Effect of Fixture Thread Depth on Accuracy of Immediate Implant Placement Using Dynamic Navigation

The goal of this clinical trial is to compare the placement accuracy in immediately placed implants using dynamic navigation between deep-threaded and regular-threaded implants in partially edentulous patients. The main question it aims to answer is: is there a difference in implant placement accuracy between deep-threaded and regular-threaded implants using dynamic navigation? Participants will receive implants placed immediately under dynamic guidance. Researchers will compare type of implant thread (Straumann BLT versus Straumann BLX) to see if there are significant differences in placement accuracy.

The initial visit will comprise a thorough clinical examination and panoramic radiograph acquisition. Hopeless teeth resulting from trauma, periapical abscess, and periodontitis will be evaluated to see if extraction indications are met. When extraction indications were met, patients will be evaluated for suitable bone height for immediate implant placement. When bone height was suitable, patients will be asked to take a preoperative CBCT scan.

After tooth condition and bone volume evaluations, patients with adequate bone volume for immediate implant placement will be enrolled and randomly assigned to one of two groups: deep-threaded or regular-threaded.

The following implant placement accuracy parameters will be recorded using postoperative intraoral scanning superimposition: Global platform deviation (measured in millimeters), lateral platform deviation (measured in millimeters), global apex deviation (measured in millimeters), apex depth deviations (measured in millimeters), and angular deviation (measured in degrees). Primary implant stability will be measured immediately after implant insertion and measured in both insertion torque value and implant stability quotient. Radiographic bone-implant contact will be measured with a 3D implant model reconstruction method using coDiagnostiX and the contact area will be calculated using 3-matic Research as previously reported. Marginal bone loss will be measured using ImageJ with periapical radiographs taken 3 months and 1-year post-op. Implant survival will be monitored starting from the final prosthesis delivery onwards. Complications (biological, technical, and implant loss) will be recorded accordingly. Patient satisfaction will be documented with a Mandarin Chinese version of the Short Form Patient Satisfaction Questionnaire (PSQ-18) upon final prosthesis delivery.

Eligibility Criteria:
Inclusion Criteria:

* Hopeless teeth that require extraction
* No systemic diseases
* Smoking (\<10 cigarettes/day)
* Full-mouth bleeding and full-mouth plaque index lower than or equal to 25%
* Fresh extraction sockets with at least 3 fully intact socket walls
* At least 4 mm of bone beyond the root apex
* Meets one of the following:
* Single immediate placement site in the maxillary esthetic zone \[15-25 (FDI classification)\].
* Two or more nonconsecutive immediate placement sites in the maxillary esthetic zone \[15-25 (FDI classification)\].
* Two or more consecutive immediate placement sites in the maxillary esthetic zone \[15-25 (FDI classification)\].

Exclusion Criteria:

* General medical (American Society of Anesthesiologists, ASA, class III or IV) and/or psychiatric contraindications
* Pregnancy or nursing
* Any interfering medication such as steroid therapy or bisphosphonate therapy
* Alcohol or drug abuse
* Heavy smoking (\>10 cigarettes/day)
* Radiation therapy to head or neck region within 5 years
* Untreated periodontitis
* Refuse to participate in this trial