Orthodontic management of a complete and an incomplete maxillary canine-first premolar transposition

Mandibular lateral incisor-first premolar transposition in early mixed dentition: a rare case

Dental transposition is an anomaly of eruption which is usually seen in the maxilla and rarely in the mandible. The mandibular lateral incisor's transposition with the permanent canine has a prevalence of less than 0.03%. The following case presents an even rarer situation, of a right lateral mandibular incisor that erupted in the place of the first premolar, in transposition with the temporary canine. In the first phase, a series of extractions have been performed, to ensure the necessary free space for moving the lateral incisor closer to its appropriate place, and after that a fixed orthodontic appliance was used. The biomechanics for intra-arch tooth movement was ingenious enough to ensure a perfect alignment of all permanent teeth and a functional Class I canine and molar final occlusion. Early intervention and successful move of the permanent canine in its correct position ensured the functionality of the mandibular movements and a good long-term prognosis.

Modified orthodontic treatment of substitution of canines by first premolars: A case report

BACKGROUND

Canines are the most important teeth in the dentition. Usually, doctors choose to remove premolars rather than canines. Canine extraction is extremely rare in orthodontic treatment. However, dentists sometimes encounter situations in which canines require extraction due to defects caused by improper medical treatment.

CASE SUMMARY

The present study reports a case of a class II adult patient treated with the extraction of maxillary canines and right mandibular second premolar. After postactive treatment for 28 mo, then the canines were substituted by the upper first premolar, a satisfactory occlusal was established, the lips were competent, and the profile was improved. Intraoral pictures and X-ray data retrieved 3 years after the end of orthodontic treatment demonstrated the possibility of canine extraction and premolar substitution of canines in function and beauty.

CONCLUSION

The extraction of canines and substitution by first premolars could be a feasible orthodontic treatment.

Cantilevers: Multi-Tool in Orthodontic Treatment

This review aims to discuss and illustrate various uses of cantilevers to solve multiple clinical issues and prove their versatility. Cantilevers are commonly used in the segmented arch technique, and they can be designed to solve various clinical problems with highly predictable results. Its design and shape can modify the various combinations of vertical and horizontal forces. The novel trend is to combine cantilevers with skeletal anchorage. Cantilevers offer a very simple and statically determined force system. The advantage is the control over side effects, which normally occur on the anchor teeth and the occlusion. The disadvantages include possible side effects on the anchorage unit, when the anchorage is poorly controlled. The review highlights the clear benefits of cantilever use in complex corrections of single teeth, segments, and entire arch with a diminished effect on the dentition, also with the use of skeletal anchorage. With their simple and easily tailored design, these springs can be called an orthodontic multi-tool.

Force Systems Produced by Different Cantilever Configurations during Deactivation

Intrusion with a three-piece arch is routinely achieved during orthodontic treatment. This study aimed to experimentally determine how the cantilever design influences the generated force system. Both straight and arch-formed cantilever designs: tip-back (TB), flat curve (FC) deep curve (DC), and 3 mm and 6 mm high utility arch (UA3; UA6) were activated for 5 mm and 10 mm. Force systems were determined by a hexapod. Typodonts simulating a three piece-intrusion arch were scanned using an intraoral scanner (3Shape, TRIOS, Denmark) before (T0) and after (T1) the experiment and superimposed with Mimics software (Materialise, Leuven, Belgium). Data were analyzed. All straight designs displayed an extrusive force in the vertical plane, and all arch-formed an intrusive force. DC and TB showed a retrusive force in the sagittal plane and UA6 a protrusive. For the medial/lateral forces, DC and TB displayed a medial, and UA6 a lateral force. Configurations can be distinctively ranked from DC, FC, TB to UA3, and UA6 according to the increasing protrusive nature of the generated sagittal forces. A DC or TB configuration should be used for intrusion and retraction, while for an intrusion and a protrusion, a UA6 configuration. All straight configurations showed a higher force level than the arch-formed configurations.

Orthodontic Treatment and Healthcare Goals: Evaluation of Multibrackets Treatment Results Using PAR Index (Peer Assessment Rating)

BACKGROUND

The evaluation of orthodontic treatment outcomes using an objective method is important in order to maintain high treatment quality and final healthcare of patients. It allows professionals and university students to raise the level of the therapy. The aim of this study was to assess the orthodontic treatment outcomes in an Italian postgraduate School of Orthodontics using Peer Assessment Rating (PAR) Index.

METHODS

A sample of 50 patients treated in a postgraduate program was randomly selected. PAR index was used to assess pre-treatment and post-treatment study casts by two different examiners. The influence of different variables such as gender, treatment method, and need for extraction was statistically analyzed.

RESULTS

The average numerical reduction of PAR between the beginning and the end of the treatment was 18.74 (CI 95% 16.53-20.95), while the percentage reduction was 94.8% (CI 95% 91.91-97.68). All cases improved: 8% of patients resulted in the improved category, while 92% of them were in the greatly improved group.

CONCLUSIONS

According to PAR index, the results showed that patients received a high-standard therapy. None of the factors studied influenced significantly the treatment outcomes.