Immediate vs non-immediate loading post-extractive implants: A comparative study of Implant Stability Quotient (ISQ)

Purpose. This study aims to evaluate differences in implant stability between post-extractive implants vs immediately placed post-extractive implants by resonance frequency analysis (RFA). Materials and methods. Patients were grouped into two different categories. In Group A 10 patients had an immediate postextractive implant, then a provisional, acrylic resin crown was placed (immediate loading). In Group B (control group) 10 patients only had an immediate post-extractive implant. Both upper and lower premolars were chosen as post-extractive sites. Implant Stability Quotient (ISQ) was measured thanks to RFA measurements (Osstell®). Five intervals were considered: immediately after surgery (T0) and every four weeks, until five months after implant placement (T1, T2, T3, T4,T5). A statistical analysis by means of Student’s T-test (significance set at p<0.05) for independent sample was carried out in order to compare Groups A and B. Results. The ISQ value between the two groups showed a statistically significant difference (p<0.02) at T1. No statistically significant difference in ISQ was assessed at T0, T2, T3, T4 and T5. Conclusions. After clinical assessment it is possible to confirm that provisional and immediate prosthetic surgery in postextraction sites with cone-shaped implants, platform-switching abutment and bioactive surface can facilitate osseointegration, reducing healing time

Four impacted fourth molars in a young patient: a case report

The occurrence of supernumerary teeth is a relatively uncommon dental anomaly and it's rare for patients to have impacted fourth molars in all quadrant. Aim of this work is to describe the presence of bilateral fourth molars in the maxilla and the mandible in a young male patient aged 22 years came to our hospital with acute pericoronal infection around unerupted third inferior molars. Routine radiographic examination revealed impacted inferior third molars but also unerupted bilateral upper and inferior fourth molars. The acute infection was treated by local measures and the patient was subsequently admitted for removal of third and fourth impacted upper and lower molars under general anesthesia

Prevalence, distribution, and differential diagnosis of nasopalatine duct cysts

INTRODUCTION.: Nasopalatine duct cysts (NPDCs) are the most common developmental epithelial non-odontogenic cysts of the maxillae. Their origin, however, is still a source of considerable debate. AIMS.: The aim of this investigation is to describe and discuss the etiology, differential diagnosis, clinic-pathological characteristics as well as to report the relative frequency and distribution of nasopalatine duct cysts in population (NPDCs) with a literature's review on the topic

Immediate-loading post extractive implants: indications, advantages and limits

The possibility of rehabilitating immediately an edentulous patient offers today remarkable advantages because it satisfies the patient’s demands for comfort, aesthetics, and functionality and reduces the surgical stages for the professional. In the last years clinicians and companies have been concentrating their efforts in the development of new surgical techniques and biomaterials in order to speed up the osteointegration process, which fosters the functionality, that is the immediate-loading. This clinical report, based on the analysis of the literature and on the presentation of a case report, shows how satisfying results in functionality and aesthetic can be obtained by a careful diagnosis and an accurate therapeutic planning, reducing at the same time the stress for the patient and the surgical stages for the professional. In any case, it is necessary to have the rehabilitations with immediate-loaded implants directed by workers with a good knowledge and experience in surgery, periodontology, and prosthesis or by a work team able to face all the complications such advanced rehabilitations may cause. Keywords: implants post-extraction, immediate implant

Influence of finish line in the distribution of stress trough an all ceramic implant-supported crown. A 3D finite element analysis

Influence of finish line in the distribution of stress through an all ceramic implant-supported crown. A 3D Finite Element Analysis Porpose. The aim of this study was to evaluate, by finite element analysis (FEA), the influence of finish line on stress distribution and resistance to the loads of a ZrO2 crown and porcelain in implant-supported. Material and methods. The object of this analysis consisted of a fxture, an abutment, a passing screw, a layer of cement, a framework crown, a feldspatic porcelain veneering. The abutment’s marginal design was used in 3 different types of preparation: feather edge, slight chamfer and 50°, each of them was of 1 mm depth over the entire circumference. The ZrO2Y-TZP coping was 0.6 mm thick. Two material matching for the abutment and the framework was used for the simulations: ZrO2 framework and ZrO2 abutment, ZrO2 framework and T abutment. A 600 N axial force distributed over the entire surface of the crown was applied. The numerical simulations with finite elements were used to verify the different distribution of equivalent von Mises stress for three different geometries of abutment and framework. Results. Slight chamfer on the matching ZrO2 - ZrO2 is the geometry with minimum equivalent stress of von Mises. Even for T abutment and ZrO2 framework slight chamfer is the best configuration to minimize the localized stress. Geometry that has the highest average stress is one with abutment at 50°, we see a downward trend for all three configurations using only zirconium for both components. Conclusions. Finite element analysis. performed for the manifacturing of implant-supported crown, gives exact geometric guide lines about the choice of chamfer preparation, while the analysis of other marginal geometries suggests a possible improved behavior of the mating between ZrO2 abutment and ZrO2 coping. for three different geometries of the abutment and the coping. KEY WORDS: zirconium dioxide, finite element method, implant supported restoration, marginal design. diossido di zirconio, metodo degli elementi finiti, corona implanto supportata, disegno marginale

Strength of zirconia fixed partial dentures: review of the literature

Objective: The aim of this study is a systematic review of the literature on the strength and long-term behavior of zirconia FPDs. Methods: The literature search was performed using as the primary source the Medline database. Were also imposed a set of inclusion and exclusion criteria in order to narrow the search to differentiate the two distinct parts in which it was structured the review. In addition, MeSH terms were applied to further refine the choice of articles more relevant to the review. In the part of the review concerning the long-term behavior of zirconia fixed partial dentures were considered useful only those studies with a minimum follow-up of one year. Results: The search provided a total of 813 articles, but only 25 were considered for the review because they were the only ones who satisfied search criteria. In particular, 13 items relate to the mechanical strength of zirconia prostheses and 12 regarding the long term behavior of zirconia FPDs. The resistance values also exceed the 2000 N while the survival rate reaches to almost 94%. Conclusions: Based on this review, Zirconia FPDs can be considered reliable products in both the anterior and posterior fields with survival rates comparable to traditional metal-ceramic prostheses

[Impression materials. Dimensional stability after pouring]

The Authors wanted to establish which could be for every impression material tested, the most favourable moment for the development of plaster models in a steady environment conditions of temperature and relative humidity. From the analysis of the results obtained, we can clearly conclude that every material examined offers an ideal time interval in which we have to cast the model in plaster. This study aspires to be an invitation to all operator in the sector, to repeat this experience in their work environment to know and better manage the procedures and the materials used, from the taking the impression to the executing of the plaster model