Search results for "premolar"
showing 10 items of 83 documents
Molar distalization with pendulum appliances in the mixed dentition: effects on the position of unerupted canines and premolars.
2004
Introduction: The pendulum appliance allows for rapid molar distalization without the need for patient compliance. Its efficiency has been confirmed in a number of clinical studies. However, the potential interactions and positional changes between the deciduous molars used for dental anchorage and the erupted and unerupted permanent teeth have yet to be clarified when this appliance is used for molar distalization in the mixed dentition. Methods: Twenty-nine patients in the mixed dentition each received a modified pendulum appliance with a distal screw and a preactivated pendulum spring for bilateral distalization of the maxillary molars. The patients were divided into 4 groups based on de…
Influence of first and second premolar extraction or non-extraction treatments on mandibular third molar angulation and position. A comparative study.
2009
The mandibular third molar (3M) is the tooth that is most often impacted, with lack of space being one of the reasons. In some orthodontic treatments, premolars are extracted in order to create space. The aims of our study are: firstly, to assess the changes in the angulation and position of the 3M in cases treated either with or without extraction of the first or second premolars; secondly, to analyse the variation in the gonial angle and the degree of inclusion of the 3M; and lastly, to establish a predictive impaction model for 3M. This study included 88 patients: 28 patients treated with extractions of first premolars, 30 with second premolars and 30 without. The initial and final ortho…
Tooth agenesis in a Portuguese population.
2012
Summary Objective The aim of this retrospective study was to evaluate the prevalence and pattern of hypodontia in the permanent dentition, including and excluding third molars, in a Portuguese sample. Patients and methods The study group comprised 2888 patients, observed between 2005 and 2009 at the Dentistry Clinic of the Instituto Superior de Ciencias de Saude-Norte (ISCSN, Portugal). The patients were examined for evidence of hypodontia and presence or absence of deciduous teeth in those presenting agenesis. The age range varied from 7 to 21 years. In order to study the absence of the third molar, subjects under 14 years were excluded. Statistical analysis was performed using SPSS®. Resu…
Evaluation of periimplant bone neoformation using different scanning electron microscope methods for measuring BIC. A dog study.
2012
Objetives: The aim of this study was to determine which of three methods for measuring BIC (bone-to-implant contact), using vestibular and lingual scanning electron microscopy (SEM) for different implant systems at 15, 30 and 90 days post-surgery was the most precise. An elemental analysis with SEM was used to evaluate neoformed bone composition for three implant systems at the same study times. Material and Methods: 36 implants were placed in eighteen Beagle dogs mandible about one year old and weighing approximately 12-13 kg in order to evaluate bone apposition to three different implant surfaces. It was used the third and fourth premolar and first molar distal sockets in both quadrants o…
Calculation of bone graft volume using 3D reconstruction system.
2010
Objectives: To obtain bone ?bioreplicas? for determining precisely the amount of biomaterial required for bone regeneration procedure. Study design: A case-control comparison with a total sample size of 20 cases, 10 control and 10 test samples. ?Bioreplicas? were generated from helical CAT scans with 0.5 mm slices, without 3D reconstruction or image filters. Bone defects in premolar and molar areas were treated with titanium mesh and xenograft (MP3) combined with resorbable carriers. Time taken to carry out procedures with and without the use of ?bioreplicas? (in minutes), discrepancies between the grafts performed with and without ?bioreplicas? and bone defects (mm), and postoperative comp…
3-D Evaluation of temporary skeletal anchorage sites in the maxilla
2021
Background The selection of temporary anchorage device (TAD) site can be a challenging task since one should not only consider the 2-D distances between roots, but also the entire 3-D space. Thus, the aim of this study was to evaluate the posterior maxillary region areas available for the insertion of temporary anchorage devices in reconstructed images from cone beam computed tomography (CBCT). Material and Methods Sample consisted of 72 patients with indication for orthodontic treatment, grouped into three distinct age groups: 11 to 14 years (age group 1), 15 to 19 years (age group 2) and aged 20 years or older (age group 3), which were further subdivided as to the type of malocclusion (An…
Efficacy and predictability of maxillary and mandibular expansion with the Invisalign® system
2021
Background The purpose of this study is to evaluate the efficacy and predictability of upper and lower orthodontic expansion with the Invisalign® system. Material and Methods From a sample of 167 patients; 64 upper and 51 lower arches were randomly selected from patients who had been treated with plastic orthodontics (Invisalign® aligners, SmartTrack® material). Digital models were extracted at the beginning (ModT1) and at the end of treatment (ModT2) as well as the final ClinCheck® (CkT2). The canine, premolar and molar width was measured at the gingival and cuspid level of both arches, as well as the inclination of the upper first molar. Likewise, both arches were divided regarding the pl…
An in vitro evaluation of the efficacy of a novel iontophoresis fluoride tray on remineralization
2013
Objectives: The aim of this study is to determine the effects on remineralization of a novel iontophoresis device called "Fluorinex", conventional (acidulated phosphat fluoride) APF gel treatment, and conventional ionthophoresis device comparatively by laser fluorescence measurements. Study Design: Artificial incipient carious lesions were created on immature, 60 intact premolar and molar teeth with no defects. The specimens were randomly allocated to four groups. In the first group 1.23% APF gel was applied to specimens by conventional method for 4 minutes and in the second group 2% (sodium fluoride) NaF solution applied by conventional iontophoresis device for 4 minutes. In Fluorinex grou…
Establishing a diagnostic tool for assessing optimal treatment timing in Indian children with developing malocclusions
2011
Objective: To interrelate chronological age, cervical vertebrae maturational stage and dental calcification stages and to establish latter as first level diagnostic tool to estimate timing of pubertal growth spurt. Materials and Methods: Sample derived from pretreatment panaromic and lateral cephalometric radiographs of patients 8-14 years old. Study sample divided into three groups depending upon Angle’s molar relation: Group I, Group II, Group III. According to chronological age, into: Group A: 8-11 years Group B:11-14 years, further separating males and female subjects in each group. Demirjian et al method was used to assess dental maturity and for skeletal maturity the New Improved Vers…
Rehabilitation of shortened dental arches: A fifteen-year randomised trial.
2021
Journal of oral rehabilitation 48(6), 738-744 (2021). doi:10.1111/joor.13167