RESUMEN
INTRODUCTION: This study aimed to assess the transfer accuracy of a digital indirect bonding method for lingual brackets using double vacuum-formed trays in vivo. METHODS: Twenty-five patients in need of lingual orthodontic treatment were consecutively recruited. Bracket placement was performed on ideal setups, followed by fabricating indirect bonding trays through vacuum-forming on 3-dimensional printed models. Transfer accuracy was measured at each bracket after superimpositions of postbonding scans and reference data. One-tailed t tests were used to determine whether bracket deviations were within the limit of 0.5 mm and 2° for linear and angular dimensions, respectively. RESULTS: A total of 611 lingual brackets were evaluated. Mean linear transfer errors were 0.06 mm, 0.09 mm, and 0.12 mm, with frequencies of deviations within the 0.5 mm limit of 99.7%, 99.8%, and 98.0% for mesiodistal, buccolingual, and occlusogingival dimensions, respectively. Regarding angular measurements, mean transfer errors were 1.28°, 1.73°, and 2.96°, with frequencies of deviations within the 2° limit of 81.0%, 68.9%, and 51.1% for rotation, tip, and torque, respectively. Mean errors fell within the clinically accepted limits for all linear dimensions and rotation but exceeded the limit for tip and torque. CONCLUSIONS: Lingual bracket indirect bonding using double vacuum-formed trays fabricated on 3-dimensional printed models has high transfer accuracy in the mesiodistal, buccolingual, and occlusogingival dimensions and rotation. However, the transfer of tip and torque is less accurate.
Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Humanos , Vacio , Recubrimiento Dental Adhesivo/métodos , Modelos Dentales , Impresión TridimensionalRESUMEN
Humans have two sets of teeth, deciduous teeth and permanent teeth. When primary teeth fall out, permanent teeth erupt to maintain the chewing function and jaw development. Shedding occurs with increasing level of mobility in primary teeth as a result of root resorption. This report describes an uncommon clinical case that occurred in primary molars with internal resorption and pinkish discoloration. Pink tooth is worrisome for children and parents. Children should have their teeth examined on a regular basis to detect any problems in the process of tooth shedding and eruption.
RESUMEN
BACKGROUND: Fluoride therapy has long been used extensively to prevent dental caries. Fluoride appears in a variety of dental care products such as mouth rinses, dentifrices, gels, etc. HMU Fluorinze is the first mouthwash containing fluoride in Vietnam. AIM: This research was conducted to evaluate the efficacy of HMU Fluorinze mouthwash on remineralizing enamel in laboratory conditions. METHODS: 20 third molar teeth were cleaned and covered with nail polish, except for a 3 x 3 mm square on their buccal surfaces. These teeth underwent two steps: demineralization using Coca-cola and remineralization for 20 daysusing standard calcifying solution (control group) and standard calcifying solution + HMU Fluorinze mouthwash 2 times/day (experimental group). The index measured of enamel structure after demineralization and remineralization was assessed by a DIAGNOdent pen 2190. RESULTS: The indices measured of the control group and experimental group at baseline were 3.65 ± 0.76 and 3.35 ± 0.64 respectively. After demineralization the control group measured 21.78 ± 4.48 and the experimental group, 20.25 ± 2.26. Following remineralization, the control group scores were 6.30 ± 1.03 and the experimental group, 3.90 ± 1.24, demonstrating statistical significance (p < 0.01) between the two groups. After 20 days, the results for the experimental group did not differ from the original results (p = 0.272), in contrast with the control group (p < 0.01). CONCLUSION: Results show that HMU Fluorinze mouthwash is better at remineralizing than standard calcifying solution.
