Acurácia de implantes imediatos instalados com cirurgia guiada ou convencional na região anterior de acordo com a experiência do cirurgião: estudo in vitro / Accuracy of immediate implants installed with guided or conventional surgery in the previous region according to the surgeon's experience: in vitro study

O objetivo deste estudo foi avaliar acurácia do posicionamento de implantes imediatos instalados na região anterior da maxila por meio de cirurgia guiada ou convencional de acordo com a experiência do cirurgião. Dez cirurgiões inexperientes e 10 cirurgiões experientes instalaram em modelos odontológico, um implante de forma guiada e convencional na região do dente 12 e 22, distribuídos aleatoriamente. A amostra foi composta por 4 grupos: experiente e guiado (EG), experiente e convencional (EC), inexperiente e guiado (IG) e inexperiente e convencional (IC) com 10 casos em cada grupo, totalizando 40 implantes. Foram impressos 20 modelos obtidos a partir do escaneamento de um manequim de treinamento padronizado (MOM). O modelo foi submetido a tomografia por feixe cônico e escaneado para planejamento da posição ideal do implante e obtenção das guias cirúrgicas, utilizando o software coDiagnostiX®. Após a instalação dos implantes foram obtidas novas tomografias dos modelos e a acurácia do posicionamento foi comparada ao planejamento inicial por meio da sobreposição das imagens nos sentidos global, e linear. Os dados obtidos foram tabulados e submetidos à análise estatística. Observamos diferenças estatísticas entre o tipo de cirurgia no grupo experiente no desvio angular e nos desvios lineares: plataforma tridimensional (P-3D), mesio distal (P-MD), vestíbulo palatino (P-VP),apical tridimensional (A-3D), mesio distal (A-MD), vestíbulo palatino (A-VP) e no grupodos cirurgiões inexperientes nos desvios lineares P-3D, P-MD, P-VP, A-3D, A-MD. Ao comparar a acurácia de acordo com a experiência do cirurgião, observamos diferenças significativas apenas na cirurgia convencional para os desvios de P-3D, PAC e A-AC. Concluímos que a acurácia dos implantes instalados de forma guiada foi maior independentemente do grau de experiência do cirurgião. (AU)

The objective of this study was to evaluate the accuracy of the positioning of immediate implants installed in the anterior region of the maxilla through guided or conventional surgery, according to the surgeon's experience. Ten inexperienced surgeons and 10 experienced surgeons installed, in dental models, an implant in a guided and conventional way in the region of tooth 12 and 22, randomly distributed. The sample consisted of 4 groups: experienced and guided (EG), experienced and conventional (EC), inexperienced and guided (IG) and inexperienced and conventional (IC) with 10 cases in each group, totaling 40 implants. Twenty models obtained from the scanning of a standardized training manikin (MOM) were printed. The model was submitted to cone beam tomography and scanned to plan the ideal position of the implant and obtain the surgical guides, using the coDiagnostiX® software. After implant placement, new tomography scans of the models were obtained and the positioning accuracy was compared to the initial planning by superimposing the images in the global and linear directions. The data obtained were tabulated and submitted to statistical analysis. We observed statistical differences between the type of surgery in the group experienced in angular deviation and linear deviations: three-dimensional platform (P-3D), mesiodistal (P-MD), palatal vestibule (P-VP), three-dimensional apical (A-3D), mesiodistal (A-MD), vestibule palatine (A-VP) and in the group of inexperienced surgeons in linear deviations P-3D, P-MD, P-VP, A-3D, A-MD. When comparing the accuracy according to the surgeon's experience, we observed significant differences only in conventional surgery for P-3D, P-AC and A-AC deviations. We concluded that the accuracy of guided implants was higher regardless of the surgeon's experience. (AU)

Surface detail reproduction and dimensional accuracy of molds: influence of disinfectant solutions and elastomeric impression materials.

This study compared the surface detail reproduction and dimensional accuracy of molds after disinfection using 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to those of molds that were not disinfected, for four elastomeric impression materials: polysulfide (Light Bodied Permlastic), polyether (Impregum Soft), polydimethylsiloxane (Oranwash L) andpolyvinylsiloxane (Aquasil Ultra LV). The molds were prepared on a matrix by applying pressure, using a perforated metal tray. The molds were removed following polymerization and either disinfected (by soaking in one of the solutions for 15 minutes) or not disinfected. The samples were thus divided into 16 groups (n=5). Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy to assess the 20-µm line over its entire 25 mm length. The dimensional accuracy results (%) were subjected to analysis of variance (ANOVA) and the means were compared by Tukey's test (a=5%). The 20-µm line was completely reproduced by all elastomeric impression materials, regardless of disinfection procedure. There was no significant difference between the control group and molds disinfected with peracetic acid for the elastomeric materials Impregum Soft (polyether) and Aquasil Ultra LV (polyvinylsiloxane). The high-level disinfectant peracetic acid would be the choice material for disinfection.

Este estudo comparou a reprodução de detalhes da superficie e estabilidade dimensional de moldes obtidos após desinfecção utilizando hipoclorito de sódio 2%, digluconato de clorexidina 2%, ou ácido peracético 0,2% a moldes que não foram desinfetados com quatro elastomeros: polissulfeto (Light Bodied Permlastic), polieter (Impregum Soft), silicona reação por condensação (Oranwash L) e silicona reação por adição (Aquasil Ultra LV). Os moldes foram preparados sobre matriz contendo linhas de 20, 50 e 75 µm realizado sob pressão com moldeira de metal perfurada. Os moldes foram removidos após a polimerização e desinfetados (utilizando uma das soluções por imersão, armazenados em frascos fechados durante 15 minutos) ou não desinfetados. Assim, as amostras foram divididas em 16 grupos (n=5). A reprodução detalhes da superficie e a precisão dimensional foram avaliadas usando microscopia óptica na linha 20 µm com 25 mm de comprimento, de acordo com a norma ISO 4823. Os resultados de precisão dimensional (%) foram submetidos a análise de variancia (ANOVA) e as médias comparadas pelo teste de Tukey com 5% de nivel de significancia. A linha de 20 µm foi completamente reproduzida por todos os elastomeros, independentemente do processo de desinfecção. Nao houve diferenga estatisticamente significativa entre o grupo controle e moldes desinfetados com acido peracético para os elastomeros Impregum Soft (polieter) e Aquasil Ultra LV (silicona reação por adição). O desinfetante de alto nivel ácido peracético seria o material de escolha para a desinfecção.

Surface detail reproduction and dimensional accuracy of molds: influence of disinfectant solutions and elastomeric impression materials / Reprodução de detalhes da superfície e estabilidadedimensional de moldes: influência das soluçõesdesinfetantes e elastômeros

This study compared the surface detail reproduction anddimensional accuracy of molds after disinfection using 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to those of molds that were not disinfected, forfour elastomeric impression materials: polysulfide (Light Bodied Permlastic), polyether (Impregum Soft), polydimethylsiloxane(Oranwash L) and polyvinylsiloxane (Aquasil Ultra LV). Themolds were prepared on a matrix by applying pressure, using aperforated metal tray. The molds were removed followingpolymerization and either disinfected (by soaking in one of thesolutions for 15 minutes) or not disinfected. The samples werethus divided into 16 groups (n=5). Surface detail reproductionand dimensional accuracy were evaluated using opticalmicroscopy to assess the 20 ­µm line over its entire 25 mm length. The dimensional accuracy results (%) were subjectedto analysis of variance (ANOVA) and the means were comparedby Tukey’s test (α=5%). The 20 ­µm line was completelyreproduced by all elastomeric impression materials, regardlessof disinfection procedure. There was no significant difference between the control group and molds disinfected with peraceticacid for the elastomeric materials Impregum Soft (polyether)and Aquasil Ultra LV (polyvinylsiloxane). The high­leveldisinfectant peracetic acid would be the choice material for disinfection.

Este estudo comparou a reprodução de detalhes da superfície e estabilidade dimensional de moldes obtidos após desinfecção utilizando hipoclorito de sódio 2%, digluconato de clorexidina 2%, ou ácido peracético 0,2% a moldes que não foram desinfetados com quatro elastômeros: polissulfeto (Light Bodied Permlastic), polieter (Impregum Soft), silicona reação porcondensação (Oranwash L) e silicona reação por adição (Aquasil Ultra LV). Os moldes foram preparados sobre matriz conten dolinhas de 20, 50 e 75 µm realizado sob pressão com moldeirade metal perfurada. Os moldes foram removidos após a polimerização e desinfetados (utilizando uma das soluções porimersão, armazenados em frascos fechados durante 15 minutos)ou não desinfetados. Assim, as amostras foram divididas em 16grupos (n=5). A reprodução detalhes da superfície e a precisão dimensional foram avaliadas usando microscopia óptica na linha 20 µm com 25 mm de comprimento, de acordo com a norma ISO 4823. Os resultados de precisão dimensional (%) foram submetidos à análise de variância (A NOVA) e as médias comparadas pelo teste de Tukey com 5% de nível de significância. A linha de 20 µm foi completamente reproduzida por todos os elastômeros, independentemente do processo de desinfecção. Não houve diferença estatisticamente significativa entre o grupo controle e moldes desinfetados com acido peracético para os elastômeros Impregum Soft (polieter) e Aquasil Ultra LV (siliconareação por adição). O desinfetante de alto nível ácido peracético seria o material de escolha para a desinfecção.

Effect of different impression techniques and elastomeric impression materials on the dimensional accuracy of partially edentulous mandibular arch

Aim: Evaluate the dimensional accuracy of stone casts of a partially edentulous mandibular arch made by two impression techniques (1-step putty/light-body and 2-step putty/light-body) using addition and condensation silicones. Methods: A partially edentulous steel stainless cast with four markings on teeth 33, 37, 43, and 47 was used to obtain the impressions. The transverse (33-43 and 37-47) and anteroposterior (33-37 and 43-47) distances were measured by measuring microscope (30x magnification; 0.5µm accuracy). For the 1-step putty/light-body technique, both viscosities of the impression materials were handled together. For the 2-step putty/light-body technique, the impression materials of different viscosities were handled separately and a polypropylene spacer (2 mm thick) was used to create a relief. The same distances were measured on stone casts (n = 5). The values were submitted to normality test (Kolmogorov-Smirnov) and analyzed statistically by three-way ANOVA and Tukey's (5%). Results: All distances showed shrinkage (negative linear changes). The addition silicones showed better accuracy than condensation silicones (p<0.05) and no significant difference was found between the impression techniques (p>0.05). The edentulous zone (43-47) presented worst dimensional accuracy results. Conclusions: The accuracy of the casts is more related to the impression material than impression technique. (AU)

Dimensional Accuracy of Stone Casts Made from Silicone-Based Impression Materials and Three Impression Techniques

The aim of this study was to measure and compare the dimensional accuracy of stone casts of a partially edentulous mandibular arch made by two condensation silicones, two addition silicones and three impression techniques (1-step putty/light-body, 2-step putty/light-body and monophase technique). A partially edentulous standard stainless steel mandibular arch cast was obtained with reference points on the permanent mandibular right and left canines, and permanent mandibular right and left second molars. The anteroposterior distances (between the mandibular left canine and second molar and between the mandibular right canine and second molar) and transverse distances (between the mandibular left and right canines and between the mandibular left and right second molars) of stainless steel cast were measured by a microscope at 30× magnification and 0.5 µm accuracy. All impressions were made with condensation or addition silicones. The 1- and 2-step putty/light-body impressions were accomplished with putty and light-body materials and the monophase impressions with light-body material only. After the impression procedures, accuracy of each material and technique was assessed measuring the stone casts poured (n=5) from the impressions, by the same microscope. The differences between the values of stone cast and stainless steel cast were calculated, presented as percentages and analyzed statistically by two-way ANOVA and the means compared by Tukey's test (α=0.05). All distances measured on stone casts showed altered dimensions with significantly negative linear changes (shrinkage) as compared to those of the stainless steel cast. The stone casts made from the addition silicones were dimensionally more accurate. No differences were found among the impression techniques.

O objetivo deste estudo foi mensurar e comparar a precisão dimensional de modelos de gesso de um arco mandibular parcialmente edêntulo feitos a partir de dois silicones por condensação, dois silicones por adição e três técnicas de moldagem (dupla mistura, reembasamento e moldeira individual). Um modelo metálico padrão de um arco mandibular parcialmente edêntulo foi obtido com pontos de referência nos caninos mandibulares permanentes esquerdo e direito, e segundo molares mandibulares permanentes esquerdo e direito. As distâncias anteroposteriores (entre o canino e segundo molar mandibulares esquerdos e entre o canino e segundo molar mandibulares direitos) e as distâncias transversais (entre os caninos mandibulares esquerdo e direito e entre os segundos molares mandibulares esquerdo e direito) do modelo metálico foram mensuradas através de um microscópio com 30x de aumento e 0,5 µm de precisão. Todas moldagens foram feitas com silicones por condensação e adição. As técnicas de dupla mistura e reembasamento foram realizadas com materiais nas viscosidades massa e leve e a técnica da moldeira individual somente com material leve. Após os procedimentos de moldagem, a precisão de cada material e técnica foi aferida medindo os modelos de gesso vazados (n=5) dos moldes, sob o mesmo microscópio. As diferenças entre os valores dos modelos de gesso e do modelo metálico foram calculadas, apresentadas como porcentagens e analisadas estatisticamente através da análise de variância e teste de Tukey (α=0,05). Todas as distâncias mensuradas nos modelos de gesso apresentaram dimensões alteradas com alterações lineares negativas (contração) significativas quando comparadas as medidas do modelo metálico. Os modelos de gesso feitos a partir de silicones por adição foram dimensionalmente mais precisos. Não foram encontradas diferenças entre as técnicas de moldagem.

Surface detail reproduction and dimensional accuracy of stone models: influence of disinfectant solutions and alginate impression materials

This study compared the surface detail reproduction and dimensional accuracy of stone models obtained from molds disinfected with 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to models produced using molds which were not disinfected, with 3 alginate materials (Cavex ColorChange, Hydrogum 5 and Jeltrate Plus). The molds were prepared over matrix containing 20-, 50-, and 75-µm lines, performed under pressure with perforated metal tray. The molds were removed following gelation and either disinfected (using one of the solutions by spraying followed by storage in closed jars for 15 min) or not disinfected. The samples were divided into 12 groups (n=5). Molds were filled with dental gypsum Durone IV and 1 h after the start of the stone mixing the models were separated from the tray. Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy on the 50-µm line with 25 mm in length, in accordance with the ISO 1563 standard. The dimensional accuracy results (%) were subjected to ANOVA. The 50 µm-line was completely reproduced by all alginate impression materials regardless of the disinfection procedure. There was no statistically significant difference in the mean values of dimensional accuracy in combinations between disinfectant procedure and alginate impression material (p=0.2130) or for independent factors. The disinfectant solutions and alginate materials used in this study are no factors of choice regarding the surface detail reproduction and dimensional accuracy of stone models.

Este estudo comparou a reprodução de detalhes da superfície e alteração dimensional de modelos de gesso obtidos a partir de moldes desinfetados com hipoclorito de sódio 2%, digluconato de clorexidina 2%, ou ácido peracético 0,2% a modelos confeccionados utilizando moldes que não foram desinfetados com três alginatos (Cavex ColorChange, Hydrogum 5, Jeltrate Plus). Os moldes foram preparados sobre matriz contendo linhas de 20, 50 e 75 µm realizado sob pressão com moldeira de metal perfurada. Os moldes foram removidos após a geleificação e desinfetados (utilizando uma das soluções por pulverização, armazenados em frascos fechados durante 15 min) ou não desinfetados. Assim, as amostras foram divididas em 12 grupos (n=5). Os moldes foram preenchidos com gesso dental Durone IV e uma hora após a manipulação do gesso os modelos foram separados da moldeira. A reprodução de detalhes da superfície e a precisão dimensional foram avaliadas usando microscopia óptica na linha 50 µm com 25 mm de comprimento, de acordo com a norma ISO 1563. Os resultados de precisão dimensional (%) foram submetidos à ANOVA. A linha de 50 µm foi completamente reproduzida por todos os alginatos, independentemente do processo de desinfecção. Não houve diferença estatisticamente significativa nos valores médios de precisão dimensional nas combinações entre procedimento de desinfecção e alginato (p=0,2130), ou para fatores independentes. Soluções desinfetantes e alginatos utilizados neste estudo não são fatores de escolha em relação à reprodução de detalhes da superfície e alteração dimensional de modelos de gesso.

Dimensional accuracy of stone casts made by a monophase impression technique using different elastomeric impression materials

Impression taking is a critical step in the process of producing successful crowns and fixed partial dentures in oral rehabilitation, and the impression material is an important factor related to clinical success. Aim: The aim of this in vitro study was to assess and compare the dimensional accuracy of stone casts made from a monophase technique using 10 elastomeric impression materials. Methods: First, a stainless steel model with reference points in the teeth 33, 43, 37, and 47 was used to obtain the impressions. The distances were measured among teeth 33-43, 37-47, 33-37, and 43-47. For the impression technique, acrylic resin trays were made with an internal relief of approximately 2 mm. Specific adhesives for each material were used in the custom trays. Tray detachment movement was standardized by pneumatic equipment. After the impression procedures and obtaining of samples, the stone casts were observed in a measuring microscope at 30x magnification. Data recorded for each distance were analyzed statistically by one-way analysis of variance and Tukey’s test at 5% significance level. Results: Stone casts made with elastomeric impression materials showed statistically significant (p<0.05) differences when the dimensional accuracy values were compared. The order for the highest to lowest accuracy for the types of impression materials was as follws: polyvinylsiloxane (PVS), polyether, polysulfide and polydimethylsiloxane (PDMS). Conclusions: PVS were the most dimensionally accurate impression materials, and the PDMS showed the worst results of dimensional accuracy.

Effect of cervical relining of acrylic resin copings on the accuracy of stone dies obtained using a polyether impression material

The purpose of this study was to evaluate the accuracy of the respective dies after polyether elastomeric procedure in the presence or absence of cervical contact of the acrylic resin shell with the cervical region, establishing a comparison to dies obtained with stock trays. This study consisted of three groups with 10 specimens each: 1) acrylic copings without cervical contact, (cn); 2) acrylic copings with cervical contact (cc); 3) perforated stock tray, (st). The accuracy of the resulting dies was verified with the aid of a master crown, precisely fit to the master steel die. ANOVA test found statistically significant differences among groups (p<0.001). Tukey's test found that the smallest discrepancy occurred in group cn, followed by cc, while the st group presented the highest difference (cc x cn: p=0.007; st x cn: p<0.001; st x cc: p<0.001).