Extended Emax Endocrown: A Novel Approach for Molar Rehabilitation with Radicular Extension – a Three-Year Follow-Up Case Report

INTRODUCTION

Endocrowns have emerged as a reliable alternative to traditional post-and-core restorations, particularly for endodontically treated molars.¹ However, when a molar has one or more missing walls, achieving sufficient retention and stability remains a concern. This case introduces the Extended Emax Endocrown, a modification of the conventional endocrown, incorporating a radicular extension that utilizes saddle anatomy and increased surface area for additional reinforcement.

This concept diverges from standard endocrowns by extending the restoration 2-4 mm into the root canal, optimizing load distribution and structural integrity. The lithium disilicate (IPS e.max) material provides superior esthetics and fracture resistance, making it a viable long-term solution.

CASE PRESENTATION

Patient Profile

Age/Gender: 22-year-old female

Chief Complaint: Difficulty in chewing and mild discomfort in the upper left region

Clinical Examination:

Endodontically treated maxillary first molar, palatal, mesial and distal wall missing due to previous fracture. There was satisfactory periapical healing with no signs of infection.

And there was already an adequate occlusal clearance for the crown.

Treatment Plan

Given the structural compromise, a conventional endocrown posed a risk of dislodgment due to inadequate cervical sidewalk.^2,3 Instead, an Extended Emax Endocrown was planned, integrating a radicular extension of 3 mm (2-4 mm is recommended in the biggest canals) to enhance stability via saddle anatomy, ensuring a secure fit and better stress distribution.

CLINICAL PROCEDURE

1. Tooth Preparation

The occlusal surface was flattened, and a butt-joint margin5 was established.

The pulp chamber was carefully extended into the radicular space (2-4 mm) without violating the canal walls, forming a saddle-like adaptation.

2. Impression & Fabrication

A digital impression was taken using an intraoral scanner(nobelbiocare).

The Extended Emax Endocrown was designed with CAD/CAM, ensuring precise adaptation.IPS e.max lithium disilicate was selected for its high strength (400 MPa) and esthetic translucency.

3. Lute

The restoration was bonded using a dual-cure self adhesive (3M Relyx U200) resin cement.

Occlusion was carefully adjusted to prevent excessive stress.

FOLLOW-UP & OUTCOME

1-Year Follow-Up: No microleakage, excellent marginal adaptation, and patient satisfaction.

2-Year Follow-Up: No secondary caries, stable occlusion, and intact restoration.

3-Year Follow-Up: The Extended Emax Endocrown remained functionally intact, demonstrating zero debonding, no fracture, and optimal periodontal health.

DISCUSSION

Key Advantages of Extended Emax Endocrowns:

1. Enhanced Stability: The radicular extension reinforces retention, overcoming limitations of standard endocrowns.
2. Optimized Load Distribution: Saddle anatomy aids in even stress distribution, reducing the risk of fracture.^4,5
3. Minimally Invasive: Unlike post-and-core restorations, this technique preserves more dentin, enhancing long-term prognosis.⁶
4. Aesthetic & Functional Superiority: IPS e.max ensures lifelike translucency and durability, making it an ideal choice for molars in comparison with Conventional Restorations

CONCLUSION

The Extended Emax Endocrown represents a significant advancement in the restoration of structurally compromised molars. By incorporating a 2-4 mm radicular extension, this technique enhances stability and longevity, as evidenced by the successful three-year follow-up. This case highlights the potential of lithium disilicate restorations in providing aesthetic, functional, and durable solutions for endodontically treated teeth with compromised walls.

Clinical Significance

This technique can be a game-changer in prosthodontic rehabilitation, particularly for molars with missing walls, eliminating the need for aggressive post-and-core restorations while maintaining structural integrity and longevity.

REFERENCES