Clinical Trial Summary
The impression is a necessary step for the orthodontic diagnosis. Digital impression has
recently been introduced by means of intraoral optical scanners. To date, few studies have
compared the conventional alginate impression with the digital impression with intraoral
scanners. These studies have shown that digital impression could have some advantages in
terms of satisfaction and less discomfort for the pediatric patient. Only one study is
randomized and has analyzed patients between 10 and 17 years of age. There are, therefore, no
randomized trials for patients under 10 years of age.
The objective of the study is to compare the conventional alginate impression with the
digital impression of both dental arches in orthodontic patients between 6 and 10 years of
age with a randomized crossover design. In particular, the preference, comfort, impression
taking time and other subjective aspects will be analyzed. This is a monocentric, controlled,
superiority, randomized, crossover, open study.
Inclusion criteria:
- Orthodontic patients between 6 and 10 years of age.
Exclusion criteria:
- Noncompliant patients
- patients with syndromes or systemic diseases
- patients suffering from cleft lip and palate. The patient will be asked which of the 2
dental arch impression procedures they prefer. In addition, patients will be provided
with a questionnaire including VAS (Visual Analogue Scale) for comfort, pain, gag reflex
and breathing difficulty. The VAS will consist of scales from 0 to 10.
As for the calculation of the sample size, this has been done by considering a null
hypothesis for a proportion of 50% in the preference between the two treatments and an
alternative hypothesis of 80%. For alpha set at 0.05, a power of 80% and a dropout rate of
10%, 24 patients are required.
Descriptive statistics will be performed for all variables (frequency and percentage for
qualitative variables and mean and standard deviation for quantitative variables). For the
primary endpoint variable, impression procedure preference, the test will be performed for
one proportion and the 95% confidence interval will be calculated using the Clopper-Pearson
method.
With regard to the secondary endpoint variables, duration of the procedure, comfort, pain,
gag reflex, breathing difficulty, the 2 procedures will be compared with the t-test for
paired data.
An Intention-To-Treat analysis will be performed. In case more than 5 deviations from the
protocol will occur, a sensitivity analysis will also be performed per protocol.
