MATERIALS AND METHODS: Sound extracted human molars were randomly divided into: manufacturer's instructions (MI), manual blend 2 mm (MB2), and manual blend 4 mm (MB4). Occlusal enamel was removed and flattened, dentin surfaces were bonded by Prime & Bond universal (Dentsply and Optibond FL, Kerr). For the MI group, adhesives were applied following the manufacturer's instructions then light-cured. For MB groups, SDR flow+ bulk-fill flowable composite resin was applied in 2- or 4-mm increment then manually rubbed by a micro brush for 15 s with uncured dentine bonding agents and the mixture was light-cured. Composite buildup was fabricated incrementally using Ceram.X One, Dentsply nanohybrid composite resin restorative material. After 24-h water storage, the teeth were sectioned to obtain beams of about 0.8 mm2 for 24-h and thermocycled micro-tensile bond strength at 0.5 mm/min crosshead speed. Degree of conversion was evaluated with micro-Raman spectroscopy. Contraction gaps at 24 h after polymerization were evaluated and atomic force microscopy (AFM) nano-indentation processes were undertaken for measuring the hardness across the interface. Depth of resin penetration was studied using a scanning electron microscope (SEM). Bond strength data was expressed using two-way ANOVA followed by Tukey's test. Nanoindentation hardness was separately analyzed using one-way ANOVA.
RESULTS: Factors "storage F = 6.3" and "application F = 30.11" significantly affected the bond strength to dentine. For Optibond FL, no significant difference in nanoleakage was found in MI/MB4 groups between baseline and aged specimens; significant difference in nanoleakage score was observed in MB2 groups. Confocal microscopy analysis showed MB2 Optibond FL and Prime & Bond universal specimens diffusing within the dentine. Contraction gap was significantly reduced in MB2 specimens in both adhesive systems. Degree of conversion (DC) of the MB2 specimens were numerically more compared to MS1 in both adhesive systems.
CONCLUSION: Present study suggests that the new co-blend technique might have a positive effect on bond strengths of etch-and-rinse adhesives to dentine.
Objectives: The main aim of the study was to determine and compare the erosive potential of different fruit juices in frozen/unfrozen forms on primary teeth by studying the calcium dissolution.
Materials and methods: pH of four different juices (pure) - apple, orange, citrus limetta (musumbi) and grapes were determined using a digital pH meter. The titratable acidity of these in frozen and unfrozen forms were determined by adding 0.2 ml of 1M NaOH to these to raise to pH=5.5(critical pH) and pH =7(neutral pH). Forty eight caries free deciduous anterior teeth specimens were prepared to study the calcium dissolution by atomic absorption spectrophotometer. The results were analysed for statistical significance using One-way Repeated Measures ANOVA and pair wise multiple comparison with Bonferroni correction.
Results: Total titratable acidity and calcium dissolution were found to be significantly more in the initial thawed fruit juices.
Conclusion: Frozen fruit juices had more buffering capacity and erosive potential than unfrozen forms. The study concluded that sucking on frozen fruit juices is more damaging to teeth than unfrozen forms because more of erosion is expected to occur in a frozen state.
MATERIALS AND METHODS: A total of 370 orthodontic records including their pre-treatment orthopantomographs (OPG) and study models of orthodontic patients in permanent dentition who attended dental clinic were assessed for impaction, hypodontia, supernumerary, supraocclusion, infraocclusion, and any other anomalies excluding the third molars. The association of anomalies with gender status and racial status was analyzed using Pearson's Chi-square test. A P value of <0.05 is considered as significant. The confidence interval at 95% (CI) was set.
RESULTS: Among the 370 subjects, 105 (28.4%) presented with at least one anomaly. Eighty-five (23%) demonstrated a single anomaly and 20 (5.4%) with more than one anomaly. The most prevalent anomaly was impaction (14.32%), followed by hypodontia (7.03%). The less common anomalies were microdontia (1.08%), dilacerations (0.27%), and generalised enamel hypoplasia (0.27%). Maxillary right lateral incisors and canines were the most common affected teeth and these are located on the maxillary right quadrant. It was evident that dental anomalies were statistically dependant on race (P = 0.025), but independent of gender. The most common treatment planned for these patients was fixed appliance.
CONCLUSIONS: Impaction was predominant among 28.4% subjects observed with anomaly and most patients with anomaly are treated with fixed appliances (49%).
CLINICAL RELEVANCE: These anomalies play a great role in occlusion and alignment in treatment planning and relapse for orthodontic treatment.
METHODS: Participants were 7- to 16-year-old children referred to a UK Dental Hospital for management of incisor opacities. Prior to treatment (To), participants completed validated questionnaires to assess OHRQoL and overall health status (C-OHIP-SF19), and self-concept (Harter's Self-Perception Profile for Children [SPPC]). Interventions for MIH included microabrasion, resin infiltration, tooth whitening or composite resin restoration. Children were reviewed after six months (T1) when they re-completed the C-OHIP-SF19 and SPPC questionnaires. The relationships of predictors with improvement of children's OHRQoL (T1-To) and children's overall health status at T1 were assessed using linear and ordinal logistic regression respectively, guided by the Wilson and Cleary's theoretical model.
RESULTS: Of 103 participants, 86 were reviewed at T1 (83.5 % completion rate). Their mean age was 11-years (range = 7-16) and 60 % were female. Total and domain OHRQoL scores significantly increased (improved OHRQoL) following MIH treatment. There was a significant positive change in SPPC physical appearance subscale score between To and T1. A higher number of anterior teeth requiring aesthetic treatment were associated with poor improvement of socio-emotional wellbeing at T1 (Coef =-0.43). Higher self-concept at To was associated with greater improvement of socio-emotional wellbeing at T1 (ß = 3.44). Greater orthodontic treatment need (i.e. higher IOTN-AC score) at T0 was linked to worse overall oral health at T1 (OR = 0.43).
CONCLUSIONS: Psychosocial factors and dental clinical characteristics were associated with change in children's OHRQoL following minimal interventions for incisor opacities.
CLINICAL SIGNIFICANCE: MIH is a common condition and clinicians should be aware of the negative impacts some children experience, particularly those with multiple anterior opacities, poor tooth alignment and low self-concept. However, simple, minimally invasive treatments can provide good clinical and psychosocial outcomes and should be offered to children reporting negative effects.