Clinical Evaluation of Two Types of Transalveolar Sinus Floor Elevation

Background: Implant placement in the posterior maxilla is always troubled by the insufficient bone volume. Trans-alveolar sinus floor elevation (TSFE) has been proven a predictable surgical procedure to increase the bone height in the posterior maxilla. However, questions as the necessity of the bone grafting is necessary during the sinus lift and could the TSFE be performed when the residual bone height is below 5mm are still being debated. Besides, high-quality evidence on comparing the clinical outcome of transalveolar sinus floor elevation with osteotome and modified sinus floor elevation with crestal non-cutting drills is limited.

Methods/Design: 120 adult patients who fit the inclusion criterions are being recruited from the first clinical division, School and Hospital of Peking University (Beijing, China). All the patients are assigned into four groups according a table of random numbers. Participants receive 1) TSFE using osteotomes with bone grafting; 2) TSFE using osteotomes without bone grafting; 3) modified TSFE with bone grafting; and 4) modified TSFE without bone grafting. The clinical operators will be concealed with the assignment until the beginning of surgical procedures. In a one year follow up period, implant survival rates, complications, implant stability, bone remodeling around the implant and patient-reported outcome (visual analogue scale for intraoperative discomfort and postoperative pain) are observed and documented. The implant stability is gauged by the resonance frequency analysis for 7 times (2, 4,8,12,16,26,52 weeks). And the bone remodeling is observed and compared by CT scan.

Discussion: The result of the trial will support a better decision making in atrophy posterior maxilla when implant placement is needed. If favorable, the use of the modified TSFE would achieve as ideal outcome as the traditional TSFE but with less trauma and postoperative discomforts. Besides, whether the bone graft procedure is necessary for the TSFE will also be discussed.


Eligibility Criteria:
Inclusion Criteria:

* patients who is more than 18 years old;
* patients have lost a single tooth or several teeth in the posterior area of the maxilla, the tooth has/have been extracted for more than three months;
* The residual bone height was between 3mm to 6mm;
* The width of the alveolar ridge could contain the implant with standard diameter;
* The general and local status of patient are suitable for implant placement and sinus floor elevation;
* The patient who is willing to sign the informed consent and to follow the experimental follow-up rules.

Exclusion Criteria:

* Uncontrolled systemic diseases as diabetes, hypertension and so on;
* Uncontrolled local diseases as periodontal disease or muco- cutaneous disease;
* Heavy smoker (more than 10 cigarettes /day)
* Patients who is suffering rhinitis, sinusitis; or rather large cyst is found in the maxillary sinus
* The bone density of the maxillary posterior region is too poor to maintain the initial stability of the implant
* The target of the implant site once received implant therapy or bone grafting
* Patient with psychogenia or incapable to understand and obey the doctors' instruction.