Feasibility of Immediate Implant Placement in Maxillary First Premolars: Prediction of Implant Locations Using Restorations-A Radiographic Study.

Purpose: To evaluate the suitability of maxillary premolars for immediate implant placement (IIP). Based on prosthetically driven treatment planning, a simple classification system was developed.

Materials and methods: In total, 150 CBCTs of maxillary first premolars were analyzed in BlueskyBio software. The topographic position of the tooth was determined by analyzing the dimensions of the buccal and lingual cortical plates, the distance between the buccolingual plates, and the residual bone height from the root apex to the floor of the sinus. Virtual placement of an implant was carried out such that the implant would be positioned 1 mm apical to the buccal bone crest, would engage 3 mm of bone apical to the root apex, and would have a trajectory so that the abutment access was from the central fossa. Four categories were identified, and the classification was proposed.

Results: It was observed that 74% of cases had buccal bone < 1 mm and 26% had buccal bone > 1 mm. It was also observed that 79% cases had an average distance > 3 mm between the root apex and maxillary sinus (with 21% of cases < 3 mm). The categorizations of implant placement were as follows: Type 1 (24%), Type 2 (56.6%), Type 3 (43.3%), and Type 4 (0%).

Conclusions: In the majority of maxillary first premolars, IIP is possible with the implants to be placed in the palatal sockets or the furcation area. In cases where the buccal plate thickness is inadequate, simultaneous grafting should be considered between the implant and buccal plate.