Characterization of mouth-formed mouthguards: thermal performance

This study examined whether the thermo-modeling process suits the thermal properties of the material constituting mouth-formed mouthguards (MGs). Five mouth-formed MGs were compared: four commercially available MGs (SDI™, Gel Nano™, Opro Shield Gold™, and Kipsta R300™) and one prototype. Differential scanning calorimetry was used to determine melting (T(m)) and crystallization (T(c)) temperatures and specific fusion and crystallization enthalpies (∆H(f) and ∆H(c) (J/g)). MGs were modeled with recording of vestibular flange and occlusal cushion temperatures (Toccl). Tm ranged from 45.3°C to 53.0°C and Tc ranged from 40.9°C to 48.2°C. Specific heat of fusion ranged from 40.2 J/g to 62.0 J/g. Toccl was higher than Tm for all MGs except Kipsta R300™. Guidelines provided by manufacturers may not be adapted to thermal properties of the MG material. To ensure proper thermomodeling, heating and biting durations should be adjusted.