Pulp analysis of teeth submitted to different types of forces: a histological study in rats.

Objective: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces.

Material And Methods: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations.

Validation of a new experimental model of extrusive luxation on maxillary molars of rats: a histological study.

Background/aim: The aim of this study was to test and validate a new model of extrusive luxation trauma on maxillary first molars of rats.

Material And Methods: Forty adult male rats (Rattus norvegicus albinus, Wistar; weight = 230-250 g), 45 days old, were divided into eight groups (n = 5): control groups, in which animals were not subjected to any procedure and waited 1 day (GC1D) or 3 days (GC3D) for euthanasia, and experimental groups, in which animals were subjected to forces of 1100cN, 1300cN, or 1500cN and waited 1 or 3 days for euthanasia (GT1100/1D, GT1100/3D, GT1300/1D, GT1300/3D, GT1500/1D, GT1500/3D). In animals of the experimental groups, trauma was produced by an extrusive force in maxillary first right molars.

Prevalence of Dental Anomalies in Permanent Dentition of Brazilian Individuals with Down Syndrome.

Objective: The aim of this study was to evaluate the incidence of dental anomalies in the permanent dentition of individuals with Down Syndrome (DS) to increase the knowledge on the dental issues in this syndrome.

Method: One hundred and five panoramic X-rays of patients with DS (61 males and 44 females), aged 7 to 42 years were used. The data were statistically analyzed using bivariate analyses test ( <0.

Case Report of Posterior Crossbite: Description of an Effective Treatment Protocol.

Early treatment of functional unilateral posterior crossbite during the mixed dentition stage is extremely important, as it provides the correct positioning of osseous bases, teeth, and the temporomandibular joint when the stomatognathic system is in growth and development. This article reports on a 9-year-old patient who presented with functional unilateral posterior crossbite and was treated with a modified Hyrax expander. The case report highlights a simple, low-cost, effective treatment protocol.

Effect of alendronate sodium on tooth movement in ovariectomized rats.

Objectives: The aim of the present study was to evaluate the effect of two different dosages of alendronate on induced orthodontic movement in an experimental model involving rats with osteoporosis following ovariectomy.

Design: Female Wistar rats (Rattus norvegicus) eight weeks of age were divided into four groups (n=12/group): ovariectomized (OVX group); ovariectomized and treated with alendronate sodium at 1mg/kg (Group OVX+ALN1); ovariectomized and treated with alendronate sodium at 2mg/kg (Group OVX+ALN2); and sham operated (control). Three months after ovariectomy, the maxillary right first molar was submitted to movement for five and seven days.

Analysis of mesiodistal angulations of preadjusted brackets.

Manufacturers offer various prescriptions of preadjusted brackets for use in the "straight-wire" orthodontic technique. However, the need to incorporate bends in the rectangular wires during orthodontic finishing has led to concerns regarding the type of prescription chosen and the credibility of information provided by the manufacturer. The aim of this study was to compare the slot angulations of Roth prescription preadjusted metallic brackets for the maxillary left central incisor and maxillary left canine.

Resorption of roots of different dimension induced by different types of forces.

Root resorption is a variable to be considered in induced tooth movement (ITM). It is related to root morphology and alveolar bone crest, and also to the types of forces exerted by mechanotherapy. This histometric study evaluated the predominance of root resorption among roots of different dimensions, following ITM with different types of forces and at different time intervals.

Microscopic evaluation of induced tooth movement after subluxation trauma: an experimental study in rats.

Objective: The objective of this study was to assess the histological alterations that occurred in the periodontal area of rat molars submitted to induced tooth movement (ITM) right after an intentional trauma (subluxation).

Methods: Forty adult male Wistar rats (Rattus norvegicus albinus) were selected. The animals were divided into eight groups (n=5), according to the combination of variables: Group 1--control (neither trauma nor ITM); Group 2--ITM; Groups 3, 4, 5 and 6--dentoalveolar trauma groups corresponding, respectively, to 1, 3, 8 and 10 days after trauma; Groups 7 and 8 - the animals' molars were subjected to a 900 cN impact and, one and three days after the trauma event, tooth movement was induced.

Induction of ankylosis in the incisor for orthodontic tooth movement in rats.

Background/aim: The present research evaluated the induction of ankylosis and the eruption rate in rat incisors, with the aim of achieving stable anchorage for orthodontic tooth movement (OTM) of the molars.

Material And Methods: Fifteen male Wistar rats were used. In the Experimental group, the right superior incisor of each animal was extracted, denuded of the PDL and the dental papilla, and reimplanted.

Importance of periodontal ligament thickness.

This study evaluated whether periodontal ligament (PL) thickness varied with root size and examined the possible influence of this variation on orthodontic mechanics. Measurements were taken of the maxillary left first molar in 54 male Wistar rats. Mean mesial and distal PL thicknesses were compared between the intermediate buccal and mesiobuccal roots using paired Student's t-tests with a 5% significance level.

Interceptive approach to treatment of impacted maxillary canines.

Impaction of maxillary canines can be prevented by early intervention in the mixed dentition phase after the correct diagnosis of malocclusion, reducing the complexity of the treatment. This article reports the case of a 10-year-old patient who possessed impacted maxillary canines and, after early extraction of primary canines, had reestablished favorable permanent successors' eruption axis. This 5-year radiographic follow-up study with panoramic radiography shows that this can be used in practice and that an effective control strategy ensures the accuracy in the inclination of the impacted canines.

Microscopic evaluation of induced tooth movement in traumatized teeth: an experimental study in rats.

The clinical management of orthodontic patients with dental trauma before or during the treatment is mainly founded on clinical experience, expert opinions, and individual case reports. It is proposed in the literature that teeth sustaining mild trauma with minor damage to the periodontium (e.g.

Effect of heat treatment on stainless steel orthodontic wires.

This study evaluated the effect of heat treatment on CrNi stainless steel orthodontic archwires. Half of forty archwires of each thickness - 0.014" (0.

Perceptions of laypersons and orthodontists regarding the buccal corridor in long- and short-face individuals.

Objective: To determine the perception of orthodontists and laypersons regarding the size of the dark spaces in the buccal corridors and how that affects smile esthetics in individuals with long and short faces.

Materials And Methods: Images of eight smiling individuals were modified to create five sizes of dark spaces in the buccal corridors (2%, 10%, 15%, 22%, and 28%) and were submitted to a group of laypersons and a group of orthodontists.

Results: Laypersons were more critical in their evaluation than orthodontists.

Multidisciplinary treatment of a fractured root: a case report.

Aim: To describe the orthodontic, periodontal and prosthetic management of a case with a 3 mm root fracture below the crest of the alveolar bone.

Methods: The root was extruded and periodontal surgery carried out to improve aesthetics and dental function.

Conclusion: A multidisciplinary approach to the management of dental root fractures is necessary for successful treatment.

Knowledge on dental trauma and orthodontic tooth movement held by a group of orthodontists.

The objective of this work was to assess the knowledge about orthodontic tooth movement and dental trauma held by a group of orthodontists in specific areas of Brazil. For this purpose, 166 questionnaires with 15 objective questions about this subject were distributed. One hundred and five questionnaires were properly filled and collected after 30 days.

Mesiodistal angulations of the mandibular canines, premolars and molars with or without the presence of third molars.

The purpose of the present research was to compare the normal average values of mesiodistal axial angulation, with the mesiodistal axial angulation of canines, premolars and mandibular molars in individuals with and without the presence of the mandibular third molars. Panoramic radiographs of 19 male and 21 female Caucasians, with a mean age of 22.35 years, who had not undergone orthodontic treatment were studied.

Histological evaluation of experimentally induced subluxation in rat molars and its implications on the management of orthodontic treatment.

The purpose of this study was to evaluate the histological alterations occurred in the periradicular region of rat molars after intentional subluxation using an experimental method to induce dentoalveolar trauma. Eighteen adult male Wistar rats (Rattus norvegicus albinus) were selected for the study. The dentoalveolar trauma was experimentally induced by the application of an occlusogingival force on the occlusal surface of the maxillary right first molar using a tensiometer secured on a fully articulated support with adjustable steel shafts.

Compensatory canine angulation in angle Class II and III patients.

The aim of this study was to evaluate the occurence of compensation in mesiodistal axial inclinations of canines in skeletal malocclusions patients. The sample consisted of 25 Angle Class II, division 1 malocclusion (group 1) and 19 Angle Class III malocclusion patients (group 2). After measurement of dental angulations through a method that associates plaster model photography and AutoCad software, comparisons between the groups were performed by T-test for independent samples.