Root Resection & Hemisection
when one bad root doesn't have to mean losing the tooth
If a single root of a multi-rooted molar is the problem, removing just that root — and keeping the rest of the tooth in function — is often more conservative than extracting the whole tooth and placing an implant. This is the patient guide to when that works, when it doesn't, and what 50 years of follow-up evidence actually shows.
What the two procedures actually are
Multi-rooted molars are the only teeth in the mouth where this option exists. Each root is, in a meaningful sense, an independent unit — with its own canal system, surrounding bone, and periodontal attachment. A problem in one root does not automatically mean the others are failing.
Root resection (upper molars)
Upper molars typically have three roots: mesiobuccal, distobuccal, and palatal. One root is sectioned away from the crown and removed; the remaining two roots continue to support the natural crown. Also called root amputation. The mesiobuccal root is the most commonly resected — it is the root most often involved in combined endo-perio lesions.
Hemisection (lower molars)
Lower molars have two roots: mesial and distal. The tooth is divided through the furcation and the diseased half is removed; the remaining half functions as a single-rooted tooth restored with a crown. When both halves are kept and restored as two separate teeth, the procedure is called bicuspidization.
Who is a good candidate
The single highest predictor of outcome — across every long-term follow-up study from Klavan 1975 through Park 2009 — is honest candidacy assessment. The framework below is the one we use in our office.
Good candidate when
- Pathology is genuinely confined to ONE root — vertical fracture in one root, furcation perforation, severe localized bone loss, or a combined endo-perio lesion on one root.
- The retained root(s) have adequate length, divergence, and surrounding bone.
- The retained root(s) are endodontically treatable — confirmed by completing the root canal BEFORE the sectioning.
- The tooth has neighbors on both sides — it isn't a terminal abutment carrying a bridge.
- You can keep the modified furcation area clean with floss threaders or interproximal brushes.
- Occlusal forces are reasonable — no severe bruxism or parafunction on the tooth.
Wrong procedure when
- Fused or convergent roots that can't be cleanly sectioned.
- Generalized periodontal disease — more than one root involved, or active perio elsewhere in the mouth.
- Heavy bruxism or parafunctional load on the tooth.
- Terminal bridge abutment with no distal tooth — the restorative biomechanics are usually unfavorable.
- Poor home-care or a patient who can't or won't maintain the modified furcation.
- Endodontic prognosis on the retained roots is uncertain — re-treatment failures, calcified canals that can't be negotiated, or vertical fractures extending beyond the targeted root.
How the procedure is done, step by step
The technical work happens in one visit, but the planning and the endodontic preparation matter at least as much as the sectioning itself.
CBCT 3D Imaging & Periodontal Mapping
We map the exact 3D anatomy of every root, the interradicular bone, and the furcation on a low-dose CBCT scan. Periodontal probing depths and bone levels on the retained roots are recorded — if the remaining roots can't support the tooth alone, resection is the wrong procedure.
Definitive Root Canal on the Retained Root(s)
The root(s) that will stay are root-canal treated first, typically 4–8 weeks before the sectioning. Verifying the endodontic prognosis on the retained roots BEFORE committing to surgery is the single most important way to prevent a doomed outcome.
Local Anesthesia & Microsurgical Access
On the day of resection, the area is fully numbed under local anesthesia. A small flap is reflected to expose the furcation under the Zeiss OPMI surgical microscope (up to 25× magnification).
Sectioning at the Furcation
The crown is sectioned through the furcation with a fine bur under copious irrigation. For a maxillary molar root resection, the diseased root is detached from the crown and removed cleanly. For a mandibular hemisection, the tooth is divided in half and the diseased half elevated out.
Site Debridement & Recontouring
Granulation tissue is removed from the socket. The remaining crown is recontoured so the furcation area is cleansable — a tooth you can't clean is a tooth that will re-infect. The flap is repositioned with fine sutures.
Interim Restoration & Definitive Crown
An interim restoration protects the tooth for 4–8 weeks of soft-tissue healing. Your general dentist then places a definitive full-coverage crown that splints and seals the retained portion. 6- and 12-month follow-ups confirm periodontal stability.
What the 10-year evidence actually shows
Root resection has 50+ years of published outcome data — longer than implants. The published numbers span a wide range, and that range is the most important thing for a patient to understand: case selection drives outcome more than the procedure itself.
- Langer 1981 followed 100 resected teeth over a decade and reported a ~38% loss rate over 10 years[1] — primarily from root fracture and recurrent periodontal disease. This was the cohort that established the realistic failure modes; it included loosely-selected cases that today wouldn't be considered candidates.
- Klavan 1975 — the foundational clinical-observation paper on root amputation in maxillary molars[2] — set out the original indication/contraindication framework that the field still uses. Klavan flagged terminal-abutment cases and uncleansable furcations as the dominant failure scenarios.
- Bühler 1988 followed 28 root-resected molars and reported ~68% still in function at 10 years[3]. Bühler's failure analysis again pointed at root fracture and endodontic failure on the retained root — the same patterns Langer described.
- Park 2009 — a 10-year retrospective on the factors that drive resection outcome[4] — identified parafunctional occlusal load, inadequate underlying endodontic treatment, and poorly-placed crown margins as the three strongest predictors of failure. Technique itself was not in the top three.
- Fugazzotto 2001 — the largest head-to-head comparison of resected molars vs. molar-position implants in the same private practice — reported ~96% cumulative survival for carefully-selected resected molars vs. ~97% for implants over up to 15+ years[6]. The honest read of that paper is not that surgery is "better than" an implant; it is that, in the right tooth, neither is clearly better, so the more conservative natural-tooth option is reasonable.
Numbered references [1]–[6] are listed in the Clinical reference section at the bottom of this page.
Resection / hemisection vs. extraction + implant vs. apicoectomy
These are the three options usually on the table when one root of a multi-rooted molar is the problem. They are not interchangeable — each addresses a different clinical pattern.
| Factor | Resection / Hemisection | Extraction + Implant | Apicoectomy |
|---|---|---|---|
| Approach | Section the tooth at the furcation; remove only the diseased root or half. | Remove the whole tooth; place a titanium implant after bone heals; restore with implant crown. | Microsurgical removal of just the root TIP plus a bioceramic root-end seal; whole tooth stays. |
| Best when | An entire root (not just the tip) is the problem — vertical fracture, furcation perforation, severe localized bone loss on one root. | Multiple roots compromised, fused roots that can't be sectioned, generalized perio, or the tooth is non-restorable. | Infection is at the root TIP only, on a previously-treated tooth, where a good crown shouldn't be disturbed. |
| Published 10-yr survival | ~60–96% — case-selection dependent. ~96% in well-selected cohorts[6]; ~68% in mixed cohorts[3]. | ~93–97% implant survival in molar positions. Success (no peri-implantitis) is somewhat lower. | ~94% with modern microsurgery (Setzer 2010); ~59% with the older 1960s technique. |
| Recovery | Most patients work next day; sutures out at 1 week; interim restoration 4–8 weeks; definitive crown after. | 3–7 days after extraction; 3–6 months osseointegration; then crown. | Most patients work next day; sutures out at 1 week; existing crown stays. |
| Typical fee (specialist, 2026) | $1,400–$2,200 surgical fee + crown by general dentist (often-required RCT on retained root billed separately). | $4,500–$7,500 + possible bone graft. | $1,800–$2,800. |
| Preserves the natural tooth? | Partially — keeps the remaining root(s) and the periodontal ligament. | No — the tooth and its periodontal ligament are removed. | Yes — whole tooth and existing crown are preserved. |
See also our patient guides to apicoectomy, non-surgical retreatment, and the companion blog post "Can one bad root mean losing the whole tooth?".
What recovery actually feels like
First 24 hours
Numbness wears off in 2–4 hours. Mild ache as it wears off — managed with ibuprofen 600 mg every 6 hours for the first day. Minor oozing for a few hours is normal; bite gentle gauze pressure as instructed. Soft diet only.
Days 2–7
Most patients return to work or school the day after surgery. Some swelling on the cheek for 2–3 days is normal; ice for the first day, warm compress after that. Avoid chewing on the surgical side. Sutures removed (or self-dissolve) at the 1-week check.
Weeks 2–8
Soft tissue heals. Your interim restoration protects the tooth and helps the gum recontour around the new furcation. Cleansability work begins — we'll teach you the floss-threader and interproximal-brush technique for the modified furcation.
Months 2–12
Your general dentist places the definitive full-coverage crown. We follow up at 6 and 12 months to verify periodontal stability, check the retained root(s) on x-ray, and confirm bone fill. Long-term, the tooth is yours — typical 10-year survival in well-selected cases is about 85–96%.
Frequently asked questions
What is the difference between root resection and hemisection?
Both procedures remove part of a multi-rooted tooth to save the rest. Root resection (also called root amputation) removes ONE root of a maxillary molar while leaving the crown intact above the remaining 1–2 roots. Hemisection is performed on a lower (mandibular) molar — the tooth is split in half through the furcation and the diseased half is removed, leaving the healthy half as essentially a single-rooted tooth that's restored with a crown.
How successful is root resection or hemisection?
Reported survival ranges widely depending on patient selection. Bühler's 10-year evaluation found about 68% of resected teeth still in function at 10 years. Fugazzotto's practice-based study reported about 96% cumulative survival at up to 15 years for carefully selected resected molars — comparable to molar implants in the same study (about 97%). The honest range to quote a patient is: 60–95% at 10 years, with the high end requiring strict candidacy.
Is root resection or hemisection a good alternative to an implant?
Sometimes, yes — and increasingly, no. In the right patient (isolated single-root pathology, good remaining bone, no bruxism, excellent hygiene), Fugazzotto 2001 showed resection survival matches implant survival. In the wrong patient (generalized periodontitis, bruxism, poor hygiene, fused roots), an implant is more predictable. This is a shared decision that requires CBCT imaging, periodontal evaluation, and an honest conversation about long-term prognosis.
Does the tooth need a root canal before resection?
Yes. The retained root(s) must have a successful root canal — ideally completed and verified BEFORE the sectioning, so we know the endodontic prognosis is good before we commit to the surgical step. Resecting a tooth whose remaining root then fails endodontically is the worst-case outcome and is preventable.
How long does the procedure take and what's the recovery like?
The surgical sectioning itself is typically 60–90 minutes under local anesthesia. Most patients return to normal activity the next day. Sutures come out at one week. A temporary or interim restoration protects the tooth for 4–8 weeks while the soft tissue heals, then your general dentist places the definitive crown. Some discomfort and minor swelling for 2–3 days is normal and is managed with ibuprofen.
Will my insurance cover root resection or hemisection?
Most PPO dental plans cover the procedure under CDT codes D3450 (root amputation) or D3920 (hemisection) when accompanied by a narrative and CBCT documentation showing single-root pathology. Coverage levels vary by plan (typically 50–80% of the specialist fee). Our office files pre-authorization on request and provides a clear written estimate before treatment.
What if the resection fails — can I still get an implant later?
Yes, in most cases. When a resected tooth eventually fails, the remaining bone is usually sufficient for an implant — sometimes after a short healing period or a small graft. Saving the tooth first does not burn the implant bridge.
Further reading
- · Apicoectomy & endodontic microsurgery — the related procedure for infection at the root tip.
- · Non-surgical root canal retreatment — when re-cleaning the canals from inside is the better option.
- · When to get a second opinion on a recommended extraction.
- · "Can one bad root mean losing the whole tooth? Not always." — the companion patient-facing blog post.
Considering this option?
Dr. Kung offers honest second-opinion consultations on multi-rooted molars where an extraction has been recommended. We'll review your CBCT (or take one if needed), walk through the candidacy criteria above, and tell you straight whether resection is genuinely the right choice for your tooth — or whether an implant or apicoectomy is the more honest path forward.