Franciny Querobim Ionta

In vitro assessment of artificial saliva formulations on initial enamel erosion remineralization

OBJECTIVES Various formulations of artificial saliva are present in the literature and little guidance is available on the standardization of type of saliva for use in in vitro protocols for erosive studies. The aim of this study was to evaluate the remineralizing capacity of different formulations of artificial saliva on initial enamel erosive lesion. METHODS Bovine enamel blocks were subjected to short-term acidic exposure by immersion in citric acid 0.05 M (pH 2.5) for 15s, resulting in surface softening without tissue loss. Then 90 selected eroded enamel blocks were randomly and equally divided into 6 groups according to saliva formulation (n=15): Saliva 1 (contain mucin); Saliva 2 (Saliva 1 without mucin); Saliva 3; Saliva 4; Saliva 5 (contain sodium carboxymethyl cellulose) and control (C) (deionized water). After demineralization enamel blocks were subjected to remineralization by immersion in the salivas formulations for 2h. Enamel remineralization was measured by superficial hardness test (% superficial hardness change). The data were tested using ANOVA and Tukeys test (p<0.05). RESULTS All the tested formulations of artificial saliva resulted in significantly higher enamel remineralization compared to control (p<0.001). Saliva 3 showed higher percentage of enamel remineralization than Saliva 5 (p<0.05). CONCLUSIONS Besides the variety of artificial saliva for erosion in vitro protocols, all the formulations tested were able to partially remineralize initial erosive lesions.

Penetration of resin-based materials into initial erosion lesion: A confocal microscopic study.

The application of resin‐based materials is an alternative of treatment for eroded lesions. Nevertheless, there are no studies about the penetration of these materials into eroded lesion, which might affect its adhesion. Therefore, this study evaluated the penetration of four resin‐based materials, with and without enamel etching. By using an in vitro protocol, types of treatment were studied at five levels (AdheSE®, Tetric N‐Bond®, Single Bond 2®, Helioseal Clear®, Icon®) and types of enamel etching in two levels (with and without). Materials were stained with 0.02 mg/mL ethanolic solution of tetramethylrhodamine isothiocyanate. Bovine enamel samples (4 × 4 mm) were immersed in 0.01 M HCl, pH 2.3, for 30 seconds to produce initial eroded lesions. Afterward, the materials were applied on half of sample enamel surface following the manufacturers instructions. On the other half of sample, the materials were applied without etching the enamel. Materials penetration into the enamel was assessed by Confocal Laser Scanning Microscopy on reflection and fluorescence modes. The penetration depth (PD) was measured using ImageJ software. Data were analyzed by two‐way ANOVA and Tukey test (P < 0.05). Regardless of the material, etched enamel resulted in higher PD than non‐etched (P < 0.05). Icon® showed the highest PD in enamel followed by Helioseal Clear® (P < 0.05), with significant difference between them (P < 0.05) and no difference was found among AdheSE®, Tetric N‐Bond®, and Single Bond 2® (P > 0.05). It can be concluded that prior enamel etching increased the materials penetration into eroded enamel and the Icon®—infiltrant presented highest penetration. Microsc. Res. Tech. 79:72–80, 2016.

The Effect of Mucin in Artificial Saliva on Erosive Rehardening and Demineralization

The effect of mucin in artificial saliva on rehardening (RE-experiment) and inhibition (DE-experiment) of erosion was evaluated. The treatment groups were: artificial saliva with mucin, artificial saliva without mucin, human saliva, and water. For the RE-experiment, after immersion of enamel blocks in citric acid (4 min), hardness was measured and blocks were subjected to treatment for 2 h. For the DE-experiment, sound blocks were subjected to treatment for 2 h and immersed in citric acid (4 min). Percentages of hardness recovery (RE) and loss (DE) were analyzed (ANOVA/Tukeys test). The salivas promoted similar rehardening, but only the saliva with mucin was similar to human saliva with regard to enamel protection against erosion.

Impact of a simplified in situ protocol on enamel loss after erosive challenge

This study investigated the effect of the period of use and location of intraoral appliances on enamel surface loss. This randomized, single blind in situ study was conducted in 2 crossover phases based on the period of use, in which maxillary and mandibular appliances were simultaneously worn. Bovine enamel blocks (n = 120) were randomly divided among the studied groups by surface hardness. In each phase, fifteen volunteers used one maxillary appliance and two mandibular appliances for 5 days. Erosive challenge was performed 4X/day by immersion in 0.01 M HCL for 2 minutes. In the continuous phase, the intraoral appliances were worn for 20 hours. In the intermittent phase the appliances were worn for 8 hours and 30 minutes. Enamel loss was determined profilometrically. The discomfort of use of the appliances were evaluated in a questionnaire. Data were analyzed by two-way ANOVA/Tukey’s test and chi-square test (p<0.05). The maxillary appliance promoted higher enamel loss compared to the mandibular one (p<0.001). Intermittent use of appliances resulted in similar enamel loss to the continuous one (p = 0.686). All volunteers preferred to use the maxillary appliance in an intermittent regimen. The intermittent use of maxillary appliance is a simplified reliable protocol appropriated for in situ erosion studies in enamel.

Effect of vegetable oils applied over acquired enamel pellicle on initial erosion

Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 – 5% and pure palm oil, respectively; GC5 and GC100 – 5% and pure coconut oil; GSa5 and GSa100 – 5% and pure safflower oil; GSu5 and GSu100 – 5% and pure sunflower oil; GO5 and GO100 – 5% and pure olive oil; CON− – Deionized Water (negative control) and CON+ – Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey’s test (p<0.05). Results Enamel blocks of GP100 presented similar hardness loss to GSu100 (p>0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.

Effect of palm oil alone or associated to stannous solution on enamel erosive-abrasive wear: A randomized in situ/ex vivo study

OBJECTIVE Palm oil has demonstrated preventive potential against initial erosive demineralization in vitro. This in situ study evaluated the effect of palm oil alone or associated with stannous-containing (Sn) solution on preventing enamel loss from an erosive/abrasive challenge. DESIGN This single-blind, randomized, crossover in situ/ex vivo study was developed in four phases (one per group of five days) with sixteen volunteers. Enamel blocks (n = 256) were allocated to groups according to the treatment: Palm oil; Palm oil plus Sn solution; Sn solution - positive control; and Deionized water - negative control. Half of the enamel blocks of each group was subjected to erosion and the other half to erosion + abrasion. The daily ex vivo protocol consisted of four citric acid immersions (2 min). Before the first and third acid exposure, the blocks were treated with the test solutions (1 drop/block) for 1 min followed by acid immersion and abrasive challenge (toothpaste was applied on all blocks and half were brushed for 15 s/block). Enamel loss was quantified profilometrically and data were analyzed by two-way ANOVA and Tukeys test (p < 0.05). RESULTS A significant difference was found for type of treatment (p < 0.001); wear condition (p = 0.38) and the treatment x condition interaction (p = 0.33) was non-significant. Palm oil associated or not to Sn solution significantly reduced enamel wear in comparison with the negative control but did not differ from the positive control (p > 0.05). CONCLUSIONS Palm oil was able to prevent enamel loss under erosive and erosive + abrasive challenges in a similar extend to stannous-containing commercial solution.

Delayed Treatment of Traumatized Primary Teeth with Distinct Pulp Response: Follow-Up until Permanent Successors Eruption

Complicated crown fracture and crown-root fracture with pulp involvement expose dental pulp to the oral environment. The pulp outcome is often unpredictable because the patient and injury which are related to variables can influence the treatment of choice and the prognosis of the case. This report presents the case of a 4-year-old boy with complicated crown fracture with pulp polyp in the primary right maxillary central incisor (51) and crown-root fracture with pulp involvement in the primary left maxillary central incisor (61), which was treated only 3 months after the tooth injuries. The treatment of choice was extraction of tooth (61) due to a periapical lesion with disruption of the dental follicle of the permanent successor and pulpotomy (MTA) of the tooth (51), because the pulp presented signs of vitality. At the follow-up visits, no clinical, symptomalogical, and radiographic changes were observed until the primary tooths exfoliation. However, at 3-year follow-up, the permanent successors showed hypocalcification and the position of the permanent right maxillary central incisors (11) was altered. Besides the conservative and adequate delayed treatment, the sequelae on the permanent successors could not be avoided.

Impact of Saliva and Intraoral Appliance on Erosion Lesions Rehardening Ability - A Pilot Study

Objective: To evaluate the ability of different periods of salivary exposure and two different removable appliances to rehardening initial erosive lesions. Material and Methods: This randomized, single blind in situ study was conducted with 2 crossover phases. The factors under study were: period of salivary exposure (15 minutes, 30 minutes, 1 hour and 2 hours) and type of oral appliance (maxillary or mandibular). Two hundred enamel blocks were selected by initial surface hardness (SHi). Enamel blocks were demineralized in vitro (0.05M citric acid; pH2.5 for 15 seconds), surface hardness (SHd) was remeasured and 160 blocks were selected and randomized among groups. Thus, there were 2 blocks per period of salivary exposure in each type of oral appliance for each one of the 10 volunteers. In each phase, one of the removable appliances was tested. The response variable was percentage of surface hardness recovery (%SHR=[(SHf-SHd)/SHi)]x100). Two-way ANOVA and Tukey’s post hoc test were applied adopting 5% of significance. Results: No difference was found among oral appliances on enamel rehardening (p>0.01). Salivary exposure of 2 hours promoted similar enamel rehardening when compared to 1 hour (p>0.05), which showed similar rehardening to 30 min. All mentioned period of salivary exposure promoted superior rehardening than 15 min (p>0.01). Conclusion: The salivary time exposure between erosive attacks might be 2 hours to achieve a feasible maximum rehardening. In addition, both maxillary and the mandibular appliance have presented a similar rehardening ability.