Hemorrhage Secondary to Interforamina Implant Surgery: Anatomical Considerations
Authors: Gill Prabhsimrat , Willmore Katherine , Wilson Tim , Perinpanayagam Hiran , Galil Khadry 
Published: November 2023

Introduction

Dental implants are commonly used to replace missing teeth in the anterior mandible. However, this area is richly vascularized by the sublingual and submandibular arteries, which are branches of the lingual and facial arteries respectively. The pathways of these arteries are variable, as evidenced by the variability of the lingual foramina that they traverse through. These foramina are located in the interforaminal area, which is on the lingual surface of the anterior mandible where the genial tubercles are found. Placement of implants in the interforaminal area can lead to hemorrhage, the results of which can lead to serious complications including swelling of the submandibular floor and tongue, as well as obstruction of the airways.

Objectives

The objective of this research was to characterize variations in the sublingual and submandibular arteries. Secondarily, we will enumerate and describe the lingual foramina through which these arteries pass.

Methods

The study was performed on both dry mandibles and cadaveric samples. To characterize the variability in the lingual foramina, 50 dry mandibles were used and measurements of the lingual foramina in the interforaminal area were recorded. These measurements included the diameter of the foramina, the location of the foramina relative to the superior and inferior borders of the mandible, and their frequency of occurrence bilaterally on the mandible. The location of foramina was measured as a ratio of the distance from the superior border of the mandible over the total height of the anterior mandible, in order to account for differences in mandibular heights between specimens.

To characterize paths and branching patterns of the sublingual and submandibular arteries, 15 cadaveric heads will be dissected. The arteries will then be examined for variations in their branching, asymmetry, and point of entry into the mandible (distance from superior portion of mandibular bone).

Results

Of the lingual foramina measured, 51% (20/39) were clustered 55–65% below the internal superior surface of the mandible. However, there was large variation in this data, with lingual foramina occurring anywhere from 30% below the internal superior border of the mandibular bone to 70% of the distance below. Additionally, 26/39 (67%) of foramina were found on the lower half of the mandibular bone surface.

Examination of foramina symmetry suggest significantly more were found on the left side (Left = 2.3 ± 1.1) as opposed to the right (1.4 ± 1.1) (P=0.021).

Conclusion

Within the limits of this study more foramina exist on the left half of the lingual side of the anterior mandible than on the right which could imply a greater blood supply to that region. Further investigations are being carried out to determine the distribution of the sublingual and submandibular artery branches in the interforaminal area. Possible avenues will use CBCT or ultrasound in patients to define and locate these arteries as they enter the mandible, as this is difficult to see in embalmed cadavers. Enhanced knowledge of the arterial supply and variation of this area of the mandible will guide clinical practice in the future and can help avoid complication.