Assessment of the Soft-Tissue Seal at the Interface between the Base of the Fixed Denture Pontic and the Oral Mucosa

Abstract

Fixed dentures (bridges) are often selected as a treatment option for a defective prosthesis. In this study, we assess the contact condition between the base of the pontic and oral mucosa, and examine the effect of prosthetic preparation and material biocompatibility. The molars were removed and replaced with experimental implants with a free-end type bridge superstructure after one week. In Experiment 1, we assessed different types of prosthetic pre-treatment: (1) the untreated control group (Con: mucosa recovering from the tooth extraction); (2) the laser irradiation group (Las: mucosa recovering after the damage caused by a CO2 laser); and (3) the tooth extraction group (Ext: mucosa recovering immediately after the teeth extraction). In Experiment 2, five materials (titanium, zirconia, porcelain, gold-platinum alloy, and self-curing resin) were placed at the base of the bridge pontic. Four weeks after the placement of the bridge, the mucosa adjacent to the pontic base was histologically analyzed. In Experiment 1, the Con and Las groups exhibited no formation of an epithelial sealing structure on the pontic base. In the Ext group, adherent epithelium was observed. In Experiment 2, the sealing properties at the pontic interface were superior for titanium and the zirconia compared with those made of porcelain or gold-platinum alloy. In the resin group, a clear delay in epithelial healing was observed.

Surface Topography Steer Soft Tissue Response and Antibacterial Function at the Transmucosal Region of Titanium Implant

“…Nevertheless, the surface inertness of zirconia affects its biological activity and subsequently its long-term stability as a dental implant. 17,18 Currently, a new paradigm implies that the osseointegration of dental implants is an immune-driven process leading to the formation of new bone formation surrounding the dental implant surface. 19 With this new concept, a tolerogenic balance could be established between the surface of the dental implant and the peri-implant tissue.…”

Promoted Abutment-Soft Tissue Integration Around Self-Glazed Zirconia Surfaces with Nanotopography Fabricated by Additive 3D Gel Deposition

“…[8][9][10] However, the inert surface of zirconia affects its biological activity and thus the long-term success of zirconia dental implants, so various modification strategies such as physical, chemical, and biological have been explored to enhance the bioactivity of zirconia dental implants. [11][12][13][14][15][16][17] Currently, nanoengineering has been reported to simulate the surface properties of natural tissues to improve surface biological activity, especially with respect to surface topography. [18][19][20][21][22] With the constant evolution of ceramic materials to meet the higher criteria for aesthetics and biocompatibility and achieve long-term effects, a novel monolithic zirconia, referred to as self-glazed zirconia (SZ), fabricated by additive 3D gel deposition, has been developed and put on the market.…”