Mattia Fontana

Non-compliance maxillary molar distalizing appliances: an overview of the last decade

OBJECTIVES To perform a literature review focusing on the use of non-compliance intraoral appliances for molar distalization therapy. MATERIALS AND METHODS A literature search ranged from January 1999 to December 2009 in order to describe dento-alveolar changes and skeletal vertical modifications following the use of conventional anchorage intraoral distalizing appliances. The quality of the retrieved studies was ranked on a 12-points scale, from low to high quality. RESULTS A total of 214 articles were found and only 24 were considered eligible for the critical examination. Maxillary first molar distalization ranged from 6.4mm to 0.5mm with a concomitant distal tipping from 18.5° to bodily distalization. A smaller amount of distal movement and a greater amount of crown tipping can be noted at second molars. Premolar anchorage loss and incisor proclination represent an unavoidable side-effect and ranged from 4.33 mm to 0.73 mm and from 13.7° to 0.6° respectively. Skeletal vertical modifications were noted. Increase in vertical facial dimension ranged from 1.5° to -1.8° and lower anterior facial height ranged from an increase of 3.2 to a decrease of 0.6 mm. The assessment of study quality showed that 19 studies were of low quality, 3 of medium quality and 2 of medium-high quality. CONCLUSIONS Maxillary molar distalization can be effectively performed with the use of noncompliance intraoral appliances. As a consequence, premolar anchorage loss, incisor proclination and a slight increase in vertical facial dimension can occur. Because of the lack of high-quality studies the findings of this review should be carefully interpreted.

Long-term evaluation of the molar movements following Pendulum and fixed appliances.

OBJECTIVE To describe the molar movements and skeletal changes associated with Pendulum-fixed appliance treatment and the long-term postretention period. SUBJECTS AND METHODS The treatment sample consisted of 76 Class II patients, 35 males and 41 females. Lateral cephalograms were obtained at the start of treatment (T1); the end of distalization (T2); the end of orthodontic fixed appliance therapy (T3); and long-term observation (7 years 2 months later; T4). Mean age was 12 years 11 months at T1, 13 years 8 months at T2, 15 years 4 months at T3, and 22 years 5 months at T4. The average amount of Class II molar relationship was 3.1 mm, with a mean overjet of 5.9 mm at the beginning of treatment. A paired t-test was used to identify significant between-group differences between T2-T4 and T3-T4. RESULTS Distal molar movement was obtained during the distalization phase (T2), and more than half of the distalizing effect was maintained at the end of maxillary growth (T4). Most of the relapse occurred during fixed appliance therapy (T3), whereas no significant change was detected in the postretention period (T4). The molar relationship did not show any significant difference between T2 and T4. The vertical facial dimension increased during the distalization phase (T2) and fixed appliance therapy (T3) but returned to the initial values during the postretention period (T4). CONCLUSIONS The Pendulum appliance induces significant dentoalveolar effects, which can be partially maintained during the long-term period. The Class I molar relationship does not change during completion of individual growth. Increase in vertical facial dimension represents a temporary effect.

Soft tissue, skeletal and dentoalveolar changes following conventional anchorage molar distalization therapy in class II Non-growing subjects: a multicentric retrospective study

OBJECTIVES The purpose of this retrospective prolective study is to evaluate soft tissue, dentoalveolar and skeletal vertical changes following conventional anchorage molar distalization therapy in adult patients. MATERIALS AND METHODS Forty-six patients (34 females, mean age 25 years 6 months; and 12 males, mean age 28 years 4 months) were recruited from 4 specialists Board Certified. All subjects underwent molar distalization therapy according different distalization mechanics. Cephalometric headfilms were available for all subjects before (T0) and at the end of comprehensive treatment (T1). The initial and final measurements and treatment changes were compared by means of a paired t-test or a paired Wilcoxon test. RESULTS Mean total treatment time was 3 years 3 months ± 8 months. Maxillary first and second molars distalized 2.16±0.84 mm and 2.01±0.69 mm respectively, but also maintained a slight distal tipping of 1.45° (min 2.22°, max -6.45°) and 3.35° (min 0.47°, max -15.48°) at the end of treatment. Distal movement of maxillary first molar contributed 57.6% to molar correction, and 42.4% was due to a mesial movement of mandibular first molar (1.59±0.46 mm). Dentoalveolar changes contributed to overjet correction; maxillary incisors retroclined 5.78°±3.17°, lower incisors proclined 7.49°±4.52° and occlusal plane rotated down and backward 2.32°±2.10°. A significant clockwise rotation of the mandible (1.97°±1.32°) and a significant increase in lower facial height (3.35±1.48) mm were observed. Upper lip slightly retruded (-1.76±1.70 mm) and lower lip protruded (0.96±0.99 mm) but these changes had a negligible impact on clinical appearance. CONCLUSIONS Although maxillary molar distalization therapy can be performed in adult patients, significant proclination of the lower incisors, clockwise rotation of the occlusal plane and increase in vertical facial dimension should be expected. Nevertheless, in absence of maxillary third molars and in presence of mandibular third molars this procedure could be recommended.

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.

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 Students 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.

Macrodontic maxillary incisor in alagille syndrome

This case report describes the surgical-orthodontic guided-eruption of a deeply impacted macrodontic maxillary central incisor in a 10-year-old patient with Alagille syndrome (ALGS). In the first stage, orthodontic treatment with fixed appliance on deciduous teeth allowed to create enough space for the eruption of the maxillary right central incisor. The second stage included closed surgical exposure and vertical traction. After impacted tooth erupted in the proper position, accessory periodontal treatment and dental reshaping procedures may be indicated to camouflage macrodontic incisor with the adjacent teeth. This is the first report that presents a patient with ALGS undergoing orthodontic and surgical treatment.