Letters From Our Readers

To: Editor, The Angle Orthodontist

Re: Retention of sealants during orthodontic treatment: An in vitro comparison of two etching protocols. Chau C, Campbell PM, Deljavan N, Taylor RW, Buschang PH. Angle Orthod. 2015; 85:750-756.

I would like to congratulate the authors on this interesting study. When I was reading it, I had a few questions about the methods used and how some variables may have been controlled. Can you please comment on how the following factors may have affected the outcome observed?

• 1.

  Temperature is known to have a plasticizing effect, and therefore, in in vitro studies, a constant temperature (37C) or thermal cycling (5-55C) temperature should be considered. Therefore, would it not be interesting if the study were to take into account the variations in temperature that may occur intraorally?

• 2.

  A basic requisite of an artificial environment consists of the use of artificial saliva that would react with the test material in a manner similar to that of natural saliva. If artificial saliva had been used to simulate an environment with chemical properties similar to those of the oral cavity, do you think that may have affected the results?

• 3.

  One of the aims of the study was to characterize the type and location of sealant loss and, to do this, initial photographs of each sample were used for later comparison. However, there are other methods of evaluating the tooth surface that are capable of measuring the surface analyzed quantitatively in order to reveal more precise results. What were the advantages of the method chosen over other, more quantitative methods described in the literature, such as optical profilometry, for example?

Thank you once again for taking the time to answer my questions.