It can be concluded that the tissue of the guide support influences the accuracy of computer-aided implant surgery.

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Background Technology advancement has rising in the past decade and brought several innovations and improvements. In dentistry, this advances provided more comfortable and quick procedures to both the patient and the dental surgeon, generating less predictability in the final result. Several techniques has been developed for the preparation of surgical guides aiming at the optimization of surgical procedures. The present study aimed to evaluate the reproducibility and precision of two types of surgical guides obtained using 3D printing and milling methods. Methods A virtual model was developed that allowed the virtual design of milled (n = 10) or 3D printed (n = 10) surgical guides. The surgical guides were digitally oriented and overlapped on the virtual model. For the milling guides, the Sirona Dentsply system was used, while the 3D printing guides were produced using EnvisionTEC’s Perfactory P4K Life Series 3D printer and E-Guide Tint, a biocompatible Class I certified material. The precision and trueness of each group during overlap were assessed. The data were analyzed with GraphPad software using the Kolmogorov–Smirnov test for normality and Student’s t test for the variables. Results The Kolmogorov–Smirnov test showed a normal distribution of the data. Comparisons between groups showed no statistically significant differences for trueness (p = 0.529) or precision (p = 0.3021). However, a significant difference was observed in the standard deviation of mismatches regarding accuracy from the master model (p < 0.0001). Conclusions Within the limits of this study, surgical guides fabricated by milling or prototyped processes achieved similar results.

The purpose of this study was to compare the accuracy of stereolithographic casts (SCs) with those obtained using conventional implant impressions. An epoxy resin model containing dental implants was used as master model. Dental casts (n = 10) were fabricated through both conventional and digital implant impressions. The conventional casts (CCs), SCs, and the master model were digitized, and the accuracy was determined through a deviation analysis and linear measurements. Data were analyzed using paired Student t test with P &lt; .05. The SCs showed higher deviation at the vestibular area (CC: 41 ± 28.87 μm; SC: 117 ± 36.83 μm) and lingual cusps (CC: 40.70 ± 19.79 μm; SC: 80 ± 42.95 μm) in comparison with CCs. No statistically significant difference was found for linear measurements of conventional and digital casts. The entire-arch accuracy was comparable between casts. However, SCs were less accurate at the cusp level in comparison with CCs.

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Bone grafting provides ideal conditions to the patient's rehabilitation with dental implants. In addition, prototyped tridimensional models allow the surgical procedure to be simulated and enable important anatomic structures to be visualized. To present a bone defect rehabilitated with xenogenic bone preshaped on a stereolithographic model and the follow-up after 7 years of treatment. The present case report describes a bone defect rehabilitated with a lyophilized bone block preshaped on a stereolithographic model. The patient, a 56-year-old woman, was referred to the dental office presenting a bone defect in the anterior maxilla. Bone regeneration intervention was performed with xenogenic grafting and barrier membrane. The follow-up of the postoperative period and after 7 years is presented. After 7 years, the tomographic exam showed the maintenance of bone at the grafted site, representing the long-term success of the treatment.

Objective: The aim of the present study was to evaluate the reproducibility and precision of two types of surgical guides, obtained by using 3D printing and milling methods. Methods: A virtual model was developed, which allowed the virtual design of surgical guide project that were milled (n = 10) or 3D printing (n = 10). Surgical guides were digitally oriented and overlapped on the virtual model that had generated them. For milling guides, it was used the Sirona Dentsply system, while 3D printing guides were produced at the Perfactory P4K Life Series, the EnvisionTEC's E-Guide Tint. In this way, average mismatches from the master model were determined. Moreover, coefficients of variation, root mean square deviations, and mismatches during an overlap were evaluated after obtaining individual misalignments for each guide, in order to verify the reproducibility of the guides and the precision of the methods for obtaining the guides Results: The evaluations showed that both groups presented the same degree of mismatch during overlap, with no statistically significant differences between the groups. However, the intragroup evaluation for misalignment, 3D printing surgical guides had a higher coefficient of variation than the milled guides, since a statistically significant difference was observed between groups in the RMS of the guide from the master model. Conclusions: Milling of the guides resulted in smaller misalignments from the master model.

Comparar a exatidão de modelos de implante prototipados em relação àqueles obtidos pela técnica de moldagem convencional. Um modelo de resina epóxica contendo 3 implantes dentais na região dos dentes 22 (1), 24 (2) e 26 (3) foi utilizado como modelo mestre. Para a técnica convencional (G1), modelos de gesso (n10) foram obtidos a partir da técnica da moldeira aberta. Para a técnica de moldagem digital (G2), corpos de escaneamento foram fixados aos implantes e o modelo mestre foi digitalizado. A confecção dos modelos (n10) foi realizada com base nas imagens virtuais, a partir da prototipagem rápida. Posteriormente, o modelo mestre, os modelos de gesso e modelos prototipados foram digitalizados com um scanner laboratorial. A discrepância média, máxima discrepância positiva e máxima discrepância negativa entre cada modelo e o modelo mestre foram determinadas, assim como a discrepância encontrada em pontos localizados de interesse (cúspide vestibular, cúspide lingual e fossa). Para a análise estatística dos dados, utilizou-se teste T de Student com nível de significância p≤ 0.05. Resultados: Não houve diferença estatisticamente significante entre a discrepância média dos modelos convencionais e prototipados. Os modelos prototipados apresentaram uma maior discrepância na região de cúspides vestibular (G1: 41 ± 28 G2: 117 ± 37 μm) e lingual (G1: 40 ± 19 G2: 80 ± 42 μm). Os modelos convencionais e prototipados apresentaram exatidão comparável. Entretanto, em pontos de interesse a discrepância foi maior para os modelos prototipados.Palavras-chave: Técnicas de Moldagem Odontológica. Próteses e Implantes. Implantes Dentários. CAD-CAM