title: Effect of Green and White Tea Pretreatment on Remineralization of Demineralized Dentin by CPP-ACFP-An Invitro Microhardness Analysis.
abstract: BACKGROUND
  Mechanical performance of dentine is of major significance for the overall function of the teeth. Remineralization of carious dentine is the ultimate goal in re-establishing the functionality of the affected tissue so as to regain and maintain the mechanical properties of dentine. Functional remineralization of the affected dentin involves stabilization of both inorganic and organic component, but Caesin Phosphopeptide Amorphous Calcium Flurophosphate (CPP-ACFP) stabilizes only inorganic content. Hence to stabilize organic content and to bring in functional remineralization the use of anticollagenolytic and antielastastic agent was considered for this study.
  
  
  OBJECTIVE
  To assess and compare the remineralization of artificial carious dentin pre treated with white and green tea, before and after application of CPP-ACFP using microhardness test. Null hypothesis was that both teas did not have any effect on remineralization potential of CPP ACFP.
  
  
  METHODS
  Forty specimens were subjected to artificial caries lesions and were randomly divided into 4 groups based on the application of tea extract followed by CPP-ACFP (groups A & B) and CPP-ACFP followed by tea extracts (groups C & D). All the specimens were subjected to two pH cycling regimen. The specimens were subjected to Vickers microhardness test to obtain the microhardness values. The values were statistically analysed using one-way ANOVA and multiple comparisons with Tukey's HSD procedure.
  
  
  RESULTS
  After the 1(st) and 2(nd) pH cycling in groups A and B, Group B showed significant increase in microhardness values (35.79± 3.12 VHN). But after the pH cycling regimen in groups C and D, microhardness values increased in 1(st) pH cycling (50.03± 3.64 VHN); (50.03±3.64 VHN), respectively but decreased during the 2(nd) pH cycling, (33.94±6.45 VHN); (33.11±6.11 VHN) respectively with the level of significance <0.05.
  
  
  CONCLUSIONS
  The results of this study rejects the hypothesis tested and showed that both the tea extracts increased the microharness values when used prior to the application of remineralizing agent. However, 10% white tea showed better microhardness indicating stabilization of collagen in dentine resulting in functional remineralization.
authors.affiliation: Private Practitioner, Department of Conservative Dentistry and Endodontics, Kerala, India .
authors.forename: Poornima
authors.initials: P
authors.lastname: Jose
authors.affiliation: Professor, Department of Conservative Dentistry and Endodontics, SRM Dental College , Bharathisalai, Ramapuram, Chennai, India .
authors.forename: Kavitha
authors.initials: K
authors.lastname: Sanjeev
authors.affiliation: Head of Department, Department of Conservative and Endodontics, SRM Dental College , Bharathisalai, Ramapuram, Chennai, Tamilnadu, India .
authors.forename: Mahalaxmi
authors.initials: M
authors.lastname: Sekar
keywords: Anticollagenolytic agent; Catechins; Collagen; Extracellular HAp; Intracellular HAp; pH cycling