no abstract available
Aim: To evaluate and compare the anteroposterior relationship of the maxillary central incisors to the forehead in white male adults with harmonious profiles and white male adult orthodontic patients.
Methods: Photographs of 101
white male adults with good facial harmony (control sample) were compared with photographs of 97 white male adults seeking orthodontic treatment
(study sample). All were profile images with the maxillary central incisors and foreheads in full view. The images were imported into an image editing software program, resized, and rotated to the upright head position. Reference lines were constructed to assess the anteroposterior positions of the maxillary central incisors and forehead inclinations.
Results: In the control sample, the maxillary central incisors were positioned between the forehead facial axis (FFA) point and glabella in 91%, posterior to the FFA point in 8%, and anterior to the glabella in <1%. The position of the maxillary central incisors was moderately correlated with forehead inclination (r2 = 0.37). In the study sample, the maxillary central incisors were positioned between the FFA point and glabella in 34%, posterior to the FFA point in 59%, and anterior to the glabella in 7%. Maxillary central incisor position and forehead inclination were strongly correlated (r2 = 0.53). The anteroposterior maxillary incisor position relative to the forehead between the control and study groups was significantly different (P < .0001). In addition, the forehead inclination between the control and study group was significantly different (P < .05).
Conclusion: The forehead is an important landmark for anteroposterior maxillary incisor positioning for adult white male patients seeking improved facial harmony.
Keywords: anteroposterior jaw position, forehead, landmark, white male
Aim: This prospective clinical trial aims at correlating miniscrew implant (MSI) micro/macro architecture, the method of placement, and biologic markers in peri-MSI crevicular fluid (PMICF) as indicators of bone response. A comparative evaluation of surface morphology of the MSIs before placement and after retrieval defines a correlation between the architecture of the MSIs and the bone- implant contact ratio.
Methods: Two types of MSIs (hybrid and cylindric) were placed in ten patients using a split-mouth technique with the aid of a restricted random number table. Each of the MSIs was placed in the intraradicular area between the second premolar and first molar in the attached gingiva, 4 mm from the cementoenamel junction. The MSIs were immediately loaded, and PMICF was collected on days 0, 7, 14, 21, 28, and 42 and evaluated using a standard laboratory protocol. Surface morphology before placement and after retrieval of the MSI was observed using scanning electron microscopy (SEM) at a magnification of ×11, ×40, and ×1,000.
Results: Alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels observed were lower in the hybrid MSI in comparison to the cylindric MSI. For both MSIs, ALP and AST levels showed a trend of significant increase at days 0, 7, and 14 and then a significant decrease on days 21, 28, and 42. Observations from SEM showed an oxide layer over the entire surface of the bone-expanding hybrid MSI; this layer was observed only at the tip of the cylindric MSI.
Conclusions: Levels of both the diagnostic tissue destruction biologic markers ALP and AST are significantly higher in cylindric MSIs compared with hybrid MSIs, indicating a correlation to the type and method of placement of the MSI. The inflammatory markers show a definitive trend, with an elevation until day 14 and a decline after that, indicating an active inflammatory process until day 14 that could be correlated to tissue trauma. Observations from the SEM show a greater oxide layer formation in the hybrid MSI, which could imply a better bone-MSI contact ratio.
Keywords: temporary anchorage devices, bone remodeling, biologic markers, surface morphology and architecture
Aim: Enamel demineralization is considered to be the most prevalent and significant iatrogenic effect associated with fixed orthodontic treatment and can seriously jeopardize both tooth longevity and dental esthetics. This in vitro study was undertaken to compare the effectiveness of four different commercially available surface treatment medicaments for the inhibition of enamel demineralization.
Methods: Seventy-five intact maxillary premolars extracted from patients undergoing orthodontic treatment were divided into five equal groups and were subjected to one of the following protocols: no treatment (control group) or treatment with one of the following four medicaments: fluoride varnish (Fluor Protector [FP]), casein phosphopeptide-amorphous calcium phosphate (GC Tooth Mousse [TM]), calcium sodium phosphosilicate (SHY-NM), and casein phosphopeptide-amorphous calcium phosphate with fluoride (GC Tooth Mousse Plus [TMP]). All the teeth were subjected to ten Cate demineralization solution
for 96 hours and subsequently evaluated under polarized light microscopy
to obtain the mean depths of enamel demineralization. One-way analysis of variance and Bonferroni comparison tests were used to obtain statistically significant differences between the five different groups at P < .05.
Results: All four surface treatment medicaments provided statistically significant reduction
in the depths of enamel demineralization as compared with the control group.
FP provided the greatest protection of enamel surface in terms of reduction of lesion depth, followed by TMP, SHY-NM, and TM.
Conclusions: The use of these commercially available medicaments could prove to be beneficial for patients undergoing orthodontic treatment and who are at a risk for developing enamel decalcification.
Keywords: prevention, enamel demineralization, surface treatment medicaments, orthodontic treatment
Aim: This article is based on a pre- and postoperative retrospective analysis of a sample of patients affected by progenic syndrome who underwent maxillary bone repositioning by maxillomandibular osteotomies. Pre- and postoperative clinical, photographic, and cephalometric analysis are carried out to assess modifications of the nasal shape due to maxillary osteotomies.
Methods: The sample group studied was made up of 25 patients (13 women, 12 men) who underwent orthodontic-surgical treatment for correction of maxillomandibular deformities. The sample group was divided into two groups: the first (group A) was made up of patients who underwent maxillomandibular repositioning with advancement and lowering of the maxilla, and the second (group B) comprised patients who, as a consequence of surgical repositioning, had a maxilla that was advanced and raised. Surgical treatment was based on
Le Fort I and quadrangular Le Fort osteotomies.
Conclusion: Evaluation
of angular and linear measurements, derived from both photographic and cephalometric material, allowed the authors to compare the two groups of patients and the modifications of the nasal region. These results are then compared with those available from current scientific literature so as to define the predictability of nasal shape modification. In conclusion, it is inadvisable to perform rhinoplasty at the time of orthognathic surgery to correct pre-existing defects, such as a dorsal hump, a nasal base that is too wide or too narrow, a nasal pyramid deviation, or other esthetic defects resulting from orthognathic surgery.
Keywords: progenic syndrome, maxillomandibular osteotomies, cephalometric analysis
Aim: The thickness of the adhesive layer under a bracket may be an important factor that affects the final tooth position and bond strength. With increasing
use of preadjusted brackets, it is important to ensure that a consistently even layer of composite is placed under each bracket to take full advantage of bracket design and to avoid the need for compensatory bends to be placed in the archwire. Therefore, the present study is aimed at determining the optimum adhesive thickness by varying the force of application and observing the effect on the shear bond strength of orthodontic brackets.
Methods: Sixty premolars extracted for orthodontic purposes were divided into three groups of 20 samples each. Adhesive thickness was measured by varying the force of application while bonding brackets with light-cured adhesive and tested on a universal testing machine to evaluate the shear bond strength.
Results: The study showed that adhesive thickness is inversely proportional to applied force. In addition, the shear bond strength has a tendency to increase with a decrease in adhesive thickness up to a certain extent and then decrease.
Conclusion: Adhesive thickness between bracket base and tooth surface decreases with an increase in the amount of force application from 1 to 3 oz. Mean shear bond strength increases when adhesive thickness decreases from 0.99 to 0.83 mm, and then it has a tendency to decrease when adhesive thickness decreases to 0.72 mm. Optimum adhesive thickness should be considered to be 0.83 mm, which is the thickness required to achieve sufficient bond strength to prevent chances of bond failure.
Keywords: adhesive thickness, force application, shear bond strength
Aim: The aim of this study was to determine any skeletal morphologic features evident on a pretreatment lateral cephalogram that may be used to predict improvement in the sagittal relationship during functional appliance therapy in Class II patients and compare changes between cases with and without a favorable response to growth modulation.
Method: Pretreatment and postfunctional lateral cephalograms were analyzed, and the change in the ANB angle was used to determine the skeletal response to treatment with a functional appliance. Based on the change in the ANB angle, the patients were divided into two groups of 12 patients each. Comparisons were made between the mean pretreatment (T1) cephalometric parameters of group I (skeletal) and group II (nonskeletal) to assess any pretreatment parameters that were significantly different between the groups. Changes due to functional appliance therapy from the pretreatment (T1) to postfunctional (T2) stage was measured as T2-T1
in both groups. The mean changes seen in group I and group II were then compared to assess the difference between changes brought about by growth modulation using functional appliances. Comparative statistical analysis of the data was done using one-way analysis of variance F test.
Results and conclusion: This study showed that not all cases respond favorably to growth modulation. The pretreatment parameters that correlated to a favorable response were low mandibular plane angle, low basal plane angle, and a high Jarabak ratio. In those cases that responded favorably, the changes seen were an increase in Co-Go (ramus height), decrease in overjet, increase in SNB, and increase in the Jarabak ratio.
Keywords: growth modulation, growth pattern, prediction of growth, case selection, functional appliance, success prediction
Aim: In this study the color stability of five commercially available orthodontic clear elastic ligatures daily exposed to a staining agent (red wine) was investigated.
Methods: The commercial brands tested were 3M Unitek, Abzil, American Orthodontics, Dentsply GAC, and Morelli. Baseline color readings (Commission Internationale de l'Eclairage [CIE] L*a*b* parameters) of 20 ligatures for each brand were carried out using a spectrophotometer. The ligatures were divided in two groups (n = 10): one group remained immersed in distilled water (control) throughout the period, while the other group was daily exposed to red wine (1 hour of immersion). Immersion media were daily renewed. Successive color readings were carried out after 7, 14, 21, and 28 days, and the chromatic variations calculated. Color variation data were analyzed by two-way repeated measures analysis of variance and Student- Newman-Keuls test (P < .05).
Results: Storage in water increased staining until 14 days, and color receded after this period, irrespective of the brand. After 28 days of immersion in water, no significant difference among the commercial brands was observed. For the groups exposed to red wine, a significant increase in staining over the course of time was detected, irrespective of the brand. Ligatures from GAC and Morelli showed higher staining than the other materials, irrespective of the evaluation time. Ligatures from 3M Unitek and American generally showed lower pigmentation than the other brands.
Conclusion: Exposure to a staining agent, cumulative exposure time, and commercial brand are factors that influence the color stability of clear elastic ligatures.
Keywords: CIE L*a*b*, clear ligatures, spectrophotometer, staining, translucency
Aim: The present study aimed to measure the magnitude of the collum angle (crown-root angulation) of maxillary central incisors present in Class II, division 2 malocclusion and to relate the changes in its magnitude with variations in the lower lip line.
Methods: A set of 120 conventional lateral cephalograms were selected and divided into three groups of 40 each based on the type of malocclusion presented: Class II, division 2 (group 1); Class II, division 1 (group 2); and Class I (group 3). The collum angle of the maxillary central incisor was measured, and the lower lip line was recorded.
Results: Analysis of variance (ANOVA) revealed that the mean collum angle was statistically significantly different in the three groups. The mean collum angle was greatest in Class II, division 2 malocclusion (group 1). The mean collum angles were 3.24 ± 4.69 degrees, 0.95 ± 1.06 degrees, and 1.05 ± 1.50 degrees in groups 1, 2, and 3 respectively. In χ2 test comparison of the location of the lower lip line (incisal, middle, or apical third of the central incisor) among the three groups, the lower lip line was found to contact the middle third of the central incisor most frequently in Class II, division 2 malocclusion. ANOVA followed by Tukey honestly significant difference (HSD) test showed that the mean collum angle is significantly increased when the lower lip is in the middle third (P < .05) of the central incisor.
Conclusion: Variations in magnitude of the collum angle with the change in the lower lip line suggest a probable etiologic role of the lower lip line in the development of the collum angle.
Keywords: collum angle, lower lip line
Aim: The purpose of this study was to investigate the salivary concentration
of nickel and chromium of patients undergoing orthodontic treatment.
Methods: In this study 32 patients who presented to the orthodontic clinic were selected. The salivary samples were taken from the patients in four stages: before appliance placement and 20 days, 3 months, and 6 months following appliance placement. The salivary samples were collected in a plastic tube and were stored in the freezer before analysis. The samples were then transferred to the laboratory, and the amounts of metals were determined by graphite furnace atomic absorption spectrometry with an autosampler. Each sample was analyzed three times, and the average was reported.
Results: It was found that the average amount of nickel in the saliva 20 days after appliance placement
was 0.8 µg/L more than before placement. Also, the amount of salivary nickel
20 days after the appliance placement was more than at the other stages, but the differences were not significant. The average amount of chromium in the saliva was found to be between 2.6 and 3.6 µg/L. The amount of chromium at
all stages after appliance placement was more than before, but the differences between the chromium levels of saliva at all stages were not significant.
Conclusion: There was no significant difference in the average amount of salivary nickel and chromium of patients at various stages of orthodontic appliance placement.
Keywords: chromium, nickel, salivary samples, corrosion
Aim: The purpose of the present study was to evaluate the shear bond strength of orthodontic brackets bonded to porcelain following etching with erbium- doped yttrium aluminum garnet (Er:YAG) laser compared with 9.6% hydrofluoric acid (HF).
Methods: A total of 100 porcelain disk samples were divided into four groups, and after removing their glazed layer, the first group was etched with 9.6% HF, and the other three groups were etched with Er:YAG lasers of 1.6, 2, and 3.2 W, respectively. After application of silane on the disk surfaces, central incisor brackets were bonded with composite on the disks. The disks were mounted on an acrylic stand for measuring the shear bond strengths. The shear bond strengths were measured by a testing machine.
Results: The mean shear bond strength in the laser group with power of 1.6 W (7.88 MPa) was more than that
of the HF (7.4MPa), 2-W power (7.52 MPa), and 3.2-W power (7.45 MPa) groups, but this difference was not statistically significant. Examination with an electron microscope showed different patterns of etching by HF and laser. Also, etching by laser and HF had not resulted in cracks on the porcelain surface.
Conclusion: Er:YAG laser can be a suitable method for bonding of orthodontic brackets to porcelain surfaces.
Keywords: laser, shear bond strength, hydrofluoric acid, Er:YAG
This clinical report presents a case treated by a currently available
customized orthodontic treatment system. The use of patient-specific brackets, indirect bonding transfer devices, and customized archwires decreases treatment and chairside time, making orthodontic cases more predictable, accurate, and efficient. The need for time-consuming adjustments is greatly reduced, and appliance customization further facilitates the achievement of the final desired occlusion from the first day of treatment.
Keywords: customized appliances, Insignia
Management of severe rotation poses a great challenge for the orthodontist, especially when cortical anchorage occurs. The conventional methods require excessive treatment time, rely on patient compliance, and can
cause root resorption. A groundbreaking new procedure developed by Wilcko et al, which is actually a modification of the conventional corticotomy procedure, amalgamates the orthodontic mechanics, alveolar decortications, and augmentation procedure to make treatment time three to four times faster than conventional orthodontic techniques. This procedure uses the dynamics of bone physiology and redirects the emphasis in tooth movement to the manner in which supporting bone responds to orthodontic forces applied to the tooth. This article includes a case report in which the technique is used on a patient who has a severely rotated mandibular left canine.
Keywords: corticotomy, accelerated osteogenic orthodontics, Kole's corticotomy, canine derotation, NiTi wire, regional acceleratory phenomenon
Aim: The aim of this study was to evaluate the effect of different methods of ligation in tie configurations on friction in dry and wet conditions.
Methods:
Four methods of ligations were used: regular round tie, figure eight, twist, and diagonal. Materials used were Alastik (3M Unitek), Power O module (ORMCO), O-ring ligatures (JES), stainless steel ligatures (TP Orthodontics), 0.019 × 0.025-inch straight-length stainless steel archwires and stainless steel MBT 0.022-inch slot brackets (3M Unitek).
Results: Figure eight ligation had the highest friction, followed by round, twist, and diagonal ligation, in the descending order. Comparisons were statistically significant with a 100-g load. Dry group samples had higher friction than the wet group. These comparisons were statistically significant with a 50-g load.
Conclusions: The study concluded that figure eight ligation had the highest friction, and diagonal ligation produced the least friction. Among the dry and wet groups, lubrication showed significant reduction in friction.
Keywords: ligation methods, sliding mechanics, friction
Aims: To survey retention protocols and need for practical retention guidelines among orthodontists in Norway and to compare the results with similar studies in other countries.
Methods: A questionnaire was mailed to all members of
the Norwegian Association of Orthodontists. It included questions about their background and their current retention protocol, as well as their perceived need for common retention guidelines.
Results: The response rate was 77.7% (69.3% males and 30.7% females). The most common maxillary retainer was a combination of a fixed and removable retainer, followed by a clear thermoplastic retainer. In the mandible, a fixed retainer bonded to all anterior teeth was most common (66.4%). Retention in the maxilla lasted 2 to 3 years (34.7%) or 3 to 5 years (23.8%). In the mandible, 41.5% of the orthodontists left the retainer in place for >5 years. When retention lasted more than 3 years, 70% of the orthodontists left the responsibility for retainer checkups to the patients or the general practitioners. The main reason for choosing a certain retention protocol was clinical experience (57.4%). Only 3.5% of the orthodontists based their protocols on information from the literature. Half
of the orthodontists, significantly women, expressed a need for common retention guidelines.
Conclusions: In Norway, bonded retainers alone were reported to be most commonly used in the mandible, while bonded retainers used in combination with a removable retainer appear to be the most commonly used appliances in the maxilla. This is similar to the most frequently used retainers in other countries, but there are disparities in duration and follow-up protocols. Most female orthodontists desire common retention guidelines.
Keywords: retention protocols, orthodontic retainers
A new way to upright the mandibular second molar is described. The principles of the Loca system, originally used for molar distalization, are employed in the mandibular arch.
Keywords: tooth impaction, impacted second molars, molar uprighting, Loca system, heat-activated NiTi, superelastic NiTi
The application of a combined surgical-orthodontic procedure for the treatment of major facial deformities (eg, asymmetries) and associated malocclusions
has become an increasingly prevalent treatment modality over the past few decades. Development of sound conjoint treatment principles made possible the correction of skeletal and dental dysplasias that were unyielding to either surgical or orthodontic treatment alone. The presence and severity of dentofacial asymmetries has been the subject of many commentaries and investigations. Treatment of facial asymmetry has always been a challenge with respect to the cause and the rationale behind the corrective procedures adopted. This case report describes a 23-year-old male patient whose chief complaint was attributed solely to the clinically discernible facial asymmetry. A combined orthodontic and surgical approach was done to correct both the dental and skeletal asymmetry. The reasons for selecting this treatment protocol and the 5-year postretention stability of the final results obtained are highlighted in this report.
Keywords: facial asymmetry, orthognathic surgery, retention
This article describes the orthodontic treatment of a young woman with a Class II malocclusion and maxillomandibular prognathism. One orthodontic mini- implant was placed in the posterior area of the palate to provide anchorage for
a transpalatal arch. The force for molar distalization was applied using an elastic chain from the lever arm inserted on the transpalatal arch to the mini-implant. Two sliding jigs were applied buccally as a complement for Class II malocclusion correction. This system created an efficient mechanotherapy for maxillary molar distalization. The active treatment period was 19 months. Normal overjet and reduction of maxillomandibular prognathism were obtained, and labial balance was improved.
Keywords: orthodontic mini-implant, Class II malocclusion correction, molar distalization appliance
Osteogenesis imperfecta is a bone disorder in which three factors that influence bone strength (quality, mass, and geometry of osseous tissue) are affected. Pneumatization refers to the development of air-filled cavities inside the bone. Knowledge about these air-filled cavities provides valuable information for understanding the diagnosis and spread of various pathologic entities like hemangiomas, giant cell tumors, eosinophilic granulomas, and even metastatic tumor deposits. This paper presents a case in which radiologic, clinical, biochemical, and karyotypic evaluations lead to a diagnosis of osteogenesis imperfecta.
Keywords: karyotyping, osteogenesis imperfecta, pneumatization
This report describes the use of the miniscrew as orthodontic anchorage in maxillary protrusion with a spaced arch and midline deviation in a 16-year- old female patient. In cases with midline deviation, a cant in the maxillary occlusal plane is often observed. Thus, the authors used the miniscrew to control the vertical dimension, thereby flattening the maxillary occlusal plane, and to close and retract the incisors to improve her convex profile. Effective incisor intrusion to correct the deep overbite was also observed.
In addition, functional evaluation by a 6-degrees-of-freedom jaw movement recording system was performed. Significant improvement in the jaw movement was observed during maximum opening and lateral excursion during the retention phase. The authors suggest that miniscrews are effective in correcting midline deviation due to maxillary occlusal cant and intrusion and retraction of incisors, and may result in favorable functional movement of the jaw.
Keywords: occusal cant, maxillary protrusion, midline discrepancy, spaced arch, miniscrew
Zimmermann-Laband syndrome (ZLS) is a rare autosomal disorder characterized by gingival fibromatosis, abnormalities of the nose and/or ears, hypoplasia
of the nails or terminal phalanges of the hands and feet, hyperextensibility
of joints, hepatosplenomegaly, hirsutism, and intellectual disability. The characteristics of the syndrome are highly variable and complicated. This paper reports a case of ZLS and the clinical manifestations encountered in relation to the current available literature. The comprehensive management of the patient's dentition is described, focusing on the orthodontic and surgical considerations clinicians should be aware of when treating patients with the syndrome.
Keywords: Zimmerman-Laband syndrome, fibromatosis, gingival phenotype, treatment outcome, humans
Aim: Rapid correction of developing Class III malocclusion in pediatric patients using a method with decreased reliance on patient compliance and increased patient comfort.
Method: The modified fixed nanobite tandem appliance (MFNTA) consists of three components, two fixed and one removable. The maxillary fixed appliance consists of a nickel-titanium fixed maxillary expander and a soldered buccal arm used for Class III elastic traction. The mandibular appliance consists of modified fixed nanobite and buccal headgear tubes welded to the mandibular first molar band
for facebow attachment.
Result: Pre- and posttreatment records revealed significant skeletal improvement without increase in the vertical dimension and marked improvement in facial balance and esthetics.
Conclusion: MFNTA has the potential to be an effective tool in the treatment of developing Class III malocclusion and relief of the psychologic trauma caused by an anterior crossbite.
Keywords: Class III malocclusion, midface deficiency, MFNTA
The aim of this report is to illustrate treatment mechanics for torque control in lingual mechanotherapy using a lever arm and transpalatal arch (TPA) tab system during en masse retraction of anterior teeth. An 18-year-old female with bimaxillary dentoalveolar proclination with crowding was treated with
a lever arm-TPA tab system. The retraction tabs bent into the TPA placed across the maxillary second molars were used as anchorage. The retraction force on the maxillary anterior teeth was applied using lever arm hooks soldered between the lateral incisors and canines on a lingual mushroom archwire. By applying a retraction force to the lever arm hooks, the maxillary anterior teeth experienced greater palatal root movement as compared to the conventional retraction forces applied at the crown level. The tabs, placed high in the TPA, produced a distal tipping moment on the maxillary second molars, reinforcing their anchorage. The retraction force applied to the long lever arm hooks from the TPA tabs at the level of center of resistance (CRes) of anterior and posterior teeth is advantageous mainly in two aspects. First, it reinforces the anchorage, and second, it favors the palatal root movement of anterior teeth, thus obtaining better control over the torque during en masse retraction.
Keywords: transpalatal arch, center of resistance, center of rotation, lever arms
Aim: The purpose of this prospective study was to determine the number of contacts in centric occlusion during retention with modified and full-coverage thermoplastic Essix retainers.
Methods: This research was based on 36 patients who were randomly assigned to wear either modified (18 patients) or full- coverage (18 patients) Essix retainers. Silicone-based bite registrations were used to record occlusal contacts at the beginning (T1), end of full-time (6 months; T2), and end of night-time (3 months; T3) wear of retainers. The occlusal contacts determined in treated patients were compared with the values of 18 untreated "normal" Class I subjects. Bonferroni-adjusted Wilcoxon and Kruskal-Wallis tests were used to evaluate intra- and intergroup differences.
Results: Total posterior contacts increased significantly at T3 compared to T1 and T2 only
in the modified Essix group. Non-ideal and total contacts on premolars, non- ideal and actual contacts on first molars, and actual contacts on second molars increased significantly at T3 in the modified Essix group. No significant increase was determined in the final total posterior contacts in the full-coverage Essix group. Actual contacts on premolars and first molars and total posterior actual contacts were significantly greater at T3 in the modified Essix group compared to the full-coverage Essix Group. Also the number of final posterior ideal contacts in the modified Essix group was greater than in the normal sample. Total anterior contacts decreased significantly in the modified Essix group, whereas they increased significantly in the full-coverage Essix group.
Conclusions: Increase in posterior contacts was achieved only during night-time wear of modified Essix retainers.
Keywords: thermoplastic retainer, Essix retainer, vacuum-formed retainer, occlusal contacts, retention
This manuscript describes the use of a tooth indicated for extraction due
to orthodontic reasons as an anchorage aid to receive undesirable side effects caused by orthodontic uprighting of a contralateral molar tooth. The mandibular right second molar was mesially tipped as a result of loss of the adjacent first molar. Since the treatment plan involved extraction of the mandibular left first premolar, undesirable side effects associated with the molar uprighting movement were transferred to this tooth. Once the second molar was vertical, the premolar was extracted and the treatment continued. The results suggest that treatment time can be reduced if undesirable orthodontic mechanical side effects can be directed to a tooth whose extraction is indicated.
Keywords: orthodontic anchorage procedures, tooth movement
A plate that incorporates a Ti-Ni alloy wire can rapidly correct scissors bite. This article describes its use in the successful treatment of scissors bite. A female patient aged 7 years, 5 months with mixed dentition presented with
a Class I molar relationship, Class I skeletal pattern, and average Frankfort-mandibular plane angle. The maxillary right central incisor was in a crossbite. A unilateral posterior scissors bite was also present on the left side. The plate was fitted and prescribed for nighttime wear. Positive overjet was achieved after 1 month of treatment. The posterior scissors bite was corrected after 3 months of treatment, and the midline shift was ameliorated. Because a Ti-Ni wire maintained a weak continuous force, the treatment period was minimized.
Keywords: scissors bite, Ti-Ni wire, mixed dentition, removable plate
Aim: Distalization of the maxillary molars is an important treatment option for the correction of Class II malocclusions. The purposes of this study were to introduce the clinical application of the indirect Palatal miniscrew Anchorage and Distalization Appliance (iPanda) and to describe the dental and skeletal effects obtained with this innovative appliance.
Methods: Pretreatment (TO), post- distalization (T1), and posttreatment (T2) lateral cephalometric radiographs and dental casts of 20 consecutively treated adult patients (mean age 23.2 ± 4.7 years) with Class II molar relationship were analyzed. All patients were treated with the iPanda for maxillary molar distalization. The iPanda was anchored on a pair of midpalatal miniscrew implants to deliver the distalizing force to the maxillary first molars. The iPanda was the only appliance used during the distalization phase of treatment. A paired t test analysis was used to statistically assess the effects of treatment.
Results: A Class I molar relationship was obtained in a mean period of 3.2 ± 0.6 months. Cephalometric analysis demonstrated that the maxillary first molars were significantly distalized by an average 4.5 ± 1.5 mm (P < .001) and were intruded by a mean of 1.0 mm ± 0.8 mm (P <. 05). No significant change in the inclination of the first molars was observed. No significant change in the mandibular plane was observed. Dental model analysis demonstrated an asymmetric pattern of distalization between right (4.5 ± 2.2 mm) and left (3.1 ± 2.1 mm) first molars. The transverse width of the dental arch was maintained. No significant rotation of the first molars was observed.
Conclusions: This study demonstrated that the innovative iPanda is effective to bodily distalize the maxillary molars into a Class I molar relationship and to provide maximum anchorage.
Keywords: Miniscrew implants, Molar distalization, appliances