In-office tooth bleaching with chitosan-enriched hydrogen peroxide gels: in vitro results

• Published in: Clinical oral investigations Vol. 26; no. 1; pp. 471 - 479
• Main Authors: Pini, Núbia Inocencya Pavesi, Piccelli, Marcella Ricomini, Vieira-Junior, Waldemir Franscisco, Ferraz, Laura Nobre, Aguiar, Flávio Henrique Baggio, Lima, Débora Alves Nunes Leite
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2022; Springer Nature B.V
• Subjects: Animals; Bleaching; Calcium; Cattle; Chitosan; Dental enamel; Dentin; Dentistry; Gels; Generalized linear models; Hydrogen Peroxide; Kruskal-Wallis test; Medicine; Original Article; Saliva; Scanning electron microscopy; Teeth; Tooth Bleaching; Tooth Bleaching Agents; Tooth bleaching; Hydrogen peroxide; Chitosan; Enamel
• ISSN: 1432-6981; 1436-3771
• DOI: 10.1007/s00784-021-04021-4

Objective
This study aimed to evaluate the effects of adding chitosan to 35% hydrogen peroxide gels (for in-office bleaching), with or without calcium gluconate, on tooth properties and bleaching efficacy.
Methods
Bovine enamel/dentin specimens (4 × 4 × 2.5 mm) were randomly allocated into groups (
n
 = 10): negative control (unbleached), bleaching with 35% hydrogen peroxide gel (35% HP, commercial gel); 35% HP with 2% chitosan (% wt) (35% HP + chitosan), 35% HP and calcium (35% HP + Ca, commercial gel), and 35% HP + Ca + 2% chitosan. Variation of surface profile (ΔRa) and color analyses (ΔL*, Δa*, Δb*, ΔE*
ab
, ΔE
00
, and ΔWID) were performed comparing specimens at baseline (initial) and 24 h after of storage in artificial saliva (final). Surface microhardness (KHN) values and scanning electron microscopy (SEM) images were obtained on conclusion. The data were analyzed by ANOVA and Tukey’s tests (KHN), generalized linear models (ΔL*, ΔE
ab
, ΔE
00
, ΔWID, ΔRa), and Kruskal–Wallis and Dunn tests (Δa*, Δb*) (α = 0.05).
Results
Considering ΔL*, Δa*, Δb*, ΔE*
ab
, ΔE
00
, and ΔWID values, the bleached groups differed from negative control. For ΔRa, chitosan-based groups showed lower variation in surface roughness compared to 35% HP, without significant difference from negative control. For KHN, chitosan groups did not differ from negative control (unbleached control = chitosan groups > 35% HP + Ca > 35% HP). For SEM, slight surface changes were observed in all bleached groups, but the intensity varied according to gel used (35% HP > gels with Ca > gels with chitosan).
Conclusion
Chitosan-enriched hydrogen peroxide gels can reduce negative impacts on tooth properties without affecting bleaching efficacy.
Clinical relevance
Although commercial gels containing remineralizing agents such as calcium reduce the negative effects on the properties of teeth, the addition of chitosan appears to be a promising approach to preservation of dental properties without interfering in bleaching efficacy.