Biomechanics in Orthodontics Research Papers (original) (raw)

As we see more adults entering comprehensive orthodontic treatment, we must be more attuned to the implications of periodontal issues. In this updated chapter, Robert Vanarsdall, Ignacio Blasi and Antonino Secchi review periodontal issues that impact orthodontic tooth movement. They describe periodontal "high risk" factors, mucogingival considerations, and problems with ectopic as well as ankylosed teeth. A new section on alveolar decortication and augmentation grafting has been added to address the increased use of these procedures designed to develop the alveolar housing and potentially increase the speed of tooth movement. Excellent clinical examples are pictured throughout the chapter.

- by and +1
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- Orthodontics, Periodontics, Periodontology, Biomechanics in Orthodontics
- by muhamad abu-hussein
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- Dental Research, Case Study Research, Dental Anthropology, Dental Health

Background: The malocclusion indices have been used routinely by researchers to gather data regarding the prevalence of orthodontic treatment needs and trait. The scoring methods of malocclusal indices can be used to generate data regarding the actual load of the malocclusion which can be used for resource and fund allocation and identify the actual orthodontic treatment needs. This article will provide an insight to the various orthodontic indices and its specific indications.

In orthodontic practice various treatment modalities have been
presented for the treatment for the class II, div 1malocclusions.
Recently a large number of young adults have been seeking
shorter, cost effective and a non surgical correction of Class II
malocclusions and they accept dental camouflage as a treatment option to mask the skeletal discrepancy .This case report presents one such case, a 15years old growing male who has Class II div I malocclusion with sever maxillary incisor proclination, convex profile ,high mandibular plane angle, incompetent lips, increased overjet& overbite, over retained upper left deciduous canine ,impacted upper left canine and a supernumerary tooth in canine region. We considered the camouflage treatment by extracting the upper right first premolar, left impacted canine, deciduous canine
and supernumerary tooth. Following the treatment, a satisfactory result was achieved with an ideal, static and a functional occlusion, facial profile, acceptable smile, competent lip and stable treatment results.

The terminology “serial extraction” in Orthodontics was first described in the late 1920’s when Kjellgren [1] decided to plan the extraction of certain deciduous and permanent teeth at early stages of the dentition development. Since the extractions are under taken at the transitional dentition. This type of treatment is defined as “Early Treatment” in Orthodontics [2]. The main indication for this treatment approach is for patients with severe crowding caused by tooth size arch discrepancies [3,4]. In other words, when maxillary and/or mandibular arches cannot accommodate teeth, extraction becomes an interesting option. Although this treatment option has been used for almost a century in the contemporary orthodontics it’s indication is very specific. Since it’s an irreversible approach (permanent teeth are early extracted) the clinician should carefully diagnosis the case before selecting this option. In addition, as time passed by, orthodontics specialty has dramatically evolved and developed several options to gain space instead of extracting teeth. On the other hand, the idea to early extract permanent teeth continues to be an interesting treatment option in clinical orthodontics mainly in severely crowded patients. The aim of this paper is to present a case report of a ten-year-old male patient who presented severe crowding and treatment option was to extract four first premolars at early stages of the dentition development.

text book of orthodontics

- by Aldany Aldany
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- Biomechanics in Orthodontics
- by Ignacio Blasi and +1
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- Orthodontics, Biomechanics in Orthodontics, Aesthetics in Orthodontics, Orthodontic Research

Minimally and Non-Invasive Approaches to Accelerate Tooth Movement:
Micro-osteoperforations. Patients are always attracted to decreasing the time it takes to complete orthodontic treatment. Recent advances in the understating of bone biology have been applied to a number of adjunctive techniques that in certain situations may reduce the time for certain tooth movements. In this new chapter, Ignacio Blasi looks at the use of micro-osteoperforations and the ability of these perforations to increase bone turnover rates, providing for increased speed of tooth movement. Studies have been done that demonstrate a localized positive effect on the speed of tooth movement.
Mechanical Vibration. Dubravko Pavlin presents information on the influence of low level mechanical vibration on orthodontic treatment, a technique borrowed from orthopedic colleagues. Some of the animal and human studies have reported increased rates of tooth movement and an ability to reduce pain perception when low level vibration therapy is used. Still other studies report no clinical effectiveness. While the jury is still out on this technique, clinical and basic science research into adjuncts that can influence biologic factors, are likely to bear fruit in the future.

- by Ignacio Blasi and +1
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- Orthodontics, Periodontics, Combined Orthodontic-Surgical Treatment, Orthodontist

Pour assurer au mieux les mouvements orthodontiques,
l’orthodontie a besoin de s’appuyer sur un ancrage fiable,
le plus fixe possible. Dans de nombreux cas, l’ancrage
intra-buccal ou même extra-buccal ne peut répondre aux
exigences d’ancrage du praticien orthodontiste. En assurant
un ancrage fixe, l’ancrage squelettique permet la mise
en oeuvre de mouvements complexes tels que ingressions
ou déplacements d’un groupe de dents. Cet article décrit
l’ancrage squelettique, son développement historique, ses
différentes applications, les paramètres à considérer, ses
avantages puis ses limitations. Un cas clinique est présenté
afin de montrer les différentes étapes du traitement ainsi
que le résultat obtenu. Orthodontistes et impantologistes
ont là une occasion de collaborer plus étroitement que par
le passé. Cette interaction devrait permettre des traitements
et des résultats considérés jusque-là comme impossibles à
mener et à obtenir.

- by Paul M Khoury
- •
- Dentistry, Restorative Dentistry And Endodontics, Dental Research, Dental Materials

Effect of long-term orthodontic treatment on salivary nickel and chromium has not been quite assessed except in few retrospective studies with controversial results. The aim of this prospective study was to measure salivary levels of these ions during 1 year of orthodontic treatment. Saliva samples were collected from 20 orthodontic patients, before treatment (control) and 6 and 12 months later. Nickel and chromium concentrations were determined using atomic absorption spectrophotometry. Data were analyzed using one- and two-way repeated-measures ANOVA, Bonferroni, Friedman (α = 0.05), and Wilcoxon signed-ranks tests (α = 0.016). Average nickel level changed from 9.75 ± 5.02 to 10.37 ± 6.94 and then to 8.32 ± 4.36 μg/L in 1 year. Average chromium concentration changed from 3.86 ± 1.34 to 4.6 ± 6.11 and then to 2.04 ± 1.66 μg/L. Alterations in nickel values were not statistically significant [P = 0.468 (ANOVA)], but fluctuations in chromium levels were [P = 0.021 (Friedman)]. The dec...

- by fariborz amini
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- Dentistry, Biotechnology, Heavy metal monitoring and analysis, Adolescent

Papageorgiou SN, G€ olz L, Jäger A, Eliades T, Bourauel C. Lingual vs. labial fixed orthodontic appliances: systematic review and meta-analysis of treatment effects. Eur J Oral Sci 2016; 00: 000–000. © 2016 Eur J Oral Sci The aim of this systematic review was to compare the therapeutic and adverse effects of lingual and labial orthodontic fixed appliances from clinical trials on human patients in an evidence-based manner. Randomized and prospective non-randomized clinical trials comparing lingual and labial appliances were included. Risk of bias within and across studies was assessed using the Cochrane tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random-effects meta-analyses were conducted, followed by subgroup and sensitivity analyses. Six electronic databases were searched from inception to July 2015, without limitations. A total of 13 papers pertaining to 11 clinical trials were included with a total of 407 (34% male/66% female) patients. Compared with labial appliances, lingual appliances were associated with increased overall oral discomfort , increased speech impediment (measured using auditory analysis), worse speech performance assessed by laypersons, increased eating difficulty, and decreased intermolar width. On the other hand, lingual appliances were associated with increased intercanine width and significantly decreased anchorage loss of the maxillary first molar during space closure. Based on existing trials, there is insufficient evidence to make robust recommendations for lingual fixed orthodontic appliances regarding their therapeutic or adverse effects, as the quality of evidence was low.

Background: Although the headgear appliance has been used extensively to correct anteroposterior discrepancies, its treatment effects have not yet been adequately assessed in an evidence-based manner. Objective: Aim of this systematic review was to assess the therapeutic and adverse effects of early headgear treatment from controlled clinical trials on human patients in an evidence-based manner. Search methods: An unrestricted electronic search of six databases from inception to December 2015. Selection criteria: Randomized and prospective non-randomized controlled trials assessing the effects of headgear treatment on human patients. Data collection and analysis: After duplicate study selection, data extraction, and risk of bias assessment according to the Cochrane guidelines, random-effects meta-analyses of mean differences (MDs) and relative risks (RRs), including their 95% confidence intervals (CIs) were performed, followed by subgroup and sensitivity analyses. Results: A total of 18 unique studies with a total of 930 (56% male/44% female) patients were included. Headgear treatment was associated with a posterior translation of the anterior maxilla border in the short term, as seen by the mean annualized change in the SNA angle (MD = −1.63°/ year; 95% CI = −2.20 to −1.06°/year; high quality evidence) compared to untreated patients. This effect was independent of the rotation of the palatal plane and the inclination of the upper incisors, while a proportional relationship with the initial discrepancy in SNA was seen. The clinical significance of this improvement diminished in the long term, although only limited evidence existed. Additionally, early headgear treatment might decrease the risk of dental trauma during the following years (RR = 0.34; 95% CI = 0.14 to 0.80; moderate quality evidence). Low quality evidence on the effect of headgear on the rotation of the palatal plane, the nasolabial angle, the occlusal outcome, and signs of temporomandibular disorders precluded robust assessments, due to risk of bias, inconsistency, imprecision, and small-study effects. Conclusions: Based on existing trials, headgear is a viable treatment option to modify sagittal growth of the maxilla in the short term in Class II patients with maxillary prognathism. Registration: PROSPERO (CRD42015029837). Funding: None.

- by Spyridon Papageorgiou
- •
- Orthodontics, Clinical Trials, Clinical Trial, Meta-Analysis (Statistics)

Background: Permanent canines are amongst the teeth most affected by impaction and ectopic eruption. Although impacted canines are often subjected to surgical exposure and alignment with either the open or the closed technique for many decades, their treatment effects have not yet been systematically asssessed. Objectives: The aim of this systematic review was to critically assess whether significant differences exist in the outcomes of the open or closed surgical exposure of impacted canines. Search methods: An unrestricted electronic search of nine databases from inception to December 2016 was performed. Selection criteria methods: Included were randomized or prospective non-randomized studies comparing open versus closed exposure of impacted canines in human patients. Data collection and analysis: After duplicate study selection, data extraction, and risk of bias assessment according to the Cochrane guidelines, random-effects meta-analyses of mean differences (MDs) and odds ratios (ORs), including their 95 per cent confidence intervals (CIs) were performed, followed by subgroup and sensitivity analyses. Results: A total of eight unique studies and a total of 433 (30.1% male/59.9% female) patients were included, with an average age of 15.2 years and a total of 453 impacted canines (48.6% and 51.4% in the open and closed exposure, respectively). Open exposure of impacted canines was associated with reduced duration of canine alignment (two studies; MD = –2.14 months; 95% CI = –4.23 to –0.05 months; P < 0.05; moderate heterogeneity and moderate quality) and lower odds of tooth ankylosis (one study; OR = 0.15; 95% CI = 0.03–0.83; P < 0.05; low quality) compared to closed exposure; both findings being independent of canine localization. However, initial alignment of palatally impacted canines took overall significantly longer than labially impacted canines (8.87 versus 4.17 months). Conclusions: Based on existing evidence, open surgical exposure seems to be superior in treatment duration and ankylosis risk over the closed technique. Due to the limited number of small included trials, further research is needed for robust clinical recommendations. Registration: PROSPERO (CRD42016051916).

Abstract
Purpose Although several prescriptions and techniques exist for comprehensive fixed appliance treatment, their treatment effects have not yet been adequately assessed in an evidence-based manner. The aim of this systematic review was to assess the therapeutic and adverse effects of various prescriptions or techniques for orthodontic appliances from randomized clinical trials on human patients.
Methods Eight databases were searched up to July 2016 for randomized trials assessing any orthodontic prescriptions or techniques in human patients. After elimination of duplicate studies, data extraction, and risk of bias assessment according to the Cochrane guidelines, random effects meta-analyses with mean differences (MD) and their 95% confidence intervals (CIs) were performed.
Results Compared to Roth preadjusted appliances, both Begg and modified Begg appliances were associated with statistically significantly worse occlusal outcome assessed with Peer Assessment Review (PAR) scores (1 trial, MD 3.1 points, 95% CI 1.9–4.3 points and 1 trial, MD 2.4 points, 95% CI 1.2–3.6 points, respectively) with low quality of evidence, due to bias and imprecision. Compared to a partially programmed fixed orthodontic appliance, a fully programmed appliance was associated with a statistically significant, but clinically irrelevant increase in treatment duration (1 trial, MD 2.4 months, 95% CI 0.6–4.2 months), supported by high quality of evidence. However, caution is needed in the interpretation of these results as only a limited number of small trials with methodological issues were available.
Conclusions Based on existing trials, there is limited evidence to support any robust clinical recommendation
regarding the prescriptions or techniques for fixed orthodontic appliances.
Registration: PROSPERO (CRD42016042727).
Funding: None.

Review Soft tissue changes following extraction vs. nonextraction orthodontic fixed appliance treatment: a systematic review and meta-analysis Konstantonis D, Vasileiou D, Papageorgiou SN, Eliades T. Soft tissue changes following extraction vs. nonextraction orthodontic fixed appliance treatment: a systematic review and meta-analysis. Eur J Oral Sci 2018; 00: 1–13. © 2018 Eur J Oral Sci The aim of this systematic review was to assess the effect of systematic extraction protocols during orthodontic fixed appliance treatment on the soft tissue profile of human patients. Nine databases were searched until December 2016 for controlled clinical studies including premolar extraction or nonextraction treatment. After elimination of duplicate studies, data extraction, and risk-of-bias assessment according to the Cochrane guidelines, random-effects meta-analyses of mean differences (MD) or standardized mean differences (SMD) and their 95% CIs were performed, followed by subgroup, meta-regression, and sensitivity analyses. Extraction treatment was associated with increased lower lip retraction (24 studies; 1,456 patients; MD = 1.96 mm), upper lip retraction (21 studies; 1,149 patients; MD = 1.26 mm), nasolabial angle (21 studies; 1,089 patients; MD = 4.21°), soft-tissue profile convex-ity (six studies; 408 patients; MD = 1.24°), and profile pleasantness (three studies; 249 patients; SMD = 0.41). Patient age, extraction protocol, and amount of upper incisor retraction during treatment were significantly associated with the observed extraction effects, while the quality of evidence was very low in all cases due to risk of bias, baseline confounding, inconsistency, and imprecision. Although tooth extractions seem to affect patient profile, existing studies are heterogenous and no consistent predictions of profile response can be made.

Objectives Aim of this systematic review was to assess the effect of orthodontic treatment with fixed appliances on the tooth color of patients. Methods Nine databases were searched up to May 2017 for clinical cohort studies on the effect of fixed appliance treatment on tooth color. After elimination of duplicate studies, data extraction, and risk of bias assessment according to the Cochrane guidelines, random effects meta-analyses of mean differences (MD) or means and their 95% confidence intervals (CIs) were performed, followed by GRADE (Grading of Recommendations Assessment, Development and Evaluation) assessment of the quality of evidence. Results Three nonrandomized and one randomized study with a total of 138 patients (46% male, 54% female) with average age of 15.7 years were included. Tooth color of treated patients was significantly altered during or after orthodontic treatment (4 studies; average of 3.2 E units; 95% CI = 2.0–4.4 E units), which was more than the variation among controls (1 study; MD = 1.9 E units; 95% CI = 1.7–2.2 E units). However, the quality of evidence was very low, due to the inclusion of nonrandomized studies, bias, and imprecision. Re-analysis of raw study data indicated that significant differences in clinically discernable treatment-induced color changes were seen between chemically and light-cured adhesives and among the various tooth categories. Conclusion Existing evidence of very low quality indicates that orthodontic treatment might be associated with alterations of tooth color, which are however not consistently clinically discernible. Treatment-induced color alterations might be dependent on bonding material and tooth type, but evidence supporting this is weak.

- by Spyridon Papageorgiou
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- Orthodontics, Dental Research, Meta-Analysis (Statistics), Bone and tooth
- by Daniela Feu
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- Biomechanics in Orthodontics

Aim: To assess the effectiveness of zygomatic anchorage for the intrusion of maxillary pos- terior teeth. Method: A male patient, 20 years 5 months of age, with 3-mm anterior open bite with excessive maxillary posterior growth, was accepted for treatment. Titanium mini- plates were fixed bilaterally to the zygomatic buttress area and 200 g of force was applied unilaterally with 9-mm nickel-titanium coil springs between the vertical extension of the miniplate and the first molar buccal tube. Later, the zygomatic site was used for maxillary canine distalization. Results: The maxillary posterior teeth were intruded effectively and the canines were distalized bodily, without anchorage loss, with the help of zygomatic anchor- age. The patient was advised to maintain good oral hygiene throughout the treatment. This noninvasive surgical procedure eased and reduced the operation time and did not require headgear wear nor anterior box elastics for anterior open bite correction. Conclusion: The zygomatic area was found to be a useful anchorage site for the intrusion of the molars over a short period of time. Long-term stability of the bite closure should be assessed in future studies. World J Orthod 2002;3:147–153.

Introduction: Aim of this study was to assess the registration of orthodontic systematic reviews in PROSPERO. Method: Seven databases were searched for orthodontic systematic reviews published in 2012-2016. After duplicate study selection and data extraction, descriptive statistics, followed by chi-square/Fisher exact tests were calculated. Finally, bivariable/multivariable regression with relative risks (RR) and 95% confidence intervals (CIs) was used. Results: A total of 182 orthodontic systematic reviews were identified, 37 (20.3%) of which were registered in PROSPERO, with registration rates ranging from 4.3% in 2012 to 37.0% in 2016. Differences in review registration were found according to publication year, geographic origin, multicentre status, funding, and journal category. After controlling for confounders, each additional year was associated with increased registration probability (RR = 1.51; 95% CI = 1.19– 1.93). Reviews from South America were more likely to be registered than reviews from Europe (RR = 1.49; 95% CI = 1.06–2.11). Finally, reviews published in orthodontic specialty journals were more likely to be registered than reviews in general dentistry journals (RR = 1.87; 95% CI = 1.02– 3.49). Conclusions: A small percentage of orthodontic systematic reviews was registered a priori, although improvement signs have been seen since the initiation of PROSPERO.

ABSTRACT
Objective: There is an increasing tendency to prescribe maxillary orthopaedic treatment with skeletal anchorage, with the goal of enhancing the skeletal and minimizing the dentoalveolar effects – offering a management option for skeletal Class III dysmorphoses that otherwise they received surgical treatment in their adulthood. An update is provided to evaluate the effects on maxilla, mandible, dentoalveolar part, soft-tissue and airway of intra-oral skeletally anchored maxillary protraction (I-SAMP) for correction of skeletal Class III malocclusion. Method: A literature review has been made to consolidate the supporting scientific evidence in this field of Intra-oral skeletally anchored maxillary protraction (I-SAMP) in growing children having Class III malocclusion. A Medline (PubMed) search was made using the following MeSH terms: Malocclusion Class III therapy, Intraoral traction appliances, Bone plates, Skeletal anchorage, Maxillary protraction. Results: At present, many articles show that the incorporation of surgically inserted bone anchorage appliances (miniplates and miniscrews) has been seen to afford a lesser relapse rate and greater dentofacial orthopaedic correction due to its lesser dentoalveolar impact. Nevertheless, further randomized clinical studies are needed to firmly establish the quantifiable differences in terms of maxillary advance, mandible and TMJ effects, optimum traction appliance, optimum traction chronological age, and potential side effects.

Background: Although Rapid Maxillary Expansion (RME) has been used for over a century, its effect on upper airways has not yet adequately been assessed in an evidence-based manner. Objective: To investigate the volumetric changes in the upper airway spaces following RME in growing subjects by means of acoustic rhinometry, three-dimensional radiography and digital photogrammetry. Search methods: Literature search of electronic databases and additional manual searches up to February 2016. Selection criteria: Randomized clinical trials, prospective or retrospective controlled clinical trials and cohort clinical studies of at least eight patients, where the RME appliance was left in place for retention, and a maximum follow-up of 8 months post-expansion. Data collection and analysis: After duplicate data extraction and assessment of the risk of bias, the mean differences and 95 per cent confidence intervals (CIs) of upper airway volume changes were calculated with random-effects meta-analyses, followed by subgroup analyses, meta-regressions, and sensitivity analyses. Results: Twenty studies were eligible for qualitative synthesis, of which 17 (3 controlled clinical studies and 14 cohort studies) were used in quantitative analysis. As far as total airway volume is concerned patients treated with RME showed a significant increase post-expansion (5 studies; increase from baseline: 1218.3 mm 3 ; 95 per cent CI: 702.0 to 1734.6 mm 3), which did not seem to considerably diminish after the retention period (11 studies; increase from baseline: 1143.9 mm 3 ; 95 per cent CI: 696.9 to 1590.9 mm 3). Limitations: However, the overall quality of evidence was judged as very low, due to methodological limitations of the included studies, absence of untreated control groups, and inconsistency among studies. Conclusions: RME seems to be associated with an increase in the nasal cavity volume in the short and in the long term. However, additional well-conducted prospective controlled clinical studies are needed to confirm the present findings.

Aim: The validity of meta-analysis is dependent upon the quality of included studies. Here, we investigated whether the design of untreated control groups (i.e. source and timing of data collection) influences the results of clinical trials in orthodontic research. Materials and methods: This meta-epidemiological study used unrestricted literature searching for meta-analyses in orthodontics including clinical trials with untreated control groups. Differences in standardized mean differences (ΔSMD) and their 95% confidence intervals (CIs) were calculated according to the untreated control group through multivariable random-effects meta-regression controlling for nature of the interventional group and study sample size. Effects were pooled with random-effects synthesis, followed by mixed-effect subgroup and sensitivity analyses. Results: Studies with historical control groups reported deflated treatment effects compared to studies with concurrent control groups (13 meta-analyses; ΔSMD = −0.31; 95% CI = −0.53, −0.10; P = 0.004). Significant differences were found according to the type of historical control group (based either on growth study or clinical archive; 11 meta-analyses; ΔSMD = 0.40; 95% CI = 0.21, 0.59; P < 0.001). Conclusions: The use of historical control groups in orthodontic clinical research was associated with deflation of treatment effects, which was independent from whether the interventional group was prospective or retrospective and from the study's sample size. Caution is warranted when interpreting clinical studies with historical untreated control groups or when interpreting systematic reviews that include such studies.

- by Vasiliki Koretsi and +1
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- Orthodontics, Meta-Analysis (Statistics), Meta-Analysis and Systematic Review, Meta-analysis (Social Sciences)

Introduction: Self-ligating brackets are the last technological innovation in orthodontics. Many advantages have
been said they have over the conventional brackets.
Development: Friction is the resistive force between one
object against another one during perpendicular motion.
Together with binding and notching, friction is responsible for the sliding resistance observed in orthodontics
through out alignment, level and space closure stages.
Dental arch expansion from low forces, treatment time
and the comparison to traditional brackets were considered
a benefit as well as periodontal indexes and produced white
spots. Patient’s discomfort was taken into consideration
during orthodontic treatment with both types of brackets
and the save of time.
Conclusions: Except for this last factor during the arch
insertion and adjustment, there are no advantages based
on present evidence between self-ligating and conventional brackets.

- by Daniel Segovia
- •
- Orthodontics, Biomechanics in Orthodontics, Dentistry and Orthodontics, Ortodoncia

Sliding mechanics is widely used today for space closure in orthodontics. It presents a series of advantages that found its popularity according to experts. It is divided into two types; individual and in-mass. The objective of this work... more

- by Daniel Segovia
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- Orthodontics, Biomechanics in Orthodontics, Ortodoncia
- by Ione Brunharo
- •
- Dentistry, Biomedical Engineering, Treatment Outcome, Biomechanics in Orthodontics

Extraction of premolar teeth to manage class I malocclusion is
conventionally the management approach of choices. However
class I malocclusion with tooth tissue discrepancy could be manage
with the extraction of a lower incisor tooth with a more acceptable
aesthetic outcome. This article describe a cases of class I
malocclusion mange with extracting a mandibular lower incisor
tooth

- by Md. Nazmul Hasan
- •
- Dentistry, Orthodontics, Biomechanics in Orthodontics, Orthodontic Research

Rapid palatal expansion (RPE) has been used primarily to treat dental crossbites or for space gaining to prevent extractions with little or no attempt made to coordinate or normalize the transverse skeletal pattern. Traditionally, maxillary orthopedics has been performed using the dental units only as anchorage (e.g., Hyrax or Haas appliances). Dental anchorage not only has created limited skeletal orthopedic change, but also can cause significant adverse periodontal outcomes and unstable side effects. There is a clear correlation between buccal tooth movement and gingival recession and bone dehiscences. These adverse periodontal responses with RPE indicate the importance of early treatment. The beneficial periodontal effects of transverse skeletal correction have been a primary focus of our research for the past 35 to 40 years. We have emphasized the importance of correcting transverse skeletal discrepancy to: 1) prevent periodontal problems; 2) achieve greater dental and skeletal stability; 3) improve dentofacial esthetics by eliminating or improving buccal corridors; and 4) improve airway resistance. When it may be critical to save the natural dentition, we do not want to introduce adverse dental/skeletal changes for adolescent patients and/or patients with advanced periodontal disease. New advances in skeletal anchorage should permit orthopedic change without adverse dental changes by applying force directly to the maxillary bone; an innovative technique to maximize the skeletal maxillary changes in the transverse dimension is explained in this chapter. Furthermore, diagnosis of the transverse dimension—the use of cone-beam computed tomography (CBCT) for 3D evaluation of skeletal changes, the benefits of the skeletal transverse changes of the whole maxillofacial complex and its periodontal response, the changes in airway and non surgical RPE with bone-anchored appliances utilizing temporary anchorage devices (TADs)—is described and discussed.

- by Ignacio Blasi and +1
- •
- Orthodontics, Periodontics, Periodontology, Biomechanics in Orthodontics

Obesity is a widespread chronic inflammatory disorder characterized by an increased overall disease burden and significant association with periodontitis. The aim of this prospective clinical cohort study was to investigate the effect of obesity on orthodontic tooth movement. Fifty-five adolescent patients (27 males, 28 females) with a mean (SD) age of 15.1 (1.7) years and mean (SD) body mass index (BMI) of 30.2 (3.5) kg/m2 in obese and 19.4 (2.2) kg/m2 in normal-weight groups were followed from start of treatment to completion of tooth alignment with fixed orthodontic appliances. Primary outcome was time taken to complete tooth alignment, while secondary outcomes included rate of tooth movement and change in clinical parameters (plaque/gingival indices, unstimulated whole-mouth salivary flow rate, gingival crevicular fluid biomarkers). Data collection took place at baseline (start of treatment: appliance placement), 1 h and 1 wk following appliance placement, and completion of alignment. Results were analyzed by descriptive statistics followed by generalized estimating equation regression modeling. There were no significant differences between groups in time taken to achieve tooth alignment (mean [SD] 158.7 [75.3] d; P = 0.486). However, at 1 wk, initial tooth displacement was significantly increased in the obese group ( P < 0.001), and after adjusting for confounders, obese patients had a significantly higher rate of tooth movement compared with normal-weight patients (+0.017 mm/d; 95% confidence interval, 0.008-0.025; P < 0.001) over the period of alignment. Explorative analyses indicated that levels of the adipokines leptin and resistin, the inflammatory marker myeloperoxidase (MPO), and the cytokine receptor for nuclear factor kappa-B ligand (RANKL) were significantly different between obese- and normal-weight patients and associated with observed rates of tooth movement. This represents the first prospective data demonstrating a different response in obese patients compared with normal-weight patients during early orthodontic treatment. These differences in the response of periodontal tissues to orthodontic force in the presence of obesity have potential short- and long-term clinical implications.

Objective: The aim of this systematic review was to assess the occlusal outcome and duration of fixed orthodontic therapy from clinical trials in humans with the Objective Grading System (OGS) proposed by the American Board of Orthodontics. Methods: Nine databases were searched up to October 2016 for prospective/ retrospective clinical trials assessing the outcomes of orthodontic therapy with fixed appliances. After duplicate study selection, data extraction, and risk of bias assessment according to the Cochrane guidelines, random-effects meta-analyses of the mean OGS score and treatment duration were performed and 95% confidence intervals (CIs) were calculated. Results: A total of 34 relevant clinical trials including 6,207 patients (40% male, 60% female; average age, 18.4 years) were identified. The average OGS score after treatment was 27.9 points (95% CI, 25.3–30.6 points), while the average treatment duration was 24.9 months (95% CI, 24.6–25.1 months). There was no significant association between occlusal outcome and treatment duration, while considerable heterogeneity was identified. In addition, orthodontic treatment involving extraction of four premolars appeared to have an important effect on both outcomes and duration of treatment. Finally, only 10 (39%) of the identified studies matched compared groups by initial malocclusion severity, although meta-epidemiological evidence suggested that matching may have significantly influenced their results. Conclusions: The findings from this systematic review suggest that the occlusal outcomes of fixed appliance treatment vary considerably, with no significant association between treatment outcomes and duration. Prospective matched clinical studies that use the OGS tool are needed to compare the effectiveness of orthodontic appliances. [Korean J Orthod 2017;47(6):401-413]

Background: Torque of the maxillary incisors is crucial to occlusal relationship and esthetics and can be influenced by many factors. The aim of this study was to assess the relative influence of the material of the orthodontic appliance (adhesive, bracket, ligature, and wire) on tooth displacements and developed stresses/strains after torque application. Methods: A three-dimensional upper right central incisor with its periodontal ligament (PDL) and alveolus was modeled. A 0.018-in. slot discovery® (Dentaurum, Ispringen, Germany) bracket with a rectangular 0.018 x 0.025-in. wire was generated. The orthodontic appliance varied in the material of its components: adhesive (composite resin or resin-modified glass ionomer cement), bracket (titanium, steel, or ceramic), wire (beta-titanium or steel), and ligature (elastomeric or steel). A total of 24 models were generated, and a palatal root torque of 5° was applied. Afterwards, crown and apex displacement, strains in the PDL, and stresses in the bracket were calculated and analyzed.

This article describes the orthodontic treatment of an adolescent patient
presenting a class II skeletal, convex profile, mesofacial biotype, upper dental
midline deviated 1 mm to the left, Class I bilateral molar, canine distoclusion of
½ right unit and left canine relationship non-determinable because piece 23 is in
ectopic position, proinclination and inferior protrusion. The treatment plan was to
distalize the maxillary molars and create enough space to incorporate pieces 13,
23 in the dental arch, a pendulum appliance supported with two orthodontic mini
implants were used. The active treatment lasted 18 months and at the end of it, all
the objectives were fulfilled, resulting in facial balance. The pendulum appliance
is a good alternative for a Class II dental correction, it produces distalization of the
maxillary molars in an optimal treatment time

- by Manuel E Bravo and +2
- •
- Orthodontics, Biomechanics in Orthodontics, Orthodontic Research, Dentistry and Orthodontics

- by Fariborz Amini
- •
- Microbiology, Dentistry, Orthodontics, Biotechnology

Background: The aim of this study was to compare the torque efficacy of square and rectangular wires in
0.018- and 0.022-in. conventionally ligated brackets.
Methods: Brackets of the same prescription were evaluated in both slot dimensions. Identical acrylic resin
models of the maxilla were bonded with the brackets and mounted on the Orthodontic Measurement and
Simulation System. Ten 0.018 × 0.018 in., 0.018 × 0.022 in., and 0.018 × 0.025 in. stainless steel wires were
evaluated in the 0.018-in. brackets and ten 0.019 × 0.019 in., 0.019 × 0.025 in., and 0.019 × 0.026 in. stainless
steel wires were evaluated in the 0.022-in. brackets. A 15° buccal root torque was gradually applied to the
right central incisor bracket, and the moments were recorded at this position. One-way ANOVA was applied
for both bracket slot sizes along with post hoc analysis for the various archwire sizes.
Results: The mean measured moments varied between 10.78 and 30.60 Nmm among the assessed wire-and-bracket
combinations. Both square and rectangular archwires in the 0.018-in. bracket system exerted statistically significantly
higher moments in comparison with their counterparts in the 0.022-in. bracket system. Rectangular archwires exerted
statistically significantly higher moments than square archwires, both for the 0.018- and the 0.022-in. bracket system.
Conclusions: Rectangular archwires seem to be more efficient in torque exertion, especially in 0.018-in. brackets.

Objectives: To compare the failure pattern of four different bracket types and to assess its effect on treatment duration. Materials and Methods: A total of 78 white patients (28 male, 50 female) with a mean age of 12.6 years were included in this retrospective cohort study and treated for a mean period of 30.6 months. The patients were treated in a private practice with stainless steel conventionally ligated brackets, ceramic conventionally ligated brackets, stainless steel self-ligating brackets, or nickel-free self-ligating brackets. The loss of at least one bracket during the course of treatment was analyzed with Cox proportional hazards survival analyses and generalized linear regression. Results: The overall bracket failure rate at the tooth level was 14.1% (217 brackets), with significant differences according to tooth type (between 8.0%–23.4%) and bracket type (between 11.2%–20.0%). After taking confounders into account, patients treated with ceramic brackets lost more brackets (hazard ratio ¼ 1.62; 95% confidence interval ¼ 1.14–2.29; P ¼ .007) than patients with stainless steel brackets. On average, treatment time increased by 0.6 months (95% confidence interval ¼ 0.21–1.05; P ¼ .004) for each additional failed bracket. Conclusions: Bracket failure was more often observed with ceramic brackets and was associated with increased treatment duration. (Angle Orthod. 0000;00:000–000.)

Extraction of premolar teeth to manage class I malocclusion is conventionally the management approach of choices. However class I malocclusion with tooth tissue discrepancy could be manage with the extraction of a lower incisor tooth with a more acceptable aesthetic outcome. This article describe a cases of class I malocclusion mange with extracting a mandibular lower incisor tooth. DOI: http://dx.doi.org/10.3329/updcj.v3i1.17987 Update Dent. Coll. j: 2013; 3 (1): 54-57

- by Nazmul Hasan
- •
- Dentistry, Orthodontics, Biomechanics in Orthodontics, Orthodontic Research

A priori registration of randomized clinical trials is crucial to the transparency and credibility of their findings. Aim of this study was to assess the frequency with which registered and completed randomized trials in orthodontics are published. We searched ClinicalTrials.gov and ISRCTN for registered randomized clinical trials in orthodontics that had been completed up to January 2017 and judged the publication status and date of registered trials using a systematic protocol. Statistical analysis included descriptive statistics, chi-square or Fisher exact tests, and Kaplan-Meier survival estimates. From the 266 orthodontic trials registered up to January 2017, 80 trials had been completed and included in the present study. Among these 80 included trials, the majority (76%) were registered retrospectively, while only 33 (41%) were published at the time. The median time from completion to publication was 20.1 months (interquartile range: 9.1 to 31.6 months), while survival analysis indicated that less than 10% of the trials were published after 5 years from their completion. Finally, 22 (28%) of completed trials remain unpublished even after 5 years from their completion. Publication rates of registered randomized trials in orthodontics remained low, even 5 years after their completion date.

- by Spyridon Papageorgiou
- •
- Orthodontics, Evidence Based Medicine, Randomization, Randomized Evaluation

The aim of this study was to investigate through the review of literature particularities of the self ligating brackets. Looking for cientific support for questions like: lower friccion, improving mainly sliding mechanics, lower biological cost, lower apical root resorption risk, less pain, faster treatments, less chairtime, fewer appoitments, lower bacterial number because off the ligature elimination. Such questions will be just an enthusiasm for a new product? Or, self ligating appliances really improves the efficiency of the orthodontic treatment?
Key words: self ligating appliances, lower friccion, orthodontic mechanic

Dental transposition is a form of ectopic eruption with change in position of normal adjacent teeth. Its prevalence is very low in general population and could be frequently missed on oral examination. We present a rare case of dental... more

- by Abu Naim
- •
- Dentistry, Orthodontics, Biomechanics in Orthodontics, Dentistry and Orthodontics

Patients of Dr. Hutta were generally impressed and gave good reviews for the “honest, skilled” dentist, the “no hidden or extra costs with services”, and the “friendly, helpful” front desk staff and assistants. Other patients gave praise for “how they’re always on time”, the “professional, always happy and helpful” staff and assistants, and the convenient office hours and location.

Introduction: Biomechanical analysis of orthodontic tooth movement is complex, as many different
tissues and appliance components are involved. The aim of this finite element study was to assess
the relative effect of material alteration of the various components of the orthodontic appliance on
the biomechanical behaviour of tooth movement.
Methods: A three-dimensional finite element solid model was constructed. The model consisted
of a canine, a first, and a second premolar, including the surrounding tooth-supporting structures
and fixed appliances. The materials of the orthodontic appliances were alternated between: (1)
composite resin or resin-modified glass ionomer cement for the adhesive, (2) steel, titanium,
ceramic, or plastic for the bracket, and (3) β-titanium or steel for the wire. After vertical activation
of the first premolar by 0.5 mm in occlusal direction, stress and strain calculations were performed
at the periodontal ligament and the orthodontic appliance.
Results: The finite element analysis indicated that strains developed at the periodontal ligament
were mainly influenced by the orthodontic wire (up to +63 per cent), followed by the bracket (up to
+44 per cent) and the adhesive (up to +4 per cent). As far as developed stresses at the orthodontic
appliance are concerned, wire material had the greatest influence (up to +155 per cent), followed
by bracket material (up to +148 per cent) and adhesive material (up to +8 per cent).
Limitations: The results of this in silicostudy need to be validated by in vivostudies before they
can be extrapolated to clinical practice.
Conclusion: According to the results of this finite element study, all components of the orthodontic
fixed appliance, including wire, bracket, and adhesive, seem to influence, to some extent, the
biomechanics of tooth movement.

- by Spyridon Papageorgiou
- •
- Orthodontics, Clinical Trials, Clinical Trial, Clinical Epidemiology

Introduction: Torque of the maxillary incisors is essential in esthetics and proper occlusion, while torque expression is influenced by many factors. The aim of this finite element study was to assess the relative effect of tooth morphology, bracket prescription, and bracket positioning on tooth displacement and developed stresses/strains after torque application. Methods: A three-dimensional upper right central incisor with its periodontal ligament (PDL) and alveolus was modelled. The tooth varied in the crown–root angle (CRA) between 156°, 170°, and 184°. An 0.018-inch slot discovery® (Dentaurum, Ispringen, Germany) bracket with a rectangular 0.018 × 0.025-inch β-titanium wire was modelled. Bracket torque prescription varied between 0°, 12°, and 22°, with bracket placement at the centre of the middle, gingival or incisal third of the crown. A total of 27 models were generated and a buccal root torque of 30° was applied. Afterwards, crown and apex displacement, strains in the PDL, and stresses in the bracket were calculated and analysed statistically. Results: The palatal crown displacement was significantly affected by bracket positioning (up to 94 per cent), while the buccal apex displacement was significantly affected by bracket prescription (up to 42 per cent) and bracket positioning (up to 23 per cent). Strains in the PDL were affected mainly by CRA (up to 54 per cent), followed by bracket positioning (up to 45 per cent). Finally, bracket prescription considerably affected the stresses in the bracket (up to 144 per cent). Limitations: These in silico results need to be validated in vivo before they can be clinically extrapolated. Conclusion: Tooth anatomy and the characteristics of the orthodontic appliance should be considered during torque application.

Jim Hutta Westerville OH, James T. Hutta is a native of Columbus and a graduate of Ohio State College of Biological Sciences with his undergraduate degree and Ohio State College of Dentistry where he received his dental degree. After graduation from dental school, Dr. Hutta completed a three-year residency in Orthodontics at the Eastman Dental Center, University of Rochester School of Medicine. He is also a current member of the American Association of Orthodontists, American Dental Association, Ohio Dental Association, International College of Dentists, and also serves on the Board of Directors on the Columbus Dental Society. He has many awards, including the 2010 Greater Columbus Readers Choice Award and was voted as one of the top Orthodontists in Columbus by his peers in 2011.

- by Jim Hutta
- •
- Orthodontics, Biomechanics in Orthodontics
- by Spyridon Papageorgiou
- •
- Orthodontics, Open Access, Health And Clinical Research, Open Data

Sleeping sideways or on your stomach can unbalance the jaw, creating problems in the teeth and stomatognathic system, posture, and joints. Sleeping lying in the stomach up position, on the contrary, can prevent the appearance of more or less serious disorders such as halitosis, periodontitis, pyorrhea, resulting in tooth loss, and even serious changes in the temporomandibular joint, posture and the whole psychophysical balance.

- by Gino Salvatore Galiffa
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- Orthodontics, Otolaryngology, Biomechanics in Orthodontics, Odontology

is is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is... more