Search

• Routine alignment with fixed mechanics or aligners is indeterminate mechanics. • Aligned arches can be moved predictably with determinate mechanics. • Temporary skeletal anchorage devices are retromolar implants, inter-radicular miniscrews, and extra-alveolar bone screws in the infrazygomatic crest and mandibular buccal shelf. • Skeletal Class III malocclusion can be corrected with infrazygomatic crest and mandibular buccal shelf retraction of the lower arch, but only mandibular buccal shelf anchorage decreases facial height. • Retraction and posterior rotation of the mandibular arch with mandibular buccal shelf anchorage reverses the etiology of Class III open bite malocclusion. • The axis of rotation for the lower arch, as calculated with finite element analysis, is through the upper root of the canines. • Periodontal ligament stress <5 kPa avoids necrosis and results in tooth movement of about 1 mm per month, which is near the physiologic rate of bone resorption during remodeling. Routine alignment with fixed appliances and aligners is indeterminate mechanics because equilibrium equations are only applicable to two abutments: teeth, segments, or arches. Orthodontists must depend on compliance and resilience of materials (archwires and aligners) for initial alignment. However, stabilized segments and arches are "large multirooted teeth" that can be moved with determinate mechanics using temporary skeletal anchorage devices. Temporary skeletal anchorage devices have advanced from retromolar implants and inter-radicular miniscrews to extra-alveolar bone screws placed in the basilar bone buccal to the first molars: mandibular buccal shelf and infrazygomatic crest. Extra-alveolar anchorage is determinate mechanics to move teeth, segments, and arches. Retraction and rotation of the lower arch reverses the etiology of Class III open bite malocclusion to correct severe skeletal dysplasia with no extractions or orthognathic surgery. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to assess the 6-month survival (success) rate for infrazygomatic crest (IZC) bone screws relative to patient age, insertion angle, sinus penetration, and terminal insertion torque.Methods: One hundred consecutive patients (27 males, 73 females; mean age 25.8 years; age range, 11.0-53.8 years) received IZC temporary anchorage devices (TADs) bilaterally (n = 200). Each TAD was routinely loaded with up to 14 oz (397 g or 389 cN), reactivated monthly, and followed for 6 months. Terminal insertion torque was measured, and radiographs were assessed to determine the length of the TAD engaged in bone and depth of penetration into the maxillary sinus.Results: Compared with nonpenetrating IZC TADs, the mean results for the 96 (48%) TADs that did penetrate the sinus were: 3.23 mm of sinus penetration, 21.3% decrease in terminal insertion torque, and 31.5% less bone contact at the TAD osseous interface. Perforation prevalence increased with age from 35.7% (11-19 years) to 62.5% (>30 years) (P <0.01). Terminal insertion torque increased from 11-19 years to 20-29 years because of increasing bone density with age but then decreased at >30 years because of increased incidence of sinus penetration (P <0.05). Sinus penetration had no significant effect on IZC TAD survival. About 5% of the devices did fail when the final insertion torque was significantly (P <0.05) decreased to 7.37 N-cm compared with the mean torque of 11.63 N-cm for successful TADs.Conclusions: Both sinus perforation and IZC bone quality increased with age. Sinus penetration did not significantly affect the 6 month survival rate of IZC TADs because the loss of bone quantity at the interface was offset by the age-related increase in bone quality at the IZC site. [ABSTRACT FROM AUTHOR]

To assess the mechanical environment for three fixed appliances designed to retract the lower anterior segment. A cone-beam computed tomography scan provided three-dimensional morphology to construct finite element models for three common methods of lower anterior retraction into first premolar extraction spaces: (1) canine retraction with a T-loop, (2) en-masse space closure with the power-arm on the canine bracket (PAB), and (3) power-arm directly attached to the archwire mesial to the canine (PAW). Half of the symmetric mandibular arch was modeled as a linear, isotropic composite material containing five teeth: central incisors (L1), lateral incisor (L2), canine (L3), second premolar (L4), and first molar (L5). Bonded brackets had 0.022-in slots. Archwire and power-arm components were 0.016 × 0.022 in. An initial retraction force of 125 cN was used for all three appliances. Displacements were calculated. Periodontal ligament (PDL) stresses and distributions were calculated for four invariants: maximum principal, minimum principal, von Mises, and dilatational stresses. The PDL stress distributions for the four invariants corresponded to the displacement patterns for each appliance. T-loop tipped the canine(s) and incisors distally. PAB rotated L3 distal in, intruded L2, and extruded L1. PAW distorted the archwire resulting in L3 extrusion as well as lingual tipping of L1 and L2. Maximum stress levels in the PDL were up to 5× greater for the PAW than the T-loop and PAB methods. T-loop of this type is more predictable because power-arms can have rotational and archwire distortion effects that result in undesirable paths of tooth movement. [ABSTRACT FROM AUTHOR]

Objectives: To compare failure rates for stainless steel (SS) and titanium alloy (TiA) bone screws (BSs) placed in the infrazygomatic crest (IZC). Materials and Methods: A total of 386 consecutive patients (76 male, 310 female; mean age 24.3 years, range 10.3-59.4 years) received IZC BSs (SS or TiA) via a double-blind, split-mouth design. BSs penetrated attached gingiva (AG) or moveable mucosa (MM) with 5 mm of soft tissue clearance. All BSs were immediately loaded and reactivated monthly with ≤14 oz (397 g or 389 cN) applied directly to the upper archwire bilaterally for 6 months to retract the maxilla to correct Class II or bimaxillary protrusion. Results: Of the 772 devices, there were 49 (6.3%) failures: 27 SS (7.0%) and 22 TiA (5.7%). The 1.3% difference was not statistically significant (P = .07). There was no significant relationship between SS or TiA failures relative to (1) right vs left side, (2) unilateral vs bilateral, or (3) age at failure. Significantly (P < .05) increased failure rates were noted for SS screws in only two subgroups: AG site (7.4%) and right side (7.8%). Unilateral failure occurred in 21 patients (5.4%), and bilateral failures occurred in 14 of the total 772 patients (1.8%). Conclusions: The overall success rate of 93.7% indicates that both SS and TiA are clinically acceptable for IZC BSs. [ABSTRACT FROM AUTHOR]

A 33-year-old woman had a chief complaint of difficulty chewing, caused by a constricted mandibular arch and a unilateral full buccal crossbite (scissors-bite or Brodie bite). She requested minimally invasive treatment but agreed to anchorage with extra-alveolar temporary anchorage devices as needed. Her facial form was convex with protrusive but competent lips. Skeletally, the maxilla was protrusive (SNA, 86°) with an ANB angle of 5°. Amounts of crowding were 5 mm in the mandibular arch and 3 mm in the maxillary arch. The mandibular midline was deviated to the left about 2 mm, which was consistent with a medially and inferiorly displaced mandibular right condyle. Ectopic eruption of the maxillary right permanent first molar to the buccal side of the mandibular first molar cusps resulted in a 2-mm functional shift of the mandible to the left, which subsequently developed into a full buccal crossbite on the right side. Treatment was a conservative nonextraction approach with passive self-ligating brackets. Glass ionomer bite turbos were bonded on the occlusal surfaces of the maxillary left molars at 1 month into treatment. An extra-alveolar temporary anchorage device, a 2 × 12-mm OrthoBoneScrew (Newton A, HsinChu City, Taiwan), was inserted in the right mandibular buccal shelf. Elastomeric chains, anchored by the OrthoBoneScrew, extended to lingual buttons bonded on the lingually inclined mandibular right molars. Cross elastics were added as secondary uprighting mechanics. The maxillary right bite turbos were reduced at 4 months and removed 1 month later. At 11 months, bite turbos were bonded on the lingual surfaces of the maxillary central incisors, and an OrthoBoneScrew was inserted in each infrazygomatic crest. The Class II relationship was resolved with bimaxillary retraction of the maxillary arch with infrazygomatic crest anchorage and intermaxillary elastics. Interproximal reduction was performed to correct the black interdental spaces and the anterior flaring of the incisors. The scissors-bite and lingually inclined mandibular right posterior segment were sufficiently corrected after 3 months of treatment to establish adequate intermaxillary occlusion in the right posterior segments to intrude the maxillary right molars. The anterior bite turbos opened space for extrusion of the posterior teeth to level the mandibular arch, and the infrazygomatic crest bone screws anchored the retraction of the maxillary arch. In 27 months, this difficult malocclusion, with a Discrepancy Index score of 25, was treated to a Cast-Radiograph Evaluation score of 22 and a pink and white esthetic score of 3. [ABSTRACT FROM AUTHOR]

Maxillary constriction is routinely addressed with rapid maxillary expansion (RME). However, the heavy forces delivered by most RME appliances to expand the palate may lead to deleterious effects on the teeth and supporting tissues. The objective of this study was to explore a more physiologic maxillary expansion with light continuous force. Materials and Methods: Twenty 6-week-old Sprague-Dawley rats were equally divided into experimental (EXPT) and control (CTRL) groups. A custom-fabricated archwire expansion appliance made from 0.014-inch copper-nickel-titanium wire was activated 5 mm and bonded to the maxillary molar segments of animals in the EXPT group for 21 days. The force applied to each maxillary segment was 5 cN. Microfocus x-ray computed tomography and histological analyses were used to compare the tooth movement and bone morphology in the midpalatal suture and buccal aspect of the alveolar process between the EXPT and CTRL groups. Descriptive statistics (mean 6 standard error of the mean) and nonparametric statistical tests were used to compare the outcomes across groups. Results: Compared to the CTRL group, there was a statistically significant increase in buccal tooth movement and expansion of the midpalatal suture in the EXPT group. There was no difference in the bone morphologic parameters between groups. The mineral apposition rate was increased on the buccal surface of the alveolar process in the EXPT group. Conclusions: Application of light, continuous force resulted in maxillary osseous expansion due to bilateral sutural apposition and buccal drift of the alveolar processes. This animal experiment provides a more physiologic basis for maxillary expansion. [ABSTRACT FROM AUTHOR]

A 36-year-old woman with good periodontal health sought treatment for a compensated Class II partially edentulous malocclusion associated with a steep mandibular plane (SN-MP, 45°), 9 missing teeth, a 3-mm midline discrepancy, and compromised posterior occlusal function. She had multiple carious lesions, a failing fixed prostheses in the mandibular right quadrant replacing the right first molar, and a severely atrophic edentulous ridge in the area around the mandibular left first and second molars. After restoration of the caries, the mandibular left third molar served as anchorage to correct the mandibular arch crowding. The mandibular left second premolar was retracted with a light force of 2 oz (about 28.3 cN) on the buccal and lingual surfaces to create an implant site between the premolars. Modest lateral root resorption was noted on the distal surface of the mandibular left second premolar after about 7 mm of distal translation in 7 months. Six months later, implants were placed in the mandibular left and right quadrants; the spaces were retained with the fixed appliance for 5 months and a removable retainer for 1 month. Poor cooperation resulted in relapse of the mandibular left second premolar back into the implant site, and it was necessary to reopen the space. When the mandibular left fixture was uncovered, a 3-mm deep osseous defect on the distobuccal surface was found; it was an area of relatively immature bundle bone, because the distal aspect of the space was reopened after the relapse. Subsequent bone grafting resulted in good osseous support of the implant-supported prosthesis. The relatively thin band of attached gingiva on the implant at the mandibular right first molar healed with a recessed contour that was susceptible to food impaction. A free gingival graft restored soft tissue form and function. This severe malocclusion with a discrepancy index value of 28 was treated to an excellent outcome in 38 months of interdisciplinary treatment. The Cast-Radiograph Evaluation score was 13. However, the treatment was complicated by routine relapse and implant osseous support problems. Retreatment of space opening and 2 additional surgeries were required to correct an osseous defect and an inadequate soft tissue contour. Orthodontic treatment is a viable option for creating implant sites, but fixed retention is required until the prosthesis is delivered. Bone augmentation is indicated at the time of implant placement to offset expected bone loss. Complex restorative treatment may result in routine complications that are effectively managed with interdisciplinary care. [ABSTRACT FROM AUTHOR]

It is usually desirable to recover horizontally impacted mandibular molars. Impacted third molars may also be valuable dental units if the adjacent first or second molars are compromised or missing. Uprighting horizontally impacted third molars prior to extraction may be a wise measure to avoid damaging the second molar and its periodontium and inferior alveolar nerve during a surgical extraction procedure. However, uprighting horizontally impacted molars is complex and/or difficult for the orthodontist and oral surgeon. Lin (2011 [1] ) reviewed six different methods for recovering deeply impacted molars, and concluded that the most reliable and effective approach was to surgically expose the deeply impacted molars and upright them with traction via a ramus screw (Lee et al., 2014 [2] ; Lin et al., 2014 [3] ). From a biomechanics perspective, the anterior ramus of the mandible is an ideal location for an anchorage screw. However, this anatomic area appears to be a high risk site because it is covered with thick, mobile soft tissue (Lin et al., 2015 [4] ). This article is aimed at increasing the confidence of clinicians relative to the use of ramus screws by reviewing the treatment planning, surgical procedures, orthodontic mechanics, and reliability of the procedure. [ABSTRACT FROM AUTHOR]

A 12-year-old girl presented with a Class II Division 1 malocclusion, complicated by a complete transposition of the maxillary left canine into the position normally occupied by the left lateral incisor. Dental and medical histories were noncontributory. Brackets were bonded on all maxillary teeth, from first molar to first molar, except for the left lateral incisor. Because the lateral incisor was not engaged on the archwire, the tooth was free to physiologically move out of the path of canine root movement. To prepare the site for canine retraction, a coil spring was used to open space between the left central incisor and the first premolar. A 2 × 12-mm stainless steel miniscrew was placed in the infrazygomatic crest, labial to the mesiodistal cusp of the maxillary left first molar. A 0.019 × 0.025-in titanium-molybdenum alloy T-loop, anchored by the miniscrew, was used to retract the canine root over the labial surface of the root of the distally positioned lateral incisor. In 24 months, this difficult malocclusion, with a Discrepancy Index score of 18, was treated to a Cast-Radiograph Evaluation score of 26. [ABSTRACT FROM AUTHOR]

A man, aged 28 years 9 months, came for an orthodontic consultation for a skeletal Class III malocclusion (ANB angle, -3°) with a modest asymmetric Class II and Class III molar relationship, complicated by an anterior crossbite, a deepbite, and 12 mm of asymmetric maxillary crowding. Despite the severity of the malocclusion (Discrepancy Index, 37), the patient desired noninvasive camouflage treatment. The 3-Ring diagnosis showed that treatment without extractions or orthognathic surgery was a viable approach. Arch length analysis indicated that differential interproximal enamel reduction could resolve the crowding and midline discrepancy, but a miniscrew in the infrazygomatic crest was needed to retract the right buccal segment. The patient accepted the complex, staged treatment plan with the understanding that it would require about 3.5 years. Fixed appliance treatment with passive self-ligating brackets, early light short elastics, bite turbos, interproximal enamel reduction, and infrazygomatic crest retraction opened the vertical dimension of the occlusion, improved the ANB angle by 2°, and achieved excellent alignment, as evidenced by a Cast Radiograph Evaluation score of 28 and a Pink and White dental esthetic score of 3. [ABSTRACT FROM AUTHOR]

Introduction: In the absence of adequate animal or in-vitro models, the biomechanics of human malocclusion must be studied indirectly. Finite element analysis (FEA) is emerging as a clinical technology to assist in diagnosis, treatment planning, and retrospective analysis. The hypothesis tested is that instantaneous FEA can retrospectively simulate long-term mandibular arch retraction and occlusal plane rotation for the correction of a skeletal Class III malocclusion.Methods: Seventeen published case reports were selected of patients treated with statically determinate mechanics using posterior mandible or infrazygomatic crest bone screw anchorage to retract the mandibular arch. Two-dimensional measurements were made for incisor and molar movements, mandibular arch rotation, and retraction relative to the maxillary arch. A patient with cone-beam computed tomography imaging was selected for a retrospective FEA.Results: The mean age for the sample was 23.3 ± 3.3 years; there were 7 men and 10 women. Mean incisor movements were 3.35 ± 1.55 mm of retraction and 2.18 ± 2.51 mm of extrusion. Corresponding molar movements were retractions of 4.85 ± 1.78 mm and intrusions of 0.85 ± 2.22 mm. Retraction of the mandibular arch relative to the maxillary arch was 4.88 ± 1.41 mm. Mean posterior rotation of the mandibular arch was -5.76° ± 4.77° (counterclockwise). The mean treatment time (n = 16) was 36.2 ± 15.3 months. Bone screws in the posterior mandibular region were more efficient for intruding molars and decreasing the vertical dimension of the occlusion to close an open bite. The full-cusp, skeletal Class III patient selected for FEA was treated to an American Board of Orthodontics Cast-Radiograph Evaluation score of 24 points in about 36 months by en-masse retraction and posterior rotation of the mandibular arch: the bilateral load on the mandibular segment was about 200 cN. The mandibular arch was retracted by about 5 mm, posterior rotation was about 16.5°, and molar intrusion was about 3 mm. There was a 4° decrease in the mandibular plane angle to close the skeletal open bite. Retrospective sequential iterations (FEA animation) simulated the clinical response, as documented with longitudinal cephalometrics. The level of periodontal ligament stress was relatively uniform (<5 kPa) for all teeth in the mandibular arch segment.Conclusions: En-masse retraction of the mandibular arch is efficient for conservatively treating a skeletal Class III malocclusion. Posterior mandibular anchorage causes intrusion of the molars to close the vertical dimension of the occlusion and the mandibular plane angle. Instantaneous FEA as modeled here could be used to reasonably predict the clinical results of an applied load. [ABSTRACT FROM AUTHOR]

Objective: To compare the initial failure rate (≤4 months) for extra-alveolar mandibular buccal shelf (MBS) miniscrews placed in movable mucosa (MM) or attached gingiva (AG). Materials and Methods: A total of 1680 consecutive stainless steel (SS) 2 × 12-mm MBS miniscrews were placed in 840 patients (405 males and 435 females; mean age, 16 ± 5 years). All screws were placed lateral to the alveolar process and buccal to the lower first and second molar roots. The screw heads were at least 5 mm superior to the soft tissue. Loads from 8 oz–14 oz (227 g–397 g, 231–405 cN) were used to retract the mandibular buccal segments for at least 4 months. Results: Overall, 121 miniscrews out of 1680 (7.2%) failed: 7.31% were in MM and 6.85% were in AG (statistically insignificant difference). Failures were unilateral in 89 patients and bilateral in 16. Left side (9.29%) failures was significantly greater (P < .001) compared with those on the right (5.12%). Average age for failure patients was 14 ± 3 years. Conclusion: MBS miniscrews were highly successful (approximately 93%), but there was no significant difference between placement in MM or AG. Failures were more common on the patient's left side and in younger adolescent patients. Having 16 patients with bilateral failures suggests that a small fraction of patients (1.9%) are predisposed to failure with this method. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between root resorption (RR) and bone turnover in two different types of tooth movement in dogs. Materials and Methods: A total of 16 dogs in two different groups were used. Tooth movement of dog premolars resulted from approximately 200 g of force. Histomorphometric analysis of premolar roots was assessed after 4 and 12 weeks of tooth movement by comparing nonresorptive to resorptive surfaces. Results: Histomorphometric analysis indicated a significant decrease in the bone formation rate in the root resorptive areas, which resulted in decreased bone volume after 12 weeks. The threshold to detect RR in periapical radiographs was about 1.0 mm². Conclusions: A sustained mechanical load, due to the prolonged stress and strain of continuous mechanics, induces elevated bone metabolic activity, such as the bone turnover (remodeling) and change in bone volume (modeling). Therefore, our data support the hypothesis that increased RR is related to decreased bone formation (turnover) in high stress areas exposed to prolonged orthodontic tooth movement. [ABSTRACT FROM AUTHOR]

Bimaxillary protrusion in a 28-year-old woman was complicated by multiple missing, restoratively compromised, or hopeless teeth. The maxillary right central incisor had a history of avulsion and replantation that subsequently evolved into generalized external root resorption with Class III mobility and severe loss of the supporting periodontium. This complex malocclusion had a discrepancy index of 21, and 8 additional points were scored for the atrophic dental implant site (maxillary right central incisor). The comprehensive treatment plan included extraction of 4 teeth (both maxillary first premolars, the maxillary right central incisor, and the mandibular right first molar), orthodontic closure of all spaces except for the future implant site (maxillary right central incisor), augmentation of the alveolar defect with an autogenous chin-block graft, enhancement of the gingival biotype with a connective tissue graft, and an implant-supported prosthesis. Orthodontists must understand the limitations of bone grafts. Augmented alveolar defects are slow to completely turn over to living bone, so they are usually good sites for implants but respond poorly to orthodontic space closure. However, postsurgical orthodontic treatment is often indicated to optimally finish the esthetic zone before placing the final prosthesis. The latter was effectively performed for this patient, resulting in a total treatment time of about 36 months for comprehensive interdisciplinary care. An excellent functional and esthetic result was achieved. [ABSTRACT FROM AUTHOR]

This paper examined early developmental trajectories in a large, longitudinal sample at high-risk for ASD (‘HR’) and low-risk (‘LR’) controls, and the association of trajectories with 3-year diagnosis. Developmental assessments were conducted at 6, 12, 24 months, and 3 years, with blinded “clinical best-estimate” expert diagnosis at age 3. HR infants were enrolled based only on familial risk. LR infants, from community sources, had no first- or second-degree ASD relatives. All infants were born at 36–42 weeks, weighing ≥2500 g, with no identifiable neurological, genetic, or severe sensory/motor disorders. Analytic phase I: semi-parametric group-based modeling to identify distinct developmental trajectories ( n = 680; 487 HR; 193 LR); phase II: Trajectory membership in relation to 3-year diagnosis ( n = 424; 310 HR; 114 LR). Three distinct trajectories emerged (1) inclining; (2) stable-average; (3) declining; trajectory membership predicted diagnosis ( χ 2 = 99.40; p < .001). Most ASD cases were in stable-average (50.6%) or declining trajectories (33.8%); most non-ASD-HR infants were in inclining (51.9%) or stable-average (40.3%) trajectories. The majority of LR controls were in the inclining trajectory (78.9%). Within the declining trajectory, over half had ASD (57.8%), but 40% were non-ASD-HR infants. Declining/plateauing raw scores were associated with, but not exclusive to, ASD. Findings underscore the importance of monitoring the emergence of ASD symptoms and overall development in high-risk children. Evidence of developmental slowing or decline may be associated not only with ASD, but with other suboptimal outcomes, warranting careful clinical follow-up. [ABSTRACT FROM AUTHOR]

Objective: To assess the three-dimensional (3D) skeletal response to a standardized 5 mm of rapid maxillary expansion (RME) in growing children (6-15 years) with maxillary width deficiency and crowding. Materials and Methods: A bonded appliance was used prior to the eruption of the maxillary first premolars (Mx4s), and a banded appliance was used thereafter. A consecutive sample of 89 patients (29 boys and 60 girls) from a large pediatric dentistry and orthodontics practice was divided into four groups: 1)6-8 years old (n = 26), 2)9-11 years old with unerupted Mx4s (n = 21), 3) 9-11 years with erupted Mx4s (n = 23), and 4)12-15 years (n = 19). For all patients, the 3D evaluation of dental and skeletal effects was performed with cone-beam computed tomography (CBCT). Results: For both appliances in all patients, CBCT confirmed a triangular pattern of expansion in both the frontal and sagittal planes. Overall, both appliances produced significant maxillary expansion (>80% of the 5-mm activation), but older children showed a progressively more dental (less skeletal) response. Comparison of the two types of expanders in the crossover sample, children aged 9-11 years, showed that the bonded RME produced the most efficient skeletal expansion in the preadolescent sample. Increased maxillary width at the level of the zygomaticomaxillary suture was the best indicator for development of maxillary arch circumference. Conclusion: Development-dependent appliances (bonded APE before Mx4s erupt, and a banded device thereafter) provided optimal RME treatment for all children from age 6-15 years. [ABSTRACT FROM AUTHOR]

Abstract: The current study aims to describe the cognitive profile, autism profile, medical and behavioral presentation of children with a dual diagnosis of cerebral palsy (CP) and autism spectrum disorder (ASD). Little is known about the dual presentation of CP and ASD. Timely diagnosis is imperative as early intervention may impact a child''s developmental trajectory. The study used a cross-sectional descriptive design. We report data on cognitive profiles, ASD presenting symptoms, the time to definitive diagnosis of ASD, medical and behavioral co-morbidities in children with a dual diagnosis of CP and ASD. Seventy-two percent (72%) of children with CP+ASD had a developmental disability profile. Children were diagnosed with ASD at the median age of 66.5 months (range: 31–210 months). Repetitive behaviors were the most common ASD alerting symptom. Repetitive motor mannerisms were reported in 71% of CP+ASD population. Constipation, asthma and aggression showed highest statistical differences between CP+ASD group and CP only group. Our study has established that cognitive impairment is common amongst children with CP+ASD. ASD is diagnosed later in children with CP+ASD, than reference age of diagnosis in children with ASD. Medical and behavioral co-morbidities are common in children with CP+ASD. Clinicians need to be sensitized to the possibility of multiple diagnoses including ASD in children with cerebral palsy. [Copyright &y& Elsevier]

Objective: Utilize American Board of Orthodontics (ABO) cast/radiographic evaluation (CRE) to compare a series of 63 consecutive patients, finished with manual wire bending (conventional) treatment, vs a subsequent series of 69 consecutive patients, finished by the same orthodontist using the SureSmile2 (SS) method. Materials and Methods: Records of 132 nonextraction patients were scored by a calibrated examiner blinded to treatment mode. Age and discrepancy index (DI) between groups were compared by t-tests. A chi-square test was used to compare for differences in sex and whether the patient was treated using braces only (no orthopedic correction). Analysis of covariance tested for differences in CRE outcomes and treatment times, with sex and DI included as covariates. A logarithmic transformation of CRE outcomes and treatment times was used because their distributions were skewed. Significance was defined as P , .05. Results: Compared with conventional finishing, SS patients had significantly lower DI scores, less treatment time (,7 months), and better CRE scores for first-order alignment-rotation and interproximal space closure; however, second-order root angulation (RA) was inferior. Conclusion: SS patients were treated in less time to better CRE scores for first-order rotation (AR) and interproximal space closure (IC) but on the average, malocclusions were less complex and second order root alignment was inferior, compared with patients finished with manual wire bending. (Angle Orthod. 2011;81:383-388.) [ABSTRACT FROM AUTHOR]

Objective: To test the hypothesis that there is no relationship between the components of the American Board of Orthodontics (ABO) discrepancy index (DI) and duration of orthodontic treatment. Materials and Methods: A retrospective review of 732 patient records with permanent dentition was performed. Pretreatment radiographs and casts were used to determine the DI score. Other data collected were total treatment duration, age, sex, ethnicity, and the date fixed appliances were removed. Reliability tests showed substantial agreement between examiners (Cohen's kappa 0.68-0.94). Pearson and Spearman correlation coefficients were used to assess the association between the DI scores and length of treatment. A multiple variable regression analysis was used to determine which variables predict treatment duration (P < .05 significant). Results: There was a significant association between the DI and treatment duration. There was a significant multivariate association for DI components (occlusions, crowding, overjet, cephalometrics, overbite, lateral open bite, and tooth transposition) and treatment duration. Conclusions: The hypothesis was rejected. This retrospective study of university clinical records showed that the average increase in treatment duration was about 11 days for each point increase in total DI score. Treatment duration was differentially increased by various components of the DI: approximately 6.5 months for tooth transposition; approximately 1 month for crowding, overjet, or overbite; approximately 3 weeks for occlusion discrepancies; approximately 2 weeks for lateral open bite; and approximately 5 days for cephalometric discrepancies. [ABSTRACT FROM AUTHOR]

Introduction: Although much imaging research has focused on the localization and the management of impacted canines, optimal biomechanics for successful recovery are not clear. The purpose of this research was to compare the 3 mechanics—Kilroy spring, elastic chain, and steel ligature wire—used for the management of impacted canines by quantifying the 6 components of force systems involved with each system. Methods: A dentoform model was modified to simulate a palatally impacted canine. Load cells installed in the dentoform simultaneously measured the 3 forces (Fx, Fy, Fz) and the 3 moments (Tx, Ty, Tz) on the canine. The activation range and force system attenuation as the canine moved were also measured. The results were analyzed statistically. Results: The Kilroy spring has an activation range of 13 mm (Fz), the elastic chain has an activation range of 12 mm (Fz), and the ligature wire has an activation range of 1 mm (Fz). The full range of the elastic chain cannot be used because of its limited elastic behavior. Conclusions: The 3-dimensional force system for canine recovery mechanics can be quantified by using these devices. Quantification of the force system provides critical information for appropriate selection of an optimal appliance. [ABSTRACT FROM AUTHOR]

Introduction: The American Board of Orthodontics’ discrepancy index (DI) was designed to objectively quantify the complexity of a malocclusion before orthodontic treatment. In this study, we assessed the influence of age and sex on the DI distribution of a large mixed sample of patients. An additional objective was to ascertain the effectiveness of the DI for predicting the probability that 1 resident can complete the treatment of the malocclusion in a 24-month residency. Methods: A group of 6 calibrated investigators independently determined the DI scores for 716 consecutive patients in the permanent dentition from the patient pool of Indiana University’s graduate orthodontics program over 7 years. The DI was scored and compared with the patient’s sex and age, and it was noted whether the patient was transferred to a second resident when the first one graduated. Results: The DI is not significantly related to sex or age, but it was a significant predictor for patients who required transfer to a second resident for completion of treatment. Conclusions: The DI was a relatively stable index for measuring malocclusion complexity. It is independent of sex or age but is a consistent indicator of the greater time and effort required to complete treatment, because of the significant correlation to the necessity to transfer patient care to a second resident. [ABSTRACT FROM AUTHOR]

Introduction: The development of incipient caries, or white spot lesions (WSLs), is a significant clinical problem in orthodontics. The purpose of this study was to retrospectively determine the incidence and severity of WSLs by examining pretreatment and posttreatment digital photographs. Methods: A total of 332 consecutive finished patients from a university graduate orthodontic clinic were evaluated. Initial and final digital images were compared to assess WSLs. The facial surfaces of the anterior 8 maxillary teeth were analyzed. The percentage area of WSL per total facial tooth surface was calculated to control for magnification differences. Reliability of the method was assessed by comparison with direct clinical examination data. Patient and operator factors, and treatment complexity and outcomes were evaluated as predictors of WSL incidence and severity. Results: Agreement between direct clinical examination and digital photo data was excellent, with an intraclass correlation coefficient 0.88 and a 0.3% average difference between methods. The incidence of at least 1 WSL on the labial surface of the anterior 8 maxillary teeth was 36%. The order of incidence was lateral incisor (34%), canine (31%), premolar (28%), and central incisor (17%). Conclusions: Risk factors for the development of incipient caries during orthodontic treatment were young age (preadolescent) at the start of treatment, number of poor hygiene citations during treatment, unfavorable clinical outcome score, white ethnic group, and inadequate oral hygiene at the initial pretreatment examination. The use of computer software to evaluate digital photos retrospectively is a valid method for assessing the incidence and severity of WSLs on the maxillary anterior incisors, canines, and premolars. [ABSTRACT FROM AUTHOR]

Objective: To determine the relationship of the ABO Discrepancy Index (DI) to outcomes for routine malocclusions, and to ascertain whether significant trends in DI scores could be noted among annual samples of patients taken from 1998 to 2004. Materials and Methods: A total of 716 consecutive patients with permanent dentition from a large urban graduate orthodontics program were sampled over the 7-year span. A group of six researchers with a dental background were trained and calibrated in the various components of the DI method to ensure reproducible criteria and accurate recording of clinical and radiographic data across researchers. Data management and analyses were undertaken by two other investigators who were not involved in data coding. Results: Only a weak positive association was seen between the DI and Objective Grading System (OGS) and Comprehensive Clinical Assessment (CCA) scores. The DI was not significantly related to a general time trend. Conclusion: The DI was found to be a reliable and relatively stable index for measuring malocclusion complexity in annual samples of patients. Although the DI is significantly related to outcomes for the most severe malocclusions, it was not a good predictor of outcome for more routine malocclusions. If the minimal acceptable outcome is defined as 30 OGS points, the mean DI (15.7) and the average OGS score (28.2) indicate that many of the malocclusions in patients in the present sample were of potential board quality. [ABSTRACT FROM AUTHOR]

Introduction: Tooth movement simulation is important for planning the optimal force system and appliance design to correct a specific malocclusion. Experimental verification of a 3-dimensional force system is described for a unique molar root movement strategy that can be adapted to many clinical scenarios. Methods: The force system was measured for molar root movement springs that had adjustable alpha (anterior) and beta (posterior) moments. A 3-dimensional transducer assessed moments and forces in 3 planes during deactivation and simulated molar rotation. Two experimental situations were compared by using 10 springs in each group: spring reactivation was performed to compensate for changes in the force system caused by molar movement, or there was no reactivation. Results: Without reactivation, the force system becomes unfavorable after approximately 5° of molar movement (rotation). With reactivations, a favorable force system through 20° of molar movement is maintained. Conclusions: Present root-movement appliances require periodic adjustment to achieve optimal tooth movement. Additional studies are needed to design orthodontic appliances for delivering optimal force systems for the entire range of tooth movement. [Copyright &y& Elsevier]

The article examines the effectiveness of the dental equipment Memory-Maker in changing the shape of superelastic nickel titanium wires. Studies found that the Memory-Maker has been very effective in changing the shape of superelastic nickel titanium wires without destructing their superelastic properties. The Memory-Maker has also been used by orthodontists and oral surgeons on several clinical applications, especially in cases that are not easily addressed with commercial archwires.

Introduction: External apical root resorption (EARR) is an unwanted sequelae of orthodontic treatment. Genetic factors account for approximately 64% of the EARR variation in humans. Inbred mice offer a model to control the environmental factors and genetic heterogeneity that complicate human genetic studies. Genetically distinct inbred mice and their offspring (F1s) were analyzed to examine the mode of inheritance and the influence of parental sex on the susceptibility to root resorption associated with orthodontic force (RRAOF). Methods: RRAOF was determined histologically for male and female mice of the A/J, DBA/2J, and BALB/cJ strains, and the A/J × DBA/2J and A/J × BALB/cJ crosses (10 males and 10 females/reciprocal cross). RRAOF was induced by tipping the maxillary first molar mesially for 9 days. Results: Sex differences were observed only among the mice of the BALB/cJ strain. Two patterns of inheritance were observed; F1s from the A/J × BALB/cJ cross were resistant, suggesting that the A/J have dominant resistance alleles. On the other hand, F1s from the A/J × DBA/2J cross showed RRAOF intermediate between their parental mice, suggesting a polygenic trait. Conclusions: These results provide evidence of a traceable and polygenetic component affecting RRAOF in mice. [Copyright &y& Elsevier]

Objective: To determine if an increase in tooth contacts is the principal effect of tooth positioner wear. Materials and Methods: Patient charts from a consecutive series were reviewed until a sample of 100 cases that used a tooth positioner was obtained. One hundred control cases were randomly selected from patients treated at the same period. Malocclusion severity and finished occlusion were assessed with the American Board of Orthodontics (ABO) Discrepancy Index (DI) and Objective Grading System (OGS) score, respectively. Finish casts for each patient were mounted on a Galleti articulator. Occlusal registrations were obtained with silicone-based impression material from casts fabricated from impressions taken at the time of fixed appliance removal (control) or at the end of the tooth positioner treatment (experimental). The number of the perforations and transparent areas on the occlusal registrations were quantified. Results: There was no significant difference (P = .20) in the number of total occlusal contacts between the two groups. However, the OGS score of the tooth positioner group (16.7) was significantly (P = .0009) better than for the control group (19.9). Conclusions: Tooth positioners were effective in improving the occlusal finish, but the effects were independent of an increase in occlusal contacts. Positioners primarily improved first order alignment by tipping teeth into an improved intercuspation. [ABSTRACT FROM AUTHOR]