In addition, it also remains to be demonstrated how a potential compensatory mechanism might work, with one of the options being osseoperception [2, 18–23]. In this context, it is also important to consider the adaptation time needed after oral rehabilitation. Some studies have performed longitudinal evaluations of masticatory function for more than 3 years [24, 25]. However, there are limited data available on short-term adaptation to mastication, especially in the first months after being fitted with a prosthetic appliance. Although approximately 2 months are generally required for adaptation to a new removable denture, the time needed to adapt to a new implant-supported prosthesis has not been established [26]. Furthermore, adaptation is likely to be more difficult with full fixed implant prostheses [27].

In a functional magnetic resolution imaging (fMRI) study of patients with implants, it was demonstrated that punctate mechanical stimulation of oral implants activates both primary and secondary cortical somatosensory areas and was suggested that brain plasticity occurs when extracted teeth are replaced by endosseous implants [28]. In another fMRI study, it was suggested that the time after tooth extraction may affect neural plasticity, which in turn can influence osseoperception, with the amount of time possibly being an indicator for prosthetic treatment planning [23]. The lack of peripheral feedback mechanisms in patients with implant-supported full fixed prostheses may lead to a lack of control over the biting force [3, 29]. Such control is needed for refinement and control of the biting force for various types of food [7, 30–32]. While patients with implant-supported bridges are able to bite food with varying levels of hardness, it could be questioned whether they are able to differentiate between the hardness variations and thus apply an adapted chewing pattern [33]. Although some studies have demonstrated the tactile function of patients with oral implants [18, 19], the perception of food hardness is yet another sensory function that should be evaluated in order to obtain more information on modulation and masticatory adaptation. However, there have been few studies on this issue. Although adaptation to food texture during mastication by dentate subjects has been tested [34], it has not yet been followed up in patients receiving implant placement. In a recent cross-sectional study, mastication adaptability in patients with implant-supported bridges was assessed with soft and hard food models using an electromyogram (EMG) [7]. Patients with implants showed a significantly weaker increase in EMG activity with increased food hardness. In addition, muscular work performance (bite-force ratio and muscle activity) was found to be lower in patients with implants [35]. Furthermore, less coordinated masticatory muscle activity was found in patients with implant-supported prostheses [36].