Maxillary molar distalization therapy in adult patients: a multicentre study.

OBJECTIVES: To evaluate dento-skeletal changes following conventional anchorage molar distalization therapy in adult patients. SETTING AND SAMPLE POPULATION: Thirty-three patients (25 women, mean age 23 years 1 months ± 3 months; 8 men, mean age 28 years 3 months ± 7 months) were recruited from 4 Board Certified specialists. All subjects underwent molar distalization therapy using intra-oral distalizing appliances. SUBJECTS AND METHODS: Cephalometric headfilms were available for all subjects before (T1) and at the end of comprehensive treatment (T2). The initial and final measurements and treatment changes were compared by means of a paired t-test. RESULTS: Mean total treatment time was 3 years 2 months ± 6 months. Maxillary first molar distalized 2.9 ± 0.6 mm contributing 64.4% to Class II molar correction, whereas mandibular first molar showed a concomitant mesial movement of 1.6 ± 0.5 mm. Maxillary incisors retroclined an average of 5.8° ± 3.9°, lower incisors proclined 4.1° ± 1.1° and the occlusal plane rotated downwards and backwards 1.8° ± 2.1°. Clockwise rotation of the mandible (1.7° ± 0.5°) and increase in lower facial height (2.5 ± 1.5 mm) were also observed. CONCLUSIONS: Maxillary molar distalization therapy can be successfully performed in adult patients despite a slight increase in vertical facial dimension should be considered.

Class II treatment of transverse maxillary deficiency with a single bone-borne appliance and hybrid clear aligner approach in an adult patient: A case report.

This case report describes the successful orthodontic treatment of a 22-year-old female patient affected by Class II malocclusion, maxillary skeletal transverse deficiency, ectopic maxillary left lateral incisor, and mild mandibular crowding. Due to her adult skeletal age, a bone-borne appliance was applied in order to obtain both purely skeletal rapid maxillary expansion and bilateral molar distalization. After accurate matching between the pretreatment cone-beam computed tomography scan and digital models, 4 self-drilling miniscrews were inserted palatally using a computer-aided design and computer-aided manufacturing (CAD/CAM) surgical template to guide their correct and safe placement, and a bone-borne appliance was fitted. After this first phase, the hybrid clear aligner approach was used to obtain alignment, levelling, and arch coordination, with the use of a partial lingual fixed appliance on the maxillary incisors.

Clinical effectiveness of space maintainers and space regainers in the mixed dentition: A systematic review.

BACKGROUND: The aim of this systematic review was to address the clinical effectiveness of space maintainers and space regainers in the prevention and correction of dental arch decreases in mixed dentition. METHODS: An electronic search was conducted using five databases: the Cochrane Database for Systematic Reviews, EBSCO Host, ScienceDirect, PubMed, and Scopus (until February 2021) and 6 relevant journals. Inclusion criteria were: Randomized Controlled Clinical Trials (RCTs), Controlled Clinical Trials (CCTs), cohort studies and case-control studies of children in the mixed dentition requiring a space maintainer or a space regainer, children with mild to moderate crowding, and with Class I and mild Class II or Class III skeletal pattern. All articles included in this review were examined independently by three teams of investigators to assess the level of bias using the Cochrane risk of bias tools RoB 2.0 (for RCTs) and ROBINS-I (for non-RCTs). RESULTS: Following the three phases of a systematic search, 11 studies were included for the final analysis, of which nine used space maintainers (a lower lingual arch) and two used space regainers (one lip bumper and one transpalatal arch) with contradicting results. Four of the former and one of the latter devices showed a significant increase in arch length. Out of the 11 articles, one was found to be of critical risk, two of serious risk and eight of moderate risk of bias. CONCLUSIONS: There is very low evidence to suggest that space maintainers and regainers are effective in preserving arch length and preventing mild to moderate crowding in children during the mixed dentition stage at the expense of lower incisor proclination. However, considering the low evidence provided by this systematic review, high-quality studies are needed.

Class II subdivision with skeletal transverse maxillary deficit treated by single-sitting bone-borne appliance.

This case report describes orthodontic treatment including both skeletal maxillary expansion and unilateral distalization by means of a single bone-borne appliance followed by clear aligner therapy in a young adult patient. A surgical guide was digitally designed and three-dimensionally printed to facilitate the placement of four miniscrews in the palatal vault. The miniscrews were fitted and the bone-borne appliance was delivered in a single clinical appointment. The postexpansion photographic records and models demonstrate the opening of the palatal median suture, the pure skeletal expansion, and the resolution of the left crossbite after 40 activations. Specifically, left molar Class I was obtained in about 5 months without any loss of anterior anchorage, and the subsequent aligner phase achieved all of the objectives established in the treatment plan. This case report shows clearly how careful digital planning of miniscrew insertion and the delivery of a pure bone-borne appliance in a single sitting enabled good clinical outcomes to be achieved in an acceptable timeframe, without side effects, even in a young adult patient.

A three-dimensional finite element analysis of molar distalization with a palatal plate, pendulum, and headgear according to molar eruption stage.

OBJECTIVE: This study aimed to (1) evaluate the effects of maxillary second and third molar eruption status on the distalization of first molars with a modified palatal anchorage plate (MPAP), and (2) compare the results to the outcomes of the use of a pendulum and that of a headgear using three-dimensional finite element analysis. METHODS: Three eruption stages were established: an erupting second molar at the cervical one-third of the first molar root (Stage 1), a fully erupted second molar (Stage 2), and an erupting third molar at the cervical one-third of the second molar root (Stage 3). Retraction forces were applied via three anchorage appliance models: an MPAP with bracket and archwire, a bone-anchored pendulum appliance, and cervical-pull headgear. RESULTS: An MPAP showed greater root movement of the first molar than crown movement, and this was more noticeable in Stages 2 and 3. With the other devices, the first molar showed distal tipping. Transversely, the first molar had mesial-out rotation with headgear and mesial-in rotation with the other devices. Vertically, the first molar was intruded with an MPAP, and extruded with the other appliances. CONCLUSIONS: The second molar eruption stage had an effect on molar distalization, but the third molar follicle had no effect. The application of an MPAP may be an effective treatment option for maxillary molar distalization.

Analysis of midpalatal miniscrew-assisted maxillary molar distalization patterns with simultaneous use of fixed appliances: A preliminary study.

Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required.

Treatment effects of mandibular total arch distalization using a ramal plate.

OBJECTIVE: The purpose of this study was to evaluate treatment effects after distalization of the mandibular dentition using ramal plates through lateral cephalograms. METHODS: Pre- and post-treatment lateral cephalograms and dental casts of 22 adult patients (11 males and 11 females; mean age, 23.9 ± 5.52 years) who received ramal plates for mandibular molar distalization were analyzed. The treatment effects and amount of distalization of the mandibular molars were calculated and tested for statistical significance. The significance level was set at p < 0.001. RESULTS: The mandibular first molar distalization at the crown and root were 2.10 mm (p < 0.001) and 0.81 mm (p = 0.011), respectively. In the evaluation of skeletal variables, there was a significant increase in the Wits appraisal (p < 0.001). In the evaluation of the soft tissue, there was no significant effect on upper lip position, but the lower lips showed a significant retraction of 2.2 mm (p < 0.001). CONCLUSIONS: The mandibular molars showed a significant amount of distalization accompanied by limited extrusion and mesiobuccal rotation of the crowns. A ramal plate may be a viable device for mandibular total arch distalization in Class III patients who are reluctant to undergo orthognathic surgery.

Comparison between direct vs indirect anchorage in two miniscrew-supported distalizing devices.

OBJECTIVE: To compare two distalizing devices supported by palatal miniscrews, the MGBM System (MGBM) and the Distal Screw appliance (DS), in dental Class II patients. MATERIALS AND METHODS: Pretreatment (T1) and postdistalization (T2) lateral cephalograms of 53 Class II malocclusion subjects were examined. MGBM consisted of 29 patients (16 males, 13 females) with a mean pretreatment age of 12.3 ± 1.5 years; DS consisted of 24 patients (11 males, 13 females) with a mean pretreatment age of 11.3 ± 1.2 years. The mean distalization time was 6 ± 2 months for MGBM and 9 ± 2 months for DS. Initial and final measurements and treatment changes were compared by means of a Student's t-test. RESULTS: Maxillary superimpositions showed that the maxillary first molar distalized an average of 5.5 mm in the MGBM and 3.2 mm in the DS between T1 and T2; distal molar tipping was greater in the MGBM (10.3°) than in the DS (3.0°). First premolar showed a mean mesial movement of 1.4 mm, with a mesial tipping of 4.4° in the MGBM; on the contrary, first premolar showed a distal movement of 2.2 mm, with a distal tipping of 6.2°, in the DS. CONCLUSIONS: The MGBM system resulted in greater distal molar movement and less treatment time, resulting in more efficient movement than was associated with the DS; DS showed less molar tipping during distalization.

Comparative evaluation of molar distalization therapy using pendulum and distal screw appliances.

OBJECTIVE: To compare dentoalveolar and skeletal changes produced by the pendulum appliance (PA) and the distal screw appliance (DS) in Class II patients. METHODS: Forty-three patients (19 men, 24 women) with Class II malocclusion were retrospectively selected for the study. Twenty-four patients (mean age, 12.2 ± 1.5 years) were treated with the PA, and 19 patients (mean age, 11.3 ± 1.9 years) were treated with the DS. The mean distalization time was 7 months for the PA group and 9 months for the DS group. Lateral cephalograms were obtained at T1, before treatment, and at T2, the end of distalization. A Mann-Whitney U test was used for statistical comparisons of the two groups between T1 and T2. RESULTS: PA and DS were equally effective in distalizing maxillary molars (4.7 mm and 4.2 mm, respectively) between T1 and T2; however, the maxillary first molars showed less distal tipping in the DS group than in the PA group (3.2° vs. 9.0°, respectively). Moreover, significant premolar anchorage loss (2.7 mm) and incisor proclination (5.0°) were noted in the PA group, whereas premolar distal movement (1.9 mm) and no significant changes at the incisor (0.1°) were observed in the DS group. No significant sagittal or vertical skeletal changes were detected between the two groups during the distalization phase. CONCLUSIONS: PA and DS seem to be equally effective in distalizing maxillary molars; however, greater distal molar tipping and premolar anchorage loss can be expected using PA.

Comparative evaluation of molar distalization therapy with erupted second molar: Segmented versus Quad Pendulum appliance.

BACKGROUND: There are controversial opinions about the effect of erupted second molars on distalization of the first molars. Most of the distalizing devices are anchored on the first molars, without including second molars; so, differences between sequentially distalize maxillary molars (second molar followed by the first molar) or distalize second and first molars together are not clear. The aim of the study was to compare sequential versus simultaneous molar distalization therapy with erupted second molar using two different modified Pendulum appliances followed by fixed appliances. METHODS: The treatment sample consisted of 35 class II malocclusion subjects, divided in two groups: group 1 consisted of 24 patients (13 males and 11 females) with a mean pre-treatment age of 12.9 years, treated with the Segmented Pendulum (SP) and fixed appliances; group 2 consisted of 11 patients (6 males and 5 females) with a mean pre-treatment age of 13.2 years, treated with the Quad Pendulum (QP) and fixed appliances. Lateral cephalograms were obtained before treatment (T1), at the end of distalization (T2), and at the end of orthodontic fixed appliance therapy (T3). A Student t test was used to identify significant between-group differences between T1 to T2, T2 to T3, and T1 to T3. RESULTS: QP and SP were equally effective in distalizing maxillary molars (3.5 and 4 mm, respectively) between T1 and T2; however, the maxillary first molar showed less distal tipping (4.6° vs. 9.6°) and more extrusion (1.1 vs. 0.2 mm) in the QP group than in the SP group, as well as the vertical facial dimension, which increased more in the QP group (1.2°) than in the SP group (0.7°). At T3, the QP group maintained greater increase in lower anterior facial height and molar extrusion and decrease in overbite than the SP group. CONCLUSION: Quad Pendulum seems to have greater increase in vertical dimension and molar extrusion than the Segmented Pendulum.

Distal jet modification: an option in distalization / Modificación del distal jet: una opción en distalización

The objective of the present study was to describe how a distalizer can be made so that some failures existing in these devices can also be eliminated. Because such devices are easy to make and have a low cost, they are becoming a viable option for treating Class II malocclusions without extraction regardless of the patient’s co-operation.

El objetivo del presente estudio fue describir cómo un distalizador puede ser hecho de modo que algunos fracasos existentes en estos dispositivos también pueden ser eliminados. Debido a que estos dispositivos son fáciles de hacer y tienen un bajo costo, se están convirtiendo en una opción viable para el tratamiento de pacientes con maloclusiones clase II sin extracción independientemente de su cooperación.