube and light-polymerized. All specimens were stored at 37°C in water for 24 h, and the specimens were transferred to the universal testing machine, and then subjected to shear bond strength analysis at a crosshead speed of 1.0 mm/min.
  
  
  METHODS
  Data were statistically analyzed using one-way analysis of variance and unpaired t-test at a significance level of 0.05. The statistical analysis was performed using SPSS version 12.0.1 for Windows (SPSS Inc., Chicago, IL, USA).
  
  
  RESULTS
  The bond strength results were significantly influenced by the application of bromelain enzyme. Statistically significant differences were not demonstrated in control group and NaOCl-treated group. The highest bond strength was seen in bromelain enzyme-treated group.
  
  
  CONCLUSIONS
  Within the limitations of the present study, it was concluded that removal of unsupported collagen fiber with bromelain enzyme after acid etching results in improved bond strength.
authors.affiliation: Department of Conservative Dentistry and Endodontics, College of Dental Sciences, Davangere, Karnataka, India.
authors.forename: Kirti
authors.initials: K
authors.lastname: Chauhan
authors.affiliation: Department of Conservative Dentistry and Endodontics, College of Dental Sciences, Davangere, Karnataka, India.
authors.forename: Revaplar Siddaveerappa
authors.initials: RS
authors.lastname: Basavanna
authors.affiliation: Department of Conservative Dentistry and Endodontics, College of Dental Sciences, Davangere, Karnataka, India.
authors.forename: Vasundhara
authors.initials: V
authors.lastname: Shivanna
keywords: Bromelain enzyme; shear bond strength; sodium hypochlorite