Removal of mandibular third molars: An overview of risks, a proposal for international community and guidance.

The aim of this proposal is to (1) review the current literature, (2) shed light on the importance of creating universally accepted guidelines, (3) provide help and guidance in the decision-making process with regard to the removal of mandibular third molars (M3Ms), and (4) reduce the risk of exposing the patient to unnecessary harm and complications due to the inappropriate removal or retention of M3Ms.It is obvious that the indications for the extraction of M3Ms will continue to be an area of controversy and strong debate. The evidence for or against prophylactic extraction is ambivalent; there is evidence to accept or reject the stance against prophylactic extraction in some specific cases, and there are published articles to support both opposing views. The available guidelines on the extraction of third molars are limited in number, and are mostly tailored to fit specific settings or countries. There are no available guidelines that might be widely used to help in the decision-making process for the international community. We hope this proposal will constitute an important first step toward creating universally accepted guidance.

Prophylactic removal of impacted mandibular third molars: a systematic review and economic evaluation.

BACKGROUND: Impacted third molars are third molars that are blocked, by soft tissue or bone, from fully erupting through the gum. This can cause pain and disease. The treatment options for people with impacted third molars are removal or retention with standard care. If there are pathological changes, the current National Institute for Health and Care Excellence guidance states that the impacted third molar should be removed. OBJECTIVE: The objective of this study was to appraise the clinical effectiveness and cost-effectiveness of the prophylactic removal of impacted mandibular third molars compared with retention of, and standard care for, impacted third molars. METHODS: Five electronic databases were searched (1999 to 29 April 2016) to identify relevant evidence [The Cochrane Library (searched 4 April 2016 and 29 April 2016), MEDLINE (searched 4 April 2016 and 29 April 2016), EMBASE (searched 4 April 2016 and 29 April 2016), EconLit (searched 4 April 2016 and 29 April 2016) and NHS Economic Evaluation Database (searched 4 April 2016)]. Studies that compared the prophylactic removal of impacted mandibular third molars with retention and standard care or studies that assessed the outcomes from either approach were included. The clinical outcomes considered were pathology associated with retention, post-operative complications following extraction and adverse effects of treatment. Cost-effectiveness outcomes included UK costs and health-related quality-of-life measures. In addition, the assessment group constructed a de novo economic model to compare the cost-effectiveness of a prophylactic removal strategy with that of retention and standard care. RESULTS: The clinical review identified four cohort studies and nine systematic reviews. In the two studies that reported on surgical complications, no serious complications were reported. Pathological changes due to retention of asymptomatic impacted mandibular third molars were reported by three studies. In these studies, the extraction rate for retained impacted mandibular third molars varied from 5.5% to 31.4%; this variation can be explained by the differing follow-up periods (i.e. 1 and 5 years). The findings from this review are consistent with the findings from previous systematic reviews. Two published cost-effectiveness studies were identified. The authors of both studies concluded that, to their knowledge, there is currently no economic evidence to support the prophylactic removal of impacted mandibular third molars. The results generated by the assessment group's lifetime economic model indicated that the incremental cost-effectiveness ratio per quality-adjusted life-year gained for the comparison of a prophylactic removal strategy with a retention and standard care strategy is £11,741 for people aged 20 years with asymptomatic impacted mandibular third molars. The incremental cost per person associated with prophylactic extraction is £55.71, with an incremental quality-adjusted life-year gain of 0.005 per person. The base-case incremental cost-effectiveness ratio per quality-adjusted life-year gained was found to be robust when a range of sensitivity and scenario analyses were carried out. LIMITATIONS: Limitations of the study included that no head-to-head trials comparing the effectiveness of prophylactic removal of impacted mandibular third molars with retention and standard care were identified with the assessment group model that was built on observational data. Utility data on impacted mandibular third molars and their symptoms are lacking. CONCLUSIONS: The evidence comparing the prophylactic removal of impacted mandibular third molars with retention and standard care is very limited. However, the results from an exploratory assessment group model, which uses available evidence on symptom development and extraction rates of retained impacted mandibular third molars, suggest that prophylactic removal may be the more cost-effective strategy. FUTURE WORK: Effectiveness evidence is lacking. Head-to-head trials comparing the prophylactic removal of trouble-free impacted mandibular third molars with retention and watchful waiting are required. If this is not possible, routine clinical data, using common definitions and outcome reporting methods, should be collected. STUDY REGISTRATION: This study is registered as PROSPERO CRD42016037776. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 30. See the NIHR Journals Library website for further project information.

Third molars, commonly known as wisdom teeth, may come through the gum (erupt) without any problems, usually during young adulthood (aged 18­24 years). However, in some cases they are unable to erupt because they are poorly aligned or obstructed by other teeth, gums or bone. They are then referred to as 'impacted'. Historically, dentists often recommended that these teeth be removed, so as not to cause problems later in life. This is referred to as 'prophylactic' removal. In 2000, the National Institute for Health and Care Excellence reviewed this practice and recommended that these teeth should not be removed if they are not bothersome to the person. Many dentists and oral surgeons have disagreed with this decision, believing that it is more difficult to remove these teeth later in life, and that there are more complications for the patient if they are removed later in life. Our review group carried out a systematic review of the available clinical effectiveness and cost-effectiveness evidence of the prophylactic removal of impacted third molars. The review identified four clinical studies, none of which provided strong evidence for or against the prophylactic removal of these teeth. These findings are similar to those of nine previous reviews. There is also very little research reported that relates to the cost-effectiveness of the procedure, with only three studies identified. With the available evidence on the rates of extraction and the symptoms experienced by people who keep their impacted mandibular third molar, we built an exploratory economic model to assess the cost-effectiveness of recommending prophylactic removal compared with that of recommending watchful waiting. Results from the model suggested that a prophylactic removal strategy costs more than a watchful waiting strategy, but leads to improvements in quality of life. When the costs and quality-of-life measures that are associated with the two strategies are compared, the resulting statistic is £11,741 per quality-adjusted life-year gained, which would probably be good value for money for the NHS.

Prophylactic Extraction of Third Molars: Evidence-Based Dentistry

his new perspective article was performed to investigate the evidence from published dental literature about the prophylactic extraction of asymptomatic (or disease-free) impacted third molars (ITM) in adolescents and young adults. This clinical procedure is common until today and has been the origin of controversy among the dental community worldwide. However, evidence-based data from wellconducted clinical studies and systematic reviews are not sufficient to justify the routine prophylactic extraction of ITM. Active surveillance at regular intervals has been proposed as a better management strategy. As a conclusion, surgical removal of ITM is only justified in the presence of specific pathosis, independently of the patient's age.

l presente artículo se realizó para investigar la evidencia en literatura dental publicada sobre la extracción profiláctica de terceros molares impactados asintomáticos (o libres de enfermedad) (TMI) en adolescentes y adultos jóvenes. Este procedimiento clínico es común y ha sido el origen de la controversia entre la comunidad dental en todo el mundo. Sin embargo, los datos basados en evidencia de estudios clínicos y revisiones sistemáticas no son suficientes para justificar la extracción profiláctica rutinaria de TMI. La vigilancia activa a intervalos regulares se ha propuesto como una mejor estrategia de manejo. Como conclusión, la remoción quirúrgica de TMI sólo se justifica en presencia de patología específica, independientemente de la edad del paciente.

Incidence of distal caries in mandibular second molars due to impacted third molars: Nonintervention strategy of asymptomatic third molars causes harm? A retrospective study.

BACKGROUND: Removal of impacted third molars is the most common oral surgical procedure. Many investigators have questioned the necessity of removal in patients who are free of symptoms or associated pathologies. AIM: The aim of this retrospective study was to evaluate the incidence of caries on distal aspect of mandibular second molars in patients referred for corresponding third molar assessment and to identify its association with angular position and depth of the impacted mandibular third molars based on the classification of Pell and Gregory. METHODOLOGY: Records of 150 patients with impacted third molar presenting to the Department of Oral and Maxillofacial Surgery, Sri Rajiv Gandhi College of Dental Sciences and Hospital, were assessed retrospectively. The radiographic angulation and depth of mandibular third molar impaction were determined and compared to determine the relationship with incidence of caries on the distal surface of the second molar. RESULTS: According to this study results, 37.5% cases show caries on the distal aspect of mandibular second molars. The incidence of caries with mesioangular impacted third molars was 55%. A majority of these mesioangular cases were Level B and Class I as per the Pell and Gregory classification. CONCLUSION: The prophylactic extraction of mandibular third molars is indicated if the angulation is between 30° and 70° and is justified by incidence of distal caries in the second molars.

Retrospective analysis of the prevalence and incidence of caries in the distal surface of mandibular second molars in British military personnel.

Mandibular third molars are commonly removed because of distal caries in the adjacent tooth. To find out the prevalence of distal caries in mandibular second molars we retrospectively studied the primary care dental records of 720 British military personnel (653 men and 67 women) from various centres. These records are standardised and personnel are required to attend for inspection regularly. Those who had been under 20 years of age at enlistment, who had served for at least five years, and had five recorded dental inspections, were included. The median (IQR) period from the first to last inspection was 15 (9.7 - 19.2) years, and inspections were a median (IQR) of 14.1 (12.8 - 15.8) months apart. A total of 59/1414 (4.2%) mandibular second molars developed caries in their distal surfaces. This was 4% higher when they were associated with a partially-erupted mandibular third molar than when associated with one that was fully erupted or absent (29/414 (7%) compared with 30/1000 (3%); p=0.001). Carious lesions developed in the distal aspect of 22/133 mandibular second molars (16.5%) that were adjacent to a mesioangularly impacted third molar. Of these, 19/22 were successfully restored. Four mesioangularly impacted mandibular third molars would have to be extracted to prevent one case of distal caries in a second molar (number needed to treat=3.25). Second molars that are associated with a partially-erupted mesioangular mandibular third molar have a higher risk of caries, and this can be reduced by removal of the third molar. However, distal caries in second molars seems to be a treatable and slowly-developing phenomenon and we recommend that the merits and risks of the prophylactic removal of third molars should be discussed with the patient, who should have long-term clinical and radiographic checks if the tooth is retained.

Clinical and pathologic features related to the impacted third molars in patients of different ages: A retrospective study in the Korean population.

BACKGROUND/PURPOSE: The surgical extraction of impacted third molars (ITMs) is a common surgical procedure in dentistry. If prophylactic removal of ITMs is beneficial, however, is a still disputed issue. The aim of this study was to analysis the pathologic changes in impacted third molars (ITMs) and adjacent teeth according to patient age groups in the Korean population to determine if the prophylactic removal of ITMs is to be supported or not. MATERIALS AND METHODS: A retrospective study of patients who underwent surgical extraction of impacted third molars was performed. The patients were divided into 5 groups according to their age. Each group was analyzed with respect to patients' chief complaints, specific pathologic conditions in ITMs, and the damage to adjacent teeth due to untreated ITMs. RESULTS: In this study, 2883 impacted third molars in 1109 patients were analyzed. The most common patients' chief complaint was pain, and the frequency of pain was significantly higher in older age groups. The frequency and severity of pathologic changes in ITMs and adjacent second molars due to ITMs were increased with advancing age. CONCLUSION: Based on the results of this study, we conclude that the prophylactic removal of ITMs that have a higher probability of pathologic changes can be considered to be a reasonable treatment modality in younger patients to reduce morbidity resulting from surgical extraction compared with patients who attained advanced age.