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

• Published in: Materials Vol. 14; no. 14; p. 3997
• Main Authors: Atsuta, Ikiru, Narimatsu, Ikue, Morimoto, Taichiro, Cheng, Chi-Hsiang, Koyano, Kiyoshi, Ayukawa, Yasunori
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 16.07.2021; MDPI
• Subjects: Adhesion; adhesion molecule; Adhesives; Antibodies; Biocompatibility; Carbon dioxide; Carbon dioxide lasers; Connective tissue; Dental materials; Dentures; epithelial seal; Experiments; fixed denture; Gold base alloys; Heparan sulfate; Laboratories; Microscopy; oral mucosa; Platinum; Porcelain; Prostheses; Radiation damage; Recovering; Resins; Sealing; Superstructures; Surgical implants; Titanium; Transplants & implants; Variance analysis; Zirconium dioxide; St Louis Missouri; United States > US; Temecula California; Japan; epithelial seal; fixed denture; oral mucosa; adhesion molecule
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14143997

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 CO 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.