How Effective Are the Nance Appliance and Transpalatal Arch at Reinforcing Anchorage in Extraction Cases?

OBJECTIVE

This narrative review aimed to evaluate, based on current evidence, whether the transpalatal arch (TPA) and Nance appliance can effectively reinforce anchorage during fixed orthodontic treatment while also offering a comprehensive and in-depth overview of the existing literature on this subject.

MATERIALS AND METHODS

A thorough literature search was performed across multiple electronic databases to identify peer-reviewed articles relevant to the review.

RESULTS

Evidence suggests that the Nance appliance does not provide absolute anchorage. Additionally, patients experienced discomfort and inflammation of the palatal tissues. The transpalatal arch is also insufficient for maximum anteroposterior anchorage, and existing studies on its effectiveness in vertical anchorage control are inconsistent with conflicting data.

CONCLUSIONS

For patients with critical anchorage demand, mini-screws may be the method of choice, either solely or in combination with Nance or transpalatal arch, though they carry a risk of failure.

Comparison of the Mesiodistal Angulations of Canine and Molar Teeth in Different Types of Orthodontic Malocclusions: A Retrospective Study

(i) Objective: Changes in the mesiodistal axial angulations of teeth with orthodontic treatment have been a topic of interest in orthodontics for many years, although it has not been clarified enough yet. Therefore, this present study aimed to compare mesiodistal axial angulations of canine and first molar teeth by measuring from pre- and post-treatment panoramic radiographs in different types of orthodontic malocclusions. (ii) Materials and Methods: In the study, the mesiodistal axial angulation angles of the lower–upper canines (teeth numbered 13, 23, 33, and 43) and first molars (teeth numbered 16, 26, 36, and 46) were compared on panoramic radiographs taken pre- (T0) and post- (T1) orthodontic treatment of 353 patients: 237 female (mean age 14.74 ± 2.96) and 116 male (mean age 14.44 ± 2.50), who had not received any prior orthodontic treatment. The groups were formed according to pre-/post-treatment, gender, angle classification, skeletal classification, bilaterally first premolar extraction/non-extraction, and the use/non-use of miniscrews in the extraction cases. The mesiodistal angulations between the long axes of both the lower and upper canines and first molars and the interorbital plane were measured separately and recorded. The reliability analysis between the repeated measurements was evaluated using the intraclass correlation coefficient (ICC). For statistical analysis, a paired sample t-test and Wilcoxon test were used for the normally and non-normally distributed data, respectively. For the between-groups comparison, independent sample t-test and one-way ANOVA were used for normally distributed data, while the Mann–Whitney U and Kruskal–Wallis tests were used for non-normally distributed data. A value of p < 0.05 was considered statistically significant. (iii) Results: ICCs showed excellent reliability, ranging from 0.804 to 0.913 in other teeth, yet were good in tooth 43 (ICC = 0.712). Regardless of the groups, statistically significant differences were found between the T0 and T1 angulations for all teeth, except teeth 13 and 16. In all groups, the increase in the angulations of teeth 33 and 43 and the decrease in the angulations of teeth 36 and 46 (except skeletal class 3) were found to be statistically significant. The T0 and T1 angulation changes in the miniscrews in the used and non-used groups in extraction cases were similar to the differences found in all teeth, regardless of the groups. There was no significant difference between gender, skeletal classes, and angle classes in the amounts of change in the mesiodistal angulations. (iv) Conclusion: It was concluded that orthodontic treatment caused significant changes in the mesiodistal axial angulation of the canine and the first molar teeth. Furthermore, the fact that the angulations tended to increase in the lower canine teeth and decrease in the lower first molar teeth revealed the importance of tooth movement control, especially in orthodontic mechanics in the mandibula.

A Scoping Review about the Characteristics and Success-Failure Rates of Temporary Anchorage Devices in Orthodontics

This study synthesized the scientific evidence concerning the main characteristics of the Temporary Anchorage Devices (TADs) used in orthodontics and reported the success-failure rates during treatment. For that means, this scoping review collected articles from previous research. A complementary search was carried out in the databases PubMed-MEDLINE, Scopus, LILACS, and EMBASE, focusing on original studies published from 2010 to 2020. We analyzed the main characteristics of the publications. As a result, 103 articles were included. Most of the research was conducted among different groups, who needed TADs principally in the maxilla and an interradicular location between the second premolar and first molar. AbsoAnchor, Dentos Inc., Daegu, Korea, was the most used brand of TADs. The most common characteristics of the devices and biomechanics were a diameter and length of 1.6 mm and 8 mm, a self-drilled system, a closed technique for placement, immediate loading, and forces that ranged between 40 and 800 g. Of the studies, 47.6% showed success rates ≥90%. In conclusion, high success rates were found for TADs, and differences were found according to sociodemographic and clinical variables. The studies showed variability in methodological design, and scientific publications were concentrated in certain countries. We recommend further scientific research on TADs using more standardized designs.

Open and closed surgical exposure of palatally displaced canines: a cost-minimization analysis of a multicentre, randomized controlled trial

OBJECTIVE

To evaluate the costs of open and closed surgical exposure and subsequent orthodontic treatment for the correction of palatally displaced canines (PDCs).

TRIAL DESIGN

A multicentre, two-arm parallel group randomized controlled trial.

METHODS

One hundred twenty adolescents between 9 and 16 years of age, from three orthodontic specialist centres, were randomized to one of the two surgical exposure interventions. The randomization was conducted according to a two-arm parallel group 1:1 allocation ratio, using computerized lists with block randomization. In both the surgical techniques, whole mucoperiosteal flaps were raised, and bone covering the PDCs was removed. In the open technique, glass ionomer was built up on the PDC crown - reaching above the mucosa through a hole punched in the flap - to allow the canine to erupt autonomously. After eruption, the canine was orthodontically moved above the mucosa. In the closed technique, an eyelet was bonded onto the PDC, the flap was repositioned and the canine was orthodontically moved beyond the mucosa. The trial ended when the PDC was successfully aligned in the dental arch.Cost analysis was performed including costs for surgery, orthodontic treatment, emergency visits, and material, as well as costs for transports and time spent in connection with every appointment.

BLINDING

Patients and caregivers could not be blinded due to obvious limitations of the clinical setting, while outcome assessors and data analysts were blinded.

RESULTS

A cost-minimization analysis was performed since both exposure groups succeeded equally well in terms of treatment effects. The two different surgical exposures and following orthodontic treatments did not differ significantly in terms of costs.

GENERALIZABILITY AND LIMITATIONS

Costs are estimated in the Swedish setting, which needs to be considered if applying the results in other settings. Calculations of total cost do not include finishing, debonding, retention, and follow-up.

CONCLUSION

There is no significant difference in costs between closed and open surgical exposure with following orthodontic treatments in PDCs.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02186548.

Failure rates of miniscrews inserted in the maxillary tuberosity

Introduction:

Anchorage conservation in orthodontics has always been a challenge.

Objective:

The aim of this current study was to find out the failure rate of miniscrews inserted in the maxillary tuberosity (MT) region.

Methods:

This pilot study consisted of 40 patients (23 female, 17 male; mean age = 20.1±8.9 years) that had received 60 MT miniscrews for orthodontic treatment. Clinical notes and pictures were used to find out the primary outcome of miniscrew failure. Independent failure factors were also investigated. Logistic regression analysis was done for predictor’s relation with MT miniscrews failure.

Results:

There was no significant correlation in failure rate according to various predictor variables, except for miniscrews installed by lesser experienced operators, which showed significantly more failure. The odds ratio for miniscrew failure placed by inexperienced operators was 4.16.

Conclusion:

A 26.3% failure rate of mini-implants inserted in the MT region was observed.

Postoperative pain profile in 10-15-year-olds after bilateral extraction of maxillary premolars

PURPOSE

To study pain perception in 10-15-year-olds, during and after uncomplicated extractions of bilateral maxillary premolars. The study investigated pain's natural course and made comparisons between the first and second extractions.

METHODS

31 Swedish children in need of orthodontic treatment were identified and consecutively enrolled. Tooth extractions followed a standardised protocol and the two teeth were extracted with at least 10 days between. The participants rated pain intensity using visual analogue scale (VAS) at 14 different time points from treatment and 7 days forward.

RESULTS

The pain intensity profile followed the same pattern for all patients. Pain intensity peaked 2 h after extractions (mean VAS_PI 27.3, SD 20.8; median 23.0) when moderate pain intensity (VAS_PI ≥ 40) was registered for 16 (28%) of 57 cases. After that, there was a rapid decrease in pain intensity notable already at 4 h after extractions. There were no statistically significant differences in any VAS_PI measurements between the first and second extractions, sexes, or different age groups.

CONCLUSIONS

The majority of the participants who undergo uncomplicated bilateral extraction of maxillary premolars experience mild to moderate levels of postoperative pain during a short period of time, with no differences between the first and second extractions. Bilateral tooth extractions is a suitable model for further studies on pain management.