Lower third molars

Abstract

There has always been a debate whether to remove or leave asymptomatic mesioangular impacted lower third molars. The present short communication discusses the merit of prophylactic removal to avoid clinical complications in future and the consequences to second molars.

INTRODUCTION

Impacted third molars are the most common developmental conditions that affect humans. The impactions are defined in relation to the geometric angle of impaction such as mesioangular, distoangular, and horizontal, and these can be partial or completely buried.

The NICE guidance on wisdom teeth describes the complications that may arise from the surgical removal of wisdom teeth but does not describe its benefits.[1] Clinical decision-making should be based on the relative benefits and harms for the patient. The important question is what the risk of retained wisdom teeth is in future for development of any pathology if left untreated.[2]

This short communication presents some of the practical difficulties frequently encountered in decision making for removal of mesioangular impacted lower third molars that are in contact with second molar.

CLINICAL EVIDENCE

Mesioangular-impacted lower third molars, which are completely covered with mucosa, create a deficient gingival collar that is not fluid-tight along distal cementoenamel junction of second molar.[3,4] This makes the second and third molars vulnerable to caries and rarely resorption of second molar if left untreated in long run.

Case 1

A 60-year-old man was advised to leave lower left mesioangular third molar that was asymptomatic and clinically covered with mucosa. On subsequent visit, he had occlusal decay with left lower second molar and was treated with gold crown by his dentist 15 years back. On recent visit, his orthopantomogram (OPG) showed mesioangular impaction with deep decay and recurrent decay with his left second molar under the crown distally and was referred for removal of lower third molar [Figure 1]. The lower left third molar was removed under local anesthesia, and the patient was referred back to dentist to treat recurrent decay with second molar [Figure 2].

Figure 1.

Orthopantomogram showing decayed mesioangular left lower third molar and recurrent decay with second molar

Figure 2.

Orthopantomogram postoperative after removal of wisdom tooth

Case 2

A 24-year-old man was referred for removal of wisdom teeth. Clinically, all his wisdom teeth were impacted and were asymptomatic. OPG showed lower third molars were mesioangular [Figure 3]. He was treated under general anesthetics in day surgery, and all his wisdom teeth were removed. His post-operative OPG showed distal resorption of right second molar which is rare but can be seen [Figure 4].

Figure 3.

Orthopantomogram showing mesioangular impacted third molars

Figure 4.

Orthopantomogram postoperative showing distal resorption of right second molar

DISCUSSION

This is well-known that mesioangular lower third molar are the potential cause of decay, and rarely resorption is associated with second molar. This raises another question that routine postoperative OPG is a must post-operatively after surgical removal of wisdom teeth to substantiate the findings of caries or resorption with second molars.

There is sufficient literature, which has been published from time to time, to reinstate these finding but NICE guidelines has remained the same.[4] There are no stringent guidelines to suggest that these situations should be dealt with prophylactic removal of third molars to avoid complications in future. Current UK clinical Guidelines for management of lower third molars are against the prophylactic removal of asymptomatic healthy impacted teeth.[3]

NICE guidelines were first published in 2000; since then the surgical skills, armamentarium, and tools for surgical pre assessment have improved considerably in avoiding surgical risk. It is time for NICE to review these guidelines to improve management of these situations.[2,5]