Alternate Expansions Research Articles

Does Maxillary Protraction with Alt-RAMEC Protocol Affect Inferior Sclera Exposure? A Controlled 3dMD Study.

The purpose of this controlled retrospective study was to measure and evaluate the inferior sclera exposure changes using 3dMD stereophotogrammetric images in a prepubertal Class III patient sample that underwent maxillary protraction with alternate rapid maxillary expansions and constrictions protocol followed by facemask. The study group included 15 prepubertal patients (mean age: 9.85 ± 1.44 years) with Class III malocclusion due to maxillary retrognathism. Nine weeks of alternate rapid maxillary expansions and constrictions protocol was followed prior to 7 months of face mask treatment and 3 months of retention with Bionator. Pretreatment (T0) and post-retention (T1) lateral cephalometric radiographs and 3dMD images were retrieved from clinical archive. The same records were used for a control group of 15 well-matched, untreated patients (mean age: 9.4 ± 0.79 years). The distance between the upper eyelid margin and the lower eyelid margin was recorded as the overall eye height (E), and the distance between inferior limbus and the lower eyelid margin was recorded as inferior sclera exposure (S). The S : E ratio in percentage was calculated. Sella-nasion-A point angle (SNA) was used as the skeletal variable. SNA angle, right S : E, and left S : E changed significantly in both groups at T1-T0. The intergroup comparison was highly significant for SNA angle but was not significant for right and left S : E variables. The S : E ratio decreased significantly in both alternate rapid maxillary expansions and constrictions/facemask and the control groups. However, the change in S : E ratio between groups was not significant.

Comparison of the short-term effects of facemask therapy preceded by conventional rapid maxillary expansion or by an alternate rapid maxillary expansions and constrictions protocol : Aretrospective study.

We aimed to compare the short-term effects of alternate rapid maxillary expansion and constriction (Alt-RAMEC) with conventional rapid maxillary expansion (RME) followed by facemask (FM) therapy. A total of 30patients who had received facemask therapy after RME or Alt-RAMEC protocols were included in the study. The Alt-RAMEC/FM and RME/FM groups were created to be well-matched regarding cervical vertebral maturation stage and sex. In the Alt-RAMEC group (10males and 5females, 10.99 ± 1.80years), expansion screws were activated for aweek (two turns/day), then deactivated in the following week (two turns/day). The activation-deactivation protocol continued for 6 or 7weeks. In the RME/FM group (10males and 5females, 11.61 ± 1.20years), screw activation was performed according to the patients' requirements. Lateral cephalograms which had been taken at the beginning of treatment and at the end of the facemask therapy were analyzed. Intragroup and intergroup differences were statistically analyzed. Both groups showed asignificant sagittal advancement of the maxilla. However, the Alt-RAMEC/FM group showed statistically greater improvements than the RME/FM group for SNA (3.11 ± 1.79 vs. 1.45 ± 1.34, p = 0.008), ANB (4.29 ± 1.80 vs. 2.95 ± 1.19, p = 0.023), convexity (8.91 ± 4.29 vs. 5.61 ± 2.51, p = 0.016), and overjet (5.86 ± 2.29 vs. 4.61 ± 2.10, p < 0.001). The sagittal mandibular, vertical skeletal, dental, and soft tissue changes were similar between the groups (p > 0.05). The Alt-RAMEC protocol was found to be more effective in the correction of skeletal classIII malocclusion in the short term.

Dynamical behavior of alternate base expansions

AbstractWe generalize the greedy and lazy $\beta $ -transformations for a real base $\beta $ to the setting of alternate bases ${\boldsymbol {\beta }}=(\beta _0,\ldots ,\beta _{p-1})$ , which were recently introduced by the first and second authors as a particular case of Cantor bases. As in the real base case, these new transformations, denoted $T_{{\boldsymbol {\beta }}}$ and $L_{{\boldsymbol {\beta }}}$ respectively, can be iterated in order to generate the digits of the greedy and lazy ${\boldsymbol {\beta }}$ -expansions of real numbers. The aim of this paper is to describe the measure-theoretical dynamical behaviors of $T_{{\boldsymbol {\beta }}}$ and $L_{{\boldsymbol {\beta }}}$ . We first prove the existence of a unique absolutely continuous (with respect to an extended Lebesgue measure, called the p-Lebesgue measure) $T_{{\boldsymbol {\beta }}}$ -invariant measure. We then show that this unique measure is in fact equivalent to the p-Lebesgue measure and that the corresponding dynamical system is ergodic and has entropy $({1}/{p})\log (\beta _{p-1}\cdots \beta _0)$ . We give an explicit expression of the density function of this invariant measure and compute the frequencies of letters in the greedy ${\boldsymbol {\beta }}$ -expansions. The dynamical properties of $L_{{\boldsymbol {\beta }}}$ are obtained by showing that the lazy dynamical system is isomorphic to the greedy one. We also provide an isomorphism with a suitable extension of the $\beta $ -shift. Finally, we show that the ${\boldsymbol {\beta }}$ -expansions can be seen as $(\beta _{p-1}\cdots \beta _0)$ -representations over general digit sets and we compare both frameworks.

Species delimitation and evolutionary relationships among Phoebis New World sulphur butterflies (Lepidoptera, Pieridae, Coliadinae)

ABSTRACTThe most accepted taxonomic treatment of the New World sulphurs of the genus Phoebis Hübner, [1819] recognizes 16 species including those in the current synonyms Aphrissa and Rhabdodryas. This total conflicts with the results of several recent pierid DNA barcode studies across the Neotropics. We used a five‐locus dataset to carry out species delimitation analyses using the coalescence‐based method implemented in bpp software. After testing the resulting species hypotheses using marginal likelihood estimates, we inferred their phylogenetic relationships and performed an ancestral range reconstruction with biogeobears. Our analyses recovered two different hypotheses, 26 and 24 species, that scored the highest marginal likelihood estimate. Differences between these two hypotheses, when reconciled with barcode clusters and morphology, indicated that 24 is the most likely number of species. Phoebis neocypris stat. rev., Phoebis rurina stat. rev., Phoebis virgo stat. rev., Phoebis marcellina stat. rev., Phoebis thalestris stat. rev., and Phoebis rorata stat. rev. are raised to the species rank. We dated the crown age of Phoebis to the mid‐Miocene, with the islands of the Greater Antilles as the most probable ancestral range. Three main clades of Phoebis diverged early in the evolutionary history of the genus, but most extant species‐level diversity arose after the Pliocene–Pleistocene boundary. Our analyses recovered alternate range expansions and contractions, and dispersal from the islands to the continent and back, in the three main clades. Both sympatric and allopatric speciation seem to have shaped the current species richness.

Comparative Study of Maxillary Expansion by Alternate Rapid Maxillary Expansion and Constriction Versus Hyrax Expansion

Aim of study: was to evaluate the skeletal and dental effects of maxillary expansion by alternate rapid maxillary expansions and constrictions technique in comparison to conventional RME expansion by Hyrax by using PA cephalometry. Material and methods: Twenty patients with constricted maxillary arch represented with an unilateral or bilateral posterior cross bite were selected with ages ranged from 12-15 years. Patients were divided randomly into two equal groups by computer aided randomization according to the protocol of expansion into (Group I): who received alternate rapid maxillary expansions and constrictions (Alt-RAMEC) protocol and (Group II): who received conventional RME protocol. Results: Skeletally, the Latero-Nasal Width and the Maxillary width recorded higher mean values in Alt-RAMEC group than RME group with statistical significance. Dentally, all linear and angular measurements recorded higher mean values postoperatively in Alt-RAMEC group than RME group with no statistical significance except upper inter-incisal width mesial. Conclusions: Alt-RAMEC protocol produces highly skeletal effects by increasing the nasal width and the maxillary width.

Dentofacial Effects of Modified Alt-RAMEC Protocol Combined with the Facial Mask for Treatment of Preadolescent Caucasian Class III Patients

ABSTRACTIntroductionIn this study we analyzed dentoskeletal effects of orthopedic therapy with rapid palatal expander (RME), used according to modified Alt-RAMEC protocol, followed by facial mask in preadolescent patients with class III malocclusion.Materials and methodsThe sample consisted of 10 patients treated consecutively with the alternate rapid maxillary expansions and constrictions (Alt-RAMEC) protocol and facial mask before the pubertal growth spur the patients were re-evaluated after about one year of treatment. We compared the cephalometric analyses at T0 (before the treatment) and T1 (just after the end of the treatment—about 1 year), evaluating 18 parameters. The normality of each distribution was assessed with D’Agostino-Pearson normality test and significative differences between T0 and T1 were assessed with paired t test (p < 0.05).ResultsSagittal measurements of the maxilla (SNpSNa distance) showed significant improvements (p < 0.0001) with protraction effect at point A. Significant improvements were recorded also at Wits appraisal and overjet. Measures of the mandibular growth (Co-Gn) showed increased values at T1, as well as vertical dimension (SNpSNa-GoGn). No significant variations were recorded at the dental parameters.ConclusionThis protocol induces important skeletal effects, like advancement of the maxilla, also in preadolescent patients, while dental changes are minimal. Alt-RAMEC protocol seem to modulate maxillary development in patients near the pubertal growth spurt.How to cite this articleRota E, Ferrari M, et al. Dentofacial Effects of Modified Alt-RAMEC Protocol Combined with the Facial Mask for Treatment of Preadolescent Caucasian Class III Patients. Int J Clin Pediatr Dent 2019;12(3):222–228.

The immediate effect of alternate rapid maxillary expansions and constrictions on the alveolus: a retrospective cone beam computed tomography study

BackgroundRapid maxillary expansion reduced the expander’s anchor teeth buccal alveolar bone thickness. However, the effects of alternate rapid maxillary expansions and constrictions (Alt-RAMEC) on the expander’s anchor teeth alveolar thickness has not been assessed. The purpose of this retrospective study was to evaluate the effects of Alt-RAMEC on the alveolus surrounding the anchor teeth of a double-hinged expander.MethodsTwenty-six individuals, including 12 males (11.5 ± 1.00 years) and 14 females (11.5 ± 0.90 years), who had double-hinged expander for 7 weeks of Alt-RAMEC and then 3 months of maxillary protraction, were included. Their cone beam computed tomography (CBCT) images taken 3–6 months before treatment (T0) and after 7 week of Alt-RAMEC (T1), were studied for the buccal alveolar bone thickness (BABT) and palatal alveolar bone thickness (PABT) of the expander’s anchor teeth (first molars and first and second premolars) in four axial sections. The intra-class correlation coefficient, Dahlberg’s formula, and paired t tests were used to analyze the method errors, and the intra-group changes of the BABT and PABT at T0-T1 were analyzed by paired t test (p < 0.05).ResultsThe 7 weeks of Alt-RAMEC significantly reduced the BABT of the expander’s anterior anchor teeth (0.54~ 70 mm, p < 0.05) and at the cervical region (0.14~ 0.25 mm, p < 0.05), but not at the apical region of the expander’s posterior anchor teeth. The reduction of BABT by 7 weeks of Alt-RAMEC was within the scope of the initial BABT. On the opposite, the Alt-RAMEC significantly (p < 0.05) increased the PABT in the anterior anchor teeth and the cervical region of posterior anchor teeth.ConclusionsA 7-week protocol of Alt-RAMEC with double-hinged expander for maxillary protraction might reduce the buccal alveolar bone thickness of the expander’s anchor teeth, although the reduction is within the scope of initial alveolar thickness of the expander’s anchor teeth.

Cone-beam computed tomography evaluation of bone plate and root length after maxillary expansion using tooth-borne and tooth-tissue-borne banded expanders.

The objective of this research was to evaluate the buccal bone plate and root length of maxillary permanent first molars using cone-beam computed tomography after maxillary expansion with different activation protocols. Cone-beam computed tomography images of growing patients were obtained from the orthodontic department of Pontifical Catholic University of Rio Grande do Sul in Brazil. The groups were Haas-type 2/4 turns, Haas-type 4/4 turns, hyrax-type 2/4 turns, and hyrax-type with alternate rapid maxillary expansions and constrictions (alt-RAMEC) 4/4 turns a day. Tooth length, periodontal insertion, alveolar bone thickness, and intermolar distances were evaluated. The data at the start oftreatment and 6months later were compared using generalized linear models. The intergroup differences were determined by univariate analysis of variance with the Bonferroni adjustment. Tooth length was significantly shortened after expansion in all groups (-0.28 to -0.51mm), except for the alt-RAMEC group. Bone level variables (bone level and bone level at the tooth tip) changed statistically in all groups, except for the Haas 4/4 turns group. There was significant periodontal attachment loss after rapid maxillary expansion with the hyrax/alt-RAMEC (5.09mm). The hyrax/alt-RAMEC andhyrax groups had more dehiscences, fenestrations, and exposures of the root. The consequence of rapid maxillary expansion using the hyrax was alveolar bone resorption, especially in the hyrax/alt-RAMEC group, whereas the Haas expander caused mild root resorption.

Atomic Level 1D Structural Modulations at the Negatively Charged Domain Walls in BiFeO3 Films

Charged domain walls (CDWs) show great potentials to mediate the properties of ferroelectrics. Direct mapping of these domain walls at an atomic scale is of critical importance for understanding the domain wall dominated properties. Here, based on aberration‐corrected scanning transmission electron microscopy, tail‐to‐tail CDWs at 71°, 109°, and 180° domains in BiFeO3 thin films have been identified. 2D mappings demonstrate 1D structural modulations with alternate lattice expansions and clockwise/counterclockwise lattice rotations at these CDWs. Such behaviors of CDWs reveal a remarkable contrast to the uncharged domain walls and imply delicate interactions between bound charges and structural compensations of domain wall. These results are expected to provide new information on domain wall structures and shed some light on the understanding of domain wall properties in ferroelectrics.

Early treatment of Class III malocclusion by RME and modified Tandem appliance

Patients with a skeletal Class III malocclusion and maxillary deficiency can be treated successfully using a combined protraction facemask and alternate rapid maxillary expansions and contractions (Alt-RAMEC). However, due to poor patient compliance during facemask therapy there has been growing interest in intraoral appliances for correcting Class III malocclusion. The tandem traction bow appliance (TTBA) is an intraoral appliance which has been used successfully for the treatment of growing Class III patients. This case report describes the management of a 10-year-old boy with a Class III malocclusion and maxillary deficiency treated with modified TTBA appliance.

Comparative characterization of maxillary expansion and alternate maxillary expansions and constrictions in rats.

The purpose of this study was to evaluate whether the cranial and circumaxillary sutures react differently to maxillary expansion (ME) and alternate maxillary expansions and constrictions (Alt-MEC) in a rat model. Twenty-two male Sprague-Dawley rats (6 weeks old) were used and divided into three groups. In ME group (n=9), an expander was activated for 5 days. In Alt-MEC group (9 animals), an alternate expansion and constriction protocol (5-day expansion and 5-day constriction for one cycle) was conducted for 2.5 cycles (25 days total). The control group comprised 4 animals with no appliances used, each of two sacrificed on day 5 and day 25 respectively. Midpalatal suture expansion or constriction levels were assessed qualitatively and quantitatively by bite-wing X-rays and cast models. Distances between two central incisors and two maxillary first molars were measured on cast models after each activation. Circumaxillary sutures (midpalatal, maxillopalatine, premaxillary, zygomaticotemporal and frontonasal suture) in each group were characterized histologically. Results showed that midpalatal suture was widened and restored after each expansion and constriction. At the end of activation, the widths between both central incisors and first molars in Alt-MEC group were significantly larger than those in ME group (P<0.05). Histologically, all five circumaxillary sutures studied were widened in multiple zones in Alt-MEC group. However, only midpalatal suture was expanded with cellular fibrous tissue filling in ME group. Significant osteoclast hyperplasia was observed in all circumaxillary sutures after alternate expansions and constrictions, but osteoclast count increase was only observed in midpalatal suture in ME group. These results suggested that cranial and circumaxillary sutures were actively reconstructed after Alt-MEC, while only midpalatal suture had active reaction after ME.

Skeletal, soft tissue, and airway changes following the alternate maxillary expansions and constrictions protocol

To evaluate the skeletal, soft tissue, and airway effects of the alternate maxillary expansions and constrictions (Alt-RAMEC) protocol in prepubertal patients. The appliance containing a double-hinged expansion screw was applied to 20 patients with Class III skeletal malocclusion characterized by maxillary retrognathia. The mean age of the study group was 9 years and 8 months. The patients' parents were instructed to open the screw by 1 mm per day during the first week and to close it by 1 mm per day the week after. This alternate opening and closing was repeated for 9 consecutive weeks. Cone beam computed tomography records and three-dimensional photographs were taken before treatment and after 9 week of the Alt-RAMEC protocol. Point A moved slightly forward (0.89 mm) and downward (0.92 mm) (P < .05). The average amount of expansion achieved at the level of point A was 5.54 mm (P < .05). Besides the maxilla, the expansive forces also affected the nasal bone, the zygomaticomaxillary and zygomaticotemporal sutures (P < .05). The soft tissue nasal width increased significantly. The airway volume of the anterior nasal compartment and the nasal cavity also increased (P < .05). Slight forward movement of point A occurred with the Alt-RAMEC protocol. The expansion affected not only the maxilla but also other structures of the face. Significant cutaneous changes occurred in the paranasal area. Some significant increase in the upper airway volume was obtained.

Effects of facemask treatment anchored with miniplates after alternate rapid maxillary expansions and constrictions; A pilot study

To describe the dentoskeletal and soft tissue effects of facemask treatment anchored with miniplates after alternate rapid maxillary expansions and constrictions (Alt-RAMEC) in maxillary retrusion patients. The sample consisted of 15 patients with a mean skeletal age of 11.6 ± 1.59 years undergoing 8 weeks of Alt-RAMEC followed by maxillary protraction. Three hundred fifty to 400 g of force per side was applied to the facemask from the titanium miniplates inserted on the lateral nasal wall of the maxilla. Total treatment time was 9.9 ± 2.63 months. Treatment changes were evaluated cephalometrically and analyzed by means of the dependent t-test and the Wilcoxon signed rank test. The miniplates withstood the orthopedic forces exerted during the treatment. Cephalometric findings showed that the maxilla moved forward by 2 mm, with an 0.8° counterclockwise rotation and without maxillary incisor movement. The mandible moved slightly in a downward and backward direction (1.2°). The inclinations of the mandibular incisors decreased significantly (2°). Statistically significant increases were observed in the vertical dimension (1°-1.3°). Soft tissue changes were more marked in the upper lip and soft tissue pogonion than in the lower lip. This treatment approach can offer an advantage for correcting mild/moderate maxillary retrusion in Class III patients.

Dentoskeletal Effects of Maxillary Protraction in Cleft Patients with Repetitive Weekly Protocol of Alternate Rapid Maxillary Expansions and Constrictions

To evaluate the amount of maxillary protraction with face mask in complete unilateral cleft lip and palate patients submitted to two distinct rapid maxillary expansion (RME) protocols. The sample consisted of 20 individuals (nine boys and 11 girls; mean age of 10.4 +/- 2.62 years) with unilateral complete cleft lip and palate who had a constricted maxilla in the vertical and transverse dimensions. Ten patients underwent 1 week of RME with screw activation of one complete turn per day, followed by 23 weeks of maxillary protraction (group 1). The other 10 patients underwent 7 weeks of alternate rapid maxillary expansion and constriction, with one complete turn per day, followed by 17 weeks of maxillary protraction (group 2); both groups underwent a total of 6 months of treatment. Cephalometric measurements were taken at different times: pretreatment (T1), soon after RME (T2), and after 6 months of treatment (T3). Each measurement was analyzed with mixed models for repeated measures, and the covariance structure chosen was compound symmetry. The maxilla displaced slightly forward and downward with a counterclockwise rotation; the mandible rotated downward and backward, resulting in an increase in anterior facial height; the sagittal maxillomandibular relationship was improved; the maxillary molars and incisors were protruded and extruded; and the mandibular incisors were retroclined. There was no significant difference between the groups in evaluation time.

Opening of Circumaxillary Sutures by Alternate Rapid Maxillary Expansions and Constrictions

To analyze quantitatively the circumaxillary suture opening after alternate rapid maxillary expansions and constrictions (Alt-RAMEC). Twelve inbred cats were randomly grouped into two equal groups for 1 week of rapid maxillary expansion (RME) (1 mm/day) or 5 weeks of Alt-RAMEC (1 mm/day). At the end of the experiment, the craniofacial skeleton of each cat was harvested. Each circumaxillary suture was then probed at three sites with a 0.5-mm pointed periodontal probe. A smooth probing without penetration was an ineffective suture opening (<0.5 mm), while a probing with penetration was an effective suture opening (>0.5 mm). For each suture, the quantity of suture opening (%) was the effective suture opening/(effective + ineffective suture opening). The intergroup differences were analyzed by chi-square test (P < .05). Five weeks of Alt-RAMEC opened the circumaxillary sutures significantly more than 1 week of RME. This affected the circumaxillary sutures running coronally and articulating directly to the maxilla (56.9% vs 36.1%, P < .001), the sutures running sagittally, but articulating indirectly to the maxilla (94.4% vs 64.8%, P < .001), and the sutures running coronally, but articulating indirectly to the maxilla (58.3% vs 33.3%, P < .01). The sutures running sagittally were opened significantly more (94.4%-100.0%) than those running coronally (56.9%-58.3%), no matter if they articulated directly or indirectly with the maxilla. Alt-RAMEC opens both the sagittally and coronally running circumaxillary sutures quantitatively more than conventional RME. However, more than 5 weeks of Alt-RAMEC would be needed to increase the opening of the coronally running circumaxillary sutures. (

A expansão rápida da maxila com haas e a fala na fissura labiopalatina transforame

OBJETIVO: verificar os efeitos da Expansão Rápida da Maxila (ERM), com aparelho Haas, na fala do paciente com fissura labiopalatina (FLP) Transforame. MÉTODOS: 12 indivíduos entre sete e 14 anos, sendo seis meninos e seis meninas, divididos em dois grupos. O Grupo 1 (G1), submetido à ERM com protocolo de ativação convencional e, o Grupo 2 (G2), submetido à ERM com protocolo de ativação preconizado por Liou e Tsai (2005) com expansões e constrições alternadas. Realizou-se avaliação da fala, análise acústica com programa Praat e avaliação perceptivo-auditiva por julgadores fonoaudiólogos e leigos. RESULTADOS: a medição dos tempos de emissão das vogais por análise acústica mostrou diferença estatisticamente significante na avaliação pós-ERM da vogal /i/ no G1 e da vogal /a/ no G2. Na avaliação perceptivo-auditiva, não houve diferenças estatisticamente significantes entre os grupos nas avaliações de Nasalidade e Clareza na Articulação, porém, na medida em que os julgadores atribuíram melhora à Nasalidade, também atribuíram melhora à Articulação e, assim também em relação as variáveis "Melhor", "Igual" e "Pior". CONCLUSÃO: a diminuição dos tempos de emissão pós-ERM, indica que o aumento no escape aéreo nasal ocasiona menores tempos de emissão. A análise perceptivo-auditiva mostrou-se um instrumento eficaz de avaliação, havendo concordância entre julgadores leigos e fonoaudiólogos. Essa avaliação indicou também, que na medida em que a nasalidade diminui ocorre maior clareza na articulação.

A New Protocol for Maxillary Protraction in Cleft Patients: Repetitive Weekly Protocol of Alternate Rapid Maxillary Expansions and Constrictions

It was hypothesized that, through a repetitive weekly protocol of Alternate Rapid Maxillary Expansions and Constrictions (Alt-RAMEC), the maxilla in cleft patients could be protracted more effectively than with a single course of rapid maxillary expansion (RME). Twenty-six consecutive unilateral cleft lip and palate patients at the age of mixed dentition were included in this prospective clinical study. The rapid maxillary expansion group included the first 16 consecutive patients undergoing 1 week of rapid maxillary expansion (1 mm/day) followed by 5 months, 3 weeks of maxillary protraction. The Alternate Rapid Maxillary Expansions and Constrictions group included the next 10 consecutive patients undergoing 9 weeks of Alternate Rapid Maxillary Expansions and Constrictions followed by 3 months, 3 weeks of maxillary protraction. Daily activation of the weekly expansion or constriction was 1.0 mm. Two-hinged expanders and intraoral maxillary protraction springs were used in both groups. Treatment results were evaluated cephalometrically. The amount of maxillary anterior displacement by the 2-hinged expander in the Alternate Rapid Maxillary Expansions and Constrictions group was 3.0 +/- 0.9 mm at A point, significantly greater than the 1.6 +/- 1.0 mm in the rapid maxillary expansion group. The amount of maxillary advancement with intraoral protraction springs in the Alternate Rapid Maxillary Expansions and Constrictions group was 2.9 +/- 1.9 mm at A point, significantly greater than the 0.9 +/- 1.1 mm in the rapid maxillary expansion group. The overall amount of maxillary advancement in the Alternate Rapid Maxillary Expansions and Constrictions group was 5.8 +/- 2.3 mm at A point. This result remained stable, without significant relapse after 2 years. Maxillary protraction using the 2-hinged expander, a repetitive weekly protocol of Alternate Rapid Maxillary Expansions and Constrictions, and intraoral protraction springs is most effective, with stable results at 2-year follow-up.

AO, COWL, and Observed Climate Trends

Abstract The linear trends for a number of fields obtained from the reanalyses of the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) are calculated for the Northern Hemisphere winter months (January–March) from the 55-yr period of 1948–2002. The fields include sea level pressure (SLP); geopotential height at 500 and 50 hPa; temperature at 500 and 50 hPa; zonally averaged height; temperature; zonal, meridional, and vertical velocities from 1000 to 50 hPa; and surface air temperature (SAT). The trend fields are expressed in terms of two alternate expansions: (i) contributions from the Arctic Oscillation (AO) and cold ocean–warm land (COWL) patterns, as defined from the leading modes of an empirical orthogonal function (EOF) analysis of sea level pressure; or (ii) contributions from the modified AO (AO*) and modified COWL (COWL*) patterns, defined from the leading EOFs of 500-hPa height. The residuals in each expansion are considered, and the completeness p...

New orthodontic and orthopaedic managements on the premaxillary deformities in patients with bilateral cleft before alveolar bone grafting

At the age of mixed dentition, a downward or laterally displaced premaxilla with a wide alveolar cleft in patients with bilateral cleft lip and palate remains a dilemma both for orthodontists and surgeons. These premaxillary deformities not only make the alveolar bone grafting difficult but also aesthetically and functionally unacceptable. The purpose of the present article is to introduce three new orthodontic and orthopaedic techniques for solving these premaxillary deformities and facilitating alveolar bone graft through a non‐surgical approach. These techniques are the premaxillary orthopaedic intrusion for correcting a downward displaced premaxilla, the premaxillary orthopaedic repositioning for correcting a laterally displaced premaxilla, and maxillary orthopaedic protraction by alternate rapid maxillary expansions and constrictions for minimizing a wide alveolar cleft. They were evaluated clinically and cephalometrically for their treatment effects. The results revealed that the premaxillary and cleft deformities were corrected in a short period of time and therefore the alveolar bone grafting could be carried out without difficulty in all of the patients who received the treatment. The treatment effects were mostly orthopaedic and partly orthodontic. No growth disturbance on the maxilla was observed throughout the treatment. These new orthodontic and orthopaedic techniques are very effective for solving the difficult‐to‐treat premaxillary deformities and facilitating the alveolar bone grafting in the patients with bilateral cleft.

Ancestor controlled submodule inclusion in design databases

A paradigm is proposed for representing hierarchically specified design data in CAD database systems in which there are alternate expansions of hierarchically specified modules. The paradigm uses an ancestor-based scheme to control which instances of submodules are to be placed in the expansion of each instance of a given module and is formalized using a versioned directed acyclic multigraph (VDAG). The approach is aimed at reducing storage space in engineering design database systems and at providing a means for designers to specify alternate expansions of a module. The VDAG model is defined, and a mechanism by which a VDAG generates an exploded forest of design trees is described. Algorithms are provided to generate a design forest from a given VDAG, determine whether one module is contained by a larger module, extract a version from a VDAG, test whether two VDAGs are equivalent, and try to reduce the size of a VDAG. The problems of module containment and VDAG inequivalence are shown to be NP-complete, and the problem of finding a minimum sized VDAG equivalent to a given VDAG is shown to be NP-hard. >