Agreement in the determination of preformed wire shape templates on plaster models and customized digital arch form diagrams on digital models.

Introduction: The aim of this study was to verify the accuracy of preformed wire shape templates on plaster models and those of customized digital arch form diagrams on digital models.

Methods: Twenty pairs of dental plaster models were randomly selected from the archives of the Department of Orthodontics of Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. All plaster model samples were scanned in a plaster model scanner to create the respective digital models.

Accuracy of printed dental models made with 2 prototype technologies and different designs of model bases.

Introduction: The aim of this study was to compare the accuracy of printed models from intraoral scans with different designs of model bases, using 2 types of 3-dimensional printing techniques.

Methods: Three types of model base design were created: regular base, horseshoe-shaped base, and horseshoe-shaped base with a bar connecting the posterior region. The digital models were printed with the 3-dimensional printers using different techniques: stereolithography and triple jetting technology (polyjet).

Are there differences between comparison methods used to evaluate the accuracy and reliability of digital models?

Objectives: The accuracy and reliability of plaster models and digital models acquired with two different surface laser scanners were tested by means of three methods: measurement with calipers, digital measurement with proper software and superimposition of the digital models.

Methods: Thirty plaster models with permanent dentition that met the inclusion criteria were selected and scanned with two laser scanners (R700 and Xcad). Three examiners measured distances on plaster models with a digital caliper and on digital models using Ortho Analyzer software.

Accuracy of stereolithographically printed digital models compared to plaster models.

Objective: This study compared the accuracy of plaster models from alginate impressions and printed models from intraoral scanning.

Materials And Methods: A total of 28 volunteers were selected and alginate impressions and intraoral scans were used to make plaster models and digital models of their dentition, respectively. The digital models were printed using a stereolithographic (SLA) 3D printer with a horseshoe-shaped design.

Accuracy and reproducibility of measurements on plaster models and digital models created using an intraoral scanner.

Aim: The purpose of the present study was to evaluate the accuracy and reproducibility of measurements made on digital models created using an intraoral color scanner compared to measurements on dental plaster models.

Methods: This study included impressions of 28 volunteers. Alginate impressions were used to make plaster models, and each volunteers' dentition was scanned with a TRIOS Color intraoral scanner.

Effect of polyvinylsiloxane material and impression handling on the accuracy of digital models.

Introduction: The objective of this study was to evaluate the accuracy and reliability of measurements on digital models obtained by scanning impressions 5, 10, and 15 days after they were made from 2 soft putty polyvinylsiloxane (PVS) materials.

Methods: Thirty volunteers were selected for making impressions of their dentitions with alginate to create a plaster model and with PVS impression material to create a digital model by laser scanning. Three examiners made the plaster model measurements with digital calipers and repeated these measurements on the digital models made from the scanned PVS impressions.

Posttreatment stability in Class II nonextraction and maxillary premolar extraction protocols.

Aim: To cephalometrically compare the overjet, overbite, and molar and canine relationship stability of Class II malocclusion treatment with and without maxillary premolar extractions.

Method: Two groups of 30 patients each with pre- and posttreatment matching characteristics and satisfactory finishing were used. Group 1 consisted of 30 patients treated with nonextraction at a mean pretreatment age of 12.

Treatment stability in patients with Class II malocclusion treated with 2 maxillary premolar extractions or without extractions.

Introduction: The purpose of this study was to compare the occlusal stability of Class II malocclusion treatment with and without extraction of 2 maxillary premolars.

Methods: A sample of 59 records from patients with complete Class II malocclusion was used. This sample was divided into 2 groups with the following characteristics: group 1, comprising 29 patients treated without extractions, and group 2, comprising 30 patients treated with extraction of 2 maxillary premolars.

Treatment of a Class II subdivision malocclusion with multiple congenitally missing teeth.

This case report describes the treatment of a patient with a Class II Division 1 subdivision right malocclusion with 8 congenitally missing teeth, incompetent lips, and incisor protrusion. The treatment plan included extractions and space closure with retraction of the anterior teeth; symmetric mechanics were used in the mandibular arch and asymmetric mechanics in the maxillary arch. Because of the mechanics used, some midline deviations were expected.