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Anti-protozoal efficacy of high performance liquid chromatography fractions of Torilis japonica and Sophora flavescens extracts on Neospora caninum and Toxoplasma gondii.

We previously reported that alcoholic extracts of Sophora flavescens and Torilis japonica from South Korea demonstrated good efficacy in reducing replication of Toxoplasma gondii and Neospora caninum. To characterize the chemical component associated with anti-protozoal activity, specific fractions were isolated by high performance liquid chromatography (HPLC) and used for in vitro testing. These fractions were evaluated in vitro against T. gondii and N. caninum. Fractions of the herb extracts were serially diluted to final concentrations of 2.850 to 0.356 ng/ml in medium and added to wells containing replicating T. gondii and N. caninum. To determine the ability of each fraction to inhibit parasite proliferation, 3H-uracil incorporation was used to determine parasite replication. In cultures infected with T. gondii, a fraction of T. japonica (TJ2) inhibited T. gondii proliferation by 99.2, 94.4, 88.6 and 27.0% in the range from 2.850 to 0.356 ng/ml. Four fractions of S. flavescens (SF1-SF4) inhibited T. gondii proliferation by 99.6-60.6, 96.9-48.1, 92.3-68.2 and 95.4-52.9% in the range from 2.850 to 0.356 ng/ml. In cultures infected with N. caninum, a fraction of T. japonica (TJ2) inhibited N. caninum proliferation by 98.3, 95.5, 79.7 and 30.6% in the range from 2.850 to 0.356 ng/ml. Four fractions of S. flavescens (SF1-SF4) inhibited N. caninum proliferation by 97.1-25.9, 94.8-35.5, 95.9-33.7 and 95.4-49.4% in the range from 2.850 to 0.356 ng/ml. These fractions of T. japonica and S. flavescens extracts are currently undergoing in vivo evaluation in experimentally infected mice.

Animals↗

Extraction treatment using a palatal implant for anchorage.

AIM: To describe the use of Straumann Orthosystem implants for orthodontic anchorage. METHODS: The Straumann Orthosystem consists of a titanium palatal implant and connected device, which can be used when absolute anchorage is required. In the present study the implant was placed in the midline at the junction of the alveolar process and hard palate. The implant was osseointegrated 13 weeks after placement. A palatal arch attached to the implant and upper first molar bands was used to provide stationary anchorage in a 23 year-old female with protruding upper anterior teeth and moderate crowding of both arches. CONCLUSION: A palatal implant provides stationary anchorage for retraction of anterior maxillary teeth.

Adult↗

Dens evaginatus from an orthodontic perspective: report of several clinical cases and review of the literature.

The anomaly of dens evaginatus manifests itself as an innocuous-looking tubercle of enamel on the occlusal surface of a premolar tooth. Problems can arise when the tubercle is either worn, ground, or fractured off, resulting in pulpal exposure and possible loss of vitality of the tooth. Orthodontists should be particularly aware of this dental anomaly, which occurs in at least 2% of the Asian and Native Indian population. Premolar extraction cases should be planned to include extraction of the anomalous premolars instead of the normal ones. In addition, the orthodontist should be wary of occlusal changes during treatment or occlusal equilibration that might jeopardize the vitality of teeth with dens evaginatus. Pulp-capping or partial pulpotomy has been postulated as the most reliable form of treatment to prevent loss of vitality of the affected teeth and to allow continued root maturation where necessary.

Adolescent↗

Clinical management in extraction cases using palatal implant for anchorage.

This case report presents a Class I extraction treatment in an adult patient with bimaxillary crowding using a palatal implant for anchorage control. The implant (pure titanium 6 mm SLA) is inserted in the middle of the palate, after a careful radiological assessment on a lateral cephalogram. At the end of the healing period (13 weeks), an anchorage device, such as a squared trans-palatal bar connecting the maxillary molars to the palatal implant, is projected and placed in order to obtain the posterior anchorage control. The orthodontic treatment was performed according to the bidimensional technique.

Adult↗

Mandibular second premolar extraction--postretention evaluation of stability and relapse.

The dental casts and cephalometric radiographs of 46 patients, treated with mandibular second premolar extraction and edgewise orthodontic mechanotherapy, were evaluated for changes over a minimum 10-year postretention period. The sample was divided into two groups: early (mixed dentition) extraction of mandibular second premolars and late (permanent dentition) extraction of mandibular second premolars. Results showed no difference in long-term stability between the two groups. Arch length and arch width decreased with time and incisor irregularity increased throughout the postretention period. No predictors or associations could be found to help the clinician in determining the long-term prognosis in terms of stability. The sample was regrouped according to the postretention degree of incisor irregularity. Statistically significant differences in cephalometric measurements were found between the minimally crowded group and the moderately to severely crowded group.

Adolescent↗

Nonextraction orthodontic therapy: posttreatment dental and skeletal stability.

To assess the long-term stability of nonextraction orthodontic treatment, the dental cast and cephalometric records of 28 cases were evaluated. Thirty cephalometric and seven cast parameters were examined before treatment, posttreatment, and an average of almost 8 years postretention. Results showed overall long-term stability to be relatively good. Relapse patterns seen were similar in nature, but intermediate in extent, between untreated normals and four first premolar extraction cases. Significant decreases were seen in arch length and intercanine width during the postretention period despite minimal changes during treatment. Incisor irregularly increased slightly postretention; intermolar width, overjet, and overbite displayed considerable long-term stability. Mandibular incisor mesiodistal and faciolingual dimensions were not associated with either pretreatment or posttreatment incisor crowding. Class II malocclusions with large ANB values and shorter mandibular lengths showed increased incisor irregularity, shorter arch lengths, and deeper overbites at the postretention stage, suggesting that the amount and direction of facial growth may have been partially responsible for maturational changes seen during the postretention period.

Adolescent↗

The time-factor in orthodontics: what influences the duration of treatments in National Health Service practices?

UNLABELLED: This study aimed to elucidate factors associated with duration of orthodontic treatment. METHODS: Retrospective analysis of a systematic 2% sample of cases completed in National Health Service practices in England and Wales. Records were collected during 1991. Characteristics of practitioners, patients, malocclusions, treatment variables and outcomes were evaluated. Data were submitted to multivariate analysis, with Log10 Time in Treatment as the dependent variable. RESULTS: Data were available for 1506 cases. The (geometric) mean time in treatment was 13 months. A model was found that explained 41% of the variance. Factors found to increase duration were fixed appliances, multiple stages in the treatments, premolar extractions, and correction of antero-posterior buccal occlusion. Age, buccal segment malocclusion, DHC (Dental Health Component of the Index of Orthodontic Treatment Need) grade 5 and orthodontically qualified practitioners were also associated with slightly longer treatments. CONCLUSIONS: Whilst briefer treatments may be attractive to purchasers, providers and recipients, it should be remembered that thorough treatment, and treatment of more complex malocclusions, tends to take longer. Economic pressures on practitioners to produce high turnovers of cases may be counterproductive in the quest for better outcomes.

Adolescent↗

Eruption and function of maxillary third molars after extraction of second molars.

After extraction of maxillary second molars, will the third molars erupt into a functional position in a timely manner? To answer this question, 56 consecutively treated cases of maxillary second molar extraction were reviewed. The unerupted positions of the maxillary third molars were measured on cephalometric radiographs, ages of eruption were evaluated, positions of erupted third molars analyzed, and interproximal periodontal health of adjacent first molars compared. The results showed that, generally, the eruption of third molars was accelerated. Most of the third molars had acceptable interarch and intra-arch occlusal relationships. The interproximal periodontal health of the third molars was similar to that of adjacent first molars. Most maxillary third molars will successfully erupt into an acceptable position by the late teens.

Adolescent↗

Stability of the palatal rugae as landmarks for analysis of dental casts in extraction and nonextraction cases.

To determine whether the positions of the palatal rugae were affected by orthodontic therapy, pre- and posttreatment maxillary dental casts of 57 adult patients treated in the graduate orthodontic clinic at the University of North Carolina were evaluated. The orthodontic extraction group (n = 27) was composed of patients whose treatment included the extraction of two maxillary premolars. The remaining patients (n = 30) had been treated without extractions. Transverse changes observed over time were significantly different from zero only for the medial points of the first rugae in the nonextraction group and for the lateral points of the first rugae in the extraction group. None of the changes observed in the transverse measures were statistically different between the two groups. In the extraction group, there were significant anteroposterior changes in the right lateral points between the first and second rugae and between the second and third rugae, and in the right medial points between the second and third rugae. There were no statistically significant anteroposterior changes observed in the nonextraction group over time. When the two groups were compared, the average distance between the lateral first and second right rugae, and the average distance between the lateral second and third right rugae were significantly different. The medial and lateral points of the third rugae appear to be stable landmarks for the construction of anatomic reference pints in longitudinal cast analysis.

Adolescent↗

Stability of the lower labial segment following orthodontic treatment--a comparison of treatment with Andresen and Begg appliances.

This retrospective cephalometric study of Class II division 1 malocclusions investigates the effects on the lower labial segment of two forms of orthodontic treatment. Non-extraction Andresen myofunctional therapy and first premolar extraction Begg treatment are compared to the lower incisor changes found in appropriate non-extraction and first premolar extraction control groups, which also presented with Class II division 1 malocclusions. Using four angular and two linear measurements, the lower labial segment was found to procline during Andresen therapy (1-2 degrees, 1-2 mm), and on withdrawal of the appliance it retroclined by about one-half of the in-treatment proclination (0.4-0.8 degrees, 0.1-0.5 mm). During extraction Begg mechanics, the lower incisors were found to retrocline (1.3-1.5 degrees, 0.4-0.9 mm), and they continued to retrocline following removal of the appliance (0.2-3.0 degrees, 0.8-1.1 mm). In general, the variables used to measure lower incisor position demonstrated only very small changes, and were near method error. The reliability of these changes are discussed. It is considered that the axial inclination of the lower incisor in relation to the mandibular plane is the most consistent and therefore still the most useful clinical measurement of lower incisor change available from cephalometric radiographs.

Activator Appliances↗

Lip curve changes in females with premolar extraction or nonextraction treatment.

Changes in lip curvature resulting from treatment have been largely ignored in orthodontic literature. The focus instead has been primarily directed at retraction of the vermilion border and changes in the nasolabial angle. This study, therefore, was designed to retrospectively analyze changes in the upper and lower lip curves associated with growth and treatment. The lateral cephalometric records of 137 female orthodontic patients were digitized. Sixty-two were treated with premolar extractions and 75 without extractions. The overall extraction group was further divided into subgroups on the basis of the chosen extraction sequence, which included extraction of 4/4, 4/5, or 5/5. Statistical analysis revealed no significant differences in changes in lip curve depth between the two overall samples, relative to either of the two reference lines. This would suggest that an appropriately selected plan, whether extraction or nonextraction, should allow treatment to be carried out without negative effects on the curvature of the lips. Calculation of correlation coefficients and regression analysis suggested that the inherent properties and morphology of the soft tissues themselves are probably the greatest determinants of lip curve behavior with treatment. The midface soft tissues appear to be less dependent on changes in the underlying hard tissues than do the lower face soft tissues. Pretreatment upper and lower incisor positions and angulations and the underlying vertical facial dimension appear to play more significant roles in the behavior of the lower lip than the upper lip.

Adolescent↗

[Tweed-Merrifield technique and vertical dimension in hyperdivergent Class II].

The cases presented in this paper share a common skeletal characteristic, hyperdivergence, a common therapeutic strategy, similar diagnostic elements, and a common choice of non-symmetrical extractions. Interceptive treatment is especially useful for this type of malocclusion to prevent deep over-bites, atypical habits, and severe malocclusion. In the Tweed-Merrifeld technique, orthodontists use careful dental, occlusal, cephalometric, and esthetic evaluations to establish an appropriate treatment plan and therapeutic strategy whose goal will be: to eliminate unhealthy compensations, re-position, if necessary, alveolar structures on basal bone, reduce anterior-posterior and vertical discrepancies, favor anterior mandibular rotation, improve facial esthetics, restore functional occlusion, and assure stability of results. Because of its consistent capability of achieving predictable resolution of the most varied and complex orthodontic disorders, the author has chosen this technique for routine use in his daily orthodontic practice.

Cephalometry↗

Predictors of relapse in orthodontically-treated Class III malocclusions.

This study aimed to investigate the possibility of predicting relapse from the pretreatment records of children with orthodontically treatable Class III malocclusions. Sixty-four patients were studied: 31 individuals had been treated by a non-extraction technique, the remaining 33 with mid-arch extractions. Cephalometric and model data taken at the start of treatment and at least 2 years after all treatment and retention had ceased were examined. An individual diagnosis of relapse or stability was made from the post-retention records and the start of treatment records analysed in relation to this information. The capacity for predicting the observed outcome of therapy was assessed in three ways: correlation coefficients, the number of cephalometric measurements exceeding two standard deviations from a control group mean, and discriminant analysis. Only the latter proved an effective indicator of relapse, with a separate discriminant model being necessary for each sub-group.

Adolescent↗

Maxillary and mandibular width changes studied using metallic implants.

The purpose of this implant study was to evaluate the transverse stability of the basal maxillary and mandibular structures. The sample included 25 subjects between 12 and 18 years of age who were followed for approximately 2.6 years. Metallic implants were placed bilaterally into the maxillary and mandibular corpora before treatment. Once implant stability had been confirmed, treatment (4 first premolar extractions followed by fixed appliance therapy) was initiated. Changes in the transverse maxillary and mandibular implants were evaluated cephalometrically and two groups (GROW+ and GROW++; selection based on growth changes in facial height and mandibular length) were compared. The GROW++ group showed significant width increases of the posterior maxillary implants (P <.001) and the mandibular implants (P =.009); there was no significant change for the anterior maxillary implants. The GROW+ group showed no significant width changes between the maxillary and mandibular implants. We conclude that (1) there are significant width increases during late adolescence of the basal mandibular and maxillary skeletal structures and (2) the width changes are related with growth potential.

Adolescent↗

Stability and relapse of mandibular anterior alignment: University of Washington studies.

For more than 40 years, research in the Department of Orthodontics, University of Washington (Seattle, WA) has focused on a growing collection of more than 800 sets of patient records to assess stability and relapse of orthodontic treatment. All patients had completed treatment a decade or more before the last set of data. Evaluation of treated premolar extraction patients, treated lower incisor extraction patients, treated non-extraction cases with generalized spacing, patients treated with arch enlargement strategies, and untreated normals showed similar physiologic changes: (1) Arch length decreases after orthodontic treatment. (2) Arch width measured across the mandibular canine teeth typically reduces posttreatment, whether or not the case was expanded during treatment. (3) Mandibular anterior crowding during the posttreatment phase is a continuing phenomenon well into the 20-to-40 years age bracket and likely beyond. (4) Third molar absence or presence, impacted or fully erupted, seems to have little effect on the occurrence or degree of relapse. (5) The degree of post-retention anterior crowding is both unpredictable and variable and no pretreatment variables either from clinical findings, casts, or cephalometric radiographs before or after treatment seem to be useful predictors.

Adult↗

Axiographic findings in patients undergoing orthodontic treatment with and without premolar extractions.

Mechanical axiography was performed on 49 (37 female, 12 male) patients prior to orthodontic treatment, after removal of the fixed appliance, and at the end of retention. Twenty-five subjects (mean age 12.8 years) underwent orthodontic treatment without premolar extractions (group 1) and 24 subjects (mean age 13.5 years) with premolar extractions (group 2). The axiographic tracings of the protrusive movements were analysed using a digitizer and specially designed software. A statistically significant increase (P < 0.05) in the values for horizontal condylar inclination (HCI) was found for both groups over the entire observation period. Group 1 showed a higher increase (P < 0.05) between the beginning of treatment and removal of the brackets, and group 2 between bracket removal and the end of retention. At the end of retention, a similar increase in HCI values was found for both groups. Over the observation period, the frequency of pathological axiographic findings decreased, which seems to be a positive effect of orthodontic treatment.

Adolescent↗

Provision of orthodontic care to adolescents in South Australia: the type, the provider, and the place of treatment.

There are many pathways involving different providers and locations that individuals may take in obtaining, orthodontic services. The aim of this study was to document the provision of orthodontic services and establish the pathways taken toward fixed orthodontic treatment by adolescents in South Australia. Data were collected on the use of orthodontic services by a cohort of adolescents enrolled in the School Dental Service at age 13 years and again at age 15 years. By age 15 years, 83.2 per cent of the adolescents had received orthodontic consultations, 27.3 per cent had received fixed orthodontic treatment and 41.4 per cent had received other forms of orthodontic treatment (extractions, space retainers or removable appliances). The majority of fixed orthodontic treatment was supplied by orthodontists in the private sector, while extractions and removable appliances were provided mainly by public sector general dentists. Most individuals used services in both the public and private sectors and the most frequent pathway taken by the adolescents receiving fixed orthodontic treatment involved consultation in both the public and private sectors, non-fixed orthodontic treatment in the public sector and fixed orthodontic treatment in the private sector. The findings indicate wide access to orthodontic consultation and a high uptake of fixed orthodontic treatment once the adolescent sought private sector orthodontic consultation. Orthodontic care was seen to be an interactive process between public sector general dentists and private sector orthodontists.

Adolescent↗

Orthodontic care in Sweden. Outcome in three counties.

The purpose of this series of studies was to evaluate the outcome of orthodontic care in Sweden from the professional's and the patient's perspective. In addition, a model was devised for the priority-planning of orthodontic care and for evaluating the different factors influencing the decision for orthodontic treatment. The results may be summarized as follows: Treatment Decision. Treatment desire, followed by treatment need and treatment benefit were the most important factors to consider when deciding whether or not treatment should be carried out. Regardless of the differences in resources and the structure of the free public care, a substantial proportion of the untreated 19-year-olds had malocclusions with treatment need, but they had no desire for treatment. Most of the 27-year-old individuals were satisfied with their earlier treatment decision, regardless of whether they had undergone orthodontic treatment. Dental professionals were considered to have had the greatest influence on this decision, which means that desire for treatment may be guided by the orthodontist. Individuals with malocclusions and treatment need--but who had refused proposed orthodontic treatment--were in general more discontented with their dental arrangement than other respondents, and a majority of them regretted their decision. Greater information to these individuals would have been desirable. Resources and Treatments Provided by General Practitioners or by Specialists. The sparsity of specialist resources resulted in either a greater restriction on the number necessary treatments being initiated or a greater proportion of the treatment being provided by general practitioners. In the 3 counties analysed, the treatment standard correlated well with the available resources: the greater the number of orthodontic specialists and ability to supervise the work of general practitioners and taking care of patients in need of specialist treatment, the higher the standard of treatment. Individuals treated by specialists were more contented than individuals treated by general practitioners. The measures of treatment outcome in general yielded more favourable scores for specialist treatments than for treatments provided by general practitioners, despite the specialist treatments on the average being classified as more difficult than those provided by general practitioners. Perceived treatment difficulty. About one-fourth of all treatments were classified as easy, one-fourth as moderately difficult, and one-half as difficult. The perceived treatment difficulty was associated on a group basis with the pretreatment need. The treatment investment increased and the treatment outcome became less favourable with increasing perceived difficulty. The treatment outcome was least favourable in the group where no treatment was suggested. Almost every fourth treatment was successfully carried out by mere extraction therapy. Attitudes in 27-year-olds. Orthodontic treatment was considered important by three out of four individuals, even in cases where irregularities of the teeth were small. A majority of the individuals thought that they would have been able to wear visible braces if needed, even in adult age. Methodological aspects. Studies that have used different indices to evaluate treatment outcome can only be compared with great caution. Measures with wide bases for evaluation may be more valid than measures with narrow bases. To estimate treatment outcome in terms of decrease of treatment need, the Indication Index may be recommended.

Adolescent↗