Evaluation of Position of Mental Foramen in Dentulous Population by Digital Panoramic Radiography

ABSTRACT

Need for the Study:

The mental branch of the trigeminal nerve, which supplies sensation to the lower lip, originates in the mandibular canal, making it an essential anatomical structure for dentists and oral surgeons to access. It is not well known that there is a spectrum of normal that includes variants in which there may be more than one nerve entry site, which means that if the mental foramen is not protected, normal feeling in the lower lip may be lost permanently. The diagnostic value of global radiographic landmarks like the mandibular trench and the dental foramen in identifying skeletal problems has been investigated.

Materials and Methods:

Four hundred patients over 40 who fit the inclusion/exclusion criteria were chosen. Patients were recruited from Vananchal Dental College and Hospital, Garhwa’s Out Patient section for Oral Medicine, Diagnosis, and Radiology. The following patients with their consent are subjected for digital orthopantomography (Cephalometric Device for Rotograph EVOD Ref 930790001, SN 14112930, Villa Sistem Medical) and the captured images are then interpreted for the variations in mandibular canal.

Result:

The results of our study are as follows:

• In this study, the mean age of the subjects was 47.27 years, with a range of 40–75 years

• Majority of cases were females (53.75%) and 46.25% were males.

• The top of the residual ridge, located between the mental foramen and the mandibular canal, is clearly visible to all observers (grade I).

• Only 1.75% of the people surveyed had a bifid canal, despite the fact that the majority of the people surveyed had a single mandibular canal on both sides (98.25%).

• Right side mean was 18,682.017, whereas left side mean was 16,331.851; nevertheless, this difference was not statistically significant (P = 0.0860 NS).

Conclusion

The dental foramen was located close to where the mandible and the area housing the next premolar met. These findings may be utilized to improve the safety of peri-apical surgical procedures. Therefore, it is therapeutically relevant to get insight into the structural alterations of the mental foramen and locate its location in preoperative radiological scans.

INTRODUCTION

You may locate the dental foramen, or opening, near to where the dental canal shuts on the parallel side of the jaw. It is typically seen in the anterolateral region of the mandible.[1] The tough cortical plate of the buccium completely encloses this foramen. The dental nerve palpably innervates the buccal vestibule, gingiva mesial, and the major mandibular molar. A foramen normally measures 4.6 mm in width and 3.4 mm in height on the parallel side of the jaw.[2] Finding the dental foramen requires taking into account the precise sedation of the sharp terminal ends of the mediocre alveolar nerve. After medications, such as peri-apical surgical treatment, tooth extraction, blister or cancer enucleation, and so on, harm to the dental group may occur, leaving the region innervated by the nerve numb or shivering.[3] It is also useful for forensics and oral pathology professionals when trying to make sense of a patient’s anatomy by use of recognizable features.[4]

Panorama radiography is often used by dentists because it provides a more complete image of the oral cavity, jaws, and temporomandibular joints than conventional radiographs.[5-7] When doing surgery or administering local anesthesia in the craniofacial region, it is important to remember the location of the neurovascular bundles in the supraorbital, infraorbital, and mental foramina. If one is familiar with the structure of the nerve and blood vessel bundles, damage to them can be prevented.[8] Panoramic radiography produces a 2D picture with no magnification in the bucco-lingual or vertical–horizontal planes. The oral anatomical features may be more clearly seen on a computed tomography scan.[9] Panoramic radiographs, on the other hand, are less costly, simpler to take, and more straightforward in their interpretation.[10] Digital panoramic radiography enhances the already high picture quality of traditional panoramic radiography.

In a demographically representative test of Northeast Indians, this investigation used comprehensive radiography to examine the connection between the location of the mandibular trench and the dental foramen.

MATERIAL AND METHODS

The investigation used 400 modern all-encompassing radiographs that complied with the requirements from the radiology and oral medicine branch’s database. These radiographs ranged in age from more than 40 years old and were of both sexes (200 male and 200 female).

Inclusion criteria

1. Age 40 and higher.

2. Everyone with first and second molars are present.

3. Excellent angulation and contrast in the radiographs.

4. X-rays that do not include any radiolucent or radiopaque lesions in the lower arch and do not exhibit any exposure or processing errors.

5. All genuine radiographic MFs (the topmost one), closest to the mandibular canal, were included in the analysis.

Exclusion criteria

1. Radiographs of patients with drifted, crowded, and spaced lower teeth.

2. Previous orthodontic treatment.

3. Digital panoramic radiographs where the MF could not be identified.

The following patients with their consent are subjected for digital orthopantomography (Cephalometric Device for Rotograph EVOD Ref 930790001, SN 14112930, Villa Sistem Medical) and the captured images are then interpreted for the variations in mandibular canal [Figure 1]. A formal approval letter from the Head of the Department was obtained to carry out this study.

Figure 1.

Orthopantomograph of the patient before tracing

It was determined by measuring the following factors in an edentulous mandible: the health of the mandibular canals on both sides of the jaw.

Grade 0: The crest of the residual ridge above both the mental foramen and mandibular canal. [Figure 2].

Figure 2.

Measurement from the marginal ridge to the mental foramen

Grade I: With or without a resorbed border, the peak of the residual ridge may be located above the mandibular canal and the mental foramen.

Grade II: Ridge across the mental foramen and mandibular canal; this may or may not have lost part of its boundary over time.

Grade III: The bone around the mandibular canal and the mental foramen had been worn down.

In order to do the necessary statistical analysis, version 17.0 of SPSS was employed. Analysis of age and gender variations in the anterior–posterior orientation, shape, and symmetry of the mental foramina was performed using frequency distributions, cross-tabulations, and the Chi-square test. If the P-value of the data was less than 0.05, then it was considered to be significant.

RESULT

The Oral Medicine and Radiology Division carried out this cross-sectional research to investigate the link between the position of teeth and the size of the mandibular canal and mental foramen in both dentate and edentulous persons using excellent all-encompassing radiography. A total of 400 computerized full-body radiographs of patients aged 40 or older from both sexes were selected from the radiology and oral medicine division’s information base (185 men and 215 women) [Table 1].

Table 1.

Age-wise distribution of subjects

Age (years)	Number	Percentage
40-50	291	72.75
51-60	85	21.25
61-70	20	5
>70	4	1
Total	400	100

This table depicts that the maximum number of patients (72.75%) were in 40-50 years of age group followed by 21.25% 51-60 years, 5% 61-70 years, and minimum only 1% subjects have more than 70 years of age groups

The results of our study are as follows:

• In this study, the mean age of the subjects was 47.27 years, with a range of 40–75 years [Table 2]

• Majority of cases were females (53.75%) and 46.25% were males [Table 3]

• The top of the residual ridge, located between the mental foramen and the mandibular canal, is clearly visible to all observers (grade I)

• Only 1.75% of the people surveyed had a bifid canal, despite the fact that the majority of the people surveyed had a single mandibular canal on both sides (98.25%) [Table 4]

• Right side mean was 18,682.017, whereas left side mean was 16,331.851; nevertheless, this difference was not statistically significant (P = 0.0860 NS) [Tables 5 and 6].

Table 2.

Mean age of subjects

Age (years)	Subjects
Mean	47.27 years
SD	7.384 years
Minimum	40 years
Maximum	75 years
Range	40-75 years

According to the above data, the study’s participants had an average age of 47.27 years, with a minimum age of 40 and a maximum age of 75

Table 3.

Gender-wise distribution of subjects

Gender	Number	Percentage
Male	185	46.25
Female	215	53.75
Total	400	100
Male: Female	0.86:1

This table depicts that the majority of cases were females (53.75%) and 46.25% were males. Male-to-female ratio was 0.86:1

Table 4.

Position of mandibular canal in right and left side in subjects

Position of mandibular canal	Right side	Left side
Grade 0	400	400
Grade I	0	0
Grade II	0	0
Grade III	0	0”

According to the data in the table above, the top of the residual ridge is located above the level of the mental foramen in all participants (grade I)

Table 5.

Number of mandibular canal in right and left side in subjects

Number of mandibular canal	Single	Bifid	Total
Right side	393	7	400
Left side	393	7	400

This table depicts that the mostly single mandibular canal (98.25% each) in both sides; Only 1.75% subjects were have bifid canal in this study

Table 6.

Position of mental foramen in right and left side in subjects

Position of mental foramen	Right side	Left side	P
Mean±SD	1.868±2.017	1.633±1.851	0.0860 NS

This table represents the position of mental foramen from crest of residual ridge. The mean value was 1.868±2.017 in right side and 1.633±1.851 in left side, but statistically nonsignificant P=0.0860 NS

DISCUSSION

The sole noninvasive option for treatment planning involving the mandible is radiography. Screening, diagnosing, and deciding on the optimal surgical strategy[11] are all typical applications of panoramic radiography. As the jaw develops, the mental foramen’s position could shift.[12] An all-encompassing X-ray might be helpful to dentists when implanting mental posts by identifying the precise locations of the mandibular trench and the mental foramen.[13]

The lower lip is supplied by nerves that exit the skull via a hole called the dental foramen.[14,15]

However, if the mental foramen is located beyond the peri-apical radiograph’s film’s edge, its location will not be seen.[12] As the mental foramen may be obscured by the roots of permanent teeth during mixed dentition, this age group was chosen for the research.[2] Though increasing bone density might make seeing the mental foramen more challenging, our research shows that it is clearly recognizable in panoramic videos.[2]

In this research, participants’ ages ranged from 40 to 75, with a mean age of 47.27 years. According to research by Muhammed Ajmal (2014),[16] when comparing edentulous men and women, the distance between the top of the alveolar ridge and the top of the mental foramen was shown to be significantly greater in the former. This statistic sharply dropped as people became older.

Babshet et al. (2015)[17] observed a posterior migration of the foramen with increasing age; they discovered no statistically significant relationship between foramen location and chronological age.

The current research demonstrated a male-to-female ratio of 0.86:1. It was discovered by Amorim et al. (2008)[18] that the MF–MS values of male mandibles were greater than those of female mandibles, and that the MF–MS values of dentate mandibles were greater than those of edentulous mandibles (P = 0.05) when comparing the two sexes.

Mandibular edentulism may be connected with certain alterations in the form of the mandible, as was established by Chrcanovic et al. (2011).[19] Mandibular architecture is more influenced by mental health than by gender.

Position on either the right or left side was shown to have no significant association with either age or sex (P > 0.005) by Babshet et al. (2015).[17]

In individuals with teeth, the mental foramen was found below the median of the skull. The dental foramen of the mandible of edentulous adults shifted, becoming closer to the top line, as a result of bone resorption. When implementing this finding in clinical practice, it will be necessary to take the patient’s age and dentate status into consideration, among other logical criteria.

CONCLUSION

The present study reveals valuable insight on the information concerning the type and position of mental foramen in the Jharkhand population. The study suggests that clinicians should carefully identify mental foramen, thus minimizing complications during implant, orthognathic surgery, and treatment of maxillofacial injuries.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.