Do wisdom teeth always need to be removed? Can two be removed in one visit?｜證據鏈

Do wisdom teeth always need to be removed? Can two be removed in one visit?｜證據鏈

F-Units (fact ledger)

• F1｜Internal selection record: 14 clinic-site GSC reconciliation; 19,331 impressions for the query at one site, with a mounting list of 1 clinic. Internal data only, not medical evidence.｜source #18｜confidence=high｜basis=internal_dataset｜period=GSC retention window (from 2025-03-22)｜geo: TW

• F2｜Editorial framework for the three routes, risk comparison, denominator labelling, scheduling question, and division of labour; not a diagnostic tool.｜source #20｜confidence=n/a｜basis=editorial_framework｜period=2026-08-06｜geo: universal

• F3｜Cochrane review: insufficient evidence to determine removal versus retention of asymptomatic disease-free impacted wisdom teeth; shared decision-making and regular clinical assessment if retaining; possible adjacent-second-molar periodontitis is very-low-certainty evidence.｜source #1｜confidence=verified｜basis=peer_reviewed (PMID 32368796)｜period=2020 (searched to 2019-05-10); version-chain and retraction check on 2026-08-06: `CD003879` returned 4 records (15846686/22696337/27578151/32368796); pub5 current, all pubtypes had no Retracted Publication and no title WITHDRAWN｜geo: universal｜span: 「Insufficient evidence is available to determine whether asymptomatic disease-free impacted wisdom teeth should be removed or retained」「Although retention of asymptomatic disease-free impacted wisdom teeth may be associated with increased risk of periodontitis affecting adjacent second molars in the long term, the evidence is very low certainty」「Given the current lack of available evidence, patient values should be considered and clinical expertise used to guide shared decision-making with people who have asymptomatic disease-free impacted wisdom teeth」「If the decision is made to retain these teeth, clinical assessment at regular intervals to prevent undesirable outcomes is advisable」

• F4｜Review background: possible pericoronitis, root resorption, periodontal disease, caries, cysts and tumours; older surgical removal associated with more postoperative complications, pain and discomfort. Background, not comparative results.｜source #2｜confidence=verified｜basis=peer_reviewed (PMID 32368796)｜period=2020｜geo: universal｜span: 「Impacted wisdom teeth may be associated with pathological changes, such as pericoronitis, root resorption, gum and alveolar bone disease (periodontitis), caries and the development of cysts and tumours」「When surgical removal is performed in older people, the risk of postoperative complications, pain and discomfort is increased」

• F5｜Same review: UK hospital RCT and US prospective cohort; subgroup 416 healthy men aged 24-84 followed 3 to over 25 years; RCT 164 randomised/77 analysed adolescents, high risk of bias and no clinically significant 5-year arch effect; no eligible quality-of-life study.｜source #3｜confidence=verified｜basis=peer_reviewed (PMID 32368796)｜period=2020｜geo: universal｜span: 「This review update includes the same two studies that were identified in our previous version of the review: one RCT with a parallel-group design, which was conducted in a dental hospital setting in the United Kingdom, and one prospective cohort study, which was conducted in the private sector in the USA」「One prospective cohort study, reporting data from a subgroup of 416 healthy male participants, aged 24 to 84 years」「during a follow-up period of three to over 25 years」「there is insufficient evidence to demonstrate a difference in caries risk associated with the presence or absence of impacted wisdom teeth」「One RCT with 164 randomised and 77 analysed adolescent participants compared the effect of extraction with retention of asymptomatic disease-free impacted wisdom teeth on dimensional changes in the dental arch after five years」「No evidence from this study, which was at high risk of bias, was found to suggest that removal of asymptomatic disease-free impacted wisdom teeth has a clinically significant effect on dimensional changes in the dental arch」「No eligible studies in this review reported the effects of removal compared with retention of asymptomatic disease-free impacted wisdom teeth on health-related quality of life」

• F6｜UK assessment: 4 cohorts and 9 systematic reviews; pathological change then indicated removal in NICE guidance; later extraction of retained teeth 5.5%-31.4%, explained by 1- and 5-year follow-up; comparative evidence very limited and exploratory UK-cost model had no head-to-head trial. UK-system context only.｜source #4｜confidence=verified｜basis=peer_reviewed (PMID 32589125)｜period=2020 (searched to 2016-04-29)｜geo: universal｜span: 「If there are pathological changes, the current National Institute for Health and Care Excellence guidance states that the impacted third molar should be removed」「The clinical review identified four cohort studies and nine systematic reviews」「Pathological changes due to retention of asymptomatic impacted mandibular third molars were reported by three studies」「In the two studies that reported on surgical complications, no serious complications were reported」「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 evidence comparing the prophylactic removal of impacted mandibular third molars with retention and standard care is very limited」「suggest that prophylactic removal may be the more cost-effective strategy」

• F7｜Meta-analysis of 13 studies/13,788 patients: distal caries prevalence 29.89% (95% CI 21.05%-38.74%), mesioangular 43.37% (95% CI 33.03%-53.70%). No unimpacted control; not individual probability or extraction effect.｜source #5｜confidence=verified｜basis=peer_reviewed (PMID 39853442)｜period=2025 (past-decade studies); search date 2026-08-06｜geo: universal｜span: 「Thirteen studies met the inclusion criteria and underwent analysis; they included a total of 13,788 patients」「The overall prevalence of caries in MSMs adjacent to IMTMs was 29.89% (CI 95%: 21.05 - 38.74%; p < 0.001)」「Following Winter's classification, the mesioangular position was the most frequently associated with caries with 43.37% (CI 95%: 33.03 - 53.70%; p < 0.001)」

• F8｜Meta-analysis of normal-radiographic (≤3 mm), asymptomatic pericoronal follicles: 7 studies/592 follicles; cystic change 26.7% (95% CI 3.7% to 49.6%) and dentigerous cyst 21.6% (95% CI 12.9% to 32.2%), both I2 >97%; evidence does not support prophylactic extraction solely from these findings.｜source #6｜confidence=verified｜basis=peer_reviewed (PMID 42144023)｜period=2026; search date 2026-08-06; esummary pubtype no Retracted Publication｜geo: universal｜span: 「in pericoronal follicles with a normal radiographic appearance (≤3 mm) associated with asymptomatic impacted third molars」「Seven studies (592 pericoronal follicles) were included」「The pooled prevalences of cystic changes and dentigerous cysts were respectively 26.7%, (95% CI: 3.7 to 49.6%) and 21.6% (95% CI: 12.9 to 32.2%), both with very high heterogeneity (I2 > 97%)」「current evidence does not support prophylactic extraction based solely on these findings」

• F9｜Histopathology review: 16 of 1,300 studies; extracted impacted teeth had cyst/tumour prevalence 5.3%, cysts 4.4% (95% CI 2.5% to 6.8%), tumours 0.5% (95% CI 0.2% to 0.9%). Extraction denominator has selection bias; not population incidence.｜source #7｜confidence=verified｜basis=peer_reviewed (PMID 31005378)｜period=2019; version recency check on 2026-08-06 found this review and narrower 2026 F8｜geo: universal｜span: 「From 1,300 studies identified, 16 met the inclusion criteria」「The prevalence of odontogenic cysts and tumors associated with ITM was 5.3% (95%CI: 3.1%-8.1%) of ITM」「Odontogenic cysts in particular were found in 4.4% (95%CI: 2.5-6.8%) of the extracted ITM, whilst odontogenic tumors in 0.5% (95%CI: 0.2-0.9%)」

• F10｜Retrospective observation: 51 patients, mean age 45, 68 second molars, 20-month mean interval; no significant bone-level change and no support for substantial prophylactic-extraction bone benefit. Small, single-centre, short-term.｜source #8｜confidence=verified｜basis=peer_reviewed (PMID 40647642)｜period=2025; search date 2026-08-06｜geo: universal｜span: 「A total of 51 patients met the inclusion criteria, with a mean age of 45 years (SD ± 13)」「Sixty-eight second molars were assessed at baseline (T0) and follow-up (T1), with a mean interval of 20 months (SEM ± 62 days). No significant changes were found in vertical, oblique, or angular bone levels between T0 and T1」「this analysis does not provide evidence to support the hypothesis that prophylactic extraction of ITMs yields significant bone-sparing benefits」

• F11｜Pericoronitis review: local treatment preferred; antibiotics reserved for severe conditions; almost 75% of dentists in questionnaires and over half of patient-data cases received antibiotics. Not a judgment on any clinician.｜source #9｜confidence=verified｜basis=peer_reviewed (PMID 34202699)｜period=2021｜geo: universal｜span: 「recommending the local therapy over antibiotic prescribing, which should be reserved for severe conditions」「Questionnaires among dentists revealed that almost 75% of them prescribed antibiotics for pericoronitis」「Studies involving patients showed that antibiotics were prescribed to more than half of the patients with pericoronitis」

• F12｜Cochrane review: 62 trials/4643 participants; background indications include pain, swelling, trismus and infection-spread prevention. Short-term pain, swelling and trismus common; infection, dry socket and trigeminal injury less common.｜source #10｜confidence=verified｜basis=peer_reviewed (PMID 32712962)｜period=2020 (searched to 2019-07-08); version-chain check on 2026-08-06: `CD004345` returned 2 records (25069437/32712962), pub3 current, pubtype no Retracted Publication｜geo: universal｜span: 「The indications for surgical removal of these teeth are alleviation of local pain, swelling and trismus, and also the prevention of spread of infection that may occasionally threaten life」「Surgery is commonly associated with short-term postoperative pain, swelling and trismus. Less frequently, infection, dry socket (alveolar osteitis) and trigeminal nerve injuries may occur」「We included 62 trials with 4643 participants」

• F13｜Review of 23 studies/26,427 patients/44,171 teeth: transient IAN deficit 1.20%, permanent 0.28%; depth, canal contact, technique, nerve exposure and surgeon experience statistically significant. Pooled setting data, not individual prediction.｜source #11｜confidence=verified｜basis=peer_reviewed (PMID 31476533)｜period=2020; recency search on 2026-08-06 returned 12, with F14 a newer imaging-predictor review of a different question｜geo: universal｜span: 「Twenty-three studies out of 693 articles from the initial search were finally included, which summed up a total of 26,427 patients (44,171 teeth)」「Among 44,171 IMTM extractions performed by various grades of operators, 1.20% developed transient IAN deficit and 0.28% developed permanent IAN deficit respectively」「Depth of impaction (P<0.001), contact between mandibular canal (MC) and IMTM (P<0.001), surgical technique (P<0.001), intra-operative nerve exposure (P<0.001), and surgeon's experience (P<0.001) were statistically significant as contributing risk factors of IAN deficits」

• F14｜Imaging-predictor meta-analysis: 18 studies, 8 features, 16 low risk of bias, moderate-to-high GRADE; OR 9.87 cortical-bone absence, 8.25 dumbbell canal, 3.82 lingual position, 5.06 all three. Relative rather than absolute risk.｜source #12｜confidence=verified｜basis=peer_reviewed (PMID 41770179)｜period=2026; search date 2026-08-06; esummary pubtype no Retracted Publication｜geo: universal｜span: 「In 18 studies, researchers identified 8 tomographic features that predict IAN injury during third-molar extraction. Sixteen studies had a low risk of bias」「The Grading of Recommendations Assessment, Development and Evaluation framework indicated moderate to high certainty of evidence」「Significant increases in odds ratios (ORs) (with P < .001) were observed for the absence of cortical bone (OR, 9.87; 95% CI, 4.10 to 23.83), a dumbbell-shaped canal (OR, 8.25; 95% CI, 3.19 to 21.35), and a lingual position (OR, 3.82; 95% CI, 1.95 to 7.39」「Patients exhibiting all 3 features had an increased risk of experiencing IAN injury after mandibular third-molar extraction (OR, 5.06; 95% CI, 2.23 to 11.39)」

• F15｜Coronectomy meta-analysis for teeth contacting the mandibular canal: paresthesia RR 0.09; no significant infection or dry-socket reduction; certainty very low to moderate; RoB 2.0 assessed bias and the pain analysis included 1,037 intervention events and 1,054 control events. Roots remain and follow-up/further management may be needed.｜source #13｜confidence=verified｜basis=peer_reviewed (PMID 40562625)｜period=2025; search date 2026-08-06｜geo: universal｜span: 「A significant reduction in the relative risk of paresthesia was observed (0.09 [95% CI: 0.03, 0.25], P < .001) with low heterogeneity (I² = 0%)」「there was no significant reduction in the risk of infection (P = .370, I² = 56%) or dry socket (P = .230, I² = 27%)」「the heterogeneity (I² = 0%-56%) and sample sizes reduced the certainty of the GRADE evidence from very low to moderate」

• F16｜Quality-of-life meta-analysis: 1,141 records, 13 studies, 6 meta-analysed; local anaesthesia only; day-1 OHIP-14 17.57 higher (95% CI 11.84-23.30; I2 96%), decreasing later. Not an individual pain forecast.｜source #14｜confidence=verified｜basis=peer_reviewed (PMID 29797177)｜period=2018 (searched to 2017-03); a 2019:2026 search on 2026-08-06 returned 14 and found no updated review of the same question｜geo: universal｜span: 「besides procedures performed under local anesthesia」「A total of 1141 studies were identified. Of this total, 13 articles were selected in the present systematic review, of which six studies were included in the meta-analysis」「The OHIP-14 mean score on the first postoperative day was 17.57 (95% CI 11.84-23.30, I2 = 96%) higher than the preoperative period」「This systematic review revealed that the highest negative impact on quality of life of individuals submitted to third molar surgery was observed on the first postoperative day, decreasing over the follow-up period」

• F17｜Indonesian single-centre retrospective study: 916 people, 59% women, 60.9% aged 21-30, 77% advanced difficulty; difficulty linked to day-1 pain/trismus/paresthesia and age to week-1 pain/swelling/trismus; ≥51 and high complexity flagged. Cannot prove causation.｜source #15｜confidence=verified｜basis=peer_reviewed (PMID 35027927)｜period=2022; search date 2026-08-06｜geo: universal｜span: 「Among 916 respondents, the majority of the sample was females (59%) and the dominant age group (60.9%) was the age group of 21-30 years while the dominant surgical difficulty level was shown by the advanced cases group (77%)」「there was a significant correlation between surgical difficulty level and postoperative complications including pain, trismus, and paresthesia on the first-day assessment. On the other hand, age was significantly related to complications like pain, swelling, and trismus on the first-week assessment」「Dentists should take into consideration that older patients (≥51 years) and patients with complex surgical level are more vulnerable to severe postoperative complications」

• F18｜German single-centre retrospective analysis: 200 patients/554 teeth, 2023-07 to 2024-07, 30-year cut-off; no significant age-group differences in IAN/LN hypesthesia, bleeding or infection. Not proof of no difference and no difficulty-complication analysis.｜source #16｜confidence=verified｜basis=peer_reviewed (PMID 39375233)｜period=2024; search date 2026-08-06｜geo: universal｜span: 「The clinical findings, digital panoramic radiographs and perioperative data of 200 patients (554 impacted third molars) that had been subjected to tooth extraction, from July 2023 until July 2024, were analyzed」「IAN hypesthesia, LN hypesthesia, postoperative bleeding and postoperative infection did not show any significant differences regarding patients' age」「The current findings suggest that age (cut-off 30 years) does not statistically correlate with a higher risk for postoperative complications in impacted third molar surgery in contrast to recent publications」

• F19｜Cochrane antibiotic review: 23 trials, about 3,206 randomised/2,583 analysed, 16 high risk of bias; may reduce postoperative infectious complications by about 66% (RR 0.34, 95% CI 0.19-0.64, low certainty); NNT 19 (95% CI 15-34). No immunocompromised extraction study; individual clinical assessment required.｜source #17｜confidence=verified｜basis=peer_reviewed (PMID 33624847)｜period=2021 (searched to 2020-04-16); `CD003811` check on 2026-08-06 returned 2 records (23152221/33624847), current version, pubtype no Retracted Publication｜geo: universal｜span: 「We included 23 trials that randomised approximately 3206 participants (2583 analysed) to prophylactic antibiotics or placebo」「which means that 19 people (95% CI 15 to 34) need to be treated with antibiotics to prevent one infection following extraction of impacted wisdom teeth」「None of the studies evaluated tooth extraction in immunocompromised patients」「clinicians should evaluate if and when to prescribe prophylactic antibiotic therapy before a dental extraction for each patient on the basis of the patient's clinical conditions」

• F20｜Cochrane review: local operative removal of inflammation/infection source is first line; systemic antibiotics only for spreading infection or systemic involvement. Apical-infection source, used only for clinician-level red-flag concepts.｜source #18｜confidence=verified｜basis=peer_reviewed (PMID 38712714)｜period=2024 (searched to 2022-11); `CD010136` chain check returned 3 records, pub4 current, pubtype no Retracted Publication｜geo: universal｜span: 「Clinical guidelines recommend that the first-line treatment for these conditions should be removal of the source of inflammation or infection by local operative measures, and that systemic antibiotics are currently only recommended for situations where there is evidence of spreading infection (cellulitis, lymph node involvement, diffuse swelling) or systemic involvement (fever, malaise)」

• F21｜Deep-neck-infection textbook: neck swelling, dysphagia, dysphonia, trismus, fever, neck pain and respiratory distress; immune compromise, comorbidity, trauma, instrumentation and intravenous drug use influence spread/severity. Not dental-only and no rate/prognosis claim.｜source #19｜confidence=verified｜basis=textbook (PMID 30020634)｜period=entry version 2026-01; search date 2026-08-06｜geo: universal｜span: 「Symptoms often result from local pressure effects on the respiratory, nervous, or gastrointestinal tracts, including neck swelling, dysphagia, dysphonia, and trismus」「often involving fever, neck pain, and respiratory distress」「host factors such as immunocompromised states, comorbid conditions, trauma, recent instrumentation, and intravenous drug use can influence the spread and severity of infections」

• F22｜Taiwan Medical Care Act Article 87(2): medical knowledge/research, patient health education and academic publications not intended to solicit medical business are not medical advertising. Taiwan publication positioning, not medical evidence.｜source #20｜confidence=verified｜basis=law｜period=current text; 2026-08-05 HTTP 200 and verbatim match｜geo: TW

• F23｜Editorial evidence-gap statement: five listed PubMed E-utilities scheduling searches on 2026-08-06 returned 0, 0, 0, 0 and 1 records; the one was PMID 27656565, coronectomy outcome rather than scheduling. No direct comparison, and no tooth-count, side, anaesthesia or “double discomfort” recommendation.｜source #20｜confidence=n/a｜basis=editorial_framework (PMID 27656565)｜period=2026-08-06｜geo: universal

Sources

Retrieved on 2026-08-06; PubMed abstracts were obtained through E-utilities efetch and checked verbatim. No verbatim quotation in this card comes from paywalled full text.

1. Ghaeminia H, Nienhuijs ME, Toedtling V, et al. Surgical removal versus retention for the management of asymptomatic disease-free impacted wisdom teeth. Cochrane Database Syst Rev. 2020;5(5):CD003879. PMID 32368796
2. Hounsome J, Pilkington G, Mahon J, et al. Prophylactic removal of impacted mandibular third molars: a systematic review and economic evaluation. Health Technol Assess. 2020;24(30):1-116. PMID 32589125
3. Revuelta-Cortés P, Cortés-Bretón Brinkmann J, Argandoña-Flores M, et al. Prevalence of distal caries in second molar associated with impacted mandibular third molar and the position and level of impaction: a systematic review and meta-analysis. Clin Oral Investig. 2025;29(1):83. PMID 39853442
4. de Andrade Tutu JS, de Sousa Lopes Cascaes P, Peralta-Mamani M, et al. Cystic and Neoplastic Lesions in Pericoronal Follicles of Asymptomatic Third Molars: A Systematic Review and Meta-Analysis. J Oral Maxillofac Surg. 2026 May 1 (online ahead of print). PMID 42144023
5. Mello FW, Melo G, Kammer PV, Speight PM, Rivero ERC. Prevalence of odontogenic cysts and tumors associated with impacted third molars: A systematic review and meta-analysis. J Craniomaxillofac Surg. 2019;47(6):996-1002. PMID 31005378
6. Alqahtani ND, et al. Retention of Asymptomatic Impacted Third Molars: Effects on Alveolar Bone at the Distal Surface of Second Molars over Time. Diagnostics (Basel). 2025;15(13):1643. PMID 40647642
7. Schmidt J, Kunderova M, Pilbauerova N, Kapitan M. A Review of Evidence-Based Recommendations for Pericoronitis Management and a Systematic Review of Antibiotic Prescribing for Pericoronitis among Dentists. Int J Environ Res Public Health. 2021;18(13):6796. PMID 34202699
8. Bailey E, Kashbour W, Shah N, Worthington HV, Renton TF, Coulthard P. Surgical techniques for the removal of mandibular wisdom teeth. Cochrane Database Syst Rev. 2020;7(7):CD004345. PMID 32712962
9. Kang F, Sah MK, Fei G. Determining the risk relationship associated with inferior alveolar nerve injury following removal of mandibular third molar teeth: A systematic review. J Stomatol Oral Maxillofac Surg. 2020;121(1):63-69. PMID 31476533
10. Bussolar R, et al. Predictive factors in tomographic imaging for inferior alveolar nerve injury during third-molar surgery: A systematic review and meta-analysis. J Am Dent Assoc. 2026 Aug. PMID 41770179
11. Complications in coronectomy procedures for removal of lower third molars in contact with the mandibular canal: systematic review and meta-analysis of clinical trials. Oral Surg Oral Med Oral Pathol Oral Radiol. 2025 Nov. PMID 40562625
12. Vieira WA, et al. Third molar removal and its impact on quality of life: systematic review and meta-analysis. Qual Life Res. 2018;27(10):2477-2489. PMID 29797177
13. Rizqiawan A, et al. Postoperative Complications of Impacted Mandibular Third Molar Extraction Related to Patient's Age and Surgical Difficulty Level: A Cross-Sectional Retrospective Study. Int J Dent. 2022;2022:7239339. PMID 35027927
14. Krüger C, et al. Impacted third molar surgery in older patients-Is patient's age really a risk factor for complications? Clin Oral Investig. 2024;28(10):568. PMID 39375233
15. Lodi G, Azzi L, Varoni EM, et al. Antibiotics to prevent complications following tooth extractions. Cochrane Database Syst Rev. 2021;2(2):CD003811. PMID 33624847
16. Cope AL, Francis N, Wood F, Thompson W, Chestnutt IG. Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults. Cochrane Database Syst Rev. 2024;5(5):CD010136. PMID 38712714
17. Almuqamam M, Gonzalez FJ, Sharma S, Kondamudi NP. Deep Neck Infections. StatPearls. Treasure Island (FL): StatPearls Publishing. PMID 30020634
18. 內部數據：`km-production-queue.html` 三、診所補題區「智齒一定要拔嗎」列（曝光與來源站逐筆可對帳）
19. 醫療法 第 87 條（全國法規資料庫）
20. 編輯框架：本站三層分流結構、分母標註原則、排程問題之處理方式與證據缺口聲明（無外部來源，標示為結構性整理）

Internal citation chain

• How long does an extraction socket take to heal? (KM-DENTAL-01)
• When can I eat or drink after an extraction? (KM-DENTAL-04)
• When can I brush after an extraction? (KM-DENTAL-40)
• Which teeth are the molars? (KM-DENTAL-21)
• How can gum swelling and pain be managed? (KM-DENTAL-05)
• What should I do about toothache? (KM-DENTAL-33)

Publication gate reminder: this symptom-triage/red-flag card needs all four language editions and the GM third opinion before entering `km_entries`. F6 remains UK-system context in every edition.