How effective is the Invisalign® system in expansion movement with Ex30' aligners?

OBJECTIVES: The aims of this study are to validate a new method for quantifying the predictability of expansion movement with the Invisalign® system and to determine whether there are statistically significant differences between planned expansion with ClinCheck® and actual clinical quantification using upper post-treatment model comparisons. MATERIALS AND METHODS: A sample of 116 patients subjected to expansion with Invisalign® was studied. The following variables were measured at T1 and T2 on 3D models and ClinCheck®: canine gingival width, first premolar gingival width, second premolar gingival width, first molar gingival width, canine cuspid width, first premolar cuspid width, second premolar cuspid width, first molar cuspid width, canine depth, arch depth, first molar rotation, first right and left molar rotation, and first molar inclination. RESULTS: Measurement error was tested, showing good precision for all variables. The paired test showed non-significant differences between the 3D model and ClinCheck® at T1 for all variables except first molar cuspid width and arch depth. Statistically significant differences were found for canine gingival width, first premolar gingival width, second premolar gingival width, first molar gingival width, canine cuspid width, first premolar cuspid width, second premolar cuspid width, first molar cuspid width, and canine depth when the 3D model and ClinCheck® were compared at T2. CONCLUSIONS: Differences between the 3D model and ClinCheck® at T2 showed that planned expansion at the end of treatment is not predictable. CLINICAL RELEVANCE: This is the first in vivo human study to quantify the predictability of expansion in patients with Invisalign® Ex30 material.

Effectiveness of Biology-Based Methods for Inhibiting Orthodontic Tooth Movement. A Systematic Review.

INTRODUCTION: Several experimental studies in the literature have tested different biology-based methods for inhibiting or decreasing orthodontic tooth movement (OTM) in humans. This systematic review investigated the effects of these interventions on the rate of tooth movement. STUDY DESIGN: Electronic [MedLine; SCOPUS; Cochrane Library; OpenGrey;Web of Science] and manual searches were conducted up to January 26th, 2016 in order to identify publications of clinical trials that compared the decreasing or inhibiting effects of different biology-based methods over OTM in humans. A primary outcome (rate of OTM deceleration/inhibition) and a number of secondary outcomes were examined (clinical applicability, orthodontic force used, possible side effects). Two reviewers selected the studies complying with the eligibility criteria (PICO format) and assessed risk of bias [Cochrane Collaboration's tool]. Data collection and analysis were performed following the Cochrane recommendations. RESULTS: From the initial electronic search, 3726 articles were retrieved and 5 studies were finally included. Two types of biology-based techniques used to reduce the rate of OTM in humans were described: pharmacological and low-level laser therapy. In the first group, human Relaxin was compared to a placebo and administered orally. It was described as having no effect on the inhibition of OTM in humans after 32 days, while the drug tenoxicam, injected locally, inhibited the rate of OTM by up to 10% in humans after 42 days. In the second group, no statistically significant differences were reported, compared to placebo, for the rate of inhibition of OTM in humans after 90 days of observation when a 860 nm continuous wave GaAlA slow-level laser was used. CONCLUSIONS: The currently available data do not allow us to draw definitive conclusions about the use of various pharmacological substances and biology-based therapies in humans able to inhibit or decrease the OTM rate. There is an urgent need for more sound well-designed randomized clinical trials in the field.

Osteopontin gene SNPs (rs9138, rs11730582) mediate susceptibility to external root resorption in orthodontic patients.

OBJECTIVE: External apical root resorption (EARR) is a frequent iatrogenic effect of orthodontic treatment. Substantial variability in responses to postorthodontic EARR has been observed among patients even when similar treatment protocols were used. This observation suggests that environmental and/or genetic variations between individuals may confer susceptibility or resistance to developing EARR. The objective of this study is to determine whether variants in the osteopontin gene, an essential mediator in the odontoclast fusion and attachment process, are positively/negatively associated with postorthodontic EARR. MATERIALS AND METHODS: Genetic screening of eighty-seven orthodontic patients was performed for two polymorphisms in the osteopontin gene cluster (rs9138 and rs11730582). Subjects were divided into groups, according to the presence or absence of EARR (>2 mm). Genotype distributions and allelic frequencies were calculated using the chi-square test. Logistic regression analysis was used to assess the extent to which clinical-related parameters interfered with the EARR. Odds ratios (OR) and 95% confidence intervals were also calculated. RESULTS: Data from this study show that subjects heterozygous and homozygous for the most frequent allele of the osteopontin gene at position 89261521 [OR: 0.035 (P = 0.035*) (allele A)] and 89253600 [OR: 0.20 (P = 0.025*) (allele T)], respectively, are protected against postorthodontic EARR. Nevertheless, a highly significant association was found in the comparative analysis of homozygous subjects [2/2 (CC)] for the osteopontin gene (rs9138), resulting in an increased risk of suffering postorthodontic EARR[OR: 4.10; P = 0.045*; CI: 95%]. Subjects who were homozygous [2/2 (CC)] for the osteopontin gene (rs11730582) were more likely, and to a greater extent, to be affected with EARR [OR: 11.68; P < 0.039*; CI: 95%] compared with other genotypes. CONCLUSION: Variations in the osteopontin gene (rs9138 and rs11730582) are determinants of a genetic predisposition to suffer EARR secondary to orthodontic treatment.

A new three-dimensional analysis of asymmetry for patients with craniofacial syndromes.

OBJECIVES: The use of three-dimensional computed tomography (3D-CT) analyses represents a substantial improvement in planning treatment. The aim of this study is to introduce a new three-dimensional (3D) analysis of clinical value for evaluating asymmetry in cases of craniofacial syndrome. SUBJECTS AND METHODS: Virtual 3D models were reconstructed from CT images of 62 normal subjects (35 males and 27 females), more than 18 years old. Measurements of asymmetrical skeletal and dentoalveolar relationships were evaluated and standardized data obtained. The feasibility of the new 3D craniofacial analysis was then evaluated on one patient with severe maxillomandibular asymmetry in the form of hemifacial microsomia. RESULTS: Standardized 3D data from the analysis were obtained and classified into 6 maxillary measurements, eight mandibular measurements and seven dentoalveolar process measurements. No significant differences were found between males and females (U-Mann-Whitney test, P > 0.05). Useful data of clinical value was provided for planning orthodontic and surgical treatment of asymmetries, as well as a diagnostic chart. CONCLUSION: This method is useful for the clinical evaluation of asymmetry in craniofacial syndromes. The use of 3D analysis facilitates surgical and orthodontic treatment planning.

Association between craniofacial asymmetry and unilateral temporomandibular joint sounds in adult patients using 3D-computed tomography.

OBJECTIVES: The purpose of this study was to investigate the possible relationship between unilateral temporomandibular joint (TMJ) sounds and craniofacial asymmetry, using 3D-computed tomography (CT) measurements. SUBJECTS AND METHODS: Forty-one reconstructed 3D-CT models of adult subjects were measured to analyze craniofacial asymmetry. Subjects were divided into two groups depending on the presence (n = 20) or absence (n = 21) of unilateral joint sounds, and the results compared using the Mann-Whitney U-test. To investigate the association between these parameters, the Pearson correlation coefficient was calculated. RESULTS: Asymmetries in the maxillary and mandibular structures were statistically significant (P < 0.05) for subjects with unilateral TMJ sounds and for controls, except in the case of maxillary rotation and mandibular ramus height (P > 0.05). The highest deviations found were frontal and lateral ramal inclination, goniac angle and canting of occlusal plane. CONCLUSIONS: Adult patients with unilateral joint sounds may have skeletal jaw asymmetry and a canted occlusal plane.

Do the smiles of the world's most influential individuals have common parameters?

The aim of this study was to determine - on the basis of the most recent yearly listings - whether there were any common measurable variables associated with the smiles of the world's most influential people. A total of 168 subjects were selected from the lists of Time magazine's 100 most influential people during the period 2006-2010. Smiling frontal view photographs were obtained. Thirty-six variables for each subject were traced and measured using photogrammetric analysis to obtain qualitative and quantitative proportions and measurements. Differences with respect to gender, occupation and year of listing were tested to 95% significance, using the Student's t-test and the Kruskal-Wallis test. The chi-squared test was used for qualitative variables. Irrespective of gender or occupation, the similar quantifiable characteristics of the smiles of the most influential subjects were the following: vertical upper lip proportion, smile width, incisor exposure, buccal corridor ratio, smile symmetry index and intra-dental proportions (P > 0·05). Other qualitative standards were as follows: smile symmetry, the buccal corridors and smile arc, direction of occlusal cant and the degree of deviation between maxillary and facial midlines. Differences were found for gingival display and smile height parameters (P = 0·001). The smiles of the world's most influential people revealed common standards, regardless of occupation or gender, which may play a decisive role in the expressions of influential faces.

Postorthodontic external root resorption is associated with IL1 receptor antagonist gene variations.

OBJECTIVE: External apical root resorption (EARR) is a frequent iatrogenic effect of orthodontic treatment. Patients with genetic variants in the interleukin 1 gene have been related to an increased risk of suffering EARR. The objective of this study is to determine whether variants in the interleukin 1 receptor antagonist gene are positively/negatively associated with interleukin 1 gene polymorphisms, particularly in relation to the clinical features of EARR patients. MATERIALS AND METHODS: Genetic screening of 54 orthodontic patients was performed for three polymorphisms (rs1800587, rs1143634 and rs419598) in the IL1 gene cluster. Subjects were divided according to the presence or absence of EARR of more than 2 mm. The genotype distributions and allelic frequencies were calculated by the chi-square-test. Odds ratios (OR) and 95% confidence intervals were also calculated. RESULTS: A highly significant association was found in the comparative analysis of homozygous subjects [1/1(CC)] for the IL1B gene, resulting in an increased risk of suffering postorthodontic EARR (OR: 3.47; P = 0.027; CI: 95%). While no association was found for the IL1A gene (P = 0.097), subjects who were homozygous [1/1(TT)] for the IL1RN gene were more likely to be affected with EARR (OR: 6.75; P = 0.001; CI: 95%). CONCLUSION: Variations in the interleukin 1 receptor antagonist gene (rs419598) - and not only in the IL1B gene (rs1800587) - are determinants of a predisposition to postorthodontic EARR.

Retrospective long-term evaluation of autotransplantation of premolars to the central incisor region.

AIM: This retrospective case-series study aimed to examine the long-term outcomes of autogenously transplanted premolars. METHODOLOGY: Twelve patients in whom donor premolars were used to replace maxillary central incisors lost by trauma were clinically and radiologically monitored. Standardized clinical and radiographic records were systematically obtained during the follow-up period of 14 years, to determine the influence of specific clinical criteria on the overall success rate of transplantation. RESULTS: The success rate of premolar autotransplantation in the maxillary central incisor area was 80% after 14 years follow-up. The highest success rate occurred in those teeth transplanted with two-thirds of full root development. Complete pulp obliteration was positively related to autotransplant viability, followed by root formation in the bony crypt. CONCLUSIONS: Autotransplantation of donor teeth, at the stage of ½ to ¾ of their expected root length, can provide a successful treatment solution for over 14 years.

Interleukin 1 gene cluster SNPs (rs1800587, rs1143634) influences post-orthodontic root resorption in endodontic and their contralateral vital control teeth differently.

AIM: To investigate whether the genetic variants of the interleukin-1 gene cluster (IL1) are associated with a possible genetically induced variability in post-orthodontic external apical root resorption (EARR) in root filled teeth and their control counterparts with vital pulps. METHODOLOGY: One hundred and forty-six maxillary premolars were evaluated radiographically following orthodontic treatment. Genetic screening was performed on orthodontic patients for two single-nucleotide polymorphisms (SNPs: rs1800587 and rs1143634) in the IL1 gene cluster. Subjects were divided into two groups according to the presence or absence of radiographic post-orthodontic EARR (>2 mm) in root filled teeth and their controls with vital pulps. Logistic regression analysis was performed to obtain an adjusted estimation between EARR and IL1 polymorphisms. Allelic frequencies, genotype distributions, and adjusted odds ratio (OR), at 95% confidence interval, were also calculated. RESULTS: Whilst no clear statistical association was found for gene variations in IL1A, a sound association was found in the comparative analysis of subjects homozygous [2/2(TT)] for the IL1B gene, which resulted in a two times increased risk of suffering post-orthodontic EARR in root filled teeth [OR, 2.032 (P = 0.031); CI,1.99-14.77] when compared with their controls with vital pulps. There was, however, a shared predisposition to EARR in controls with vital pulps and root filled teeth of subjects homozygous for allele 1 [OR, 5.05 (P = 0.002)] and [OR, 2.77 (P = 0.037)], respectively. CONCLUSIONS: Genetic variations in the interleukin-1ß gene (rs1143634) predispose root filled teeth to EARR for matched pairs secondary to orthodontic treatment in a different way from their control teeth with vital pulps in subjects homozygous for allele 2 [2/2(TT)].

Maxillary protraction at early ages. The revolution of new bone anchorage appliances.

PURPOSE: An update is provided on the different types of early treatment for class III malocclusions of maxillary origin. There is an increasing tendency to prescribe maxillary orthopedic treatment with skeletal anchorage, with the purpose of enhancing the skeletal and reducing the dentoalveolar effects--offering a management option for children with important deformations that otherwise would have to wait until adult age to receive surgical treatment. METHOD: A literature review has been made of maxillary bone orthopedic traction appliances in growing children with class III malocclusions. A Medline (PubMed) search was made using the following MeSH terms: Cephalometric, Child, Malocclusion class III/therapy, Extraoral traction appliances, Palatal expansion, Bone plates, Skeletal anchorage, Orthodontic anchorage. RESULTS: Many articles show that the greatest maxillary advances are obtained at very early ages, though with a greater tendency towards relapse. However skeletal anchorage has been seen to afford a lesser relapse rate and greater dentofacial orthopedic efficiency due to its low dentoalveolar impact. In any case, further randomized clinical studies are needed to firmly establish the quantifiable differences in terms of maxillary advance, optimum traction age, optimum traction appliance and potential side effects. At present, the incorporation of surgically inserted bone anchorage appliances (miniplates and miniscrews) offers a purely orthopedic approach to treatment, with minimization of the undesirable side effects of traditional dentofacial orthopedic compensation based on dentoalveolar anchorage. Nevertheless, further studies are needed to consolidate the supporting scientific evidence in this field.

The use of gene therapy vs. corticotomy surgery in accelerating orthodontic tooth movement.

OBJECTIVE: Alveolar corticotomy surgery is an adjunctive therapy for reducing orthodontic treatment duration. The activation pathways of bone resorption involved in the tooth movement (TM) process are directly linked to the receptor activator of the nuclear factor-kB ligand (RANKL). Whether similar molecular pathways through RANKL, are shared by the acceleratory TM process (corticotomy-induced or not), sustained acceleration would therefore be expected with transgenic overexpression of this factor. We hypothesize that maintaining transgenic overexpression of RANKL will accelerate TM under force over time rather than at the beginning of therapy only; this contrasts with the corticotomy procedure. MATERIAL AND METHODS: We transfected the pcDNA3.1(+)-mRANKL transgene in vitro into NIH3T3 cells, then evaluated by PCR, Western blot and ex vivo resorption assay. Quantification of RANKL immunofluorescence, fluorescence-based tartrate-resistant acid phosphatase+ (TRAP+) osteoclast counts and histological analyses of the bone resorption area were performed and clinically correlated after a 32-day in vivo experiment comparing corticotomy and gene therapy. RESULTS: In vitro experiments resulted in increased level of RANKL protein (46%, p<0.05) and greater mineral resorption (39%, p<0.05) compared to the controls. In vivo results showed increased RANKL immunoexpression for both corticotomy (twofold) and transfection groups (threefold) after 10 days. After 32 days, a similar result was obtained for the transfected group but not for the surgery group. These data correlate with the clinical effect of decelerating TM in the surgery group. CONCLUSIONS: Selective gene therapy with RANKL has been experimentally tested as an alternative method to corticotomy surgery, showing higher effectiveness than surgical methods used for acceleratory purposes in orthodontics.

Treatment of an avulsed maxillary permanent central incisor replaced by autotransplantation of a mandibular premolar: 14-year follow-up.

AIM: To present the 14 year follow-up of a case in which an avulsed permanent maxillary central incisor was replaced by autotransplantation of a mandibular premolar. SUMMARY: A mandibular premolar (Moorrees' stage 3) was transplanted into the space left by an avulsed permanent maxillary central incisor after a delay of 3 months. Recall examination 14 years after transplantation revealed a normal periodontal architecture with absence of infection, ankylosis or progressive resorption. The transplantation of a premolar is seen as a promising method to replace a lost permanent tooth and to restore aesthetics and function. KEY LEARNING POINTS: * Autotransplantation is a viable option for the treatment of a missing tooth or for replacement of avulsed and traumatized tooth when a donor tooth is available. * Autotransplantation is a therapeutic option for the substitution of missing anterior teeth in young patients who also need orthodontic treatment.

Vertical and Transverse Management with Transpalatal Arches in an Adult with Class III Malocclusion.

The transpalatal arch might be one of the most common intraoral auxiliary fixed appliances used in orthodontics in order to provide dental anchorage. The aim of the present case report is to describe a case in which an adult patient with a tendency to class III, palatal compression, and bilateral posterior crossbite was treated with double transpalatal bars in order to control the torque of both the first and the second molars. Double transpalatal arches on both first and second maxillary molars are a successful appliance in order to control the posterior sectors and improve the torsion of the molars. They allow the professional to gain overbite instead of losing it as may happen with other techniques and avoid enlarging of Wilson curve, obtaining a more stable occlusion without the need for extra help from bone anchorage.

Current concepts on the effect of environmental factors on cleft lip and palate.

The aim of this study was to investigate the effect of environmental factors, such as tobacco, alcohol and folic acid intake, obesity, stressful events, low blood levels of zinc and fever during pregnancy, on the incidence of cleft lip and/or palate (CL±P). An electronic search was performed in the Cochrane Reviews, the ISI Web of Knowledge, PubMed and Scopus, along with a manual search to identify other relevant case-control and cohort studies. Quality assessments and an evaluation of publication bias were undertaken. Statistical heterogeneity was examined, and odds ratios (ORs) and 95% confidence intervals (CI) estimated using the random effects model. Of 372 articles initially retrieved, 28 studies were selected as eligible for meta-analysis. No evidence of publication bias was found using funnel plot analysis and the Egger linear regression method. Many studies were classified as low quality due to inadequate case-control data. On the basis of this research, maternal factors most associated with CL±P were: tobacco (OR 1.48), alcohol (OR 1.28), folic acid intake (OR 0.77), obesity (OR 1.26), stressful events (OR 1.41), low blood zinc levels (OR 1.82), and fever during pregnancy (OR 1.30). Folic acid intake by the mother reduced the risk of CL±P in offspring (OR 0.77).

[Elastic activator appliances: Bimler's elastic appliance and Klammt's elastic activator]. / Activateurs élastiques: modeleur élastique de BIMLER et activateur élastique de KLAMMT.

The action of two elastic activators (Bimler and Klammt) is studied in twenty Class II/1 malocclusions, with a mean age of 10.2 years and a treatment time of 2.7 years. Intercanine and intermolar widths, and "anterior arch height" (Korkhaus) were measured on models at the beginning and at the end of treatment. On lateral X-Ray films following parameters (Ricketts) were measured: facial axis, facial depth, convexity, lower facial height, and corpus axis. Conclusions are: both appliances have a good transverse response, Bimler's Gebissformer increase vertical growth, and Klammt's elastic activator decrease convexity by a more anterior mandibular positioning.

[Transversal problems]. / Problemas transversales.

In this worn we introduce the alterations of the occlusion in the horizontal level or transversal problems, in which lateral crossed bites appear, either with or without a deviation of the medium line, underlying its differential diagnostic and guide lines treatment through several different clinic cases.