## 1 Introduction  
Edentulism is defined as complete loss of the entire dentition [1]. Anatomically, edentulous jaws and maxilla are characterized by loss of the alveolar process [2]. A series of classifications that describe the morphology and severity of bone resorption of the edentulous ridges have been documented in the literature.  
In 1963, [PERSON] used a micrograph technique to describe a series of changes in shape and height that the residual ridge undergoes [3]. In general, changes in the shape of the alveolar process follow a predictable pattern. The loss of teeth invariably leads to residual alveolar ridge atrophy; this process has been described as irreversible, chronic, progressive, and cumulative [4,5]. With the use of conventional morphometry, in 1985, bone defects at the edentulous site were characterized into five classes on the basis of the volume of the remaining bone in comparison with its height [6]. Then, in 1988, a classification of edentulous jaws was developed on the basis of a randomized cross-sectional study of 300 dry skulls. It was stated that, while the shapes of the basal processes of the mandible and the maxilla remained relatively stable, the changes in the shape of the alveolar processes were significant in the vertical and horizontal axes, in both the anterior and posterior mandibular regions [7].  
In the 21 st century, a new study observed the natural course of edentulism using cadaveric material from medieval settlements to analyze the morphology of the residual ridge through conventional radiographs [8]. The authors of this new study found similar findings to the results of the aforementioned study when using the classification of bone atrophy described by [PERSON], [PERSON], and [PERSON] [3,7].  
Considering the multiple classifications of mandibular bone morphology that have been developed through conventional morphometric methods [3, 4, 5, 6, 7, 8, 9, 10], the anatomy of the interforminal mandibular region has not yet been fully described. Due to the growing interest in the mandibular interforminal region generated using endosseous implants [11,12], the analysis of variations in the mandibular interforminal morphology is of special importance, because it allows for the identification of potential risks or contraindications for surgery, especially the installation of implants in this particular region [13].  
The most common surgical errors are related to poor positioning or angulation of the implant, with subsequent aesthetic and biomechanical damage [14]. To avoid accidents and complications, correct pre-surgical planning is essential. The use of cross-sectional imaging, specifically CBCT, is recommended for planning implant placement [14].  
CBCT is the latest, cost-effective and accurate in vivo imaging technique that provides localization of relevant anatomical structures such as the mandibular incisive canal, lingual foramen, and mental nerve prior to the dental procedure, since it is recognized that surgical trauma is possible [15,16]. Thus, implant-related injuries represent a risk of damaging neuromuscular structures, particularly considering that they can cause sensorineural disturbance and pain [14,16]. Besides, CBCT allows clinicians to create and visualize the final result in a three-dimensional manner before starting the treatment in the interforminal region of the mandible, and to analyze multiple treatment scenarios until the optimal treatment plan is adopted [17,18].  
A better understanding of this anatomical region will facilitate planning of implant support prosthesis, protocols of bone drilling, and regenerative therapies. Therefore, the aim of this pilot study was to determine the morphogeometric patterns of the interforminal mandibular region from cone beam computed tomography (CBCT) scans in individuals with total mandibular edentulism.