Immunohistochemical Results of Soft Tissues around a New Implant Healing-Abutment Surface: A Human Study

Abstract

Although, the high success rate of implant rehabilitation treatment, the biological complications such as bone loss and peri-implantitis are still present. The creation of a coronal biological seal between the implant and the oral tissues seems to be a crucial point on preserving dental implants. The objective of this study was to immunohistochemically analyze the behavior of peri-implant soft tissues around a new implant healing-abutment surface on humans. A total of 30 soft tissue biopsies were collected after a healing period of 30 (±7) days, to analyze the expression of inflammatory (cluster of differentiation 63 (CD63), human neutrophil peptides 1–3 (HPN1–3)) and junctional (E-cadherin, occludin, and β-catenin) markers, on soft tissues around laser treated and machined alternated healing abutments. The evaluation demonstrated the whole area of the soft tissues adherent to the laser treated surface with a regular morphology. While several stress hallmarks in correspondence of machined surfaces were shown such as: (a) An irregular, disrupted, and discontinued basal membrane with an increased inflammation evident both the epithelial and connective tissues; (b) the absence or defective proper keratinization process of the external layer, and (c) damages in the cell to cell interaction. In conclusion, the laser treated surface is preferable to maintain the integrity and functionality of the gingiva epithelium.

Gingival Response to Dental Implant: Comparison Study on the Effects of New Nanopored Laser-Treated vs. Traditional Healing Abutments

“…The general inflammatory status that affect the gingival epithelium leads also to the increase in CK-18 and CK-19 expression, in line with previous studies that showed the overexpression of these two cytokeratins in junctional epithelium flogosi [ 45 , 46 ] and high positivity of CK19 in the epithelium inside the periodontal pocket and in the inflamed gingival epithelium [ 22 ]. Moreover, CK-19 expression is known to be directly proportional to the degree of proliferative activity and inversely proportional to E-cadherin [ 47 , 48 ]: accordingly, it has already been reported that E-cadherin levels are dramatically downregulated in the epithelium surrounding the machined titanium surfaces [ 8 ].…”

“…Recently, it has been reported through histological findings that the gingiva adherent to this new laser-treated surface keeps a regular morphology in all its parts, while the region of the gingiva adherent to the machined surfaces shows several stress hallmarks, including highly inflamed areas with neutrophilic infiltration [ 8 ]. The authors concluded that the use of laser-treated surface on healing abutment could positively influence the healing of peri-implant soft tissues and it is preferable to maintain the integrity and functionality of the gingiva epithelium.…”

“…After the healing period (30 ± 7 days), before starting with the prosthetic restoration of the fixtures, an impression was taken of the small-diameter Has, and circular sections (diameter 5 mm) soft tissues around them were retrieved for analysis as previously reported [ 8 ]. A total of 30 samples were retrieved: 15 of them were treated for quantitative real time PCR (qPCR), the other 15 were treated for immunohistochemical analysis.…”

“…After incubation, samples were washed and treated by DAB substrate. At the end of the process, slides were counterstained with hematoxylin-eosin [ 8 ]. Immunofluorescence staining was performed by blocking aspecificity and retrieving the antigen first, and incubating then the section with the primary anti-human Keratin 18 (2 µg/mL), or anti-human Keratin 19 (1:100) or anti-human MMP9 (1:200) antibodies overnight at 4 °C, as previously reported [ 60 ].…”

“…The resolution of inflammation during the inflammatory phase of wound healing, together with soft tissue attachment, is essential to avoid peri-implantitis and achieve long-term implant success [ 5 , 6 , 7 ]. Thus, novel materials and surface modifications are continuously developed to improve the clinical performance of dental abutments and implants [ 8 , 9 ].…”