Present Status in Polymeric Mouthguards. A Future Area for Additive Manufacturing?

Abstract

<jats:p>Athletes from contact sports are more prone to orofacial injuries because of the exposure to possible shocks and collisions derived from physical proximity. The use of protector polymeric mouthguards proved to be useful in the prevention of the described injuries. There are different types of mouthguards with varying ranges of protection and prices, but they are all made from polymers and share the same propose: to absorb and dissipate the impact energy resulting from the shocks. As they are used inside the mouth, they should not impair breathing and speaking nor compromise the comfort of the athlete. However, the ideal mouthguard is yet to be created. The choice of the most appropriate polymeric material and the standard required properties have not yet been reported. Regardless of the numerous studies in this field, normalized control parameters for both material characterization and mouthguard fabrication are absent. This paper aims to present a review of the current types of available mouthguards and their properties/characteristics. Moreover, a detailed description of the most common polymers for the fabrication of mouthguards, together with the manufacturing techniques, are discussed.</jats:p>

Mouthguard Use Effect on the Biomechanical Response of an Ankylosed Maxillary Central Incisor during a Traumatic Impact: A 3-Dimensional Finite Element Analysis

“…The beneficial effect of wearing the mouthguard for sound tooth has been already reported in the literature using three-dimensional [ 11 , 13 , 14 ] and bi-dimensional analysis [ 8 , 16 ]. All of them showed a reduced stress magnitude for dentin and enamel [ 8 , 11 , 13 , 14 , 18 ]. For bone tissue [ 8 , 11 , 13 , 20 ], the MG can also reduce the stress peak at the impact momentum.…”

“…In sequence, the meshes were generated through the convergence test until obtaining a finite number of nodes and elements for the models. The materials were considered isotropic, homogeneous, and linearly elastic and the mechanical properties used in the simulation are summarized in Table 1 [ 8 , 18 , 24 , 25 , 26 , 27 , 28 , 29 ]. The solids presented perfectly bonded contacts, except the mouthguard that was considered frictionless.…”

“…Regarding the mouthguards’ manufacturing, polymers are, unquestionably, the appropriate class of materials for the production of mouthguards [ 18 ]. Nowadays, ethylene vinyl acetate (EVA) copolymer is the most common polymer used for it.…”

“…Nowadays, ethylene vinyl acetate (EVA) copolymer is the most common polymer used for it. Polyolefin, polyvinyl chloride, polyurethane, acrylic resin, silicone rubbers, and even polyetheretherketone are some examples of materials evaluated in the past as possible to be used; however, none of them behaves as well as EVA for this indication [ 18 ]. In the future, the computer-aided design and computer-aided technology as subtractive manufacturing process [ 19 ] and the 3D-impression as additive manufacture [ 18 ] will provide new possibilities of materials usage and design for mouthguard definition and customization [ 18 , 19 ].…”

Biomechanical Behavior Evaluation of a Novel Hybrid Occlusal Splint-mouthguard for Contact Sports: 3D-FEA

“…In this model, the HMG contained two distinct and juxtaposed structures formed by a rigid occlusal splint and with 3 mm axial flanges made of flexible polymer (Figure 2). As control, a conventional custom-made mouthguard (MG) design was previously reported in the literature [7,8] and created presenting 4 mm thickness reported as the ideal thickness for this device [20]. For both the MG and HMG designs, a Boolean difference procedure has been performed to create the inner portion with the occlusal impression.…”