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L’Organizzazione Mondiale della Sanità considera la salute orale come parte integrante, non solo dello stato di salute generale, ma anche della qualità della vita di ciascun individuo. In tale ottica, in accordo e con il sostegno del mondo professionale e della comunità scientifica di questo settore, le raccomandazioni cliniche in odontostomatologia contenute nel presente volume forniscono indicazioni e definiscono standard di intervento per la prevenzione e la cura delle più comuni patologie del cavo orale nonché per l’identificazione di percorsi terapeutici appropriati a supporto degli operatori pubblici e privati. Esse costituiscono, inoltre, uno strumento utile per mantenere alto il livello di qualità delle cure in questo periodo storico, nel quale, se da un lato crescono le opportunità tecniche di cura e la potenziale domanda delle stesse, dall’altro la riduzione delle risorse economiche a disposizione dei cittadini tende a limitare l’accesso all’offerta professionale privata e, al contempo, i processi di razionalizzazione dell’allocazione dei fondi nel SSN rendono più difficile l’accesso alle strutture pubbliche. L’individuazione di raccomandazioni cliniche chiaramente definite e rese pubbliche può facilitare la condivisione degli obiettivi e dei percorsi terapeutici tra odontoiatra e paziente, migliorare la comunicazione e, in ultima analisi, accrescere la fiducia sia nei riguardi del proprio specifico professionista che del “sistema delle cure” più in generale. La revisione delle “Raccomandazioni cliniche in odontostomatologia” si è resa necessaria in considerazione del cambiamento dell’evidenza scientifica, dell’immissione in commercio di nuovi materiali e dell’utilizzo di nuove tecnologie, specie in ambito protesico. Come per la precedente, alla realizzazione di questa edizione ha contribuito un ampio gruppo di docenti ed esperti delle singole branche odontoiatriche insieme alle più importanti e rappresentative Associazioni professionali e ai componenti della Commissione Albo Odontoiatri (CAO) nazionale.

Purpose: Implant impressions and working models form integratedprecision systems for registration and transmission of clinical data.The components of implant systems have a dimensional tolerancecapable of introducing inaccuracies in the impression, thus in theprostheticframework.Thisarticleaimedatcomparing2repositioningimpression techniques: one using impression copings (conventionaltechnique) and the other using the final abutments as impressioncopings (interceptive technique).Materials andMethods: Two experimentalmodels, onewith 4 par-allel implants and the other with 4 nonparallel implants, were usedto make silicone impressions. Twenty impressions were made withthe conventional technique, and a further 20 were made with theinterceptive technique. Three-dimensional images acquired with athree-dimensional scanner were measured using a three-dimensionalimage analysis software, comparing models obtained from theimpressions with the experimental models. Data were statisticallyanalyzed by means of confidence intervals calculated with themean (α = 0.05), descriptive (box plot), and bivariate analyses.Results: Statistic analysishighlighted significant differences amongmodels obtained using both techniques: the interceptive techniquegenerated working models with less distortion and variability.Conclusions: For internal-connection implants, the interceptivetechnique provided significantly more precise working models thandid the conventional technique.Key Words: Implant prosthesis, impression technique, precision,interceptive impression, internal connection(J Craniofac Surg 2014;25: 822–827)

Purpose: This study investigated the reliability of visual assessment of marginal gaps in relation to the use of magnification and the operator’s profession. Materials and Methods: A titanium bar was notched, simulating 40 marginal gaps, and 35 operators performed a quantitative evaluation of the incisions. Results: Visual examination was neither sensitive nor specific, as an extreme variability of data was recorded. The precision of readers improved with magnification aids only for clinicians; technicians were significantly more accurate in evaluating the incision’s width. Conclusion: The visual examinations were inadequate to decide the clinical acceptability of a restoration with regard to its marginal fit.

Aim This study was aimed to assess contaminants on the abutment surface close to the implant-abutment interface and the connection, after common technical protocols. Materials and methods A total of 40 abutments were divided into four groups: control group (abutment removed from the plastic envelop), test group1 (milled), test group2 (milled and polished), test group3 (milled, polished and steamed). Groups were subjected to scanning electron microscope (SEM) analysis. Pollution particles were counted and measured. Mean values and standard deviation (SD) were calculated. To evaluate any difference between groups Wilcoxon Signed Rank Test was conducted. In addition, contaminant chemical characterization was investigated by Energy-dispersive X-ray spectroscopy (EDX). Results Control group presented minimal amount of pollution (mean value of 2.1 spots [SD: 1.66] covering 0.004% of the surface). On the other hand, SEM analysis revealed on the abutment surface a mean value of 115.9 (SD: 32.27), 162 (SD: 21.17), and 32.5 (SD: 9.73) spots, respectively, in Test group 1, 2, and 3. Micro-particles covered the 0.025%, 0.057%, 0.0404% of the surface, respectively, in Test group 1, 2, and 3. On the connection, SEM analysis revealed a mean value of 61.9 (SD: 9.07), 39 (SD: 12.35), 42.1 (SD: 8.59) spots, respectively, in Test group 1, 2, and 3. Micro-particles covered the 0.0774%, 0.0869%, and 0.0392% of the surface, respectively, in Test group 1, 2, and 3. Spots were identified by EDX as micro-particles of lubricant and titanium smear layer. All differences were statistically significant. Conclusions After technical procedures, presence of contaminants on the abutment surface in contact with the peri-implant tissues was confirmed. To prevent that such debris could interfere with biological stability of peri-implant tissues and, thus, enhance the implant-prosthesis integration, different cleaning protocols should be evaluated.

Purpose: The aim of this study was to investigate if argon plasma cleaning increases the shear bond strength between zirconia and veneering ceramic surfaces. Materials and Methods: Ninety tablets of densely sintered yttriastabilized tetragonal zirconia polycrystal were divided into three groups according to cleaning treatment (steam cleaning or plasma of Argon for 375 or 750 seconds). Groups were divided into two subgroups according to the application of a ceramic liner (A = liner, B = no liner). Results: Within subgroup A, argon plasma cleaning significantly decreased shear bond strength. In subgroup B, the plasma treatment increased the shear bond strength, but the differences were not statistically significant. Subgroup A demonstrated lower shear bond strength compared to subgroup B. Conclusions: Argon plasma cleaning was suggested to improve the bond between ceramic and zirconia surfaces; however, when plasma cleaning was followed by a glassy liner application, the veneering ceramic/zirconia bond was significantly reduced

This study tested the possible damage to the internal implant connection provoked by repeated disconnection and reconnection of prosthetic components. Using a light-structured scanner, connection deformation was inferred by threedimensional (3D) positional changes of a "reference" abutment before and after multiple dis- and reconnections. Measurements were taken after 1, 2, 5, 10, and 20 insertions of titanium abutments in 16 internal hexagon implants. Statistical analysis revealed that multiple dis- and reconnections could cause a deformation in the implant-abutment connection, proportional to the number of insertion procedures. However, below the threshold of 10 cycles, 3D deformation values were minimal.

Background A lack of evidence is present in literature regarding the clinical relevance of micropollution and bacterial contamination present on customized titanium abutments following laboratory stages and steaming cleaning procedures. To preserve abutments from such pollutants, plasma of argon cleaning of customized abutments was advocated. Aim The aim of this prospective, randomized, match-paired, triple-blinded, controlled, clinical trial is to longitudinally assess radiographical marginal bone-level changes around implants restored according to the platform switching and “one-abutment-one-time” concepts, using commercially available abutments, with and without plasma of argon cleaning treatment after customization. Materials and methods Thirty patients with thin gingival biotype, a history of periodontal disease, and in general good health received one implant in the anterior maxilla or premolar region. Patients were randomly assigned to control (abutment subjected only to usually adopted cleaning protocol by steam) and test group (abutment subjected to plasma of argon treatment). Periapical standardized digital radiographs were taken at the time of crown connection (T0), 6 (T1) and 24 months after the final restoration (T2). Average mesial–distal bone-level changes mean values with standard deviations (SD) were calculated. The Mann–Whitney U-test was selected to identify differences in bone-level changes between test and control groups. Results An average interproximal bone loss of 0.16 mm (SD: 0.17) and 0.07 mm (SD: 0.34) was revealed in the control and test group at 6 months (T1), respectively, while after 24 months, groups showed a mean bone-level changes of 0.38 mm (SD: 0.44) and 0.11 mm (SD: 0.14), respectively. Statistically significant differences among control and test groups were found at both time points. Intergroup comparison relived absence of statistically significant difference. Conclusion Plasma-cleaning treatment of implant titanium abutments, together with platform switching and one-abutment-one-time concepts, could be favorable in terms of hard-tissue-level changes, also in critical conditions such as in patients with a history of periodontal disease, presenting thin gingival biotype.

PURPOSE: To compare the shear bond strength (SBS) values of resin cement to zirconia treated with a new activating method. MATERIALS AND METHODS: Forty-five zirconia specimens were divided into three groups: no treatment (group 1), plasma of argon cleaning for 375 seconds (group 2), and plasma of argon cleaning for 750 seconds (group 3). Composite cylinders were bonded with a self-adhesive cement. After 40 days of water storage, specimens were subjected to the SBS test. Data were analyzed with one-way analysis of variance and the Neuman-Keuls multiple comparison test. RESULTS: Test groups obtained SBS values significantly higher (101% for group 2 and 81% for group 3) than controls. CONCLUSION: Plasma of argon appeared to improve bonding between zirconia and resin cement.

Aim: To assess and characterize pollution micro-particles and bacterial growth on customized titanium abutments after steaming, ultrasonic and plasma cleaning treatments. Materials and methods: Thirty commercially available implant abutments, after customization, were randomly divided into 3 groups of 10 and cleansed by steam (considered as control group), ultrasonic cleaning (test group 1) and plasma of Argon (test group 2). For all specimens, SEM analysis and EDAX microanalysis were performed to count and characterize pollution microparticles, both on the abutment surface and implant–abutment connection. For the control and test groups, mean values and standard deviations were calculated for number and density of micro-particles. Statistical differences were determined by one-way ANOVA with Scheffe multiple comparison test. The level of statistical significance was set at P � 0.05. Additional microbiologic analysis was performed to detect bacterial contamination on the abutment surface. Results: In the control group, the number of micro-particles on average was 117.5, and 14.1, respectively, on the abutment surface and connection. In the test groups, no pollution was revealed on the abutment (average of 1.09 and 1.13 spots, respectively, in test group 1 and test group 2) and connection (1.28 and 1.41, respectively, in test group 1 and test group 2). The analysis of variance (ANOVA) showed a statistically significant difference for all the variables examined. For each variable, at least one of the groups differs from the others. Scheffe multiple comparison test showed that all comparisons for every variables between the control group and both groups are significant, while there were some comparisons between test group 1 and test group 2 that were not significant. EDAX microanalysis identified micro-particles as residual of lubricant mixed with traces of Titanium and other metals. Microbiologic analysis demonstrated the presence of bacterial growth on the abutment surface only in the control group (111.5 � 11.43 CFU/ml/implant–abutment as mean value). In the test groups, absence of growing microorganisms was found. Conclusions: This study confirmed that both plasma and ultrasonic treatments can be beneficially adopted for abutment cleaning process after laboratory technical stages, to supposedly favor soft tissue healing and implant–prosthetic connection stability.

Objectives: A randomized controlled trial was performed to assess soft tissue cell adhesion to implant titanium abutments subjected to different cleaning procedures and test if plasma cleaning can enhance cell adhesion at an early healing time. Study Design: Eighteen patients with osseointegrated and submerged implants were included. Before re-opening, 18 abutments were divided in 3 groups corresponding to different clinical conditions with different cleaning processes: no treatment (G1), laboratory customization and cleaning by steam (G2), cleaning by plasma of Argon (G3). Abutments were removed after 1 week and scanning electron microscopy was used to analyze cell adhesion to the abutment surface quantitatively (percentage of area occupied by cells) and qualitatively (aspect of adhered cells and presence of contaminants). Results: Mean percentages of area occupied by cells were 17.6 ± 22.7%, 16.5 ± 12.9% and 46.3 ± 27.9% for G1, G2 and G3 respectively. Differences were statistically significant between G1 and G3 (p=0.030), close to significance between G2 and G3 (p=0.056), and non-significant between G1 and G2 (p=0.530). The proportion of samples presenting adhered cells was homogeneous among the 3 groups (p-valor = 1.000). In all cases cells presented a flattened aspect; in 2 cases cells were less efficiently adhered and in 1 case cells presented filipodia. Three cases showed contamination with cocobacteria. Conclusions: Within the limits of the present study, plasma of Argon may enhance cell adhesion to titanium abutments, even at the early stage of soft tissue healing. Further studies with greater samples are necessary to confirm these findings. Key words:Connective tissue, dental abutments, randomized controlled trial, clinical research, glow discharged abutment, plasma cleaning.

This in vitro study analyzed the reverse torque (RevT) of abutment screws following different cleaning treatments. A convenience sample of 50 customized titanium abutment screw complexes was divided into five groups: cleaning by steam (control group), cleaning by Argon plasma (test groups 1 and 2 [with chlorhexidine gel]), and replacement of old screws with new ones (test groups 3 and 4 [with chlorhexidine gel]). Abutments were screwed onto implants and tested for RevT. The RevT of the test groups was significantly higher than that of the control group. No statistically significant difference between test groups was noted except between groups 2 and 3.

The appearance and long-term stability of peri-implant bone, mucosa, and gingiva determine the success of implant-supported prostheses from both the esthetic and functional standpoints. Any surgical or prosthetic technique that takes into consideration only some variables, or that only intervenes in a limited phase of treatment, is a potential source of a partially successful and/or unpredictable clinical outcome. This article describes the underlying principles and surgical-prosthetic procedures of a systematic regenerative approach, edentulous site enhancement (ESE). The goal of this approach is to improve the anatomy of edentulous sites. Applied to implant dentistry, this approach enables peri-implant tissue to be managed predictably, optimizing the functional and esthetic result of restorations with regard to treatment time, number of surgical stages, long-term prognosis, and incidence of complications. The principles underlying the ESE approach, which are independent of any specific implant system, are applicable in the majority of clinical situations, regardless of the esthetic requirements.

The successful esthetic integration of a prosthesis is dependent on the anatomic site in which the restoration is inserted. Edentulous site enhancement is a regenerative approach based on the following: (1) anatomic evidence that the morphology of soft tissues is dependent on the underlying support (bone, roots, implants) but also significantly influenced by overlying structures (fixed or removable prostheses); (2) histologic evidence of the remarkable regenerative capacity of the newly formed tissue that develops during healing by secondary intention; (3) clinical evidence that it is possible to guide the formation of this new regenerative tissue by creating a support with proper morphology and a highly polished surface; (4) observations that positive pressure exerted by alimentary bolus and negative pressure produced by deglutition affect the growth of this tissue healing by second intention; and (5) the application of appropriate oral hygiene techniques to guide tissue healing and maintain its integrity. The edentulous site enhancement approach is simple, practical, and predictable and offers minimal postoperative complications. This paper describes the edentulous site enhancement approach as applied in the pontic areas.

This article presents a regenerative technique, morphogenic bone splitting (MBS), which overcomes the limitations associated with expansion techniques described to date.The authors propose a method whereby the bone-mucosa-gingival complex (BMGC) is displaced in its entirety, establishing a new focus for a secondary hinge located in the coronal reaches of the osteotomy. Depending on clinical needs, this approach modifies or eliminates the facially inclined hinge displacement characteristic of ridge expansion techniques. By exploiting the inherent capacity for second intention healing, the regenerative MBS technique avoids the use of graft material, membranes, or mechanical devices. It effectively harnesses the intrinsic regenerative capabilities of the treated site.The MBS technique is performed in a single operation. By permitting the insertion of implants of an appropriate size in the optimum position for esthetic and functional requirements, it achieves the desired 3-dimensional reshaping of the BMGC and thereby restores the anatomy of the implant site. This reshaping includes: root prominences, keratinized gingiva, papillae, fornix, and the mucogingival junction. In addition to these esthetically significant issues, it permits implants to be placed at a functionally favorable axial inclination.