Impact of passive self-ligation and conventional elastic ligation on orthodontic force in the simulation of a mandibular lateral incisor linguoversion

New generation of orthodontic devices and materials with bioactive capacities to improve enamel demineralization

OBJECTIVE

The article reviewed novel orthodontic devices and materials with bioactive capacities in recent years and elaborated on their properties, aiming to provide guidance and reference for future scientific research and clinical applications.

DATA, SOURCES AND STUDY SELECTION

Researches on remineralization, protein repellent, antimicrobial activity and multifunctional novel bioactive orthodontic devices and materials were included. The search of articles was carried out in Web of Science, PubMed, Medline and Scopus.

CONCLUSIONS

The new generation of orthodontic devices and materials with bioactive capacities has broad application prospects. However, most of the current studies are limited to in vitro studies and cannot explore the true effects of various bioactive devices and materials applied in oral environments. More research, especially in vivo researches, is needed to assist in clinical application.

CLINICAL SIGNIFICANCE

Enamel demineralization (ED) is a common complication in orthodontic treatments. Prolonged ED can lead to dental caries, impacting both the aesthetics and health of teeth. It is of great significance to develop antibacterial orthodontic devices and materials that can inhibit bacterial accumulation and prevent ED. However, materials with only preventive effect may fall short of addressing actual needs. Hence, the development of novel bioactive orthodontic materials with remineralizing abilities is imperative. The article reviewed the recent advancements in bioactive orthodontic devices and materials, offering guidance and serving as a reference for future scientific research and clinical applications.

Impact of the prefabricated forms of NiTi archwires on orthodontic forces delivered to the mandibular dental arch

BACKGROUND

Although preformed archwires with a variety of arch forms are currently commercially available, the effects of variation in the shape of these archwires on the orthodontic force at each tooth are not well understood. Therefore, we evaluated the forces delivered by various types of commercially available preformed nickel-titanium alloy (NiTi) archwires in a simulated mandibular dental arch.

METHODS

Sixty-three types of 0.019 × 0.025-inch preformed NiTi archwires from 15 manufactures were selected for analysis. The intercanine width (ICW) and intermolar width (IMW) of each archwire were measured at the mean canine and first molar depths of 30 untreated subjects with normal occlusions. Each archwire was placed in a multi-sensor measurement system simulating the mandibular dental arch of subjects with normal occlusions, and orthodontic forces in the facial-lingual direction at the central incisors, canines, and first molars were measured. Correlations between the ICW, IMW, and ICW/IMW ratio of archwires and the delivered forces were analyzed. The archwires were classified into the following four groups according to the ICW and IMW: Control group, ICW and IMW are within the means ± standard deviations of the normal ranges; Ovoid group, narrow ICW and IMW; Tapered group, narrow ICW; and Square group, narrow IMW. The forces were compared among these groups for each tooth.

RESULTS

Significant correlations between the measured archwire width and force to each tooth were found, except between IMW and forces at the central incisors and canines. Significant differences in the forces were found among all groups, except between the Ovoid and Tapered groups at all teeth and between the Ovoid/Tapered and Control groups at the first molar. Significantly greater orthodontic forces in the facial direction were delivered at the central incisors by the archwires in the Ovoid and Tapered groups when compared with the archwires in the other groups.

CONCLUSION

These findings suggest that there is a possible risk of a clinically significant level of unfavorable orthodontic force being delivered to the mandibular incisors in labial inclination when using a preformed archwire with an ICW that is narrower than the dental arch.