Aims: This study aims to evaluate and compare the bond strength and load deflection rate (LDR) of three different fixed retainer wires.
Materials and Methods: The wires were divided into three Groups: A - three-stranded twisted ligature wire, B - Bond-A-Braid (Reliance Orthodontics), and C - three-stranded twisted lingual retainer wire (3M Unitek). Twenty models were prepared for each group with a passive 15 mm long lingual retainer wire bonded to two lower incisors. An occlusogingival force was applied to the wire until it debonded. For LDR, three-point bending test was done at 0.5 mm deflection. These forces were measured using a Universal Instron Testing Machine.
Statistical Analysis: Mean bond strength/LDR and pairwise comparisons were analyzed with one-way ANOVA and Tukey's honest significant differencepost hoctest, respectively.
Results: Group C exhibited the highest mean bond strength and LDR of 101.17N and 1.84N, respectively. The intergroup comparisons were all statistically significant.
Conclusion: Compared to the other two wire types, Group C might be better retained on the teeth due to its higher bond strength. With its relatively higher LDR value, it may resist deformation from occlusal forces, thereby reducing inadvertent tooth movement and yet remain flexible enough to allow physiologic tooth movements.
MATERIALS AND METHODS: A cross-sectional survey was performed. Primary maxillary and mandibular anterior teeth of 1,800 children aged between 2 years and 6 years, who attended 20 pre-schools in National Capital Region Delhi, India, were examined by a single examiner, and a questionnaire was filled in person by the parent/guardian. Andreasen's classification was used to classify the traumatic injuries. The Chi-square test was used to statistically analyze the variation in traumatic dental injuries (TDIs) with age and gender. Multiple logistic regression was used to determine the influence of independent variables on the occurrence of TDIs.
RESULTS: The prevalence of TDIs was 17%. Significant and highly significant differences were found between boys and girls for cause and location of trauma (p < 0.05) and tooth type involved (p < 0.001) with boys being more prone to such injuries. The commonest cause of injury was due to falls and the location was playground. The teeth most commonly affected were the maxillary central incisors (36.9%) followed by maxillary lateral incisors (3.3%), and the least affected were the maxillary and mandibular canines (0.3%).
CONCLUSION: The prevalence of traumatic injuries to the anterior teeth in 2- to 6-year-old children in National Capital Region of Delhi, India, was 17%. There is a need to run educational programs to increase parents' awareness of the risks of dental trauma and emphasize preventive measures.
CLINICAL SIGNIFICANCE: Parents should be made aware of the widespread prevalence, risk factors, and consequences of trauma to primary dentition, so that they can seek appropriate care timely. The time elapsed between injury and dental care is of utmost importance.
MATERIALS AND METHODS: The sample consisted of 63 dentate subjects (21 Malays, 21 Chinese, and 21 Indians) who were chosen based on the inclusion criteria. Two models were made using irreversible hydrocolloid impressions, and an average of the value was obtained. Lingual frenum was recorded in function. Casts were fabricated with dental stone. AALF was marked and the vertical distance was measured using a caliper.
RESULTS: In Malays, the mean and standard deviation of the vertical distance were 14.2 ± 0.9 mm, with a range of 12.3-16.0 mm; in Chinese were 14.4 ± 0.9 mm, with a range of 12.0-16.9 mm; and in Indians were 15.1 ± 1.0 mm, with a range of 13.0-17.2 mm. The difference among the three races regarding the distance between AALF and the incisal edge of mandibular central incisors was statistically significant (P < 0.05). Among the three races, Malays and Indians have the greatest mean difference.
CONCLUSION: According to the results of the current study, the distance between AALF and the incisal edge of mandibular central incisors might be a proper criterion for the initial adjustment of occlusal rims. The values obtained from three different races were significantly different from one another, hence a different range of values was used to establish occlusal height for different races.
BACKGROUND: Molar-Incisor Hypomineralization (MIH) prevalence in paediatric patients has been widely studied. However, most of the available studies have utilised criteria that did not offer consistent diagnostic and calibration tools, which resulted in incomparable results.
METHODS: Cross-sectional study. One hundred sixty-two school children aged 7-9 years in the city of Fujairah, UAE have been randomly selected and orally examined for the presence of MIH lesions. This was conducted following Ghanim et al. [2015] guidelines and after calibrating examiners following Ghanim et al. [2017] training manual.
CONCLUSION: MIH prevalence was high in the city of Fujairah, UAE. More studies utilising the standardised criteria are required for valid comparisons. Further research on the aetiology of MIH is also needed.