Advancing the assessment of pacifier effects with a novel computational method

Abstract

Background: Numerous studies have demonstrated a high likelihood of malocclusions resulting from non-nutritive sucking. Consequently, quantifying the impact of pacifiers can potentially aid in preventing the development or exacerbation of malocclusions and guide the design of improved performance pacifiers.

Methods: This work proposes and assesses a computational methodology that can effectively gather crucial information and provide more precise data regarding the consequences of non-nutritive pacifier sucking. The computational framework utilized is based on solids4Foam [1, 2], a collection of numerical solvers developed within the OpenFOAM® computational library [3]. The computational model focuses on the palate of a six-month-old baby and incorporates various components such as palate tissues, pacifier and tongue, and considers the negative intraoral pressure generated and the tongue displacement. Different models were tested, each offering varying levels of detail in representing the palate structure. These models range from a simplified approach, with one tissue, to a more intricate representation, involving up to five different tissues, offering a more comprehensive palate model compared to existing literature.

Results: The analysis of results involved examining the distribution of stress on the palate surface, as well as the displacement and forces exerted on the dental crowns. By comparing the obtained results, it was possible to evaluate the precision of the approaches previously described in the literature. The findings revealed that the predictions were less accurate when using the simplified model with a single tissue for the palate, which is the most common approach proposed in the literature. In contrast, the results demonstrated that the palate model with the most intricate structure, incorporating five different tissues, yielded distinct outcomes compared to all other combinations.

Conclusions: The computational methodology proposed, employing the most detailed palate model, has demonstrated its effectiveness and necessity in obtaining accurate data on the impact of non-nutritive sucking habits, which are recognized as a primary contributor to the development of dental malocclusions. In the future, this approach could be extended to conduct similar studies encompassing diverse pacifier designs, sizes, and age groups. This would foster the design of innovative pacifiers that mitigate the adverse effects of non-nutritive sucking on orofacial structures.

Keywords: Computer simulation; Computer-aided engineering; Deciduous tooth; Malocclusion; Mouth; Sucking behavior.

Fig. 1

Computational models developed. a, Geometry. b, Mesh. c, Cut view of the four computational models tested, where it is possible to observe the palate tissue regions. d, Boundary group faces for each of the three main components - palate, tongue and pacifier

Fig. 2

Evolution of the magnitude of the force exerted by the pacifier on the palate over two suction cycles (e), all the forces evolutions are almost superimposed, and von Mises stress distribution on the palate (presented in an occlusal projection) for all palate models at the peak of the second cycle (f)

Fig. 3

Evolution of maximum displacement magnitude for the right teeth. a, d, central incisor. b, e, Lateral incisor. c, f, First molar. The bottom row presents a zoom for the lower range of the displacement, to allow a better comparison of models 3T, 4T and 5T results

Fig. 4

Evolution of the magnitude of the force exerted on the right teeth for the 4 palate models studied. a, d, central incisor. b, e, Lateral incisor. c, f, Fist molar. The bottom row presents a zoom for the lower range of the force magnitude, to allow a better analysis of models 1T and 5T

Fig. 5

Vectors of the force, corresponding to the instant of the maximum force magnitude, for the palate models 1T and 5T (left) and 3T and 4T (right)