Table 2. Application of CAT in pediatric patients.

CAT, clear aligner therapy

Authors and year	Study	Conclusion
Abraham et al., 2016 [12]	"Modified clear tray aligners" were utilized to rectify the anterior crossbite in an 8-year-old child.	The acceptance of treatment has increasingly emphasized aesthetics and convenience, as children have become highly conscious of their appearance when wearing orthodontic appliances.
Staderini et al., 2020 [13]	Two 8-year-old children with an anterior crossbite had successful treatment with CAT, with no major discomfort or consequences, after the problem was fully resolved in five months.	Given this result, CAT may be especially useful for correcting teeth that are still growing and flexible enough to realign.
Levrini et al., 2021 [14]	A total of 20 patients with a mean age of 8.9 years were treated with Invisalign® First for maxillary expansion and showed significant increases in arch width and perimeter, while arch depth and molar inclination decreased. The alveolar expansion was observed at all reference points.	The study suggests Invisalign® First clear aligners as a reasonable alternative for mild crowding or limited transverse maxillary deficiency compared to traditional expanders.
Zou et al., 2022 [15]	A 4-year-old child with an anterior crossbite and facial asymmetry was treated with CAT for about 18 weeks.	It showed great potential in early intervention for malocclusion in deciduous teeth.
Lombardo et al., 2023 [16]	A total of 32 children were given two different orthodontic expansion treatments (17 children: rapid maxillary expansion; 15 children: clear aligners) for the correction of malocclusions.	A clear aligner system was found to be more efficient than rapid maxillary expansion with better control of upper first molar crown angulation and increased palatal area; the anterior segment of the arch could achieve greater expansion.
Lione et al., 2023 [17]	A total of 23 subjects with a mean age of 9 years underwent non-extraction treatment with Invisalign First System® clear aligners to assess the transverse development of the maxillary arch.	For individuals who needed to develop their maxillary arches, the Invisalign First System® worked well. The largest net increase was seen in the upper first deciduous molars, and rotational movement around the palatal root resulted in an increased mesial breadth in the upper first molars.
da Silva et al., 2023 [18]	A total of 32 patients with a mean age of 9.3 years were treated with a 2x4 fixed appliance and clear aligners for about 8 months for the correction of maxillary incisor position irregularities in mixed dentition.	Clear aligners and 2×4 mechanics showed comparable efficacy and efficiency in correcting maxillary incisor positions during the mixed dentition phase.