Marginal Bone Level and Bone Thickness Reduction in Delayed and Immediate Implant Placement Protocol 6 Months Post-loading: An Observational Clinical Prospective Study.

Objectives: The aim of this prospective study was to assess marginal bone level (MBL), buccal and palatal bone thickness reduction (BTR) around implants in delayed and immediate placement protocols, 6 months after loading.

Materials And Methods: Twenty-four patients were assigned to two treatment groups, and treated with an immediate (Test) or delayed implant placement (Control). Baseline and 6 months post-loading periapical and Cone Beam Computed Tomography radiographs were used to measure mesial, distal, buccal, and palatal MBL change, and buccal and palatal BTR.

Results: There was no statistically significant difference between groups, in MBL change, mesially ( = 0.4220), distally ( = 0.774), buccally ( = 0.221), and palatally ( = 0.195). There was more MBL change on the buccal side than on the palatal side in both groups, control ( = 0.012) and test ( = 0.005). Buccal bone thickness decreased significantly in both groups, and at all four levels ( < 0.05). Buccal BTR was higher in test implants at 0, 2, and 4 mm ( = 0.005, = 0.0018, = 0.006) on the buccal side, and at 0 mm ( = 0.006) on the palatal side. Implant stability increased in both groups ( < 0.001). A positive correlation was found between insertion torque and stability in the control group ( = 0.024).

Conclusions: Within the study limitations, MBL changes occur around implants and are comparable between groups. More buccal than palatal MBL change occurs in both groups. Buccal BTR is higher in immediate cases. Implant stability augmented in both groups.

Clinical Relevance: This data call for additive therapy to compensate for the expected bone loss, particularly in esthetically demanding cases.

Trial Registration: ClinicalTrials.gov Identifier: NCT04346706 Registered 14 April 2020 - Retrospectively registered, http://www.clinicalTrials.gov.