The Inferior Alveolar Nerve (IAN) is a branch of the mandibular nerve (V3), the third division of the trigeminal nerve (cranial nerve V). It enters the mandibular foramen, runs through the mandibular canal, and exits through the mental foramen, giving rise to the mental nerve[1].

Due to its anatomical location, the IAN is at risk during various dental and surgical procedures. Injuries to this nerve can lead to temporary or permanent sensory disturbances, such as paresthesia or numbness. This article aims to educate patients by analyzing 100 clinical cases and providing insight into the anatomical, procedural, and outcome-related aspects of the IAN.

IAN courses in the canal to supply somatic afferent fibres to the gingiva anterior to the premolar, lip and chin. Detailed knowledge of the position, course and morphology of the mandibular canal is of utmost importance for performing various surgical procedures such as dental implant placement, periapical surgery, osteotomies, bone graft harvesting, bone plating procedures and administration of local anaesthesia.[2] During embryonic development and maturation, three IANs fuse to form a single nerve.[3] As a result of the abnormal interaction of tissues during embryonic development, the morphological alteration of the mandibular canal occurs.

In some cases, IAN runs inferior to the lower margin of the mental foramen. After giving off the incisive branch, it curves superiorly, turns posteriorly and reaches the mental foramen to continue as the mental nerve. The part of the mental nerve anterior to the mental foramen caused by this altered course of the IAN is called the mental nerve loop/anterior loop of the mental nerve[4-5].

This is observational study of 100 patients was conducted at Daswani Dental College & Research Centre, Kota for 01 Year. Data was collected on:

• Demographics
• Type of dental procedure performed
• Imaging modality used
• Incidence of IAN-related symptoms
• Management and recovery timeline

Inclusion Criteria:

• Patients aged 18–70
• Underwent procedures involving the lower jaw (extractions, implants, or nerve blocks)
• Provided informed consent
• Mandible fixation was included

Exclusion Criteria:

• History of facial trauma was excluded
• Pre-existing neurological disorders
• Incomplete records.

Table 1: Demographics of Patients

Table 2: Procedures Performed

Table 3: Incidence of IAN-Related Symptoms

Transient Numbness (<2 weeks): 12 cases were reported, accounting for 12% of the total study population. This indicates short-term sensory loss that resolved within two weeks.

Persistent Numbness (>2 weeks): 6 cases, making up 6% of the total. These cases experienced numbness that lasted longer than two weeks, suggesting more prolonged or possibly permanent nerve involvement.

Tingling/Burning Sensation: Reported in 4 cases (4%), reflecting altered or uncomfortable nerve sensations without full numbness, commonly known as paresthesia or dysesthesia.

Total IAN Involvement: Overall, 22 cases (22% of the total population) showed some form of IAN-related symptom, whether transient or persistent.

Table 4: Imaging Used

Panoramic X-rays were the most frequently used imaging modality, followed by CBCT and periapical radiographs. The data suggest that while broad screening with panoramic imaging was standard, more detailed or focused imaging was used selectively based on clinical need.

Table 5: Recovery Timeline

The majority of patients (18 out of 22, or 82%) recovered within four weeks. A small number experienced prolonged symptoms, and only one patient showed signs of long-term or unresolved nerve issues. The data suggests that while IAN symptoms are relatively common, they are typically temporary.

The IAN’s proximity to the roots of the mandibular molars and the implant osteotomy sites makes it highly vulnerable during surgical procedures. A thorough understanding of its course is essential to avoid complications[6-9].

Symptom Incidence: In this cohort, 22% of patients reported IAN-related symptoms postoperatively. The majority experienced temporary numbness or paresthesia, resolving within one month.

Use of CBCT helped in precisely locating the mandibular canal in high-risk cases, such as implants and third molar surgery. The use of panoramic radiography alone may underestimate nerve proximity, leading to avoidable complications[10-13].

Most IAN disturbances were transient, consistent with literature stating that 90% of injuries resolve spontaneously. Persistent symptoms in 1% of cases were referred for microsurgical consultation.

Patients often underestimate the risk of nerve injury. Clear pre-operative counseling and informed consent are essential, especially for high-risk procedures[14-16]. The IAN has shown to have morphological differences before entering the mandibular canal, as well as during its path within the mandibular canal. Significant variations are found in canal morphology. The most commonly discussed variations are the bifid canal, accessory canal, alteration in canal course and number of foramina at entry and exit of IAN.[17] As previously stated by Pyun et al., in 2013, these supplementary communications may supply additional innervation to the mandibular teeth and adjacent soft tissues and may be involved in inadequate dental anaesthesia due to the possibility for nerve impulse collateral transmission.[18].

The Inferior Alveolar Nerve is vital for the sensory innervation of the lower face and is at risk during many common dental procedures. In this study of 100 patients:

• 22% experienced IAN-related symptoms
• Most cases were mild and resolved within weeks
• CBCT imaging significantly enhanced procedural safety

Patient awareness and dentist vigilance are critical in reducing nerve injury risk. This article serves as both a clinical resource and educational tool for patients and professionals.

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