Restor Dent Endod.  2014 Aug;39(3):164-171.

How to design in situ studies: an evaluation of experimental protocols

• Sung YH
• Kim HY
• Son HH
• Chang J

Abstract

OBJECTIVES
Designing in situ models for caries research is a demanding procedure, as both clinical and laboratory parameters need to be incorporated in a single study. This study aimed to construct an informative guideline for planning in situ models relevant to preexisting caries studies.
MATERIALS AND METHODS
An electronic literature search of the PubMed database was performed. A total 191 of full articles written in English were included and data were extracted from materials and methods. Multiple variables were analyzed in relation to the publication types, participant characteristics, specimen and appliance factors, and other conditions. Frequencies and percentages were displayed to summarize the data and the Pearson's chi-square test was used to assess a statistical significance (p < 0.05).
RESULTS
There were many parameters commonly included in the majority of in situ models such as inclusion criteria, sample sizes, sample allocation methods, tooth types, intraoral appliance types, sterilization methods, study periods, outcome measures, experimental interventions, etc. Interrelationships existed between the main research topics and some parameters (outcome measures and sample allocation methods) among the evaluated articles.
CONCLUSIONS
It will be possible to establish standardized in situ protocols according to the research topics. Furthermore, data collaboration from comparable studies would be enhanced by homogeneous study designs.

Keyword

In situ; Caries; Demineralization; Remineralization; Erosion; Materials and methods

MeSH Terms

Cooperative Behavior
Outcome Assessment (Health Care)
Publications
Sample Size
Sterilization
Tooth

Figure

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  Figure 1 Flowchart of the data extraction process.

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  Figure 2 Number of in situ caries studies published from 2003 to 2012 according to the main topics. Demineralization, only demineralization of tooth was dealt in the study; Remineralization, remineralization of tooth was included in the study (whether demineralization was included or not), but erosion was not included; Erosion, erosion was included whether other topics were included or not; Others, articles in this category mainly dealt with the abrasive effects of dental products such as toothpastes and tooth whitening agents.

Reference

1. Cochrane NJ, Zero DT, Reynolds EC. Remineralization models. Adv Dent Res. 2012; 24:129–132.

2. Zero DT. In situ caries models. Adv Dent Res. 1995; 9:214–230.

3. Higham SM, Pretty IA, Edgar WM, Smith PW. The use of in situ models and QLF for the study of coronal caries. J Dent. 2005; 33:235–241.

4. Ritter AV, Shugars DA, Bader JD. Root caries risk indicators: a systematic review of risk models. Community Dent Oral Epidemiol. 2010; 38:383–397.

5. Park SE, Yi K, Kim HY, Son HH, Chang J. Elemental analysis of the fluoride varnish effects on root caries initiation. J Korean Acad Conserv Dent. 2011; 36:290–299.

6. Park YS, Cho BH, Lee SP, Shon WJ. Early caries detection using optical coherence tomography: a review of the literature. J Korean Acad Conserv Dent. 2011; 36:367–376.

7. Strech D, Tilburt J. Value judgments in the analysis and synthesis of evidence. J Clin Epidemiol. 2008; 61:521–524.

8. Sakpal TV. Sample size estimation in clinical trial. Perspect Clin Res. 2010; 1:67–69.

9. de Arruda AM, dos Santos PH, Sundfeld RH, Berger SB, Briso AL. Effect of hydrogen peroxide at 35% on the morphology of enamel and interference in the deremineralization process: an in situ study. Oper Dent. 2012; 37:518–525.

10. Sa Y, Sun L, Wang Z, Ma X, Liang S, Xing W, Jiang T, Wang Y. Effects of two in-office bleaching agents with different pH on the structure of human enamel: an in situ and in vitro study. Oper Dent. 2013; 38:100–110.

11. Shellis RP, Ganss C, Ren Y, Zero DT, Lussi A. Methodology and models in erosion research: discussion and conclusions. Caries Res. 2011; 45:Supplement 1. 69–77.

12. Moher D, Liberati A, Tetzlaff J, Altman DG. PRISMA Group. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. J Clin Epidemiol. 2009; 62:1006–1012.