Measurement of Distance Between the Mental Foramina using ConeBeam Computed Tomography: A Pilot Study with a Possible Method for Planning Mandibular Implants

Abstract

Objective: To identify the average number of dental implants that can be placed in the lower anterior region to support a fixed mandibular prosthesis based on the distance between the mental foramina, using a cone beam computed tomography (CBCT) scan through a new method of measurement. Material and Methods: Eighty-two CT scans from a total sample of 1,465 exams were selected. The method to measure the space between the foramina was developed using the BlueSky Plan3 software in Dicom format and the axial reconstruction views were chosen for measurements. Descriptive analysis of data was conducted categorical variables were compared using the χ2 test (p <0.05). Results: The mean age of individuals who underwent the scans was 63.51 ± 9.49 years old with a minimum and maximum age of 40 and 86 years old, respectively. The mean linear measurement between the foramina was 40.52 ± 3.92mm. In males the mean distance was 41.93 ± 3.98 mm, and for females it was 39.99 ± 3.80mm, with a significant difference between the means (p = 0.043). There was no positive association between the presence of the anterior loop and gender (p = 0.719). The results showed that the vast majority of subjects (n = 80) could be rehabilitated using a protocol with 4 implants of 3.3mm diameters. Conclusion: Seventy-seven patients would be able to receive protocols of 4 implants with diameters of 3.75 or 4.0mm, and only 4 subjects would be able to be rehabilitated with 6 implants with diameters of 3.75 mm according to the protocol originally described by Brånemark.

The location of the mental foramen in relation to the biometrics of the lower dentition and mandibular arch: A cross-sectional study

“…36 However, there have been a pause in such study until the revisits by several authors in the millennium. 5,13,15,37,38 13 The current finding is closer to the measurement reported by Guo et al (2009) and is in agreement with the measurement reported by Vane Swetah & Jayanth Kumar (2019). 15,37 Difference in measurements in the studies performed after the millennium against those reported in the 1930s may be related to the technique used, or difference in the population whereby the current samples may have benefitted from better living condition and nutrition.…”

“…They found that a universal treatment plan cannot be followed in their Indian subjects due to the short interforamina distance of 38.9 mm in their subjects. In agreement with them, Marieiro et al (2017) reported most of their subjects could be rehabilitated using a protocol with 4 implants of 3.3mm diameters. In contrast, the finding of current study suggests that Malaysian Mongoloids had sufficient space to receive the so-called OD-5 prosthesis, i.e., five implants rigidly joined with a bar.…”

“…In contrast, the finding of current study suggests that Malaysian Mongoloids had sufficient space to receive the so-called OD-5 prosthesis, i.e., five implants rigidly joined with a bar. 38 Lastly, while this study did provide useful metrical and morphological parameters of the mandible of Mongoloid Malaysians, there were some limitations due to insufficient CBCT scans to undertake any age-related changes in different age groups. This study does present some limitations, including the insufficient CBCT scans recruited for the different age groups of adult Malaysians to recognize any age-related changes, and the facts that all subjects were dentate.…”

“…In the case of Bhargava et al (2016) and Bastião Marieiro et al (2017)'s findings, their subjects were fully edentulous. 5,38 In addition, the method of obtaining linear measurement used by appear to cause shorter inter-foramina distance. 38 In edentulous mandible, the mandibular arch form, arch size, and the inter-foramina distance are factors that influence the selection of size and position of implants and the prosthetic design (fixed or removable).…”

“…5,38 In addition, the method of obtaining linear measurement used by appear to cause shorter inter-foramina distance. 38 In edentulous mandible, the mandibular arch form, arch size, and the inter-foramina distance are factors that influence the selection of size and position of implants and the prosthetic design (fixed or removable). 5 Bhargava et al (2016) proposed a classification system that incorporated the inter-foramina distance in addition to the generally accepted classification system based on the vertical restorative space.…”