Giomers in dentistry – at the boundary between dental composites and glass-ionomers

Abstract

Introduction. From the variety of direct restorative dental materials, composite resins are considered as having the most esthetic and functional properties. The conservative preparation, esthetic results, good mechanical qualities and surface finishing properties of dental composites, combined with the protective properties of fluoride from glass-ionomers, led to a new generation of dental materials: the giomers.
 Objective. The purpose is to review the available literature about the giomers, regarding the chemical composition, handling properties and esthetics, adhesion and microleakage, fluoride releasing and protection offered, clinical indications.
 Method. The search was carried out using ScienceDirect and PubMed databases with the following keywords: giomer, esthetic properties giomers and fluoride releasing giomers. A total of 232 articles were initially selected, with the following inclusion criteria: full text articles, written in English, with topics on the properties and the clinical implications of giomers. Papers presented as abstract were not included. In the next step, review articles, duplicates, and articles in other languages were removed; as a result, a total of 44 sources published between 2004 and 2017 were selected.
 Results. The selected articles referred to the following aspects about the giomers: chemical composition (8 articles), adhesion and microleakage (10 articles), fluoride releasing and pulp protection (15 articles), clinical indications (6 articles), effects of additional treatments and dietary habits (11 articles).

Optical properties and masking capacity of flowable giomers

“…The main categories of materials for direct esthetic restorations are composite resins, glass-ionomers, and materials that, through their composition, properties and indications, are at the intersection of these two groups: resin-modified glass-ionomers, compomers, giomers [7][8][9][10][11].…”

“…Giomers were developed with the desire to combine the esthetics of composites with the antibacterial protection of glass-ionomers and they are available in a wide range of colors classified by the VITA Classical shade guide system in the four hue groups (A, B, C and D, each with subgroups of saturations), with some variations depending on the type of material. Giomers have shown ideal properties for restoring cervical carious and non-carious lesions, one of the main challenges of direct restorative dentistry due to the quality of adhesion at the cervical level [11,[15][16][17]. Moreover, for these lesions, flowable materials would be indicated, as they have higher flexibility and are less likely to be displaced from high-stress areas [18].…”

“…Due to fluoride release, glass-ionomers provide protection from carious lesions and bond chemically to the tooth structure [ 11 , 13 , 14 ].…”

Bioactive Materials Opportunity and Challenges in Dentistry

“…Giomers, represent the hybridization of the properties of glass ionomers and composite resins: the release of fluoride and the recharge of glass ionomers and the aesthetics, physical properties and handling of composite resins. Creating fluorine reservoirs releases and recharges fluorine efficiently, although not as well as glass ionomers [26].…”

Water Sorption and Solubility of Flowable Giomers

“…Giomers are hybrid materials, having a resin matrix and pre-reacted glass filler (PRG) and controlled fluoride releasing properties. They comprise the easy handling and esthetic properties of composite resin materials and the carious protection thru fluoride release offered by glass-ionomers [ 1 ]. The PRG filler is the result of an acid–base chemical reaction between a fluoroalumino-silicate glass and polyalkenoic acid (PAA) in the presence of water, leading to a glass-ionomer in a stable form (“wet silicon hydrogel”) [ 2 ].…”