Comparison of the skeletal, dentoalveolar, and periodontal changes after Ni-Ti leaf spring expander and rapid maxillary expansion: a three-dimensional CBCT based evaluation.

BACKGROUND: The aim of the present study was twofold:(1) three-dimensionally evaluate the quantitative skeletal and dentoalveolar changes after Ni-Ti leaf spring expander (leaf expander) and rapid maxillary expansion (RME) in mixed dentition patients;(2) analyze the modifications of the buccal alveolar bone plate of the maxillary first permanent molars. METHODS: Patients who underwent CBCT scans before and after maxillary expansion were randomly selected from the records archived at the Department of Biomedical Surgical and Dental Sciences, University of Milan, Italy. Inclusion criteria were the following: no systemic disease or syndromes; maxillary transverse deficiencies (difference between the upper intermolar width and the lower intermolar width of at least 3 mm and/or clinical need based on radiographic evaluation), early mixed dentition with ages between 7 to 10 years old; cervical vertebra maturation stage (CVMS) 1 or 2; no pathologic periodontal status; skeletal class I or II; maxillary expander cemented on the upper second deciduous molars. Exclusion criteria were the following: patients with pubertal or post-pubertal stage of development (CVMS 3-6); late deciduous or late mixed dentition, impossibility to use the second primary molar as anchorage; skeletal class III malocclusion; craniofacial syndromes; patients unable to be followed during the treatment period. Twenty-three patients treated with Leaf Expander, 11 males (mean age 7.8 ± 0.6 years) and 12 females (mean age 8.1 ± 0.8 years), met the inclusion criteria and constituted the case group. Twenty-four (control group) treated with conventional RME, 12 males (mean age 8.4 ± 0.9 years) and 12 females (mean age 8.1 ± 0.7 years). The paired-sample T test was used for intra-group comparison to evaluate the difference between before (T1) and after (T2) maxillary expansion. Independent sample t-test was computed to perform between groups comparison of the skeletal, dentoalveolar, and periodontal changes. RESULTS: The Leaf Expander and RME group showed a significant increase between T1 and T2 for most of the skeletal and dentoalveolar variables. Concerning the skeletal variables only the RME demonstrated a significant increase at the level of the posterior nasal (PNW) and apical base width (PABW) and maxillary mid-alveolar width (MMW). Despite this, when compare with the Leaf Expander, the RME group exhibited a statistically larger width increase for only two skeletal parameters: PNW (p = 0.03) and MMW (p = 0.02). No significant changes at the periodontal level were found in either group. CONCLUSIONS: According to the current research, the authors confirm the effectiveness of the Leaf Expander and RME to produce similar skeletal and dentoalveolar effects in mixed dentition subjects. Moreover, the devices anchored to deciduous teeth did not reduce the thickness and height of the buccal bone at the level of the maxillary permanent first molars in either of the two groups.

Evaluation of Enamel Surfaces after Different Techniques of Interproximal Enamel Reduction.

According to the literature, interproximal enamel reduction (IER) has become a consolidated technique used in orthodontic treatments to gain space in particular situations such as dental crowding, non-extractive therapies, tooth-size discrepancies, and prevention of dental relapse. There are different methods to realize stripping, and enamel surfaces resulting after this procedure can be analyzed with SEM. The aim of this study was to analyze how different devices of IER leave the surface of the teeth. One hundred and sixty freshly extracted, intact human lower incisors were included in the study, fixed in a plaster support, and then processed with four different techniques of enamel reduction and finishing. Then, they were divided randomly into eight groups (A1-A2, B1-B2, C1-C2, D, and E), each containing twenty teeth. The A, B, and C groups were divided into two subgroups and then all the teeth were observed at SEM. Each digital image acquired by SEM showed that there were streaks on the surfaces, due to the cutter used. The results of this study showed that only group C2 (tungsten carbide bur followed by twelve steps of medium-fine-ultrafine 3M Soft Lex disks) has a few line, which is very similar to group E (untreated group), while the other groups have a lot of lines and show a rougher final surface.

Maxillary dento-skeletal outcomes after orthopedic forward (class III) and backward (class II) traction in growing subjects.

BACKGROUND: This retrospective study investigated the treatment effects produced by two orthopedic appliances, an extraoral orthopedic traction on Stephenson plate (SP) in skeletal Class II malocclusion and Delaire Facial Mask (FM) in skeletal Class III malocclusion. METHODS: FM Group comprised 25 patients (13 males; 12 females, mean age 9.3 years, CS 1-2) undergoing Delaire Facial Mask therapy (mean treatment duration 1.5 years ± 1.2, 700-800 gr per side). SP Group comprised 24 patients (9 males; 15 females, mean age 10.5 years ± 1.9, CS 1-3) treated with extraoral orthopedic traction on Stephenson plate (mean treatment duration 1.6 years ± 0.8, 700-900 gr per side). For all subjects lateral cephalograms before (T0) and after (T1) therapy were obtained and traced. Descriptive statistics, t-test and Shapiro-Wilks test were calculated for each variable. RESULTS: A mesial movement of the maxillary bone of 2.4 mm in the FM group and a distal movement in the PS group (0.4 mm) was found. SNA° was reduced 1.4° after SP and increased 0.7° after FM. The overjet decreased by 4 mm after SP, while it grew after FM by 2.4 mm, as well as molars relationships (4.5 vs. 0.8 mm). CONCLUSIONS: Facemask induced greater skeletal movements than extraoral traction on Stephenson plate. PS produced a limited downward movement of the whole maxilla together with notable incisors and molars back corrections. Based on our results, it could be speculated that orthopedic mesial traction of maxillary bone may result easier than the distal movement.

Efficiency in the correction of Class II division 1 malocclusions with prominent upper incisors and increased overjet: a comparison between two methods.

BACKGROUND: The aim of the present study was to evaluate the efficiency and effectiveness of high-pull traction on a Stephenson plate as well as cervical headgear treatments in Class II Division 1 growing subjects with prominent upper teeth and an increased overjet. METHODS: A prospective study was undertaken, involving participants who underwent maxillary correction of Class II malocclusions. Twenty-three patients (Stephenson plate group, SPG, mean age 10.4±0.9 years) were treated and compared with 24 subjects treated with headgear (HGG, mean age 9.6±1.2 years). Lateral cephalograms were analysed using Jarabak and Pancherz analysis. Shapiro-Wilk's and Student's t tests were applied. RESULTS: The SPG showed significant decreases in the overjet (-4.1 versus -0.8 mm) and molar relationship (-6.1 versus -1.5 mm). A significant upper-incisor correction was found in SPG (1/SpP -10.3° versus + 2.2°). SNA (-1.4 versus 0.3°) and WITS (-1 versus 0.3 mm) were reduced in SPG, showing a partial maxillary restraint. In SPG, the overjet correction (4.1 mm) was mainly due to the dental component (65.9%) and occurred almost completely in the maxilla (92.7%); the molar relationships improvement of 6.1 mm was mainly dental (77%); in HGG, the reduction of the overjet was limited (-0.8 mm), and the skeletal maxillary contribution was negligible. CONCLUSIONS: The high-pull traction on the Stephenson plate was more efficient and effective than HG in the treatment of Class II dentoskeletal malocclusions with prominent upper teeth and a severe overjet; the overjet reduction was obtained at approximately 6 months, contributing to the substantial Class II correction.

Efficacy of professional hygiene and prophylaxis on preventing plaque increase in orthodontic patients with multibracket appliances: a systematic review.

BACKGROUND: Plaque increase is a troubling side-effect of fixed orthodontic therapy. This generally arise as a consequence of long-term difficulty in maintaining adequate oral hygiene while wearing multibracket appliances. Demineralization, also known as white spot, causes particular concern as it spoils the aesthetic outcome of the treatment itself, not to mention the integrity of the enamel. OBJECTIVES: To collate the existing literature by evaluating the efficacy of dental hygienist intervention on plaque increase in fixed orthodontics patients. MATERIALS AND METHODS: A targeted search of the Medline database (Entrez PubMed), EMBASE, and CENTRAL using relevant Medical Subject Headings was performed. The articles selected were all published before June 2013 and comprised randomized clinical trials, prospective longitudinal controlled clinical trials, and before/after studies onto the plaque increase of fixed appliances. RESULTS: The search strategy yielded 630 articles. Following the application of inclusion and exclusion criteria, 10 articles qualified for the final review. CONCLUSION: The quality of the retrieved researches ranged from low (one study) to high (one study). Six controlled trials were considered at unknown risk of bias. Data showed that regular patient motivation sessions and mechanical tooth cleaning by a professional dental hygienist help maintaining good oral hygiene during fixed orthodontics.

Early diagnostic evaluation of mandibular symmetry using orthopantomogram.

AIMS: The aim of this research was to complete Habets's method on orthopantomogram, in order to measure mandibular symmetry horizontally and diagonally in mixed dentition as the first diagnostic evaluation. SETTINGS AND DESIGN: Mixed dentition subjects were consecutively selected according to skeletal maturity. MATERIALS AND METHODS: Inclusion criteria were: Mixed dentition, cervical vertebral stages 1-2, Class II or Class III malocclusions, with or without unilateral posterior cross-bite. Fourteen subjects with cross-bite (mean age 8 y, 9 m) cross group (CG) and 14 subjects with normal transverse occlusion (mean age 8 y, 6m) non-cross group (NCG) were selected. Nine measurements were determined. An asymmetry index was performed for all linear variables. STATISTICAL ANALYSIS USED: NCG patients' data were compared with CG data using parametric t-tests. Probabilities of <0.05 were accepted as significant. RESULTS: In CG, comparing right and left side, single values showed no significant differences up to 6% (twice if compared to the 3% threshold value). T-tests showed statistically significant differences between the groups for ramus + condyle height (index 2.5% vs 4.5%, P = 0.04), condylar height (index 3.7% vs 6.6%, P = 0.02) and mandibular length (index 1.4% vs 2.3%, P = 0.04). Overall CG group was more asymmetrical than NCG. CONCLUSIONS: In mixed dentition (CS1-2), a first appraisal of mandibular symmetry may be performed on orthopantomogram utilizing this modified Habets's method. This tracing method provides an early evaluation about mandibular symmetry and is able to show slight asymmetries in mixed dentition thereby reducing the number of cone beam computed tomograms performed.

Surgical orthodontic treatment of an impacted canine in the presence of dens invaginatus and follicular cyst.

Introduction. "Dens invaginatus" is a dental anomaly which originates from the invagination of the ameloblastic epithelium into the lingual surface of the dental crown during the odontogenesis. It can cause early pulpal necrosis, abscesses, retention or dislocation of contiguous elements, cysts, and internal resorptions. It normally affects the upper lateral incisors. In the following study the authors will discuss the etiology, the physiopathology, and the surgical-orthodontic management of a rare case of impacted canine associated with dens invaginatus and follicular cyst, with the aim of highlighting the importance of taking any therapeutic decision based on the data available in the literature. Case Report. The present study describes a combined surgical-orthodontic treatment of an impacted canine associated with a lateral incisor (2.2) suffering from type III dens invaginatus with radicular cyst, in a 15-year-old patient. Discussion. When treating a dens invaginatus there are different therapeutic solutions: they depend on the gravity of the anomaly and on the association with the retention of a permanent tooth. The aesthetic and functional restoration becomes extremely important when performing a surgical-orthodontic repositioning.