Characteristics and dimensions of the infraorbital canal: a radiographic analysis using cone beam computed tomography (CBCT).

PURPOSE: To analyze morphological characteristics and dimensions of the infraorbital canal-groove complex using cone beam computed tomography (CBCT), and to evaluate its relationship with adjacent anatomical structures. METHODS: This retrospective study included CBCT scans of 100 patients taken between January and May 2014. Linear measurements of the infraorbital canal (IOC), the infraorbital groove (IOG) and the infraorbital canal-groove complex (IOC/G) were performed. Morphological variants of the IOC related to the maxillary sinus were classified into three types depending on the extent of protrusion of the canal into the sinus. Angles between the IOC and specific landmarks were measured to determine the direction of the IOC relative to the axial (A-ant) and sagittal (A-horiz) planes. RESULTS: A total of 127 IOCs were analyzed. The mean length of the IOC/G was 29 ± 3.0 mm. This value comprised the mean distances of the IOC (24.4 ± 2.9 mm) and the IOG (4.6 ± 1.7 mm). For the different types of IOC morphology, Type 1 (IOC embedded in maxillary sinus roof) was the most common (n = 87, 68.5%). The mean angles of A-ant and A-horiz measured 48.9° ± 7.5° and 20.3° ± 7.9°, respectively. CONCLUSION: Knowledge of the IOC/G morphology and its variants is important for the prevention of infraorbital nerve injury due to anesthesia or surgical interventions in this area. The presented data of anatomical characteristics of the IOC/G could be helpful for the planning of surgeries in the maxillary region by means of CBCT imaging.

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

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 and MBF. VOH_scan showed a negative logarithmic association with the number of chewing cycles, and VOH could be predicted from chewing cycles, MBF and gender. The clearest discrimination between the IOD and the 28D groups was observed for n = 20 chewing cycles; at this point, VOH was distinguishably different with a P-value < 0.0001. The VOH_app was a very good predictor for VOH_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.