Selective infiltrated etching to surface treat zirconia using a modified glass agent

Efficacy and risks of tooth-supported prostheses in the treatment of partially edentulous patients with stage IV periodontitis. A systematic review and meta-analysis

AIM

The aim was to evaluate the efficacy and effectiveness of tooth-supported fixed prostheses in partially edentulous patients with stage IV periodontitis.

MATERIAL AND METHODS

Randomized and controlled clinical trials (RCTs and CCTs) and prospective/retrospective cohort studies or case series were searched in three databases. Survival rate of abutment teeth was considered the primary outcome. Meta-analyses were performed whenever possible.

RESULTS

Twenty-four publications were included. No RCTs or CCTs compared the efficacy of tooth-supported fixed prostheses between patients with severe periodontitis or non-periodontitis patients. Most of the data retrieved were derived from case series. The incidence of abutment-tooth loss after a follow-up period from 2 to 35.4 years was low (n = 17 studies; weighted mean incidence (WMI) = 4.8%; confidence interval (CI) [3.2, 6.5]). The corresponding figure for prostheses failure was WMI = 6.9% (n = 18; 95% CI [4.1, 9.7]). Technical complications seemed to be more frequent than biological complications (caries, endodontic failure, root fracture, etc.). Periodontal outcomes tended to remain stable over time.

CONCLUSION

Tooth-supported fixed prostheses seemed to be a valid treatment approach to restore masticatory function in patients with stage IV periodontitis once periodontal therapy has been accomplished. However, the comparative efficacy of this treatment among periodontitis and non-periodontitis patients is unclear due to the absence of clinical trials.

Adhesion to Zirconia: A Systematic Review of Current Conditioning Methods and Bonding Materials

Background. Reliable bonding between resin composite cements and high strength ceramics is difficult to achieve because of their chemical inertness and lack of silica content that makes etching impossible. The purpose of this review is to classify and analyze the existing methods and materials suggested to improve the adhesion of zirconia to dental substrate by using composite resins, in order to explore current trends in surface conditioning methods with predictable results. Methods. The current literature, examining the bond strength of zirconia ceramics, and including in vitro studies, clinical studies, and a systematic review, was analyzed. The research in the literature was carried out using PubMed and Cochrane Library databases, only papers in English, published online from 2013 to 2018. The following keywords and their combinations were used: Zirconia, 3Y-TZP, Adhesion, Adhesive cementation, Bonding, Resin, Composite resin, Composite material, Dentin, Enamel. Results. Research, in PubMed and Cochrane Library databases, provided 390 titles with abstracts. From these, a total of 93 publications were chosen for analysis. After a full text evaluation, seven articles were discarded. Therefore, the final sample was 86, including in vitro, clinical studies, and one systematic review. Various adhesive techniques with different testing methods were examined. Conclusions. Airborne-particle abrasion and tribo-chemical silica coating are the pre-treatment methods with more evidence in the literature. Increased adhesion could be expected after physico-chemical conditioning of zirconia. Surface contamination has a negative effect on adhesion. There is no evidence to support a universal adhesion protocol.

Influence of Hot-Etching Surface Treatment on Zirconia/Resin Shear Bond Strength

This study was designed to evaluate the effect of hot-etching surface treatment on the shear bond strength between zirconia ceramics and two commercial resin cements. Ceramic cylinders (120 units; length: 2.5 mm; diameter: 4.7 mm) were randomly divided into 12 groups (n = 10) according to different surface treatments (blank control; airborne-particle-abrasion; hot-etching) and different resin cements (Panavia F2.0; Superbond C and B) and whether or not a thermal cycling fatigue test (5°–55° for 5000 cycles) was performed. Flat enamel surfaces, mounted in acrylic resin, were bonded to the zirconia discs (diameter: 4.7 mm). All specimens were subjected to shear bond strength testing using a universal testing machine with a crosshead speed of 1 mm/min. All data were statistically analyzed using one-way analysis of variance and multiple-comparison least significant difference tests (α = 0.05). Hot-etching treatment produced higher bond strengths than the other treatment with both resin cements. The shear bond strength of all groups significantly decreased after the thermal cycling test; except for the hot-etching group that was cemented with Panavia F2.0 (p < 0.05). Surface treatment of zirconia with hot-etching solution enhanced the surface roughness and bond strength between the zirconia and the resin cement.