Long-Term Outcome of IS-III Implant Placement with Crestal Sinus Lifting in the Posterior Maxilla

Case Summary 🔎

Patient Information

•Age/Gender: 53-year-old, Male

•Past Medical History: History of Hypertension under medication

•Drug allergy: None

•Chief complaint: "I have the missing teeth on the upper left area."

Patient Information

This case involves a 53-year-old male patient with missing maxillary left posterior teeth (#24, #25, and #26). Crestal sinus lifting was performed using the S-reamer from the SCA kit. At sites #24 and #25, implants were placed without bone grafting, corresponding to Dr. Heo’s Sinus Classification II, while site #26 required bone grafting and was classified as Sinus Classification III. CMI IS-III implants were placed with sufficient primary stability, achieving insertion torque values of 35–40 N/cm, and the definitive prostheses were delivered two months after surgery. Annual clinical and radiographic follow-up examinations were conducted from 2017 to 2025, demonstrating stable peri-implant conditions and favorable long-term outcomes.

Patient Information

1. Flapless osteotomy preparation and crestal sinus lifting using an S-reamer

2. Placement of CMI IS-III implant at #24,25,26

3. Delivery of the definitive restoration 2 months after surgery

4. Annual clinical and radiographic follow-up

Case Presentation

1️⃣ Pre-Op

• Pre-operative radiograph and intraoral photograph shows well-healed alveolar ridge.

  

  

2️⃣ Surgery / Final Restoration

• Tissue punch used for flapless surgery.

  

  

  
  
  

• Crestal sinus lifting performed using the S-reamer from the SCA kit without membrane perforation.

  

  
  
  

• Sinus membrane elevation without bone grafting at #24 and #25 (Dr. Heo’s Sinus Classification II), with bone grafting performed at #26.

  

                                                      Dr. Heo's Sinus Classification

• CMI IS-III implants were placed at sites #24 (Ø4.0 × 10 mm), #25 (Ø4.0 × 11 mm), and #26 (Ø5.0 × 10 mm) in D332 bone density, achieving stable primary stability with insertion torque values of 40 N/cm at #24 and #25, and 35 N/cm at #26.

  

  
  
  

• Crestal bone grafting was performed at sites #24 and #25, followed by healing abutment connection.

  

  
  
  

• Periapical radiograph and panoramic radiograph  showing inferior cortical fixation of implants at #24, #25, and #26

  

  

• Definitive prostheses were delivered two months after surgery.

  (March 22,2017)

  

  

3️⃣ Annual follow-up

From January 2017 to December 2025, annual follow-up evaluations showed stable long-term maintenance with no evidence of bone loss.

Conclusion

This case demonstrates that crestal sinus lifting using the S-reamer, with or without bone grafting based on sinus classification, can provide predictable outcomes in the posterior maxilla. IS-III implants achieved sufficient primary stability and supported successful prosthetic rehabilitation. Long-term follow-up over eight years showed stable peri-implant conditions without marginal bone loss, confirming the reliability of this treatment approach.