Surgical removal of a third molar (M3) is one of the most common procedures in daily dental practice. This procedure accounts for 95% of teeth removed in patients between 19 and 21 years of age in the United States¹. Surgeons advocate the surgery for various reasons such as prophylaxis, orthodontics, and treatment of pathology associated with impacted teeth². Some researchers have advised early treatment to avoid postoperative complications.

The advisability and timing of surgical removal of asymptomatic M3s is uncertain among dental practitioners³. Early removal almost always involves developing tooth germs, so the term ‘germectomy’ was introduced. The role of the oral surgeon is to select the appropriate time to remove the M3 germ, affording fewer treatment sequelae and good outcomes³.

Third molar crypt formation begins at 3 to 4 years of age. Calcification starts at 7 to 10 years of age and is complete by 12 to 16 years of age. Eruption of the M3 begins between 17 and 21 years of age⁴. Studies have defined germectomy in various terms^5-13.(Table 1) One study described germectomy as the removal of M3s in patients between 9 and 16 years of age⁵. In contrast, the degree of root formation was defined in several other studies^6-14. Some authors defined germectomy as surgical removal of M3s in patients with formation of only the tooth crown¹⁴. Several others have described the surgery as removal of the developing bud prior to anchoring of the roots in the jaw¹¹. A white paper by the American Association of Oral and Maxillofacial Surgeons regarding M3 data described germectomy as the removal of a tooth that has one-third (or less) root development with a radiographically discernible periodontal ligament⁷. This definition was adopted by Sivolella et al.⁸ in 2011. Most authors defined the tooth in the procedure as having one-third or less of its root^6,10. Recently, a systematic review advocated Demirjian’s classification of types B, C, and D for the definition of germectomy^13,15,16.(Fig. 1)

In summary, two distinct criteria are used to determine germectomy—the chronological age of patients and the anatomical appearance and stage of root formation. These definitions can be used interchangeably as differences in treatment are not clinically significant.

Opinions differ regarding the indications for germectomy. Some surgeons favor early surgical removal for various reasons. First, early surgical removal would obviate any related risks such as dental caries, pulpitis, pericoronitis, or cystic lesions^6,9,17,18. Second, early removal could reduce postoperative complications compared to delayed surgical removal. Less frequent alveolar osteitis and nerve injury are observed in patients with removed M3 for both the inferior alveolar nerve and lingual nerve^6,19 as the alveolar bone of teenagers is more flexible. Several authors have stated the simplicity of the procedure and reported a decreased operation time compared to conventional surgical removal at a later age⁹. Moreover, younger patients tend to have fewer systemic conditions than older patients¹⁹. Accordingly, the morbidity associated with early germectomy seems to be less serious than with delaying removal to an older age. Third, orthodontic advantages have been discussed including prevention of crowding from M3 eruption and creation of space without the need for premolar extraction^6,17.

Anterior crowding represents a longstanding controversy regarding the presence of M3s. In a recent systematic review and in other literature, the issue is debated^13,20,21. Mandibular second molar (M2) impaction is another reported indication. One study determined impacted M3s to be associated with impacted M2s, while another study found that M3 germectomy did not benefit the M2 uprighting process. Meanwhile, the authors of the systematic review supported the idea of M3 germectomy in cases of impacted M2 since delaying M3 removal would only put the M2 at greater risk of dental caries or periodontitis and/or complicate M2 eruption¹³. Furthermore, germectomy of M3s was justified to gain space in cases requiring molar distalization. For these reasons, some orthodontists consider early surgical removal of M3 to reduce unstable dental arch alignment.

A prior systematic review evaluated the indications for M3 removal in syndromic or incompliant patients. They suggested early removal in cases of morphologic abnormalities, such as Ekman-Westborg-Julin syndrome associated with macrodontic multituberculate impacted M3, self-mutilating behavior, and/or recurrent epilepsy that can be triggered by pain from impacted M3²².

In contrast to mandibular M3, germectomy of maxillary M3 is more difficult and time-consuming because of the higher tooth bud position¹⁷. Several authors have reported surgical removal of maxillary M3 in young patients with displacement of the tooth bud into the infratemporal fossa^23-26. One author stated that M3 removal presents operative challenges, and germectomy should be limited to mandibular tooth buds²⁷. Most maxillary distalization caused superior and posterior movements of unerupted M3. The results suggest that distalization in adolescents with unerupted M3s may be achieved without early germectomy²⁸. A systematic review revealed that the effect of the maxillary M2 and M3 eruption stage on maxillary molar distalization was nominal²⁹, creating more risk than benefit for germectomy of maxillary M3.

Some authors did not support the idea of germectomy, while others argued that early extraction was beneficial, even though it did not have to be as early as germectomy. There were no significant differences in complications among patients 12-18 years of age³⁰. Formation of two-thirds of the tooth roots formed is a preferred time for germectomy to avoid morbidities associated with eruption of M3 and an easier procedure because some portion of the tooth would have emerged out of the bony crypt. Several studies found that postoperative complications increase only in patients older than 23-24 years^5,19.

Another reason why surgeons do not strongly support germectomy is that the orthodontic advantages are not definitive. The relationship between anterior crowding and M3s has not been established. A randomized, controlled trial in 1998 found that removal of M3 cannot be justified to reduce or prevent late incisor crowding³¹. Cassetta and Altieri³² found that germectomy of M3 did not simplify uprighting of impacted M2, calling into question the orthodontic purposes for early removal of M3. Furthermore, early germectomy of developing tooth buds could deprive M3s of the potential as future tooth reservoirs for autotransplantation, especially in syndromic patients prone to multiple tooth loss^17,22.

With so many contradicting opinions, some authors have proposed a middle ground of appropriate age to determine the fate of M3s. Chiapasco et al.⁵ proposed waiting until 17-24 years of age, while Haddad¹⁰ offered a narrower range of 18-20 years of age. Taken together, the optimal age range for M3 evaluation without increasing the accompanying risks of M3 eruption and postoperative complications was between 18-20 years of age^5,10.

The best chronological age for germectomy has yet to be determined. Seven to ten years of age has proven to be a difficult time for surgery due to poor patient compliance and reluctant parental consent. Moreover, the prognosis of M2 is difficult to evaluate in this age range because of the lack of certain criteria for space discrepancy evaluations³³.

The surgical removal of M3s when M2s have yet to erupt can be difficult. Some clinicians do not recommend this surgery for patients between 11-12 years of age because of their uncooperativeness during surgery. Moreover, flap designs and suturing can be complicated³³.

Patients between 13 and 14 years of age appear to be the best candidates for germectomy, as the M2 is fully erupted, patient compliance is satisfactory, and the dental volume is sufficient to allow minimally invasive surgery³³.

Details of the germectomy procedure regarding anesthetic technique, preoperative preparation, flap designs, ostectomy, and odontectomy have been described in several reports.

Oral surgeries are often accompanied by postoperative complications, and germectomy is no exception. General non-specific postoperative complications such as pain, swelling, and trismus were recorded in the literature^6,17. Most complications were associated with decreased available space at the ramus posterior to M3 or with Nolla’s third molar calcification less than stage 7 or 1/3 completed root form³⁸.

Nerve paresthesia was one of the main focuses in the literature on germectomy. During the early stages of tooth development, roots are shorter and often further from the inferior alveolar canal. Consequently, nerve paresthesia was believed to be less of an issue in germectomy compared to delayed surgical removal and was not observed in all cases of germectomy⁵. The lingual nerve was also studied, and no evidence of paresthesia was found after germectomy^8,11,30.

Dry socket or alveolar osteitis is another complication frequently reported after removal of M3. In adult patients, the incidence of dry socket is around 4.6%³⁹. Although Bjørnland et al.¹⁷ observed dry socket in 1.8% of cases, while Chiapasco et al.⁵ reported no dry socket in the germectomy group compared to 0.5%-2.1% in other groups.

Delayed-onset infection (DOI) was defined as swelling and/or purulent drainage from the alveolus 15 days to 2 months postoperatively³⁴. Another study defined DOI as an inflammatory swelling of the operated area any time after the removal of sutures at 1 week postoperatively⁴⁰. Antibiotic prophylaxis of 2 g of amoxicillin 1 hour prior to germectomy can reduce DOI significantly¹⁴. A lower Ganss ratio was associated with increasing DOI. The Ganss ratio is the comparison between the distal surface of the M2 to the anterior border of the ramus and mesiodistal width of the M3^34,41.(Fig. 4) Other risks for infection include full soft tissue coverage, complete bony impaction, Pell and Gregory’s class III, deeper position, younger age, and lower Nolla stage⁴⁰.

Germectomy is a procedure to remove M3 germs that have either formed only a crown or the crown and no more than one-third of the root length. Surgeons have various opinions on whether germectomy should be performed. It is important to understand the benefits and drawbacks of each treatment plan before developing one for each M3. Communication with patients and their parents about the plan and its outcome must be prioritized. Many surgeons have proposed distinct surgical techniques. It is essential to fully evaluate each aspect of the treatment plan and surgical techniques to be used. Finally, early M3 removal can reduce and eliminate some of the most unpleasant complications of late M3 removal. However, other complications could occur more frequently and patients must be well informed.