Quantitative and qualitative assessment of anchorage loss during en-masse retraction with indirectly loaded miniscrews in patients with bimaxillary protrusion

The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic treatment: a systematic review and meta-analysis

OBJECTIVES

Information on the oral health of patients with anorexia nervosa remains not satisfactory. The aim of this systematic review is to evaluate oral health parameters in anorexic patients compared to healthy individuals. Furthermore, potential clinical implications for orthodontic treatment are discussed from an orthodontic perspective.

MATERIALS AND METHODS

Electronic databases were searched for case-control and controlled clinical trial studies on dentofacial manifestations in anorexic patients up to 2/2024. Study selection, data extraction and risk of bias assessment was done independently by two authors. Random-effects meta-analyses of mean differences (MDs) or relative risks (RRs) with their 95% confidence intervals (CIs) were conducted, followed by sensitivity analyses.

RESULTS

Eleven out of 573 initially identified studies were included. They involved oral health analyses of general anorexic patients ≥ 12 years (mean age 18.4). The meta-analysis showed that anorexia nervosa was associated with a significantly increased caries experience (DMFT), plaque accumulation and gingival inflammation (BOP). PH and salivary flow rate were significantly altered in patients with anorexia nervosa, although no significant relationship between α-amylase levels and anorexia nervosa was demonstrated.

CONCLUSIONS

These data enabled us to formulate modalities for anorexia-specific orthodontic treatments. Based on the results, patients with anorexia nervosa exhibit an increased risk of caries and gingival inflammatory signs.

CLINICAL RELEVANCE

The systematic information on dentofacial manifestations obtained in this study should be considered to better manage the oral health of anorexia patients.

Identification of novel BCL11A variant in a patient with developmental delay and behavioural differences

BACKGROUND

The BCL11A gene is involved in disorders including intellectual disability syndrome (IDS), encodes a zinc finger protein highly expressed in haematopoietic and brain and acts as a transcriptional repressor of foetal haemoglobin (HbF). De novo variants in BCL11A have been associated with IDS, which is characterized by developmental delays, autism spectrum disorder (ASD) and speech and language delays. The reports of BCL11A gene variants are still limited worldwide, and additional cases are needed to expand the variant and phenotype spectrums.

METHODS

The patient is a 5-year-old girl who was hospitalized due to developmental delays. After analysing her clinical and pathological characterizations, whole-exome sequencing (WES) was performed for pathogenic genetic variants of developmental delay and behavioural differences. Candidate variant in BCL11A gene was identified and further validated by Sanger sequencing.

RESULTS

A heterozygous variant, c.1442delA (p.Glu481Glyfs*25), was identified in exon 4 of the BCL11A gene through WES. This variant results in a truncated expression of the encoded protein. This de novo variant was confirmed by Sanger sequencing. The language delay and behavioural differences were prominent in our patient.

CONCLUSION

Our finding demonstrates that BCL11A variant may cause developmental delay and behavioural differences, expanding the genetic spectrum of the BCL11A gene.

Evaluation of anchorage loss after en masse retraction in orthodontic patients with maxillary protrusion using friction vs frictionless mechanics: randomized clinical trial

OBJECTIVES

To evaluate anchorage loss after en masse retraction in bimaxillary dentoalveolar protrusion patients using friction vs frictionless mechanics.

MATERIALS AND METHODS

Thirty patients with bimaxillary dentoalveolar protrusion needing extraction of upper first premolars and en masse retraction with maximum anchorage were included in this two-arm, parallel, single-center, single-blinded randomized clinical trial with a 1:1 allocation ratio using fully sealed opaque envelopes. Friction group retraction utilized elastomeric power chain between miniscrews and hooks crimped mesial to upper canines on 17 × 25 stainless steel archwire. Frictionless group used customized T-loop springs loading upper first molars indirectly anchored to miniscrews. Activation was every 4 weeks until full retraction. The primary outcome assessed was anchorage loss evaluated at cusp tip and root apex of the first molar. First molar rotation, incisor tip and torque, and root resorption of anterior teeth were evaluated on digital models and cone beam computed tomography taken before and after space closure.

RESULTS

Anchorage loss at crown of first molar was significantly more in frictionless group by 2.1 mm (95% CI = -0.4 to 3.5), (P = .014), while there was no significant difference in anchorage loss at root apex between groups. Significant mesial in molar rotation of 6.672° (95% CI = 12.2-21.2), (P = 0.02) was greater in the frictionless group. Both groups showed comparable tip, torque, and root resorption values. No severe harms were reported. There was mild gingival overgrowth and inflammation in the frictionless group due to T-loop irritation.

CONCLUSIONS

Extra anchorage considerations are needed during en masse retraction when frictionless mechanics is implemented as higher anchorage loss and molar rotation were detected. No difference in tip, torque, and root resorption was observed.

Friction versus frictionless mechanics during maxillary en-masse retraction in adult patients with Class I bimaxillary dentoalveolar protrusion: a randomized clinical trial

BACKGROUND

Extraction space closure is a challenging phase during orthodontic treatment that affects not only the total treatment duration but also the whole treatment outcome.

OBJECTIVE

To compare the efficiency of friction and frictionless mechanics during en-masse retraction of maxillary anterior teeth in adult patients with bimaxillary dentoalveolar protrusion.

TRIAL DESIGN

Two-arm parallel group, single-center randomized clinical trial.

MATERIALS AND METHODS

Thirty-two adult patients with bimaxillary protrusion were recruited and randomly allocated to two different retraction mechanics. A friction group, using NiTi coil springs and a frictionless group using closing T-loops for en-masse retraction. Randomization in a 1:1 ratio was generated by Microsoft Excel. The randomization numbers were secured in opaque sealed envelopes for allocation concealment. Retraction started in all patients following first premolars extraction using miniscrews as a source of indirect anchorage. Activation was done on a monthly basis until complete retraction of anterior segment. The rate of retraction, amount of anchorage loss, the dental, and soft tissue changes were analyzed on digital models and lateral cephalograms taken before retraction and after space closure.

BLINDING

The outcome assessor was blinded through data concealment during assessment.

RESULTS

Two patients were lost to follow up, so 30 patients completed the trial. The rate of anterior segment retraction was 0.88 ± 0.66 mm/month in the frictionless group compared to 0.72 ± 0.36 mm/month in the friction group which was statistically significant. Anchorage loss of 1.18 ± 0.72 mm in the friction group compared to 1.29 ± 0.55 mm in the frictionless group with no significant difference. Comparable dental and soft tissue changes following en-masse retraction were reported in both groups, with no statistically significant difference.

HARM

one patient complained of soft tissue swelling following miniscrew insertion, but the swelling disappeared after one week of using mouth wash.

LIMITATION

The study focused only on the maxillary arch.

CONCLUSION

Both mechanics have successfully achieved the required treatment objectives in patients with bimaxillary dentoalveolar protrusion. Frictionless group showed a faster rate of retraction than the friction group, which was statistically but not clinically significant.

TRIAL REGISTRATION

Clinicaltrials.gov with the identifier NCT03261024.

Soft tissue changes with skeletal anchorage in comparison to conventional anchorage protocols in the treatment of bimaxillary proclination patients treated with premolar extraction : A systematic review

PURPOSE

This review systematically evaluates the evidence related to comparisons between skeletal and conventional anchorage protocols in the treatment of bimaxillary proclination patients who underwent premolars extraction with respect to soft tissue profile changes, treatment duration and three-dimensional (3D) soft tissue changes.

METHODS

Electronic database search and hand search with no language limitations were conducted in the Cochrane Library, PubMed, Ovid, Web of Science, Scopus and ClinicalTrials.gov. The selection criteria were set to include studies with patients aged 13 years and above requiring extractions of upper and lower first premolars to treat bimaxillary proclination with high anchorage demand. Risk of bias assessment was undertaken with Cochrane's Risk Of Bias tool 2.0 (ROB 2.0) for randomised controlled trials (RCTs) and ROBINS‑I tool for nonrandomised prospective studies. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach was used for quality assessment. Results were summarised qualitatively; no meta-analysis was conducted.

RESULTS

Two RCTs and two nonrandomised prospective studies were included. According to the GRADE approach, there is low to very low quality of evidence that treatment using mini-implant anchorage may significantly change nasolabial angle, upper and lower lip procumbence, and facial convexity angle compared to treatment with conventional anchorage. Similarly, very low quality evidence exists showing no differences in treatment duration between treatments with skeletal or conventional anchorage.

CONCLUSIONS

The overall existing evidence regarding the effect of anchorage protocols on soft tissue changes in patients with bimaxillary protrusion and premolar extraction treatment plans is of low quality.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42020216684.

Three-dimensional evaluation of maxillary tooth movement in extraction patients with three different miniscrew anchorage systems: a randomized controlled trial

OBJECTIVE

To compare the three-dimensional (3-D) movement of maxillary teeth in response to three common miniscrew anchorage systems in extraction patients with maxillary dentoalveolar protrusion.

MATERIALS AND METHODS

The study employed a randomized controlled single-blinded design with three arms. Thirty extraction patients who required maximum anchorage to retract maxillary anterior teeth were included and randomly allocated into three treatment groups: space closure with direct miniscrew anchorage and low crimpable hooks (DL group), indirect miniscrew anchorage and low crimpable hooks (IL group), and direct miniscrew anchorage and high crimpable hooks (DH group). Cone beam computed tomography (CBCT) images of all included patients were obtained immediately before (T0) and after (T1) space closure. The outcomes were 3-D positional changes of maxillary central incisor, lateral incisor, canine, second premolar, and first molar. The repeated measures analysis of variance with post hoc LSD test was used to evaluate differences among groups.

RESULTS

A significant intrusion (- 1.34 mm; 95% CI, - 1.60 mm, 1.08 mm) and buccal (- 6.92°; 95% CI, - 8.67°, - 5.13°) and distal (4.90°; 95% CI, 3.75°, 6.04°) inclination of the maxillary first molars were observed in the DL group, compared to the other two groups. The mesial movement (- 0.40 mm; 95% CI, - 0.83 mm, - 0.03 mm) of the maxillary first molars was found in the IL group, while the DL (0.44 mm; 95% CI, 0.15 mm, 0.73 mm) and IL (0.62 mm; 95% CI, 0.28 mm, 0.96 mm) groups exhibited distal movement. In the DH group, the lingual inclination changes of maxillary central incisor (5.04°; 95% CI, 2.82°, 7.26°) were significantly lower, which is indicative of good lingual root torque control of the maxillary anterior teeth.

CONCLUSION

Three miniscrew anchorage systems produced significantly different 3-D maxillary tooth movement. The maxillary first molars were significantly buccally and distally inclined and intruded in patients using direct miniscrew anchorages with low crimpable hooks. Direct miniscrew anchorages with high crimpable hooks could help to achieve better lingual root torque control of the maxillary incisors. Trial registration The trial was registered at www.chictr.org.cn (ChiCTR1900026960). Registered 27 October 2019.

A retrospective study of factors contributing to anchorage loss in upper premolar extraction cases

BACKGROUND

Anchorage control is one of the components in the treatment of extraction cases. However, what determines more or less anchorage loss is still an unanswered question. Aim: The purpose of this study was to investigate the most important factors contributing to the anchorage loss of maxillary first molars in premolar extraction cases.

MATERIALS AND METHODS

The study included 726 upper premolar extraction cases, including 214 male patients and 512 female patients, and the mean age was 14.4 ± 4.5 years old (range: 9-45). Factors including physiological characteristics, treatment mechanics, and cephalometric variables were collected and their influences on the angulation changes of maxillary first molars were analyzed.

RESULTS

The mean angulation change of maxillary first molar after treatment was 2.81°(mesial tipping). The change of UM/PP showed a statistically significant difference in different sex (male 3.84° ± 5.26° vs female 2.38° ± 5.10°), age (adult -0.05° ± 4.73° vs teenager 3.46° ± 5.07°), and molar relationship (Class II 3.28° ± 5.15° vs Class I 2.36° ± 5.19°). There are six variables accounted in the regression analysis (R = 0.608, R2 = 37.0%). Among them, the pre-treatment molar tipping (Standardized Coefficients: -0.65) and the pre-treatment incisor/molar height ratio (Standardized Coefficients: -0.27) were the most important factors influencing anchorage loss during treatment.

CONCLUSION

Compared with treatment-related factors, the patient's physiological characteristics play a more important role in anchorage loss. The pre-treatment angulation of the maxillary first molar is the most influential factor in changes to maxillary molar angulation, which are often predisposing anchorage loss.

Anchorage control using miniscrews in comparison to Essix appliance in treatment of postpubertal patients with Class II malocclusion using Carrière Motion Appliance

OBJECTIVES

To evaluate anchorage control using miniscrews vs an Essix appliance in treatment of Class II malocclusion by distalization using the Carrière Motion Appliance (CMA).

MATERIALS AND METHODS

Twenty-four postpubertal female patients with Class II, division 1 malocclusion were randomly distributed into two equal groups. CMA was bonded in both groups, and one group was treated with miniscrews as anchorage (12 patients, mean age = 18.0 years) while the other group was treated with an Essix appliance as anchorage (12 patients, mean age = 17.8 years). For each patient, two cone-beam computed tomographic scans were obtained: one preoperatively and another after completion of distalization.

RESULTS

In the Essix appliance group, there was a statistically significant anterior movement (2.2 ± 1.43 mm) as well as proclination of the lower incisor (5.3° ± 4.0°), compared to a nonsignificant anterior movement (0.06 ± 1.45 mm) and proclination (0.86° ± 2.22°) in the miniscrew group. The amount of maxillary molar distalization was higher in the miniscrew group (2.57 ± 1.52 mm) than in the Essix appliance group (1.53 ± 1.11 mm); however, the difference was not statistically significant.

CONCLUSIONS

Miniscrews led to a decrease in the amount of anchorage loss in the mandibular incisors, both in terms of anterior movement and proclination.

Anchorage loss assessment of the indirect anchor tooth during adjunctive orthodontic treatment

INTRODUCTION

This study quantitatively assessed movement of anchor teeth connected to a miniscrew (indirect anchor tooth) and investigated factors affecting movement during adjunctive orthodontic treatment.

METHODS

Dental plaster models of 28 patients whose treatment included an indirect anchor tooth on one side were collected before and after treatment. The casts were digitally scanned, and 2 groups were constituted: the indirect anchor teeth (experimental group; n = 52) and the untreated teeth (control group; the first and second premolars opposing the indirect anchor tooth to which no orthodontic force was applied; n = 55). Pretreatment and posttreatment models were superimposed and the amount and direction of indirect anchor tooth movement were evaluated with the use of a univariate linear mixed model. Possible factors affecting movement of the indirect anchor tooth and its significance were also evaluated with the use of a multiple linear mixed model.

RESULTS

The indirect anchor tooth moved 0.91 ± 0.50 mm and did not exhibit significant differences in the transverse, vertical, or sagittal directions. The location of the indirect anchor tooth affected movement and the tooth moved significantly more in the mandible than in the maxilla.

CONCLUSIONS

The indirect anchor tooth can move during adjunctive orthodontic treatment and thus requires careful monitoring for occlusal changes.

Efficacy of orthodontic mini implants for en masse retraction in the maxilla: a systematic review and meta-analysis

Background/aim

Retraction of the upper incisors/canines requires maximum anchorage. The aim of the present study was to analyze the efficacy of mini implants in comparison to conventional devices in patients with need for en masse retraction of the front teeth in the upper jaw.

Material and methods

An electronic search of PubMed, Web of Science, and EMBASE and hand searching were performed. Relevant articles were assessed, and data were extracted for statistical analysis. A random effects model, weighted mean differences (WMD), and 95% confidence intervals (CI) were computed for horizontal and vertical anchorage loss at the first molars in the analyzed patient treatments.

Results

A total of seven RCTs employing direct anchorage through implants in the alveolar ridge were finally considered for qualitative and quantitative analysis, and further five publications were considered for the qualitative analysis only (three studies: indirect anchorage through implant in the mid-palate, two studies: direct/indirect anchorage in the alveolar ridge). In the control groups, anchorage was achieved through transpalatal arches, headgear, Nance buttons, intrusion arches, and differential moments.

WMD [95% CI, p] in anchorage loss between test and control groups amounted to − 2.79 mm [− 3.56 to − 2.03 mm, p < 0.001] in the horizontal and − 1.76 mm [− 2.56 to − 0.97, p < 0.001] favoring skeletal anchorage over control measures. The qualitative analysis revealed that minor anchorage loss can be associated with indirect anchorage, whereas anchorage gain was commonly associated with direct anchorage. Implant failures were comparable for both anchorage modalities (direct 9.9%, indirect 8.6%).

Conclusion

Within its limitations, the meta-analysis revealed that maximum anchorage en masse retraction can be achieved by orthodontic mini implants and direct anchorage; however, the ideal implant location (palate versus alveolar ridge) and the beneficial effect of direct over indirect anchorage needs to be further evaluated.

Electronic supplementary material

The online version of this article (10.1186/s40729-018-0144-4) contains supplementary material, which is available to authorized users.

Miniscrew biomechanics: Guidelines for the use of rigid indirect anchorage mechanics

Indirect anchorage is an established form of anchorage provided by orthodontic miniscrews. Although there are different ways to set up the mechanics, rigid indirect anchorage offers the greatest biomechanical versatility but is more difficult to install than conventional, nonrigid indirect anchorage or direct anchorage. The purpose of this article was to introduce readers to the concept of rigid indirect anchorage and provide guidelines as to its use.