In the permanent dentition, the third molars (colloquially termed wisdom teeth ) are, by and large, the most varied and are most likely to get impacted. Although often advised for extraction, the perpetual question of the medical necessity for removal of these teeth has been contested in the dental literature. An astute clinician should prioritize patient well-being and gauge the risk/benefit ratio while considering surgical extraction. As with any dental procedure, a thorough diagnosis and detailed workup, including the chief complaint, medical history, and clinical examination, is paramount. This evaluation typically involves measuring probing depths and attachment levels around both the third molar and the adjacent second M, as well as conducting a thorough radiographic assessment. Panoramic radiograph is a simple imaging modality, as it provides a reliable overview of the hard tissues of the jaws.

The most crucial factor here is the decision the clinician has to make as to whether or not to extract the third molars. In this article, we explore the most recent literature regarding the necessity for such removal.

The most important factors that a clinician should consider in making such a decision are the risks of the surgical procedure and patient preferences. Much similar to any other surgical procedure, the risk-benefit ratio should be carefully explored in deciding whether to extract or retain a third molar.

Ancestral populations relied on a diet consisting of tough, fibrous plant material, roots, and uncooked meat, which required significant masticatory effort. Third molars provided the necessary additional grinding surfaces to process these foods efficiently. The evolutionary trajectory of the human jaw has seen a reduction in size over millennia, attributed to the changes in the diet, cooked versus raw food, and the utilization of cutlery to reduce the food portion size. These advancements reduced the need for extensive mastication, resulting in smaller jaws with limited space for the full complement of teeth, including third molars. The greatest reduction in size was the total mesiodistal length of the tooth-bearing areas of the arches.

In general, jaw size is primarily determined by function, whereas the primary determinant of tooth size is genetics. This mismatch between jaw size and total mesiodistal dimension of the teeth may lead to impacted third molars.

Third molars are of significant interest in dentistry because of their highly variable developmental patterns and complex interactions with adjacent teeth and oral structures. There are various existing myths prevalent about third molars, which are summarized in Fig. 1 . Unpredictable eruption patterns and the potential for impaction of third molars often present diagnostic and management challenges in clinical practice. However, there is an argument over the removal of asymptomatic third molars. It is important to consider that while third molars can remain asymptomatic, they are not necessarily disease-free. Therefore, regular evaluations, including radiographic assessments, are essential to determine the appropriate management strategy, which may include monitoring or extraction based on individual risk factors and overall oral and systemic health. A contentious belief is that third molars may contribute to late anterior crowding of the mandibular incisors. However, impacted third molars do not significantly impact the development of incisor crowding. According to the recent reporting, orthodontists favored retaining asymptomatic third molars. For patients who plan to undergo orthognathic and other reconstructive surgeries, it used to be a standard approach for managing impacted third molars to extract them several months before the procedure. However, this is not practiced routinely anymore. A frequently reported pathology associated with third molars is pain, with prevalence rates ranging from 6% to 55%. The incidence of complications such as cellulitis and osteomyelitis has been cited at approximately 4.5%. Other conditions associated with impacted third molars include functional disorders, such as interference with occlusion, cheek biting, masticatory dysfunction, limited mouth opening, and temporomandibular dysfunction. Despite the distress and discomfort caused by these conditions, there is no evidence for any etiologic association. The prevalence of periodontal disease with probing depth exceeding 4 mm has been reported to range from 30% to 62% for retained third molars and 16% to 51% for the second M. Determinants such as age and the duration of retention of third molars have a significant relation to the incidence of periodontal diseases. The prevalence of periodontal disease associated with the retaining third molars has been reported to be significantly higher in the mandible compared to the maxilla. There is supporting evidence that establishes the presence of periodontal disease or pericoronal disease in the third molar areas, and suggests that the problem is persistent and progressive but may improve following the extraction of the teeth. Plaque scores and gingival indices, which remain as 2 accepted criteria for determining the status of oral and gingival health, have been shown to increase in teeth adjacent to partially impacted third molars. The incidences of external root resorption of the molar adjacent to retained third molars have ranged between 0.5% and 50%. The assessment of certain possible entities related to retained third molars, like external root resorption, will require 3-dimensional radiographic evaluation using cone beam computed tomography (CBCT). However, implementing this in every clinical practice or research study has its difficulties. Contradicting results were reported regarding the difference in prevalence between the mandible and the maxilla. The risk is increased in cases of partial eruption and cases of mesial inclination for both maxillary and mandibular third molars. The patient’s age, impaction depth, and inclination have been the decisive factors in the incidence of external root resorption. Clinicians play an important role while extracting third molars impacted vertically, horizontally near the angle of mandible. In such cases, risk and benefit evaluation, surgical expertise, and evaluating the bone volume is a must.

Myths about third molars within the dental community and the general population. ^,,,

In contrast to the agreement on indications for the surgical management of symptomatic impacted third molars, the removal of asymptomatic third molars remains controversial. Table 1 depicts various indications and relative contraindications for third molar extractions. The sequelae of third molar extractions are discomfort, pain, inflammation, ecchymosis, limited mouth opening, infection, and hematoma. Impairment to the neuronal structures may occur. The chances of future pathologies remain unpredictable; thus, the decision to manage an impacted third molar conservatively is debatable. Several guidelines have been published regarding the nonsurgical management of asymptomatic impacted third molars. An important perspective to consider is that asymptomatic third molars are not always disease-free. While monitoring is always required for retained third molars to detect possible entities like caries, periodontal pathologies, root resorption of the second M, cysts, and tumors. Clinical and radiographic methods used in several studies to evaluate the pathology are deficient. The retained mandibular third molars were significantly more prone to caries compared to the maxillary third molars. Also, the risk of caries of the adjacent molar in the presence of retained impacted third molars was evident. This is mainly caused by the difficulty of maintaining proper oral hygiene around the retained tooth and the accumulation of plaque. Currently, there are two fundamental approaches for managing impacted third molars. Firstly, the retention of an impacted third molar intentionally until there are symptoms or evidence of pathology, such as distal surface caries. This is known as the nonintervention or third molar retention technique. Whereas the alternative technique necessitates removing the impacted third molar before symptoms and pathologic indicators appear. This is known as preventive or interceptive removal. Other scenarios where the impacted tooth is adjacent to vital structures like the inferior alveolar nerve, a coronectomy is opted. This technique minimizes the chances of inferior alveolar nerve injury, lingual nerve injury, and dry socket, compared to conventional extraction, with no significant difference in infection rates. However, it has a specific failure rate and a higher likelihood of requiring additional surgery. Clinicians should weigh the benefits and drawbacks of both techniques and adapt their choices accordingly.

Commonly reported complications of third molar extraction include alveolar osteitis, infection, inferior alveolar nerve or lingual nerve involvement, bleeding, hematoma, temporomandibular joint dysfunction, and jaw fracture. Recent advances in oral and maxillofacial surgery integrate minimally invasive techniques and AI-driven tools to enhance personalized, multidisciplinary care. Artificial intelligence and machine learning models, particularly in the surgical management of third molars, have shown promise in accurately assessing the relationship between the third molar and the neuronal structures, such as the inferior alveolar nerve and the lingual nerve, improving diagnostic precision and patient outcomes. Considering the potential complications of third molar surgeries, certain relatively recent trends and philosophies have emerged. Currently, surgeons use a range of methods to minimize complications ( Table 2 ). These include judicious use of analgesics, steroid therapy, antibiotics, flap designs, sutures, drains, ozone therapy, cryotherapy, platelet-rich plasma (PRP), platelet-rich fibrin, piezoelectric surgery, and lasers. Although advancements have greatly diminished complications following third molar surgery, it is essential to consider various contributing factors during the treatment planning process. Various factors that contribute to making the surgical procedure difficult or less difficult are depicted in Figs. 2 and 3 .

Factors contributing toward making third molar extractions less difficult. (Class 1 ramus- The space between the ramus and the second M is larger than the mesiodistal diameter of the second M. Class A depth- The occlusal plane of the third molar is as high as that of the second molar.)

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