Histopathologic assessment of soft tissue healing around Polyetheretherketone and Titanium abutments. A Randomized and controlled human study

Aims The establishment of peri-implant mucosa is crucial for dental implant success, involving a sequence of biological events leading to tissue barrier formation. While titanium has been the traditional choice for abutments, alternatives like PEEK show comparable healing outcomes in pre-clinical and clinical studies. This randomized clinical trial aims to compare the histological and inflammatory reactions of Polyetheretherketone (PEEK) and titanium abutments in individuals with partial posterior maxillary edentulism.

Methods Systemically healthy adults were consecutively enrolled. Following implant placement (44x 8mm, 3P implants, B&B Dental, San Pietro in Casale, Italy), participants were randomly assigned to receive either titanium or PEEK abutments. After a healing period of 5 months, a minimally invasive biopsy procedure was performed, and immunohistochemical analysis of inflammatory infiltration was carried out.

Results Twenty-two implants were placed in the posterior maxillary region of enrolled patients. Both abutment groups exhibited similar degrees of inflammatory infiltrate (p > 0.05). Dystrophic calcifications were slightly higher in the PEEK group (p = 0.26). Immunohistochemical analysis revealed comparable percentages of CD3+ T cells, CD20+ B cells, CD38+ and CD68+ cells between the two groups (p > 0.05). A trend of a less marked infiltrate was observed around titanium, particularly at the mesial side (26.66% vs. 6.75%, p = 0.02).

Conclusions PEEK and titanium abutments demonstrated similar peri-implant soft tissue responses. The histological findings did not reveal a significantly increased inflammatory reaction associated with Polyetheretherketone. While a trend of less marked infiltrate around titanium was observed, further long-term observations are crucial for a definitive assessment of PEEK abutment suitability.