The Angle Orthodontist (ANGLE ORTHOD)

Publications in this journal

• Article: Influence of low-level laser on bone remodeling during induced tooth movement in rats.

  Eliziane Cossetin, Guilherme Janson, Maria Goretti F de Carvalho, Rejane A de Carvalho, José Fernando Castanha Henriques, Daniela Garib
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  ABSTRACT: Abstract Objective: To analyze the effect of low-level laser on bone remodeling during induced tooth movement in rats. Materials and Methods: A diode laser (808 nm, 100 mW, 54 J on an area of 0.0028 cm(2)) was used. The application was continuous, punctual, and with contact. Forty-two 70-day-old Wistar rats had the maxillary left first molar moved using a force level of 25 g. In two experimental subgroups the movement was performed over 7 days and in three subgroups the movement occurred over 14 days. In the 7-day movement subgroups, one subgroup received laser irradiation on day 1 only; the other subgroup received laser irradiation on days 1, 3, and 5. In the 14-day movement subgroups, one subgroup received laser irradiation on day 1 only; the second on days 1, 3, and 5; and the third on days 1, 3, 5, 7, 9, 11, and 13. The control group was also divided into two subgroups, and movement occurred over two different periods of treatment (7 days and 14 days) without laser application; these were used as controls for the respective experimental subgroups. Inter-subgroup comparison was performed with Kruskal-Wallis, followed by Mann-Whitney and analysis of variance, followed by Tukey tests within the 7- and 14-day subgroups. Results: The subgroup with three laser applications showed significantly greater osteoclastic activity and bone resorption than the other subgroups in the 7-day movement subgroups. Conclusions: Low-level laser application significantly increased the osteoclastic but not the osteoblastic activity during the initial phases of tooth movement. In addition, the osteoclastic activity was dose-dependent.
  The Angle Orthodontist 05/2013;
• Article: Effects of wobbling angle on the stability measures of orthodontic mini-implants during insertion and removal procedures.

  Il-Sik Cho, Sang-Ho Baek, Young Ho Kim
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  ABSTRACT: Abstract Objective: To investigate the effects of wobbling angle on the stability measures of orthodontic mini-implants (OMIs) during insertion and removal procedures in artificial bone blocks. Materials and Methods: A total of 36 OMIs (self-drilling type, cylindrical shape, 7 mm in length, 1.45 mm in diameter) were allocated into three groups according to the amount of wobbling angle (W-0°, W-2°, and W-4° groups; N = 12 per group). The OMIs were installed and subsequently removed from artificial bone blocks (Sawbone) using a driving torque tester with a uniform speed of 28 rpm. Insertion peak time (IPT), maximum insertion torque (MIT), total insertion energy (TIE), near-peak insertion energy (NPIE), maximum removal torque (MRT), and near-peak removal energy (NPRE) were measured. Results: The W-4° group showed the longest IPT and highest TIE and NPIE, followed by the W-2° and W-0° groups (W-0° < W-2° < W-4°, all P < .001). The W-2° and W-4° groups showed significant increase in MIT compared with the W-0° group (W-0° < [W-4°,W-2°]; P < .001). Although there was no significant difference in NPRE among the three groups, the W-4° group showed a decrease in MRT compared with the W-0° and W-2° groups (W-4° < {W-2°,W-0°]; P < .05). Although the W-4° group showed a 14.5% (2.9 Ncm) increase in MIT compared with the W-0° group, there was only a 6% (1.3 Ncm) decrease in MRT from the W-0° group to the W-4° group. Conclusion: Slight wobbling during the OMI insertion procedure may be acceptable in terms of the stability measures of OMIs during insertion and removal procedures.
  The Angle Orthodontist 05/2013;
• Article: Segregation analysis of mandibular prognathism in Korean orthognathic surgery patients and their families.

  Jeong-Min Ko, Young Ju Suh, Jongrak Hong, Jun-Young Paeng, Seung-Hak Baek, Young Ho Kim
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  ABSTRACT: Abstract Objective: To investigate the existence of genetic influences on the incidence of mandibular prognathism (MP) in Korean Class III patients. Materials and Methods: The probands consisted of 100 Class III patients with MP (51 men and 49 women; mean age, 22.1 ± 5.2 years; SNA, 81.2° ± 3.2°; SNB, 84.1° ± 3.9°) who underwent orthognathic surgery. Using three-generation pedigree charts, questionnaires, and clinical examinations, general information and information regarding MP for a total of 3777 relatives of the probands (1911 men and 1866 women) was ascertained. Familial correlations of MP between possible pairs in the pedigree were estimated. Heritability (h(2)) of MP under various models was estimated. Segregation analysis was conducted under the assumption of the nonpolygenic multivariate logistic model and finite polygenic mixed model. One-, two-, and three-susceptibility-type models were evaluated. Results: Among 3777 relatives, 199 (97 men and 102 women) were affected with MP (5.3%). Correlation coefficients of MP incidence in full siblings and in parent-offspring were .2003 and .2036, respectively (all P < .001). The h(2) of MP was estimated as 21.5% after adjusting for sex and founder effects. Two- and three-susceptibility-type models showed that the general model fit better than the other models. MP incidence did not have a major gene transmission model and was influenced by numerous minor effect genes and their additive effects. Conclusion: These results suggest that the inherited susceptibility to MP in Korean Class III patients might be due to the summation of minor effects from a variety of different genes and/or influence of environmental factors, rather than Mendelian transmission of major genes.
  The Angle Orthodontist 05/2013;
• Article: Expression patterns of nociceptin in rats following experimental tooth movement.

  Lina Liao, Xiaochuan Hua, Hu Long, Niansong Ye, Yang Zhou, Sheng Wang, Wenli Lai
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  ABSTRACT: Abstract Objectives: To determine the expression levels of nociceptin following experimental tooth movement. Materials and Methods: A total of 72 male Sprague-Dawley rats were divided into two groups: sham and experimental groups. For the experimental group, closed coil springs were used to mimic orthodontic force (80 g) between upper incisors and first molars, and the rats were killed at 0 hours, 4 hours, 12 hours, 1 day, 2 days, 5 days, 7 days, 10 days, and 14 days. All of these procedures were similar for the sham group, except for that no force was applied. The four rats killed at 0 hours without any intervention were used as the baseline control in each group. Trigeminal nucleus caudalis from both the ipsilateral and contralateral sides of force applications were obtained for immunostaining. Results: Nociceptin was expressed in both the ipsilateral and contralateral sides of each group. Its expression levels started to increase on day 2, peaked on day 7, and returned to baseline on day 10 in the experimental group, while expression levels started to decrease on day 1 and returned to baseline on day 10 in the sham group. Moreover, the expression levels were similar between the ipsilateral and contralateral sides in each group. Conclusion: The expression levels of nociceptin were elevated following experimental tooth movement. The anesthetic agent used in this study (chloral hydrate) may have an antagonism with nociceptin. Due to bilateral innervation of anterior teeth and bilateral projection of nerve fibers, the expression levels of nociceptin were similar between ipsilateral and contralateral sides.
  The Angle Orthodontist 05/2013;
• Article: Coating stability and surface characteristics of esthetic orthodontic coated archwires.

  Dayanne Lopes da Silva, Claudia Trindade Mattos, Renata Autoun Simão, Antônio Carlos de Oliveira Ruellas
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  ABSTRACT: Abstract Objective: To evaluate the coating thickness of four brands of as-received esthetic coated rectangular archwires and their surface characteristics and coating stability after 21 days of oral exposure compared to those of conventional stainless steel (SS) and nickel titanium (NiTi) ones. Materials and Methods: The labial surface of the selected archwires was observed with a stereoscope and in a scanning electron microscope, and surface roughness was assessed with an atomic force microscope. The coating thickness of as-received wires and the percentage of coating lost on the labial surface of retrieved wires were measured using Image Pro Plus 4.5 software. Results: All groups showed an average coating thickness of less than 0.002 inches. After oral exposure, archwires from two groups lost all coating on the labial surface. On average, 28.71% and 72.90% of the coating was lost in each of the other two groups, and the surface roughness of the remaining coating was higher than postclinical control wires. Conclusion: Coated archwires had a low esthetic value as they presented a nondurable coating. The remaining coating showed a severe deterioration and a greater surface roughness than postclinical control counterparts (conventional SS and NiTi wires).
  The Angle Orthodontist 05/2013;
• Article: Bone- and dentoalveolar-anchored dentofacial orthopedics for Class III malocclusion: New approaches, similar objectives?

  Marta Morales-Fernández, Alejandro Iglesias-Linares, Rosa Maria Yañez-Vico, Asuncion Mendoza-Mendoza, Enrique Solano-Reina
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  ABSTRACT: ABSTRACT Objectives: To analyze the scientific literature and compare in the results of conventional orthopedic appliances with those obtained from recent bone-anchored orthopedics for Class III malocclusion. Materials and Methods: The literature was systematically reviewed using PubMed/Medline, Scopus, and Scirus databases up to January 2012. Articles were selected by two different researchers (kappa index = 0.83), based on established inclusion/exclusion criteria. Methodologic quality was classified as high, medium, or low quality. Results: The search strategy identified 1020 titles. Thirty studies were selected after applying the criteria (high quality = 9, medium quality = 21). Protraction rates differed within a range of one- to twofold between bone-anchored and dentoalveolar therapies (P < .001). All studies noted the effect of clockwise rotation on the mandible and an increase in inferior-anterior and total facial height; this was more obvious in dentoalveolar therapy than in bone-anchored orthopedics (P < .001). Conclusions: Dental parameters like overjet increased significantly with both sets of groups, ranging from 1.7 to 7.9 mm with dentoalveolar therapy and from 2.7 to 7.6 mm with bone-anchored orthopedics.
  The Angle Orthodontist 05/2013; 83(3):540-52.
• Article: Supporting Open Access and the AAOF.

  Steven J Lindauer
  The Angle Orthodontist 05/2013; 83(3):553.
• Article: Mechanical stability and clinical applicability assessment of novel orthodontic mini-implant design.

  Ha Na Song, Christine Hong, Robert Banh, Tania Ohebsion, Greg Asatrian, Ho-Yin Leung, Benjamin M Wu, Won Moon
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  ABSTRACT: Abstract Objective: To compare the stability and clinical applicability of a novel orthodontic mini-implant design (N2) with the most widely used commercially available (CA) design. Materials and Methods: Two groups of mini-implants were tested: a CA design (1.5-mm diameter, 6-mm length) and N2 (3-mm diameter, 2-mm length, tapered shape). Implants were inserted in bone blocks of cortical bone simulation with varying densities (20 pounds per cubic foot [pcf], 30 pcf, and 40 pcf). A torque test was used to measure maximum insertion torque (MIT) and maximum removal torque (MRT). Compression and tension force vectors were applied at angles of 10°, 20°, 30°, and 40° using customized load pins to determine primary stability. Results: Mean MIT and MRT were higher in the N2 than the CA design at all three cortical bone densities except MRT in 20 pcf bone (not statistically significant). The mean compression force required to displace the N2 at all distances and angulations was greater for the N2 than the CA design. At all displacement distances, the highest mean tension force required for N2 displacement was at 10° angulation, whereas at 30° and 40°, the mean tension force required to displace the CA design was greater. Conclusions: The primary stability of the N2 is superior to that of the CA design and is promising for both orthodontic and orthopedic clinical applicability, especially under compression force. The short length of the N2 reduces risk of damage to anatomic structures and root proximity during placement and orthodontic treatment. The stability of the N2 may be compromised in areas of high bone density and highly angulated tension force.
  The Angle Orthodontist 04/2013;
• Article: Effect of bracket bevel design and oral environmental factors on frictional resistance.

  Chen-Jung Chang, Tzer-Min Lee, Jia-Kuang Liu
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  ABSTRACT: Abstract Objective: To investigate the effects of bracket bevel design and oral environmental factors (saliva, temperature) on frictional resistance. Materials and Methods: Five types of brackets, namely a conventional bracket (Omni-arch), an active self-ligating bracket (Clippy), and three passive self-ligating brackets (Carriere, Damon, and Tenbrook T1) coupled with a 0.014-inch austenitic nickel-titanium archwire were tested. In the experimental model, which used a group of five identical brackets, the center bracket was displaced 3 mm to mimic the binding effects. The friction experiments were performed at three temperatures (20°C, 37°C, 55°C) in a dry or a wet (artificial saliva) state. Finally, the surfaces of the bracket slots were observed using scanning electron microscopy (SEM) before and after the friction tests. Results: The sliding frictional force was significantly influenced by the bracket slot bevel and saliva whether in the active or passive configuration (P < .05). The frictional force significantly increased as the temperature increased in the active configuration (P < .01). Based on the SEM observations, a correlation was found among the level of frictional force, the bevel angle, and the depth of scratches on bracket bevels. Conclusion: Frictional force can be reduced by increasing the bevel angle and by lowering the oral temperature, whereas the presence of saliva increases frictional resistance.
  The Angle Orthodontist 04/2013;
• Article: Effects of wear time recording on the patient's compliance.

  Alexander Pauls, Manuel Nienkemper, Agamemnon Panayotidis, Benedict Wilmes, Dieter Drescher
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  ABSTRACT: Objective: To assess the effect of wear-time recording on subjective and objective wear time. Materials and Methods: This study retrospectively examined a group of 18 patients and a control group of 14 patients at four appointments over 168 days. The patients were treated with removable appliances with embedded TheraMon-microsensors to be worn for 15 hours per day. The study group was not told about the microsensor until the first appointment after fitting of the appliance. At each appointment patients were asked about their subjective wear time and afterward were told about the objective wear time. The existence of the microsensor was revealed to the control group when the appliance was fitted. Objective wear time was also announced at every appointment. Results: Mean wear times did not significantly differ between groups at any appointment or regarding overall wear time. Highly significant differences between subjective and objective wear time were found when patients did not know that their wear time had been monitored. Conclusion: Mean wear times assessed in this study concur with data of previous studies. Patients tend to overestimate their wear times but become more realistic once they know wear time is being monitored. Objective measurement of wear time allows a more realistic view of compliance by patient and orthodontist. Knowing that wear time is recorded does not necessarily increase the amount of time removable appliances are worn by the patient.
  The Angle Orthodontist 04/2013;
• Article: Impact of malocclusion on the quality of life of Saudi children.

  Irfan Dawoodbhoy, Elsa K Delgado-Angulo, Eduardo Bernabé
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  ABSTRACT: Objective: To assess the relationship between malocclusion severity and quality of life in children. Materials and Method: Two hundred and seventy-eight children aged 11 to 14 years were recruited voluntarily from the Dental and Maxillofacial Centre of the Almana General Hospital in Alkhobar, Saudi Arabia. The children were asked to fill out the Arabic version of the Child Perception Questionnaire for 11- to 14-year-old children (CPQ11-14) and were then clinically examined to determine the severity of their malocclusion using the Dental Aesthetic Index (DAI). Multivariate analysis of variance was used to compare the four domains and the total CPQ11-14 scores between the four DAI severity groups. Results: Significant differences were found between DAI severity groups for the four domains and the total CPQ11-14 scores. Although children with very severe (handicapping) malocclusion had significantly higher domain and total CPQ11-14 scores than all the other groups (differences of up to 6 and 22 units, respectively, compared to children with no/minor malocclusion), there were no differences between those with no/minor, definite, and severe malocclusion. Conclusion: These findings suggest that only very severe malocclusion had an impact on the quality of life of the participants. Orthodontists should focus not only on clinical measures of malocclusion but should also consider the impact of severe malocclusion on patients' quality of life.
  The Angle Orthodontist 04/2013;
• Article: Photographic assessment of cephalometric measurements.

  Liliane de Carvalho Rosas Gomes, Karla Orfelina Carpio Horta, Luiz Gonzaga Gandini, Marcelo Gonçalves, João Roberto Gonçalves
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  ABSTRACT: Objective: To investigate the relationship between craniofacial measurements obtained from cephalometric radiographs and analogous measurements from profile photographs. Materials and Methods: Lateral cephalograms and standardized facial profile photographs were obtained from a sample of 123 subjects (65 girls, 58 boys; age 7-12 years). Intraclass correlation coefficients (ICCs) were calculated from repeated photographic measurements to evaluate method reliability. Analogous cephalometric and photographic measurements were compared to assess Pearson correlation coefficients. Linear regression analyses were conducted between the measurements that achieved correlation coefficients greater than r = 0.7. Results: The reliability of the photographic technique was satisfactory. Most measurements showed ICCs above 0.80 and highly significant correlations (P ≤ .001) with cephalometric variables. Among all measurements used, the A'N'B' angle was the most effective in explaining the variability of its analogous cephalometric, mainly for female subjects (r(2) = 0.80). The FMA' angle showed the best results for vertical assessment (r(2) = 0.65). Conclusions: The photographic method has proven to be a repeatable and reproducible tool provided that a standardized protocol is followed. Therefore, it may be considered a feasible and practical diagnostic alternative, particularly if there is a need for a low-cost and noninvasive method.
  The Angle Orthodontist 04/2013;
• Article: Virulence modulation of Streptococcus mutans biofilms by metal ions released from orthodontic appliances.

  Alinne Ulbrich Mores Rymovicz, Maiara Medeiros Ronsani, Ana Maria Trindade Grégio, Odilon Guariza Guariza-Filho, Orlando Tanaka, Edvaldo Antonio Ribeiro Rosa
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  ABSTRACT: Abstract Objectives: To evaluate the impact of metal ions commonly shed from orthodontic appliances on the virulence of Streptococcus mutans ATCC®25175™ biofilms. Materials and Methods: Biofilms were grown in the presence of Ni(2+), Fe(3+), Cr(3+), Co(2+), and a metal ion pool at concentrations similar to those released in saliva of orthodontic patients for 72 hours. Once mature, biofilms were treated for up to 12 hours with 5% glucose. Results: Ions interfered with the growth of S mutans by reducing its biomass (Ni(2+), Fe(3+), Cr(3+)), raising its rates of sugar metabolism (Ni(2+), Fe(3+), Cr(3+)), and raising its secretion of lactate (Ni(2+), Fe(3+), Cr(3+), pool). Conclusion: The laboratory data presented here point to the possibility of virulence increase of S mutans by metal ions commonly released during orthodontic therapy.
  The Angle Orthodontist 04/2013;
• Article: Comparison of adverse effects between lingual and labial orthodontic treatment.

  Hu Long, Yang Zhou, Ujjwal Pyakurel, Lina Liao, Fan Jian, Junjie Xue, Niansong Ye, Xin Yang, Yan Wang, Wenli Lai
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  ABSTRACT: Abstract Objective: To compare adverse effects between labial and lingual orthodontic treatments through a systematic review of the literature. Materials and Methods: The protocol of this systematic review (CRD42012002455) was registered in the International Prospective Register of Systematic Reviews (PROSPERO). An electronic search was conducted in PubMed, Embase, Web of Science, CENTRAL, SIGLE, ProQuest Dissertations & Theses, and ClinicalTrial.gov for articles published between January 1980 and December 2012. Primary outcomes included pain and caries; secondary outcomes were eating difficulty, speech difficulty, oral hygiene, and treatment duration. Meta-analyses were conducted in Comprehensive Meta-Analysis version 2.2.064. Results: Six studies were included, two randomized controlled trials and four clinical controlled trials; of these, four were medium quality and two were low quality in terms of the risk of bias. Five of the six outcomes were evaluated in the included studies, and treatment duration was not; pain, eating difficulty, speech difficulty were statistically pooled. Meta-analysis revealed that the pooled odds ratios were 1.20 (95% confidence interval [CI] = 0.30-4.87) for overall pain, 32.24 (95% CI = 14.13-73.55) for pain in tongue, 0.08 (95% CI = 0.04-0.18) for pain in cheek, 0.11 (95% CI = 0.03-0.42) for pain in lip, 3.59 (95% CI = 1.85-6.99) for eating difficulty, and 8.61 (95% CI = 3.55-20.89) for speech difficulty. Sensitivity analysis showed consistent results except for eating difficulty. No publication bias was detected. Conclusions: The likelihood of overall pain was similar between the two modalities. Patients who underwent lingual orthodontic treatment were more likely to suffer from pain in the tongue and less likely to suffer from pain in the cheek and lip. Lingual orthodontic treatment increased the likelihood of speech difficulty. Eating difficulty, oral hygiene, caries, and treatment duration could not be compared in this systematic review.
  The Angle Orthodontist 04/2013;
• Article: Effects of bracket design on critical contact angle.

  Xiaomo Liu, Peng Ding, Jiuxiang Lin
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  ABSTRACT: Abstract Objective: To explore how the position of the bracket slots relative to the archwire influences the friction between them, and how bracket design affects the critical contact angle (θc). Materials and Methods: Two kinds of stainless steel archwires (0.016 and 0.019 × 0.025-inch) were tested against four kinds of brackets (Transmission Straight Archwire bracket, Domestic MBT bracket, Tip-Edge Plus bracket, and BioQuick self-ligation bracket) in the dry state. Resistance to sliding (RS) was measured as an increase in contact angle (θ). The value of θc was calculated by two linear regression lines. Results: Friction remained stable when θ < θc, then increased linearly when θ > θc. The θc values of the Tip-Edge Plus bracket and Transmission Straight Archwire bracket were significantly larger than those for the Domestic MBT bracket and BioQuick self-ligation bracket. Conclusions: The relationship between the archwire and bracket slot significantly affects the resistance to sliding. The "edge-off" structure of the Tip-Edge Plus bracket and Transmission Straight Archwire bracket could help to increase the θc value, and to expand the passive configuration range.
  The Angle Orthodontist 04/2013;
• Article: Unilaterally impacted maxillary central incisor and canine with ipsilateral transposed canine-lateral incisor.

  Po-Sung Fu, Jen-Chyan Wang, Yi-Min Wu, Ta-Ko Huang, Wen-Cheng Chen, Yu-Chuan Tseng, Chin-Huang Tseng, Chun-Cheng Hung
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  ABSTRACT: Abstract Concurrent impaction and transposition of maxillary anterior teeth is uncommon and poses a challenge for dentists. Early diagnosis and management of eruption disturbances benefits esthetic and functional outcomes. This article describes the treatment of a teenager who had impactions of the left maxillary central incisor and canine as well as ipsilateral canine-lateral incisor transposition. Treatment alternatives and effective orthodontic techniques are delineated. To optimize the treatment results, the impacted maxillary canine was surgically exposed and orthodontically distalized with an innovative cantilever. Subsequently, the deeply impacted maxillary central incisor was uncovered and orthodontically mesialized into the arch. Finally, the displaced maxillary lateral incisor was brought into its normal position. The combined surgical-orthodontic approach resolved a difficult clinical issue and avoided additional restorations. An esthetic, functional outcome was achieved and satisfied the patient.
  The Angle Orthodontist 04/2013;
• Article: A novel experimental model for studying transverse orthodontic tooth movement in the rat mandible.

  Ayad Alsagheer, Loren W Kline, Michael R Doschak, Paul W Major
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  ABSTRACT: Abstract Objectives: To establish a rat model of a one-piece mandible using the principles of gingivoperiosteoplasty and guided bone regeneration to fuse the midline symphyseal area. Material and Methods: Twenty-four Sprague-Dawley female rats were divided into two groups: 12 experimental and 12 control. Both groups were imaged using in vivo micro-computed tomography at baseline and at end point (5 months). The experimental group received regenerative surgery at the symphysis area; the control group received no treatment. Outcomes were evaluated by radiographic examination of gross and volumetric bony changes in the symphyseal region of interest marked between the mental foramina bilaterally and the two central incisors near the most coronal margin of the alveolar crests. These landmarks were chosen as they can be reproduced on the computed tomography images at baseline and end point. Histologic examination was performed on all samples at a level 5 mm apical to the alveolar bone crest. Results: Radiologic and histologic examinations of the experimental group revealed complete bony fusion of the symphyseal area in three subjects, partial fusion in five subjects, and thickening of the alveolar bony socket in three subjects; one rat died of anesthesia-related complications. No evidence of fusion or alveolar bone thickening was found in any of the controls. Conclusions: This surgical animal model demonstrates that a rat mandible can be surgically manipulated to mimic the one-piece human mandible. This novel model may prove useful in studying mandibular bone remodeling and orthodontic mandibular tooth movement.
  The Angle Orthodontist 03/2013;
• Article: The influence of lower lip position on the perceived attractiveness of chin prominence.

  Faranak Modarai, Jane Catalina Donaldson, Farhad B Naini
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  ABSTRACT: Abstract Objectives: To evaluate the influence of the lower lip prominence for varying degrees of chin prominence in the sagittal plane and to establish whether lower lip prominence affects the perceived desire for surgery. To assess differences in preference between orthodontists and laypeople as well as the effect of age, gender, and ethnicity of observers on perceptions of attractiveness and desire for surgery. Materials and Methods: A silhouette of an idealized profile image was created. The image was manipulated to create six images demonstrating different degrees of retrogenia and progenia altered in 4-mm increments from -12 mm to +12 mm and six images demonstrating chin and lower lip prominence in 4-mm increments from -12 mm to +12 mm. One hundred laypeople and 30 orthodontists ranked the images from the most to the least attractive. A duplicate of one of the images was used in order to assess intraexaminer reliability. Results: The amount and direction of sagittal chin position and the prominence of the lower lip were found to have a significant effect on image rank. Chin protrusion was less attractive than retrusion and surgery was desired more often for these images. The overall direction of opinion was the same for laypeople and orthodontists. Conclusions: The chin prominence observed in a progenic patient is deemed less attractive than the combined chin and lower lip prominence observed in a patient with mandibular prognathism. In profiles with a more prominent chin a more protrusive lower lip position was preferred. When the chin was retrusive, a normal lower lip position was preferred to a retrusive lip.
  The Angle Orthodontist 03/2013;
• Article: Bracket base remnants after orthodontic debonding.

  Matteo Zanarini, Antonio Gracco, Monica Lattuca, Silvia Marchionni, Maria Rosaria Gatto, Giulio Alessandri Bonetti
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  ABSTRACT: Abstract Objective: To evaluate whether the debonding procedure leads to restitutio ad integrum of the enamel surface by investigating the presence of enamel within the bracket base remnants after debonding. Materials and Methods: Sixty patients who completed orthodontic treatment with fixed appliances were included. A total of 1068 brackets were microphotographed; the brackets presenting some remnants on the base (n = 818) were selected and analyzed with ImageJ software to measure the remnant area. From this population a statistically significant sample (n = 100) was observed under a scanning electron microscope to check for the presence of enamel within the remnants. Energy dispersive x-ray spectrometry was also performed to obtain quantitative data. Results: Statistically significant differences in the remnant percentage between arches were observed for incisor and canine brackets (P < .0001 and P = .022, respectively). From a morphologic analysis of the scanning electron micrographs the bracket bases were categorized in 3 groups: group A, bases presenting a thin enamel coat (83%); group B, bases showing sizable enamel fragments (7%); group C, bases with no morphologic evidence of enamel presence (10%). Calcium presence was noted on all evaluated brackets under energy dispersive x-ray spectrometry. No significant difference was observed in the Ca/Si ratio between group A (16.21%) and group B (18.77%), whereas the Ca/Si ratio in group C (5.40%) was significantly lower than that of the other groups (P < .323 and P = .0001, respectively). Conclusion: The objective of an atraumatic debonding is not achieved yet; in some cases the damage could be clinically relevant.
  The Angle Orthodontist 03/2013;