Selective Root Resection of Mandibular First and Second Molars for Management of Extensive Carious Lesions: A Case Report

INTRODUCTION

The preservation of natural dentition has always been a central objective in dental practice. With the advancement of modern dentistry, there has been a paradigm shift from extraction-based treatment approaches toward more conservative and biologically sound procedures aimed at maintaining the natural tooth structure whenever possible. Among such treatment modalities, hemisection has emerged as a valuable and effective option in the management of compromised multirooted teeth, particularly mandibular molars.^1,2

Hemisection refers to the surgical separation of a multirooted tooth into two halves, followed by the removal of one root along with its associated coronal portion, while retaining the healthy and structurally sound root. This procedure is most commonly performed in mandibular first and second molars due to their anatomical configuration, which typically consists of well-separated mesial and distal roots. Teeth 36 and 37, being key components of the posterior occlusion, play a crucial role in mastication and maintenance of vertical dimension, making their preservation highly desirable.¹

Multirooted teeth are often subjected to complex pathological conditions involving both periodontal and endodontic components. Advanced periodontal disease, characterized by deep periodontal pockets and furcation involvement, is one of the primary reasons for the compromise of mandibular molars. Furcation involvement, particularly Grade II and Grade III, poses a significant challenge for conventional periodontal therapy due to the difficulty in achieving adequate debridement and maintenance. In such scenarios, hemisection provides a means to eliminate the diseased root while preserving the rest of the tooth, thereby improving access for oral hygiene and enhancing periodontal prognosis.^3,4

In addition to periodontal indications, hemisection is also indicated in cases of localized endodontic failure, vertical root fractures, root perforations, and extensive carious destruction confined to a single root. Endodontic failures in multirooted teeth may sometimes be restricted to one root due to anatomical complexities such as accessory canals, calcifications, or procedural errors. Instead of extracting the entire tooth, removal of the affected root can effectively resolve the pathology while retaining the functional portion of the tooth.^2,5

The decision to perform hemisection requires careful case selection and thorough clinical and radiographic evaluation. Factors such as root anatomy, degree of bone support, crown-to-root ratio, strategic importance of the tooth, and the patient’s oral hygiene status must be considered. Teeth with well-diverged roots, minimal root fusion, and adequate periodontal support of the remaining root are considered ideal candidates for this procedure. Conversely, poor oral hygiene, unfavorable root morphology, or insufficient bone support may compromise the long-term success of hemisection.⁶

One of the major advantages of hemisection is that it allows preservation of natural tooth structure and the surrounding alveolar bone. This is particularly important in maintaining proprioception, which is often lost with prosthetic replacements such as dental implants. Additionally, hemisection is a relatively cost-effective procedure compared to implant therapy, making it a suitable option for patients with financial constraints or contraindications to surgical implant placement.⁷

From a biomechanical perspective, the retained root must be capable of withstanding occlusal forces after the procedure. Proper occlusal adjustment and prosthetic rehabilitation are essential to ensure favorable load distribution and prevent complications such as root fracture or periodontal breakdown. Full-coverage restorations, often in the form of crowns or fixed partial dentures, are commonly employed to restore function and esthetics following hemisection.^1,8.

The success of hemisection is highly dependent on a multidisciplinary approach involving endodontic, periodontal, and prosthodontic considerations. Adequate endodontic treatment of the retained root is crucial to eliminate infection and provide a stable foundation. Periodontal management, including thorough debridement and maintenance, is essential to ensure long-term stability. Furthermore, well-designed prosthetic rehabilitation plays a key role in restoring masticatory function and preventing undue stress on the remaining tooth structure.^3,8.

Despite its advantages, hemisection is not without limitations. The procedure requires precise surgical technique and careful postoperative management. Patient compliance with oral hygiene practices and regular follow-up visits is critical for long-term success. Potential complications include recurrent caries, root fracture, endodontic failure, and periodontal deterioration. However, with proper case selection and meticulous execution, hemisection has been shown to have a high success rate and favorable prognosis.^5,9.

In recent years, the increasing popularity of dental implants has led to a decline in the use of tooth-preserving procedures such as hemisection. However, it is important to recognize that implants may not always be the first line of treatment, especially when a portion of the natural tooth can be retained and restored successfully. Preservation of natural dentition should remain a priority whenever feasible, as it offers biological and functional advantages over artificial replacements.^7,10

The present case report aims to highlight the clinical application and outcome of hemisection in the management of a compromised mandibular molar in a 35-year-old male patient. It emphasizes the importance of proper diagnosis, case selection, and interdisciplinary treatment planning in achieving successful outcomes with this conservative approach.

CASE REPORT

A 35-year-old male patient reported to the Department of Conservative Dentistry and Endodontics with the chief complaint of food lodgement and intermittent pain in the lower left posterior region for the past 4–5 months. The pain was described as dull, non-radiating, and aggravated during mastication. The patient’s medical history was non-contributory.

On intraoral examination, tooth 36 revealed a previously endodontically treated tooth with a large coronal restoration. However, there was evidence of recurrent caries involving the proximal surfaces with associated gingival inflammation. Periodontal probing revealed increased pocket depth in the furcation region. Tooth 36 exhibited mild tenderness on percussion and Grade I mobility. Tooth 37 showed deep mesioproximal caries with food impaction and gingival inflammation, but it was not tender on percussion.

Radiographic examination (RVG) revealed that tooth 36 was previously treated endodontically, with obturated canals and a coronal restoration in place. However, there was significant radiolucency associated with the distal root, along with bone loss in the furcation region, suggesting localized periodontal destruction and possible endodontic-periodontal involvement. The mesial root of 36 showed comparatively better bone support. In relation to tooth 37, the radiograph showed proximal caries extending toward the pulp, with greater destruction of the mesial root structure and associated periodontal bone loss, while the distal root appeared relatively intact with adequate support.

Based on the clinical and radiographic findings, a diagnosis of previously treated tooth with secondary caries and localized periodontal involvement in relation to tooth 36, and deep proximal caries with pulpal involvement in relation to tooth 37, was made.

Considering the strategic importance of the teeth and the localized nature of the pathology, a conservative treatment plan involving hemisection was formulated. It was decided to remove the distal root of tooth 36, which showed significant bone loss despite prior endodontic treatment, and the mesial root of tooth 37, which was severely compromised due to extensive caries and periodontal involvement, while preserving the remaining roots.

Endodontic treatment was evaluated in tooth 36, and the obturation in the mesial root was found to be satisfactory; hence, it was retained. Root canal treatment was performed for the distal root of tooth 37 (the root planned to be retained), followed by biomechanical preparation and obturation .

CLINICAL PROCEDURE

Following completion of endodontic therapy, the surgical phase was carried out under local anesthesia. A full-thickness mucoperiosteal flap was reflected to expose the furcation area. Tooth 36 was sectioned buccolingually, and the distal root along with its associated coronal portion was carefully removed. Similarly, tooth 37 was sectioned, and the mesial root was atraumatically extracted. Thorough debridement and curettage of the surgical site were performed, followed by irrigation with sterile saline. The retained roots (mesial root of 36 and distal root of 37) were contoured and smoothened to eliminate plaque-retentive areas and to facilitate periodontal healing.

The flap was repositioned and secured with interrupted sutures. Postoperative instructions were given, and the patient was prescribed antibiotics, analgesics, and chlorhexidine mouth rinse. Sutures were removed after one week, and healing was uneventful.

After a healing period of 6–8 weeks, prosthetic rehabilitation was carried out. The retained portions of teeth 36 and 37 were restored with full-coverage crowns designed to ensure proper occlusal load distribution and functional stability.

Follow-up at 3 months and 6 months revealed that the patient was asymptomatic, with no evidence of mobility or periodontal inflammation. Radiographic evaluation showed satisfactory bone healing and stable periodontal condition around the retained roots. The patient maintained good oral hygiene, and the overall treatment outcome was considered successful.

After a healing period of 6–8 weeks, the patient was planned for prosthetic rehabilitation. The retained portions of teeth 36 and 37 were prepared to receive full-coverage restorations to ensure proper occlusal load distribution and long-term functional stability.

DISCUSSION

Hemisection is a conservative treatment modality that allows selective removal of diseased roots in multirooted teeth while preserving the healthy portion, thereby maintaining function and alveolar bone support. In the present case, hemisection was performed on two adjacent mandibular molars, involving removal of the distal root of tooth 36 and the mesial root of tooth 37, based on the extent and location of proximal caries and periodontal involvement. This approach was aimed at eliminating the diseased segments while preserving strategically important tooth structure. Weine stated that “root resection procedures are indicated when one root is severely compromised while the remaining root demonstrates adequate periodontal and endodontic prognosis”¹¹, which justifies the treatment approach adopted in this case.

The decision to remove the distal root of tooth 36 was based on extensive distoproximal caries with associated bone loss, while the mesial root of tooth 37 was removed due to deep mesio proximal caries compromising its structural integrity. Basaraba emphasized that “the key to successful hemisection lies in accurate identification and removal of the affected root while preserving the sound portion of the tooth”.¹² In the present case, selective removal of roots allowed elimination of localized pathology while maintaining sufficient tooth structure to support functional rehabilitation.

Furcation involvement and proximal caries are often interrelated factors contributing to the failure of mandibular molars. Glickman stated that “furcation areas present a unique challenge due to their anatomical complexity and limited accessibility for debridement”.¹³. In this case, the involvement of proximal surfaces extending into the furcation region necessitated removal of the affected roots to improve accessibility and prognosis. Carranza and Newman further reported that “root resection procedures eliminate furcation defects and facilitate improved periodontal maintenance”¹⁴, which was evident in the improved periodontal condition observed during follow-up.

Endodontic management of the retained roots is critical for the success of such procedures. In the present case, endodontic therapy was completed on the retained roots prior to surgical intervention to ensure elimination of infection. Ingle and Bakland stated that “successful root canal therapy is essential for the long-term success of teeth undergoing root resection” ¹⁵ Additionally, Torabinejad emphasized that “failures in root-resected teeth are more commonly due to inadequate endodontic treatment than the surgical procedure itself”.¹⁶ The favorable clinical outcome in this case can be attributed in part to meticulous endodontic management.

From a periodontal standpoint, the removal of the mesial root of 37 and distal root of 36 resulted in improved access for oral hygiene and reduction in periodontal pocket depth. Newell stated that “the primary benefit of root resection is enhanced accessibility for plaque control, which significantly improves long-term prognosis”.¹⁷ The reshaping and contouring of the retained roots further contributed to maintaining periodontal health and preventing plaque accumulation.

Prosthetic rehabilitation following hemisection plays a vital role in restoring function and ensuring longevity of the treated teeth. Rosenstiel et al. stated that “properly designed full-coverage restorations are essential to distribute occlusal forces evenly and protect the remaining tooth structure”.¹⁸ In the present case, restoration of the retained roots with full-coverage crowns helped in achieving functional stability and maintaining occlusal harmony. Proper prosthetic rehabilitation following hemisection is essential to ensure favorable biomechanics and longevity of the retained root structure.

The management of adjacent molars with hemisection, as performed in this case, demonstrates a strategic approach in preserving multiple teeth affected by localized pathology. Fugazzotto reported that “root-resected molars, when properly selected and restored, can exhibit survival rates comparable to dental implants”.¹⁹ This highlights the importance of considering conservative approaches before opting for extraction and implant placement.

However, hemisection remains a technique-sensitive procedure that requires careful planning, execution, and long-term maintenance. Langer et al. stated that “the success of root resection procedures is highly dependent on patient compliance, oral hygiene, and regular follow-up care”.²⁰ In the present case, adherence to postoperative instructions and maintenance protocols played a significant role in achieving favorable clinical and radiographic outcomes.

In summary, the selective removal of the distal root of tooth 36 and mesial root of tooth 37 in this case demonstrates that hemisection can be effectively utilized in managing adjacent molars with localized proximal caries and periodontal involvement. When combined with proper endodontic therapy, periodontal management, and prosthetic rehabilitation, it provides a predictable and conservative alternative to extraction while preserving natural dentition and function.

CONCLUSION

Hemisection is a conservative and reliable treatment modality for managing mandibular molars with localized periodontal and structural compromise. In the present case, selective removal of the distal root of tooth 36 and mesial root of tooth 37 enabled preservation of the remaining roots with satisfactory functional and periodontal outcomes. With appropriate case selection, sound endodontic therapy, and planned prosthetic rehabilitation, hemisection can serve as a predictable alternative to extraction, aiding in the preservation of natural dentition and maintenance of occlusal stability.

REFERENCES