Efficacy of low-level laser therapy associated with fluoride therapy for the desensitisation of molar-incisor hypomineralisation: Randomised clinical trial.

BACKGROUND: Molar-incisor hypomineralisation (MIH) is a qualitative enamel defect. AIM: To investigate the low-level laser therapy (LLLT) associated with fluoride varnish for the desensitisation of teeth with MIH. DESIGN: A randomised clinical trial was conducted with 66 children, randomly allocated to the treatments: laser (L); fluoride varnish (FV); and laser + fluoride varnish (L + FV). The participants in the L group underwent two sessions of LLLT (48-hour interval). The FV group received four applications of varnish at one-week intervals. The L + FV underwent two sessions of LLLT and four applications of varnish. Prior to each session and one month after the onset of treatment, tooth sensitivity and its magnitude were evaluated. Intra- and inter-group comparisons were performed (α = 5%). RESULTS: A significant reduction in the mean sensitivity score was found over time in all groups. After the final treatment, a significant difference was found between the L and L + FV groups (P = .011), with a lower score in the L + FV group (0.09), whereas no difference was found between the FV and L + FV groups (P = .095). CONCLUSIONS: Fluoride varnish and the combination of treatments (L + FV) had greater desensitising action on teeth with MIH. Laser therapy demonstrated an immediate desensitising effect, whereas fluoride varnish had a late-onset effect.

Root dentine demineralisation according to frequency of sucrose exposure using high-fluoride dentifrice.

OBJECTIVE: To evaluate root dentine demineralisation, biomass and loosely bound fluoride (CaF2 ) concentration according to different frequencies of sucrose exposure using a high-fluoride dentifrice. BACKGROUND: Although high-fluoride dentifrice has been recommended to arrest root dentine lesions, it is not clear whether it can protect dentine from increased frequencies of sucrose exposure. METHODS: An in situ, crossover, split-mouth study was conducted in 3 phases with 7 days each, in which 10 volunteers used a palatal device containing 4 bovine root dentine slabs (2 on each side) with predetermined initial hardness. Cariogenic challenge consisted in dripping a 20% sucrose solution 0 (control), 2, 4, 6, 8 or 10 times/d in each block. Volunteers used high-fluoride dentifrice (NaF, 5000 µg F/g) 3 times/d. After each phase, final hardness was measured and the percentage of surface hardness loss (%SHL) calculated. Also, biomass and CaF2 concentration on dentine were determined. The data were processed and analysed by ANOVA and Tukey test with significance level set at 5%. The relationship between the variables was analysed by linear regression and Pearson correlation (r). RESULTS: %SHL and biomass were significantly greater than control for sucrose frequencies higher than 6 times/d (P < 0.001), while CaF2 concentration decreased from sucrose frequency higher than 2 times/d (P < 0.001). Regression analysis data showed a significant linear fit between sucrose exposure frequency and the studied variables with a strong correlation (r) for %SHL and CaF2 and moderate for biomass (P < 0.05). CONCLUSION: High-fluoride dentifrice is able to reduce root dentine demineralisation if sucrose consumption is not higher than 6 times/d.

Evaluation of laser fluorescence in monitoring non-cavitated caries lesion progression on smooth surfaces in vitro.

The aim of this study was to evaluate the performance of a pen-type laser fluorescence (LF) device (LFpen: DIAGNOdent pen) to detect and monitor the progression of caries-like lesions on smooth surfaces. Fifty-two bovine enamel blocks were submitted to three different demineralisation cycles for caries-like lesion induction using Streptococcus mutans, Lactobacillus casei and Actinomyces naeslundii. At baseline and after each cycle, the enamel blocks were analysed under Knoop surface micro-hardness (SMH) and an LFpen. One enamel block after each cycle was randomly chosen for Raman spectroscopy analysis. Cross-sectional micro-hardness (CSMH) was performed at different depths (20, 40, 60, 80 and 100 µm) in 26 enamel blocks after the second cycle and 26 enamel blocks after the third cycle. Average values of SMH (± standard deviation (SD)) were 319.3 (± 21.5), 80.5 (± 31.9), 39.8 (± 12.7), and 29.77 (± 10.34) at baseline and after the first, second and third cycles, respectively. Statistical significant difference was found among all periods (p < 0.01). The LFpen values were 4.3 (± 1.5), 7.5 (± 9.4), 7.1 (± 7.1) and 5.10 (± 3.58) at baseline and after the first, second, and third cycles, respectively, among all periods (p < 0.05). The CSMH values after the second and third cycles at 20, 40, 60, 80 and 100 µm were 182.8 (± 69.8), 226.1 (± 79.6), 247.20 (± 69.36), 262.35 (± 66.36) and 268.45 (± 65.49), and for the third cycle were 193.7 (± 73.4), 239.5 (± 81.5), 262.64 (± 82.46), 287.10 (± 78.44) and 284.79 (± 72.63) (n = 24 and 23), respectively. No correlation was observed between the LFpen and SMH values (p > 0.05). One sample of each cycle was characterised through Raman spectroscopy analysis. It can be concluded that LF was effective in detecting the first demineralisation on enamel; however, the method did not show any effect in monitoring lesion progression after three cycles of in vitro demineralisation.

Impacto de la hipomineralización incisivo molar en la experiencia de caries en escolares de 6-12 años en Santiago, Chile / Molar incisor hypomineralisation and its impact on caries experienced by 6-12 year-old schoolchildren from Santiago, Chile

Objetivo: El objetivo de este estudio fue determinar las consecuencias clínicas expresadas en índices COPD y ceod y su relación con la presencia de hipomineralización incisivo molar (HIM) en una población de escolares de 6 a 12 años de la provincia de Santiago. Método: Este estudio de corte transversal fue realizado en 851 escolares de 6 a 12 años de la provincia de Santiago, quienes fueron evaluados por 2 dentistas calibrados. Con consentimiento de los tutores legales, los escolares fueron examinados, y se utilizaron los criterios diagnósticos para HIM de la Academia Europea de Odontopediatría (EAPD). La historia de caries fue determinada con COPD/ceod de acuerdo a los criterios de la OMS. Los datos fueron recolectados en una ficha especialmente diseñada para esto. Los datos fueron analizados con test «t¼ para muestras individuales (considerando p < 0,05). Resultados: Los escolares afectados por HIM tuvieron una media de COPD de 0,91 (±1,21) y una media de ceod de 1,98 (±2,48), el cual fue mayor que el COPD y ceod de escolares sin HIM (0,41 [±0,95] y 1,34 [±2,15] respectivamente). La diferencia entre ambos grupos fue estadísticamente significativa para COPD (p < 0,000) y ceod (p = 0,002). Conclusiones: Escolares de la provincia de Santiago de 6 a 12 años afectados con HIM presentaron mayor COPD/ceod que escolares sin HIM.

Objective. The aim of this study was to determine the clinical consequences, expressed in DMFT and dmft, and their relationship with Molar Incisor Hypomineralisation (MIH) in a population of schoolchildren of 6 to 12 years old in the Santiago Province. Method: A cross-sectional study was conducted on 851 schoolchildren between 6-12 years old from the Santiago Province were examined by two calibrated examiners. With informed consent from their parents, the schoolchildren were examined, and the European Academy of Paediatric Dentistry (EAPD) diagnostic criteria was used for MIH detection. Caries history was assessed with the DMFT/dmft score according to WHO criteria. Data was collected with a form specially designed for this study. Data was analysed using Student's t-test for individual samples and a post-hoc Bonferroni (P < .05). Results: The mean DMFT score in the MIH-affected schoolchildren was 0.91 (±1.21), with a mean dmft score of 1.98 (±2.48), which were greater than the scores in the non-MIH affected schoolchildren (mean DMFT score 0.41 [±0.95] and mean dmft 1.34 [±2.15]). The differences between DMFT and dmft scores in the two groups were statistically significant (P < .000 and P = .002, respectively). Conclusions: Schoolchildren of Santiago Province of 6-12 year old diagnosed with MIH had higher DMFT/dmft scores compared to schoolchildren not affected with MIH.

Do educational methods affect students' ability to remove artificial carious dentine? A randomised controlled trial.

This trial aimed to evaluate the influence of two educational methods on students' ability to remove artificial carious dentine. Traditional lecture and lecture plus a live demonstration of artificial carious tissue removal were compared in a blind two-parallel-group design. Twenty-six students were randomly divided into two groups, and their skills were evaluated according to the following criteria: time spent on the dentine excavation procedure (in min), students' perceived confidence in conducting the procedure (graded assessed on a scale from 0 to 10), and the outcome of artificial carious tissue removal, evaluated by measuring the residual dyed artificial carious dentine layer (in µm). Statistical analyses were carried out using a t-test to compare the students' confidence and time spent on the procedure, and a two-way ANOVA was used to compare residual artificial decayed dentine with educational methods and tooth region (incisal, medium, and cervical thirds) as factors. There were no differences between the methods regarding excavation time (P = 0.898) and students' confidence (P = 0.382). The residual artificial carious dentine results showed that the educational method (P < 0.001) and cavity region (P < 0.001) were statistically significant, as was their interaction (P = 0.040). The lecture plus live demonstration group presented the best results for artificial caries removal. Although there were no differences between the two groups for the cervical region, the best results for the lecture plus live demonstration group was in the other two-thirds of the tooth.