Validation of a purpose‐built chewing gum and smartphone application to evaluate chewing efficiency

Summary Objectives To validate a purpose‐built two‐coloured chewing gum (Hue‐Check Gum®), and to test the accuracy of a custom‐built smartphone application for a colour‐mixing ability test to assess chewing function. Methods Fully dentate participants (28D‐group) and edentulous participants with implant overdentures (IOD‐group) were recruited. They chewed a Hue‐Check Gum®for 5, 10, 20, 30 and 50 chewing cycles, respectively. Maximum voluntary bite force (MBF) was assessed with a digital gauge. The specimens were analysed according to their colour mixture (variance of hue,VOH) with a validated software (VOH_scan) and a newly developed smartphone application (VOH_app). Results Participants segregated by dental state were significantly different regarding the number of occluding pairs of teeth, age andMBF.VOH_scan showed a negative logarithmic association with the number of chewing cycles, andVOHcould be predicted from chewing cycles,MBFand gender. The clearest discrimination between theIODand the 28D groups was observed for n = 20 chewing cycles; at this point,VOHwas distinguishably different with aP‐value < 0.0001. TheVOH_app was a very good predictor forVOH_scan with 0.80 < pseudo‐R2 < 0.83, depending on light exposure and measuring distance. There was, however, a systematic error in the accuracy of the app for inadequately chewed specimens. Conclusions The use of the two‐coloured chewing gum would provide a fast, simple and inexpensive method for the assessment of masticatory performance, which could be used in geriatric wards or in private practices without the requirement of specialised equipment or trained staff.