Background: The long-term success of an implant depends on the stability of bone support for the implant. Most crestal bone loss occurs in the first year of implant placement. Platform switching is an approach which can be clinically applied to preserve the crestal bone. Purpose: The purpose of this review is to discuss the literature dealing with the platform switching concept to preserve the crestal bone, the mechanism by which it contributes to maintenance of marginal bone, its clinical applications, advantages and disadvantages, in order to assess its survival rates. Materials and Methods: PubMed and Google Scholar were used to find studies involving platform switching concept from 2005 up to October 2009. Results: Literature search revealed studies involving concepts of platform switching, comparison of platform-switched and non-platform-switched implants, case reports on platform switching and studies with histological and finite element analyses regarding platform switching. Conclusion: Platform switching helps preserve crestal bone around the implants and this concept should be followed when clinical situations in implant placement permit.

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Spark erosion is a metal removal process using electric current under carefully controlled conditions. It is used for precise and accurate fabrication in the field of fixed, removable and implant prostheses. The scope of this article is to discuss the mechanism of action of the process and its significance in implant dentistry along with critical evaluation of its merits and demerits.

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This article is a case report of removal of a dental implant using electrosurgery. A discussion will outline a possibly less invasive method to remove the dental implant. This involves the use of electrosurgery unit to cause a thermo-necrosis of the bone and therefore a weakening of the bone-implant interface. It is suggested that a controlled laboratory experiment be carried out to look at the effects of mono-polar electrosurgery on osseointergration on dental implants and the possible use of this method to allow for simple removal of poorly positioned fixtures and also fixtures with significant bone loss but no mobility.

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Background: The primary etiologic factor for peri-implant infections is the adhesion of biofilms on oral implant surfaces in the area of soft-tissue penetration. The aim of the present study was to examine in situ biofilm growth directly on implant-abutment surfaces without the use of oral splints and to determine the effect of intraoral abutment localization on biofilm growth. Materials and Methods: Fifteen titanium healing abutments were inserted in six patients for 14 days. The newly formed supragingival biofilm on the titanium surface of the healing abutments was stained with fluorescent Live/Dead Baclight kit before examination by confocal laser scanning microscopy. The biofilm was scanned in terms of its surface coverage and thickness and different sites. Results: The results show that the biofilm has a different structure in every patient, with the thickness of the biofilm structure ranging between 0 and 80 ΅m and the surface coverage between 0 and 97% of the abutment surface. There was similar biofilm surface coverage at different intraoral locations, whereas the biofilm was significantly thicker in the mandible as compared to maxillary implant abutments. Conclusion: The method uniquely describes an effective way to depict biofilm development on implant surfaces in the supra- and sub-gingival regions.

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Background: The evolution in implant procedures has helped decrease loading times. Procedures can be optimized in post-extraction implantation with immediate loading. With a decrease in periodical needs for oral rehabilitation, the biological impact and psychological integration may be improved. This study aims to compare immediate versus delayed loading in post-extraction implantation. Materials and Methods: In a private practice of two practitioners, 170 Straumann post-extraction implants (107 immediate and 63 delayed loading) were tracked during a 7-year period. Results: According to Misch criteria, no difference in success rates was found between immediate (96.4%) and delayed (96.8%) loading in post-extraction implants. Conclusion: This retrospective study showed that a post-extraction procedure does not compromise immediate loading success in the short and medium term. Complementary prospective and randomized studies are necessary to validate these results.

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Restoring the edentulous patient with an esthetic and functional reconstruction may present numerous challenges to the clinician. The patient's occlusal vertical dimension, centric relation, esthetics and phonetics need to be determined and maintained throughout the restorative process. This clinical report describes the fabrication of implant supported fixed prosthesis and implant-tissue supported overdenture with low-profile attachments and its step-by-step approach to provide an esthetic result for a patient with limited inter-arch space.

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An atrophied posterior maxilla is the most challenging intraoral area confronting the implantologists, requiring utmost skill for the achievement of successful results. This case report exemplifies the use of a lateral wall osteotomy approach for sinus floor elevation, combined with the composite grafting to provide the ideal milieu for placement of a dental implant.

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Aim: The purpose of this study is to determine the survival rate of dental implants placed immediately into fresh extraction sockets in the maxillary anterior region by clinically evaluating the peri-implant soft tissue health and by radiographically evaluating the bone height mesial and distal to the implants. Materials and Methods: Patients with maxillary anterior teeth indicated for extraction were selected. Indicated teeth were extracted, sockets were prepared and implants were placed into prepared sockets. After the integration period, prostheses were cemented. Patients were reviewed at three-month intervals after prosthesis placement for a period of one year with evaluation of all clinical and radiographic parameters. Results: Causes for extraction of teeth were root fractures, endodontic failures, internal resorption, external resorption, teeth with open apex and over-retained deciduous teeth. The mean plaque index and gingival index showed a decrease in values during the follow-up period. All implants were immobile. Radiographic analysis using Image J software (of the peri-apical radiographs) showed significant bone remodeling around the neck of the implants. Immediate implant survival rate was 100% during one-year follow-up. Conclusion: Thus, with regard to implant survival, there seems to be no reason to refrain from placement of implants into extraction sockets in the maxillary anterior region when the sites are carefully selected.

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The control of anchorage is one of the most crucial factor in orthodontic treatment planning. Traditionally, headgears have been used to be one of the most efficient means to gain anchorage but they have their own limitations and so these methods are limited in delivering results, which commensurate with our idealistic goals. Recently, a number of case reports have appeared in the orthodontic literature documenting the possibility of overcoming anchorage limitations via the use of temporary anchorage devices-biocompatible devices fixed to bone for the purpose of moving teeth. Although skeletal anchorage is here to stay in orthodontics, there are still many unanswered questions. So the purpose of this article is to provide an overview of the current status of orthodontic implants and a discussion of established techniques.

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Objectives: To study the efficacy of pre-evaluation of implant sites by Dentascans. Materials and Methods: Twenty five patients between age groups of 15 -and 80 years requiring implant placement were selected for this study. The computed tomography (CT) scan machine used for this study was Siemens Somatom Sensation 64. This has multidetector technology with 32 detector array and 64 data channels. Dental software used was Syngo Dental CT 2006 A-W VB20B-W. Axial, paraxial and panoramic images obtained were evaluated for available ridge height and width at implant sites, proximity to maxillary sinus and inferior alveolar canal, easy identification of inferior alveolar canal, radiographic presence of bony concavities and density at implant sites. Results: Dentascan was an effective software in pre-evaluation of available height and width at the implant sites. There was a co-relation between the available bone at the implant sites and region of jaw, sex and age of patients. Proximity to maxillary sinus and inferior alveolar canal was clearly demonstrated by Dentascans. Inferior alveolar canal was identified in 85.71% cases. Bony concavities were identified in 22.95% cases. Dentascans provide subjective evaluation of bone density in Hounsfield units (symbol HU). Conclusion: Dentascans are a rapid, time saving, effective, safe and indispensable procedure in dental implantology. Dentascans determines the available bone at the implant sites accurately without any magnification or distortion that is observed in panoramic radiography. Osseous morphology variations like knife edge ridges, which cannot be demonstrated on conventional radiography, could be appreciated on Dentascans. Bony concavities may not be observed on panoramic radiography; Dentascans provide the opportunity to appreciate such details. Critical anatomical landmarks can be clearly demonstrated on Dentascans. Dentascans provide a subjective evaluation of the density at the implant site.

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The purpose of this study is to determine the predominant periodontopathogenic microbiota in peri-implant sulcus of osseointegrated implant of a healthy patient. A healthy patient with good periodontal condition was selected for AQB single-piece implant placement. Periodontal pathogens were checked in patient's saliva prior to implantation. F. nucleatum (0.25%) and B. forsythensis (0.01%) were detected. An HA-coated one-stage implant (AQB) was implanted in the missing lower second molar region. Then samples were collected from the peri-implant sulcus using paper point, every month for eight months after the implantation and fixation of porcelain crown. RT-PCR (invader method) was used to detect the periodontal pathogens. No periodontal pathogens were observed up to three months. F. nucleatum (0.16 %) was detected at three months, T. forsythensis (0.06%) and F. nucleatum (0.06%) were detected after four months. A. actinomycetemcomitans (0.054%) and F. nucleatum (3.29%), were detected at six months. F. nucleatum (5%), (1.58%) were detected at seventh and eighth month.

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Context : Recent studies observed contamination of the inner parts of dental implants through bacterial penetration along the implant-abutment interface that may cause malodor and inflammation of peri-implant tissues. Aims : Evaluate in vitro bacterial leakage along the implant-abutment interface, comparing three types of connections : EH, IH and MT. Materials and Methods : Under sterile conditions, a colony of E. coli was inoculated in the apical portion of abutment screws, which were fixed to implants with a torque of 20 Ncm. Samples with immediate external contamination were discarded, while remaining specimens were placed in test tubes containing TSB. The broths that showed turbidity within the seven-day study period were planted in Petri dishes with TSA, and incubated in a bacteriological stove at 37°C for 24 h. At the end of the evaluation period, all assemblies were separated, and the internal content was collected using absorbent paper cones and saline water, and again planted to assess bacterial viability. The samples that did not contain viable E. coli were dismissed from the final results. As a result, 38 samples with EH, 40 with IH and 41 with MT connections were evaluated. Statistical Analysis Used : Survival curves were analysed using the Kaplan-Meyer test and compared by log-rank statistics. Results : There were no differences between the EH (10.53%), IH (4.88%) and MT (7.50%) connections. Conclusions : Bacterial infiltration occurred similarly in all three types of connections between abutments and implants, despite the different configurations of the interface.

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Aim: The study evaluates the stress formed around an implant and a natural tooth under occlusal forces, on different tooth implant-supported fixed prosthesis (TIFP) designs in order to suggest a design, which transmits less stress to the bone. Materials and Methods: A distal extension situation was utilized in this study to evaluate stress distribution around a natural tooth and an implant in TIFP models with three connection designs (i.e., rigidly connected to an abutment tooth, connected to an abutment tooth with a nonrigid connector [NRC], and connected to an abutment implant with an NRC). The stress values of the three models loaded with vertical forces (300 N) were analyzed using three-dimensional finite element analysis. Results: The highest level of stress around the implant and natural tooth was noted on the TIFP models with the RC. On the other hand, NRCs incorporated into the prostheses reduced the stress in the bone around the implant and natural tooth. Conclusion: The present study recommends the use of NRCs on the implant abutment-supported site, if the tooth and implant abutment are to be used together as fixed prosthesis supports. The NRC placed on the implant abutment site reduces the stress around the implant and natural tooth in a fixed prosthesis supported by tooth and implant increasing the life span of both.

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Purpose: Aim of the present study was to present the results of a retrospective analysis of maxillary sinus augmentation procedures performed with platelet-rich plasma (PRP) with a mean follow-up of about 5 years. The analysis was focused on implant survival rates and on the dimensional stability of the subantral cavity filling. Materials and Methods: Between 2000 and 2006, 28 patients were recruited for a maxillary sinus augmentation procedure performed with PRP. Two patients did not answer to the calling for the examination at distance, so they were excluded from the sample. The study involved 26 patients, for a total amount of 33 sinus augmentations, with an average follow-up of 65 months. In 26 procedures the grafting material used was a mixture of autologous bone taken from the oral cavity, deproteinized bovine bone Bio-Oss^® in a relationship of 1:3 and PRP, while in seven cases, the combination of Bio-Oss and PRP. The dimensional stability of grafting material was investigated through X-ray measurements carried out during X-ray postexaminations. Results: After a mean follow-up time of about 5 years, the implant survival rate registered was 95.9%, while the radiographical variables used to assess the dimensional stability of grafts, showed a mean decrease respectively of 9.38% and 14.61%. Discussion: Very good long-term results were achieved using autologous bone+Bio-Oss+PRP and Bio-Oss+PRP as filling materials in the maxillary sinus augmentation. Dimensional stability of cavity filling seems to represent a very important factor for implant procedures success. It is difficult to estimate the influence of PRP on a long-term basis. Conclusion: The implant survival rate obtained in this study was similar to the expected rate on the areas not subject to bone graft. The method applied showed to be reliable for bone regeneration in subantral cavities, showing a very good dimensional stability and a slight reabsorption over the years.

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Resorption ridges often pose hindrance in oral implant placement. Inadequate width of ridge requires some more innovative techniques in placing implants. One of such techniques is ridge splitting technique, which helps expansion of narrow ridge with or without fracture of cortical plates. This technique has the advantage of immediate implant loading, in comparison with other ridge widening techniques. This article deals a case study using the ridge splitting technique with the conclusion of, it could be consider as novel technique for implant placement in narrow ridges.

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Aim: To investigate the effect of two different abutment types on stress distribution in the bone around an implant under two loading conditions, vertical load and combined load (vertical + angle of 45°). Materials and Methods: Implant of 4.2 × 12 mm ² was used. Two 2-piece implant systems, Internal Hex and External Hex implant-abutment complex were used. The implant-abutment complex was embedded in bone and subjected to static load of 100 N vertically and a combined load (vertical + 45° angulation). Finite Element modeling of bone implant and abutment was done using Ansys Classical 10.0 software. Results: In external hex system Von Mises stress was 0.784 MPa and 3.502 MPa for spongious bone and 8.60 MPa and 45.126 MPa for compact bone under vertical and combined loading conditions respectively. Internal hex implant system showed values of 0.922 MPa and 2.22 MPa for spongious bone and 6.798 MPa and 26.29 MPa for compact bone for vertical and combined loading conditions. Conclusion: Internal Hex Implant system generated the lowest maximum Von Mises stress for all loading conditions. The maximum Von Mises stress occurred in the region of the compact bone under all loading conditions irrespective of the type of abutment use. Significant reduction in Von Mises stress was observed at the boundary between compact and spongious bone because of relatively low elastic modulus of spongious bone.

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Generally implants are considered to restore the masticatory function, occlusion, and esthetics once the natural teeth have given up their job in the masticatory system. Today implants are considered for partially edentulous and completely edentulous situations, in order to give greater advantages and benefits over the removable prosthesis, for patients. According to the scientific literature review there is no conclusive option or parameters available on the subject of implant occlusion. Implant occlusion is the result of the surgical placement of implant and prosthetic designs, but this never happened to be a goal What type of occlusion is still an ambiguity, present whenever we are restoring cases with implants. This case report illuminates the fact that an implant can be used to correct the malocclusion associated with natural teeth, irrespective of whether or not scientific literature has cited what type of occlusion is planned on an implant prosthesis, in cases where multiple implants are used and complex procedures are undergone. However, this case report stands as a witness to the fact that an implant can change the occlusion / correct occlusion.

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