Dry mouth diagnosis and saliva substitutes—A review from a textural perspective

Abstract

The aim of this review is to assess the objective and subjective diagnosis, as well as symptomatic topical treatment of dry mouth conditions with a clear focus on textural perspective. We critically examine both the current practices as well as outline emerging possibilities in dry mouth diagnosis and treatment, including a patent scan for saliva substitutes. For diagnosis, salivary flow rates and patient‐completed questionnaires have proven to be useful tools in clinical practice. To date, objective measurements of changes in mechanical properties of saliva via rheological, adsorption, and tribological measurements and biochemical properties of saliva such as assessing protein, mucins (MUC5B) are seldom incorporated into clinical diagnostics; these robust diagnostic tools have been largely restricted to application in non‐clinical settings. As for symptomatic treatments of dry mouth, four key agents including lubricating, thickening, adhesive, and moisturizing agents have been identified covering the overall landscape of commercial saliva substitutes. Although thickening agents such as modified celluloses, polysaccharide gum, polyethylene glycol, and so forth are most commonly employed saliva substitutes, they offer short‐lived relief from dry mouth and generally do not provide boundary lubrication properties of real human saliva. Innovative technologies such as self‐assembly, emulsion, liposomes, and microgels are emerging as novel saliva substitutes hold promise for alternative approaches for efficient moistening and lubrication of the oral mucosa. Their adoption into clinical practice will depend on their efficacies, duration of relief, and ease of application by the practitioners and patient compliance.

A Review on Xerostomia and Its Various Management Strategies: The Role of Advanced Polymeric Materials in the Treatment Approaches

“…The symptomatic relief or control of oral dryness includes hydration (frequent sipping of water), discontinuation or reduction in xerogenic medications, and elimination of common dry mouth offenders, such as tobacco and alcohol [ 76 ]. Moreover, artificial salivary substitutes (i.e., commercial products containing specific ingredients, whose properties resemble those of the natural saliva) are frequently used as symptomatic treatments for patients with decreased salivary flow rate [ 77 , 78 ]. In fact, they act as oral lubricants that maintain the lubrication of the mucosa and, hence, relieve the sensation of dryness, without stimulating the salivary flow.…”

“…In case there is residual functional salivary tissue, one of the alternatives for xerostomia and hyposalivation is the use of salivary stimulants [ 100 , 105 ]. Generally, salivary stimulation can be divided into acid-, pharmaceutically-, and mechanically- driven [ 77 ].…”

A Review on the Role of Pilocarpine on the Management of Xerostomia and the Importance of the Topical Administration Systems Development

“…The available treatments for xerostomia include, among others, salivary substitutes, selected in case of salivary glands' complete damage, or salivary stimulants, chosen when salivary gland retain, at least partially, their functionality. Salivary stimulants encompass chewing gums (mechanical stimulation), malic and ascorbic acid (acid stimulation is generally avoided, despite its effectiveness, due to its potential demineralizing effect on tooth enamel [18]) and parasympathomimetic drugs (pharmaceutical stimulation) [19][20][21][22]. Various medications have been suggested as systemic sialagogues, such as pilocarpine, cevimeline and bethanechol, since they are capable of inducing the secretion of natural saliva from the undamaged part of the salivary glands through their action on muscarinic receptors.…”

Stable oral lubrication enhancer obtained from thiolated polyethylene glycol and mucin

“…Polyethylene glycol (PEG), a non-toxic and biocompatible synthetic material [14], is usually used as a mucoadhesive material in commercial salivary substitutes, which can self-assemble an artificial salivary pellicle [15]. It has been proven that Oasis (PEG 60 hydrogenated and castor oil-based) saliva substitutes presented similar adsorption behavior as human saliva [16].…”