Dental erosive wear and salivary flow rate in physically active young adults

Background Little attention has been directed towards identifying the relationship between physical exercise, dental erosive wear and salivary secretion. The study aimed i) to describe the prevalence and severity of dental erosive wear among a group of physically active young adults, ii) to describe the patterns of dietary consumption and lifestyle among these individuals and iii) to study possible effect of exercise on salivary flow rate. Methods Young members (age range 18-32 years) of a fitness-centre were invited to participate in the study. Inclusion criteria were healthy young adults training hard at least twice a week. A non-exercising comparison group was selected from an ongoing study among 18-year-olds. Two hundred and twenty participants accepted an intraoral examination and completed a questionnaire. Seventy of the exercising participants provided saliva samples. The examination was performed at the fitness-centre or at a dental clinic (comparison group), using tested erosive wear system (VEDE). Saliva sampling (unstimulated and stimulated) was performed before and after exercise. Occlusal surfaces of the first molars in both jaws and the labial and palatal surfaces of the upper incisors and canines were selected as index teeth. Results Dental erosive wear was registered in 64% of the exercising participants, more often in the older age group, and in 20% of the comparison group. Enamel lesions were most observed in the upper central incisors (33%); dentine lesions in lower first molar (27%). One fourth of the participants had erosive wear into dentine, significantly more in males than in females (p = 0.047). More participants with erosive wear had decreased salivary flow during exercise compared with the non-erosion group (p < 0.01). The stimulated salivary flow rate was in the lower rage (≤ 1 ml/min) among more than one third of the participants, and more erosive lesions were registered than in subjects with higher flow rates (p < 0.01). Conclusion The study showed that a high proportion of physically active young adults have erosive lesions and indicate that hard exercise and decreased stimulated salivary flow rate may be associated with such wear

Erosive cola-based drinks affect the bonding to enamel surface: an in vitro study

Objective: This study aimed to assess the impact of in vitro erosion provoked by different cola-based drinks (Coke types), associated or not with toothbrushing, to bonding to enamel. Material and methods: Forty-six bovine enamel specimens were prepared and randomly assigned into seven groups (N=8): C- Control (neither eroded nor abraded), ERO-RC: 3x/1-minute immersion in Regular Coke (RC), ERO-LC: 3x/1-minute immersion in Light Coke (LC), ERO-ZC: 3x/1-minute immersion in Zero Coke (ZC) and three other eroded groups, subsequently abraded for 1-minute toothbrushing (EROAB-RC, EROAB-LC and EROAB-ZC, respectively). After challenges, they were stored overnight in artificial saliva for a total of 24 hours and restored with Adper Single Bond 2/Filtek Z350. Buildup coronal surfaces were cut in 1 mm2 -specimens and subjected to a microtensile test. Data were statistically analyzed by two-way ANOVA/Bonferroni tests (α=0.05). Failure modes were assessed by optical microscopy (X40). The Interface of the restorations were observed using Confocal Laser Scanning Microscopy (CLSM). Results: All tested cola-based drinks significantly reduced the bond strength, which was also observed in the analyses of interfaces. Toothbrushing did not have any impact on the bond strength. CLSM showed that except for Zero Coke, all eroded specimens resulted in irregular hybrid layer formation. Conclusions: All cola-based drinks reduced the bond strength. Different patterns of hybrid layers were obtained revealing their impact, except for ZC

Flexural strength of fluorapatite-leucite and fuorapatite porcelains exposed to erosive agents in cyclic immersion

OBJECTIVE: The aim of this study was to evaluate the fexural strength of two porcelain materials (IPS d.SIGN and IPS e.max Ceram) exposed to erosive agents. MATERIAL AND METHODS: One hundred and twenty bar-shaped specimens were made from each of fuorapatite-leucite porcelain (IPS d.SIGN) and fuorapatite porcelain (IPS e.max Ceram) and divided into 8 groups of 15 specimens each. Six groups were alternately immersed in the following storage agents for 30 min: deionized water (control), citrate buffer solution, pineapple juice, green mango juice, cola soft drink and 4% acetic acid. Then, they were immersed for 5 min in deionized water at 37ºC. Seven cycles were completed, totalizing 245 min. A 7th group was continuously immersed in 4% acetic acid at 80ºC for 16 h. The final, 8th, group was stored dry at 37ºC for 245 min. Three-point bending tests were performed in a universal testing machine. The data were analyzed statistically by 2-way ANOVA, Tukey's HSD test and t-test at signifcance level of 0.05. RESULTS: The fexural strengths of all groups of each porcelain after exposure to erosive agents in cyclic immersion did not differ signifcantly (p>0.05). For both types of porcelain, dry storage at 37ºC yielded the highest fexural strength, though without signifcant difference from the other groups (p>0.05). The fexural strengths of all groups of fuorapatite porcelains were signifcantly higher (p<0.05) than those of the fuorapatite-leucite porcelains. CONCLUSIONS: This study demonstrated that the erosive agents evaluated did not affect the fexural strength of the tested dental porcelains