State-dependent memory produced by aerobic exercise

A survey was administered to 168 parents and their children at the end of mixed dentition treatment for Class II correction utilizing bionators and headgears to investigate attitudes of parents and patients toward bionators and headgears and to elicit factors associated with compliance. Directional differences between parent and child responses occurred frequently with agreement ranging from 41 to 100%, averaging 69% overall. The results indicate that the orthodontic patient population has medical and dental health as a priority. While parental and child reasons for seeking treatment may be different, it appears that both groups seek care for perceived benefits of health, decreased present and future oral problems, peer influences, and dental self image improvement. Additionally, children who are undergoing treatment perceive that others do not understand what they are going through, they may be embarrassed, and some may break their appliances to annoy the parent or orthodontist. Pain, decreased ability to speak, and difficulty chewing were reported to decrease appliance wear. Patient understanding of the treatment goals was reported to increase compliance. The bionator caused more instances of speech problems and associated non-compliance than the headgear. The headgear caused more instances of pain, but did not cause significantly less associated compliance than the bionator. The results suggest that bolstering the patient-orthodontist relationship, informing the patient about the treatment goals, methods, and their individual role, and offering immediate short term rewards can potentially increase patient compliance.     

Control of the vertical dimension in Class II correction using a cervical headgear and lower utility arch in growing patients. Part I

A retrospective cephalometric study was performed comparing three groups of 30 growing patients with Class II, Division 1 malocclusions. Group 1 was treated with a cervical headgear/lower utility arch combination (CHG/LUA), group 2 was treated with a cervical headgear alone (CHG), and the third group was untreated. The average treatment time was 1 year, 6 months. No other appliances were used during this period. Maxillary and mandibular dental and skeletal treatment responses were compared with an analysis of variance (ANOVA) and a Scheffe's test. In addition, a multiple stepwise regression was performed to determine whether pretreatment measures of facial pattern were accurate predictors of mandibular rotational response. Both treatment groups demonstrated significant reduction in maxillary protrusion. The CHG-only group showed significantly greater anterior descent of the palatal plane as compared with the untreated group. The maxillary molars showed significant distal movement in both treatment groups without any extrusion beyond that seen with normal growth. The maxillary incisor demonstrated significant retroclination in the CHG-only group. There was no statistical difference among the groups for variables commonly used for measuring mandibular rotation or protrusion. The change in vertical position of the lower molar was not significantly different among the groups. A CHG as used in this study produced maxillary orthopedic and orthodontic changes without upper molar extrusion beyond that seen with normal eruption and in the absence of an opening rotation of the mandible, even in subjects with dolicocephalic facial patterns. The LUA did not appear to influence lower molar eruption or mandibular rotational response. None of the commonly used predictors of facial pattern, such as the Y-axis, XY-axis, or MP angle, accurately predicted mandibular rotational response. Further study would be necessary to ascertain whether this was a result of their invalidation as predictors, or a result of the treatment strategy employed.     

Treatment response to maxillary expansion and protraction

A prospective clinical trial was conducted to determine the skeletal and dental contributions to the correction of overjet and overbite in Class III patients. Thirty patients (12 males and 18 females with a mean age of 8.4 +/- 1.7 years) were treated consecutively with protraction headgear and fixed maxillary expansion appliances. For each patient, a lateral cephalogram was taken 6 months before treatment (T0); immediately before treatment (T1); and 6 months after treatment (T2). The time period (T1-T0) represented changes due to 6 months of growth without treatment; (T2-T1) represented 6 months of growth and treatment. Each patient served as his/her own control. Cephalometric analysis described by Bj?rk (1947) and Pancherz (1982a,b) was used. Sagittal and vertical measurements were made along the occlusal plane (OLs) and the occlusal plane perpendicular (OLp), and superimposed on the mid-sagittal cranial structure. The results revealed the following: with 6 months of treatment, all subjects were treated to Class I or overcorrected to Class I or Class II dental arch relationships. Overjet and sagittal molar relationships improved by an average of 6.2 and 4.5 mm, respectively. This was a result of 1.8 mm of forward maxillary growth, a 2.5-mm of backward movement of the mandible, a 1.7-mm of labial movement of maxillary incisors, a 0.2-mm of lingual movement of mandibular incisors, and a 0.2-mm of greater mesial movement of maxillary than mandibular molars. The mean overbite reduction was 2.6 mm. Maxillary and mandibular molars were erupted occlusally by 0.9 and 1.4 mm, respectively. The mandibular plane angle was increased by 1.5 degrees and the lower facial height by 2.9 mm. Individual variations in response to maxillary protraction was large for most of the parameters tested. Significant differences in treatment changes between male and female subjects were found only in the vertical eruption of mandibular incisors and maxillary and mandibular molars. These results demonstrate that significant overjet and overbite corrections can be obtained with 6 months of maxillary protraction in combination with a fixed expansion appliance.     

Shape-coordinate analysis of skeletal changes induced by rapid maxillary expansion and facial mask therapy

The aim of this study was to evaluate maxillary and mandibular shape/size changes by means of Bookstein's shape-coordinate and tensor analysis in children with Class III malocclusions treated with rapid maxillary expansion and a facial mask in order to define optimum timing of intervention for this type of therapy. The treated group (46 subjects, 26 females and 20 males) was divided into two subgroups according to the stage of dentitional development. The early-treated group consisted of 23 subjects treated in the early mixed dentition (mean age at Time 1, 6 years 9 months +/- 7 months); the late-treated group included 23 subjects treated in the late mixed dentition (mean age at Time 1, 10 years 3 months +/- 1 year). The mean treatment period was about 11 months. The control group (32 subjects with untreated Class III malocclusion, 18 females and 14 males) also was divided into two subgroups (an early control group, 17 subjects in the early mixed dentition, and a late control group, 15 subjects in the late mixed dentition). Maxillary triangles (point T, the most superior point of the anterior wall of sella turcica, point FMN, the fronto-maxillary-nasal suture, and point A) and mandibular triangles (point Condylion, point Gonion, and point Pogonion) were digitized on cephalograms in both groups at Time 1 and Time 2. Combined facial mask and rapid maxillary expansion therapy produced a significant enhancement of the forward growth of the maxilla and significantly more upward and forward direction of growth of the mandibular condyle (leading to smaller increments in mandibular total length, Co-Pg) in the early-treated group when compared with controls and to the late-treated group. Both maxillary size and mandibular size were significantly affected by treatment in the early mixed dentition. The results of this study indicate that orthopedic treatment of Class III malocclusion induces favorable size and shape changes both in the maxilla and mandible, and that this combined treatment approach is more effective in the early mixed dentition than in the late mixed dentition.     

The effects, limitations, and long-term dentofacial adaptations to treatment with the Herbst appliance

The purpose of this article is to summarize the existing scientific data with respect to the short- and long-term effects of the Herbst appliance on the occlusion and on the maxillo/mandibular complex. The article also discusses the treatment indications and possible treatment limitations. The Herbst method is most effective in the treatment of Class II malocclusions. Long-term stability seems to be dependent on a stable cuspal interdigitation. Marked mandibular morphological changes occur during therapy and sagittal condylar growth is increased. Posttreatment, most of the mandibular morphological changes revert and no long-term influence of Herbst treatment on mandibular growth can be verified. The appliance effect on the maxillary complex can be compared with that of a high-pull headgear. Without proper retention, however, this effect is of a temporary nature. Herbst treatment is especially indicated in the permanent dentition at or just after the pubertal peak of growth. Mixed dentition treatment is not recommended, as a stable cuspal interdigitation after therapy is difficult to achieve and relapses are prone to occur. In the nongrowing patient, the appliance should be used with great caution.     

Guiding occlusal development with functional appliances

Functional appliances have been used in orthodontics since their introduction by Pierre Robin almost one hundred years ago, however, our understanding of how they bring about orthodontic correction is still limited. This article is a brief overview of their history, mode of action, advantages and disadvantages, and includes the results of a study of attempts to control and minimise their side-effects using a recent development in functional appliances: the 'Teuscher Appliance'. This appliance combines a high-pull headgear with the activator, and is designed to reduce the often reported side-effects of functional appliances. The skeletal and dentoalveolar effects of treatment with the Teuscher Appliance on 40 consecutively-treated patients are reported and illustrated with four individual case reports. The results showed that the skeletal effect on the maxilla was a retardation of the normal forward and downward growth in 80 per cent of the cases, and that mandibular growth in 70 per cent of cases was forward. In patients whose mandibular growth was primarily in a vertical direction, such growth could be ascribed mainly to posterior rotation of the maxilla and/or the fact that the acrylic covering the lower posterior teeth to correct a deep bite was removed, promoting the eruption of these teeth and increasing the anterior vertical development. The dentoalveolar changes were characterised by retroclination of the maxillary incisors in 90 per cent of the patients, and were due to insufficient torque control by the built-in torque springs, which need further development. The mandibular incisors were well controlled by capping. The statistical analysis showed an inverse correlation between the initial incisor inclination and the change during treatment. This suggests that proclination of the lower incisors, as previously reported, is not a contra-indication to functional appliance treatment, provided the appliance is correctly designed. Overall, this study showed considerable individual response to treatment, and that the occlusal correction occurred through a combination of skeletal and dentoalveolar changes.     

Antihistamine-containing cough/cold medications present a low hazard in pediatric accidental exposure incidents: analysis of Poison Control Center data

Although the mandibular condyle is one of the most common sites of injury of the facial skeleton, it is also the most overlooked and least diagnosed site of trauma in the head and neck region. The condyle forms the very cornerstone of mandibular form and function and therefore injuries to the mandibular condyle in growing children may adversely affect growth and development of the jaws and the occlusion. The aim of this article is to present an overview of condylar injuries in growing patients for the purpose of increasing the awareness of all dental practitioners involved in the treatment of children with acute oro-facial injuries.     

A growth control approach to Class II, Division 1 cases during puberty involving the simultaneous application of maxillary growth restriction and mandibular forward induction

A simple method that used headgear and a functional appliance simultaneously was used for the correction of Class II, Division 1 cases with severe denture base discrepancy. The treatment restricted the forward growth of the maxilla and advanced the mandible. The functional appliance, referred to as the mandibular growth advancer (MGA), advances the mandible progressively with a splint, with the objective of remodeling the condyle and the glenoid fossa in the temporomandibular joint. Functional adaptation was achieved as the muscles that are attached to the mandible adjusted to new positions. In the two cases that illustrate this method, the ANB angle decreased and the Ar-B distance increased over a short period to four and six times the mean Japanese growth rate, respectively. After the correction of the denture-base discrepancy, a multibracket fixed appliance was used for dental alignment, and good skeletal, occlusal relationships and profiles were obtained. Treatment of severe denture-base discrepancy in this manner may reduce the skeletal abnormality, decrease the number of extraction cases, and shorten the subsequent multibracket treatment time. And it may reduce the iatrogenic side effects caused by prolonged mechanotherapy with a fixed appliance.     

Use of activator appliances in pediatric patients treated with costochondral grafts for temporomandibular joint ankylosis: analysis of 13 cases

PURPOSE: The long-term outcomes and clinical results of costochondral transplants used for the treatment of condylar ankylosis of the mandible in children with and without application of postoperative activator appliances are evaluated and compared. MATERIALS AND METHODS: A nonrandomized, retrospective clinical study of 13 cases of condylar ankylosis (16 joints) of the mandible surgically treated during a 9-year period from 1988 to 1997 was performed. All 13 patients were treated by condylectomy and immediate costochondral rib grafts. Nine of these patients underwent long-term postoperative therapy using removable activator appliances. Four patients did not undergo activator therapy postoperatively. Casts, radiographs, photographs, computed tomography (CT) scans, magnetic resonance imaging (MRI) and 99Tc bone scans were used postsurgically to evaluate graft take, condylar growth and function, occlusion, and facial and condylar symmetry. RESULTS:The postoperative and long-term clinical results in both groups showed costochondral growth center transplants to be effective in restoring mandibular growth of the affected side. However, symmetry, arch coordination, correction of occlusal canting, mandibular deviation, facial growth, and prevention of reankylosis were obtained and better controlled only in those cases that underwent long-term orthodontic activator therapy postoperatively and were followed closely. CONCLUSIONS: Children with long-standing condylar ankylosis of the mandible and its resultant facial asymmetry and occlusal canting (secondary to a nonfunctional joint and maxillary compensation) treated with condylectomy and immediate costochondral rib graft reconstruction of the affected joint were treated more favorably when activators were used postsurgically. The patients that failed to comply with or continue activator therapy postsurgically developed complications relating to mandibular deviation, occlusal dysharmony, asymmetry and, in one case, reankylosis of the temporomandibular joint (TMJ).     

Treatment of Class II, Division 2 in the late growth period

The "Deckbiss" with skeletal Class II jaw relationship sometimes presents a considerable therapeutic problem, particularly in the late growth period (DP3U), as regards the coordination of dental and skeletal treatment objectives. An effective treatment approach was demonstrated: a modified Herbst appliance used simultaneously with fixed appliances in the maxilla. The sample comprised 12 male (14.0 +/- 0.9 years old) and 10 female (12.3 +/- 0.4 years old) patients. Correction of the distal occlusion was achieved in all patients by means of the Herbst appliance, which was removed after an average time period of 6.4 +/- 0.2 months. In the mandible the multibracket appliances were then immediately inserted, and Class II elastics were used for retention. Maximum anchorage was required in the maxilla as well as in the mandible. Complete diagnostic records were made at the beginning of the treatment as well as 6 and 12 months later, in order to document skeletal and dental changes. A dental and skeletal Class I relationship was achieved in all cases. A significant improvement was recorded in the vertical jaw base relationship; this was still stable after a period of 12 months. In the dental area in particular, a so-called high-pull headgear effect (intrusion and distalization 16, 26) and intrusion of teeth 34, 44 were registered. Only a minor protrusion of the mandibular incisors was observed. Reinforcement of the bands reduced the failure rate significantly. The Herbst appliance does not represent a standard treatment for Class II. Its indication range is limited.     

Skeletal effects of early treatment of Class III malocclusion with maxillary expansion and face-mask therapy

The effectiveness of maxillary expansion and face-mask therapy in children with Class III malocclusion was studied in a sample of 46 subjects in mixed dentition and compared with a control sample of 32 subjects with untreated Class III malocclusion. Treated and untreated samples were divided into early and late mixed-dentition groups to aid identification of the optimum timing of the orthopedic treatment of the underlying skeletal disharmony. Cephalometric analysis was based on a stable basicranial reference system, appropriate for longitudinal studies started in the early developmental ages. The level of significance for intergroup comparisons was set at a p value of 0.01. Significant forward displacement of the maxillary complex was found in the early-treatment group. The region of the pterygomaxillary suture, in particular, showed significant changes in the subjects treated during early mixed dentition. No significant maxillary modifications were recorded in the late-treatment group. Both early and late groups exhibited smaller increments in mandibular protrusion and larger increments in the intermaxillary vertical relationship compared with their respective Class III control groups. Only children treated at an early age, however, showed a significant upward and forward direction of condylar growth, leading to smaller increments in total mandibular length. These results indicate that the combination of a bonded maxillary expander and face-mask therapy is more effective in early mixed dentition than in late mixed dentition, especially with regard to the magnitude of the protraction effects on maxillary structures.     

A holographic study of variations in bone deformations resulting from different headgear forces in a macerated human skull

The effects of headgear on maxillary displacement and the resulting growth modifications are not completely understood, especially regarding the complex relationships between initial and secondary skeletal reactions on one hand and the influence of the direction and magnitude of the applied force on the other. The aim of the present investigation was to study, by means of holographic interferometry, the initial bone displacement occurring in response to headgear traction applied at different force magnitudes and in different directions. Orthopedic forces of 560 grams and orthodontic forces of 354 grams were stimulated on a macerated human skull. The forces came from from high-, straight-, and low-pull headgear traction directed above, through, and below the center of resistance of the maxillary first permanent molars. Immediate skeletal changes were recorded by laser holography. Initial displacements of the maxilla and zygomatic arch in both horizontal and vertical planes were evaluated on frontal and lateral holograms. In most cases, both force magnitudes caused substantial displacements in both planes, albeit to different extents. Complex bending, and rotational, translational, and relative displacements were observed. The direction of displacement did not strictly coincide with that of the applied force. The results of this study indicate that both orthodontic and orthopedic headgear traction may lead to complex initial three-dimensional skeletal displacement in directions not always corresponding with the direction of the applied force.     

Midazolam-fentanyl-isoflurane anaesthesia is suitable for haemodynamic and fluid balance studies in pigs

The effects of various directed forces applied by combined headgear were evaluated in this study. The study material consisted of 30 patients with Class II dental relationships and steep mandibular plane angles. Three groups of 10 patients each were formed. In the first treatment group, forces of 150 gm per side were used for the high-pull component and the cervical component. In the second treatment group, forces of 200 gm per side for the high-pull component and 100 gm per side for the cervical component were applied. In the third treatment group, forces of 100 gm per side were applied for the high-pull component and 200 gm per side for the cervical component. Distal tipping of upper molar was greatest in the third treatment group. Intrusion of the upper molar in the second treatment group and extrusion of the upper molar in the third treatment group were statistically significant. Changes in occlusal and mandibular plane angles showed significant differences between the groups.     

Arteriovenous malformation of the mandible. Apropos of a case in a 6-year-old child

Arteriovenous malformations of the mandible are uncommon. Though characteristic clinical and radiological presentations are well described, management in the case of children is still a matter of debate. We report a mandibular angioma in a 6-year-old girl which was treated with superselective embolization. This method is the treatment of choice for mandibular arteriovenous malformations in children because of the low complication rate and the preservation of healthy tissue. When the malformation continues to develop despite repeated embolizations, surgical treatment may be necessary.     

Craniofacial and dental characteristics of Silver-Russell syndrome

We found significant differences in a craniometric, cephalometric, and dental study of 19 Silver-Russell syndrome patients (13 without growth hormone treatment) with appropriate controls. Although head circumference was normal for age, head length was increased, while cranial and facial widths and facial heights were reduced. Posterior facial height, posterior cranial base length, cranial base height, and mandibular body size were significantly smaller than in healthy children of the same height. Articulatory speech disorders were common. Enamel defects pointed to an early prenatal insult. Delayed dental age and small mandibular and cranial base dimensions support the possibility of physiological growth hormone deficiency in many Silver-Russell syndrome children; however, facial soft tissue structures were strikingly different from those observed in classical growth hormone deficiency.     

Craniofacial adaptations induced by chincup therapy in Class III patients

The purpose of the present study is to examine the effects of an orthopedic force produced by chincup treatment in patients with Class III malocclusion. Anteroposterior maxillary and mandibular changes were examined as were changes in the vertical dimension. Further, the possibility of posterior displacement of temporomandibular joints in treated Class III subjects was evaluated. Serial lateral headfilms of 22 young females (average age, 9 years), who had received chincup therapy were compared with those of 20 skeletal Class III subjects of similar age who received no treatment during the interval studied. A computerized x-y coordinate program was applied to analyze the cephalometric landmarks and measurements. The treated group showed improvement of the skeletal Class III pattern associated with a slight increase (0.8 degrees per year) in SNA and a slight decrease (-0.7 degrees per year) in SNB and also a decreased gonial angle. The distance from the condyle to the chin (Co-Gn or effective mandibular length) increased significantly less in the treated group in comparison with controls. Increases in lower anterior facial height were not different between the treated and untreated groups. In addition, the cranial base angles N-S-Ba and N-S-Ar showed no statistical difference between groups, but these angles tended to increase with time in both groups. Basion and Articulare showed almost the same amount of backward and downward movement in both groups. The results of this study indicate that the primary effect of chincup therapy was in producing a reduction in mandibular growth increments during the period studied. Maxillary growth was not affected during treatment. Further, the results of this study fail to support the hypothesis that chincup appliance significantly induces the posterior displacement of the glenoid fossa.     

The structural organization of the nucleus thoracicus in the feline spinal cord after destruction of the amygdaloid body in the brain

A total of 280 children and adolescents with congenital and acquired mandibular defects and deformations were treated. The main principle in the treatment of such children is to begin treatment as early as possible. Stages of rehabilitation and scope of therapeutic measures for each stage are determined. The best results were attained in patients administered multiple-modality treatment by surgical, orthodontic, physiotherapeutic methods and therapeutic exercises at an early age immediately after the defect was diagnosed.     

Midfacial growth after costochondral graft construction of the mandibular ramus in hemifacial microsomia

PURPOSE: The purpose of this study was to document vertical midfacial growth after costochondral graft mandibular ramus construction in children with type IIB and type III hemifacial microsomia (HFM). METHODS: This is a retrospective study of 33 children who underwent costochondral graft (CCG) construction for mandibular type IIB (abnormal, small, and medially displaced ramus, n = 19) and mandibular type III (absent ramus and glenoid fossa, n = 14) HFM, between 1980 and 1990. Types I and IIA patients were not included because their milder mandibular deformities were lengthened by osteotomy. Mean age at operation was 6.2 (2 to 10) years, and the mean follow-up period was 5.5 (1 to 13.5) years. Occlusal cant, piriform angle, and intergonial angle were measured on the most current posteroanterior (PA) cephalogram. The ratio of unaffected to affected ramus length was determined on the most current panoramic radiograph. Patient outcomes were classified based on the occlusal cant at the latest follow-up: group 1, successful result with a symmetrical maxilla (occlusal cant of <5 degrees); group 2, acceptable result (occlusal cant > or =5 degrees but <8 degrees), and Group 3, failure (occlusal cant > or = 8 degrees). OMENS scores were calculated for each patient: each of the five major anatomic deformities of HFM (orbital, mandibular, auricular, neural, and soft tissue) were graded 0 to 3 and summed. The mean differences in age at operation and OMENS scores between groups were calculated (ANOVA). RESULTS: At the end of follow-up, patients defined as having a successful result (group 1) had a mean occlusal cant of 2 degrees, a mandibular length ratio of 1.0, and an intergonial angle of 2 degrees. However, the final piriform angle was 7 degrees, indicating less vertical midfacial growth than maxillary alveolar growth. These patients were older at the time of operation (mean age, 6.7 years), and their mean OMENS score (6.3) was significantly lower (P = .004) than in patients in group 2 (mean age at operation, 6.3 years; mean OMENS score, 6.8) and group 3 (mean age at operation, 5.8 years; mean OMENS score, 7.8). In group 2, the occlusal cant, mandibular length ratio, and intergonial and piriform angles did not improve. In group 3, the occlusal cant and piriform angle became worse during the follow-up period. CONCLUSIONS: The results of this study indicate that after construction of the ramus and condyle in type IIB and III HFM patients, vertical midface growth is secondary to a combination of midfacial and alveolar growth. Patients operated on at an older age were more likely to have a successful long-term result. Finally, the severity of the overall deformity, as reflected in a higher OMENS score, appeared to be an important factor in the response to early correction.     

High-resolution physical map of the X-linked retinoschisis interval in Xp22

Treatment of a skeletodental Class II vertical growth problem, combined with a severe arch length deficiency in both arches, presents a challenging orthodontic problem. This is the case report of a small-statured, 11-year, 10-month-old boy with a history of juvenile chronic arthritis and marked mandibular retrognathia who was treated with first premolar extractions in both arches. Unexpected favorable growth, with significant decrease of the mandibular plane angle over a long treatment period, provided a very satisfactory result. [This case report was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process.]     

Intermaxillary forces during activator treatment

The mode of action of the activator appliance is still unclear. Apart from a possible mandibular growth enhancing effect, some investigators believe that orthopedic forces may be applied to the maxilla, contributing to Class II correction by inhibition of maxillary growth. In addition, orthodontic forces may arise that produce dentoalveolar changes. The purpose of this study was to measure the magnitude of anteroposterior intermaxillary forces during wear of the activator appliance. Ten consecutive patients with Class II dental and skeletal relationships were treated with a modified activator appliance. The appliance had maxillary and mandibular segments that could be detached from each other during the measuring session. A force transducer was placed at the anterior part of the maxillary segment, and the anteroposterior force exerted by the mandibular segment was measured. Measurements were taken in the upright and reclined position at every patient visit for a period of 6 months. Results indicated that intermaxillary forces were generally in the orthodontic range (median values of 100 gf at the upright position and 123 gf at the reclined position). A wide variation in force levels was noted, both between patients and for the same patient during the experimental period. No statistically significant change in force levels was observed during the 6 month period and no difference was noted between upright and reclined posture.