Immediate implant placement in molar extraction sites:a 1-year prospective case series pilot study

Background There is a growing tendency to place single tooth implants immediately after extracting a failing tooth in the posterior region. The aim of this prospective case series pilot study was to evaluate immediate implant placement in molar post-extraction sites during a 1-year follow-up period. Materials and methods Fifteen consecutive patients with a single failing molar in the maxilla or mandible, and presenting enough bone to expect primary implant stability and an implant site free of infection, were included. The implants, with a large thread depth and sharp thread edges, were placed in each patient according to a two-staged surgical procedure. Three months later, a full contour screw-retained zirconia restoration with an angulated screw channel abutment was provided. Clinical and radiographic examinations were performed 1 month and 12 months after placing the restoration. In addition, the patients' satisfaction with the restoration was scored after 12 months. Results Four out of 15 of the mobile implants had to be removed before the 1-year evaluation. The implant and restoration survival rates were 73.3% at the 1-year evaluation (n = 15). The mean marginal bone loss, from loading to the 12-month follow-up, was 0.17 mm (n = 11). The mean plaque, calculus, peri-implant mucosa, bleeding, and pocket probing depth scores were low, depicting healthy peri-implant conditions. The patients were very satisfied. Conclusion It was demonstrated, within the limitations of this study, that immediate placement of regular diameter implants in molar post-extraction sites in the maxilla and mandible resulted in a high implant failure rate during a 1-year follow-up period

A new index for rating aesthetics of implant-supported single crowns and adjacent soft tissues - the Implant Crown Aesthetic Index:A pilot study on validation of a new index

Objectives: The important item of aesthetics is rarely included in evaluation studies. The aim of this study was to develop and validate an index for rating aesthetics of implant-supported single crowns and adjacent soft tissues. Material and methods: Nine items were selected, which have an influence on the aesthetic result. The items are based on the anatomic form, colour and surface characteristics of the crown and on the anatomic form, colour and surface characteristics of the peri-implant soft tissues. Two oral-maxillofacial surgeons and two prosthodontists rated 24 implant-supported single-tooth restorations and adjacent soft tissues on a form with the nine items of the rating index. The rating was carried out twice by each of the examiners. Weighted Cohen's kappa was calculated to express the intra- and interobserver agreement. Results: Intraobserver results indicated that the agreement between the first and second rating of both the prosthodontists was good (both 0.7) and that the agreement of the oral-maxillofacial surgeons was moderate (0.49 and 0.56). The best interobserver agreement was found between the two prosthodontists (0.61, good agreement). Conclusions: The Implant Crown Aesthetic Index is an objective tool in rating aesthetics of implant-supported single crowns and adjacent soft tissues. The rating is best be carried out by one prosthodontist to have the highest reliability

Dental implant treatment for two adjacent missing teeth in the maxillary aesthetic zone:a comparative pilot study and test of principle

Aim The aim of this prospective comparative pilot study was to evaluate hard and soft peri-implant tissues in patients with a missing adjacent central and lateral upper incisor treated with either one implant and an implant crown with a cantilever or two implants with solitary implant crowns up to 1 year after functional loading. Material and methods In the "Implant-cantilever group", five patients were treated with one dental implant in the region of the central incisor (NobelReplace Groovy Regular Platform). In the "Implant-implant group", five patients were treated with two adjacent dental implants: at the position of the central incisor (NobelReplace Groovy Regular Platform) and at the position of the lateral incisor (NobelReplace Groovy Narrow Platform). Implant survival, pocket probing depth, papilla index, marginal bone level and patient satisfaction were assessed during a 1-year follow-up period. Results No implants were lost during the 1-year follow-up. Mean pocket probing values of the implants were comparable between the two groups. Papilla index scores in both groups were relatively low, pointing towards a compromised papilla. Marginal bone loss was minimal and comparable between the groups. Patient satisfaction was very high in both groups. Conclusion In this 1-year prospective comparative study, no large differences in hard- and soft-tissue levels could be shown between patients with a missing central and lateral upper incisor treated with either one implant and an implant crown with a cantilever or two implants with solitary implant crowns. To cite this article:Tymstra N, Raghoebar GM, Vissink A, Meijer HJA. Dental implant treatment for two adjacent missing teeth in the maxillary aesthetic zone: a comparative pilot study and test of principle.Clin. Oral Impl. Res. 22, 2011; 207-213.doi: 10.1111/j.1600-0501.2010.02017.x

Digital Workflow for Immediate Implant Placement and Chairside Provisionalization in the Esthetic Zone

Introduction: Immediate implant placement and immediate chairside provisionalization in the esthetic zone require meticulous treatment planning. A digital workflow that combines intraoral scans and a cone beam computed tomography scan can be used to visualize the surgical and restorative aspects of the treatment and to plan a prosthetically driven implant position. A digital workflow in implant dentistry enables the prefabrication of an individualized CAD/CAM temporary restoration, based on the planned implant position. This could be a predictable method to deliver a screw-retained temporary restoration, directly after static computer-assisted immediate implant surgery. Interventions. Three patients with a failing tooth in the maxillary esthetic zone were treated with immediate implant placement and chairside provisionalization using this digital workflow. After 3 months, a final restoration was placed. Clinical, radiographic, and patient-reported outcome measures were collected prior to implant treatment, 6 weeks after placing the temporary restoration and then 1 month and 1 year after placing the final restoration. Outcomes. At the 1-year follow-up, healthy soft tissues were observed, and peri-implant bone levels were stable. Patient satisfaction after the treatment was high. Conclusion: The three reported cases demonstrate the potential for predictable immediate implant placement and chairside provisionalization using a digital workflow

Short dental implants in the posterior region : the effect of platform-switching and a nanorough surface on peri-implant bone loss

Korte implantaten (<10 mm lengte) worden steeds vaker gebruikt ten behoeve van het prothetisch herstel van verloren gegane kiezen in de boven- en/of onderkaak van patiënten die voor de rest nog alle tanden en kiezen hebben (partieel dentate patiënten). In het verleden werden korte implantaten geassocieerd met meer implantaatverlies in vergelijking tot langere implantaten (>10 mm lengte), waarvoor meerdere redenen bestaan. In de eerste plaats heeft een kort implantaat minder oppervlak beschikbaar voor contact tussen bot en implantaat dan een langer implantaat met eenzelfde diameter. Ten tweede worden korte implantaten voornamelijk geplaatst in de zijdelingse delen van de boven- en onderkaak, waar, zeker in de bovenkaak, de botkwaliteit beduidend slechter is dan in de frontregio. In de derde plaats wordt, wanneer de kaak in hoogte is geslonken (resorptie), vaak een zeer grote kroon vervaardigd op een relatief kort implantaat om het kauwvlak te bereiken, wat tot een grotere kroon-implantaatratio leidt (d.w.z. dat de lengte van de kroon erg groot wordt t.o.v. de lengte van het implantaat). Bij natuurlijke elementen wordt een relatief grote kroon-wortelratio als een ongunstige belasting beschouwd voor het element. Om het gebruik van korte implantaten te vermijden, kan het kaakbot worden opgebouwd met een bottransplantaat voordat het implantaat wordt geplaatst. Deze aanpassing in de anatomie van de patiënt maakt het mogelijk een langer implantaat te plaatsen. Maar deze extra chirurgische behandeling leidt tevens tot een grotere morbiditeit, hogere kosten en een langere behandelperiode. Aangetekend moet worden dat in de literatuur geen consensus bestaat betreffende de definitie van een kort implantaat. In dit proefschrift wordt een implantaat met een lengte van minder dan 10 mm als een kort implantaat beschouwd. Een belangrijke factor voor het welslagen van een behandeling met korte implantaten is het minimaliseren van peri-implantair botverlies, wat dikwijls als gevolg van botresorptie optreedt, rond de hals van het implantaat (marginaal botverlies). Om minder marginaal botverlies en hogere slagingspercentages te realiseren is enige tijd geleden het zogenaamde platform-switching concept (het plaatsen van een opbouw (abutment) met een diameter kleiner dan die van het implantaat) geïntroduceerd. Daarnaast is een nieuw implantaatoppervlak op de markt gekomen, waarbij op nanoniveau middels depositie van calciumfosfaat (CaP) op het implantaatoppervlak is getracht een verfijnde oppervlakteruwheid te bereiken. Het was echter niet bekend of bij de toepassing van korte implantaten platform switching en het nanoruwe implantaatoppervlak zouden resulteren in minder resorptie van marginaal bot, in een hogere implantaatoverleving, en in, op histologisch niveau, meer bot-implantaatcontact. Nowadays, short (<10 mm in length) implants are increasingly used for the prosthodontic rehabilitation of the partially edentulous posterior mandible or maxilla. Short implants have been associated with lower survival rates when compared to longer implants, for which are several presumed reasons. First, compared to longer implants with a comparable diameter, the available area for bone to implant contact is less when short implants are used. Secondly, in partially edentulous patients short implants are mostly placed in the posterior zone where the quality of the alveolar bone is poorer than in the anterior zone, especially in the maxilla. Thirdly, often a very outsized crown has to be made to reach occlusion, because of the extensive resorption in the posterior region, which results in a higher crown to implant ratio. To avoid the use of short implants, the alveolar bone can be augmented before implant placement using a grafting technique. This modification in the patient’s anatomy makes it possible to insert a longer implant, but an extra surgical intervention also leads to greater patient’s morbidity, higher costs and a longer treatment period. There is no consensus in the literature on the definition of a short implant, however. Several authors have reviewed the literature of applying short implants in the prosthodontic rehabilitation of (partial) edentulous patients. Reviewers concluded that important confounders (e.g., length, surface topography, smoking, implant location (mandible vs. maxilla), bone augmentation procedure) needed to be addressed in future studies, as they might be a key factor for the success in the use of short implants. No systematic review with meta-analyses to determine the role of these possible predictors was yet performed on short implants in the partially edentulous patients. Furthermore, to aim for less marginal bone resorption and even higher implant survival rates, the search for refining implant design and surface topography is continuing. This search has included the rather recent introduction of the concept of platform switching (placing a smaller-diameter abutment on a wider-diameter implant) and a changed surface topography and chemistry of the implant (nanometer-sized irregularities and deposits of calcium phosphate (CaP) on the implant surface). It is unknown, however, whether platform switching and the changed surface and chemistry of the implant resulted in higher bone to implant contact, higher implant survival rates and less resorption of marginal bone around implants, at least with regard to short implants. Therefore, the general aim of the in this thesis described PhD research was to analyse short implants placed in the resorbed posterior region of partially dentate patients with regard to marginal bone resorption, survival rate, clinical performance and patient’s satisfaction.

Inter- and intraobserver reproducibility of buccal bone measurements at dental implants with cone beam computed tomography in the esthetic region

BACKGROUND: Sufficient buccal bone is important for optimal esthetic results of implant treatment in the anterior region. It can be measured with cone beam computed tomography (CBCT), but background scattering and problems with standardization of the measurements are encountered. The aim was to develop a method for reliable, reproducible measurements on CBCTs. METHODS: Using a new method, buccal bone thickness was measured on ten CBCTs at six positions along the implant axis. Inter- and intraobserver reproducibility was assessed by repeated measurements by two examiners. RESULTS: Mean buccal bone thickness measured by observers 1 and 2 was 2.42 mm (sd: 0.50) and 2.41 mm (sd: 0.47), respectively. Interobserver intraclass correlation coefficient was 0.96 (95% CI 0.93 to 0.98). The mean buccal bone thickness of the first measurement and the second measurement of observer 1 was 2.42 mm (sd: 0.50) and 2.53 mm (sd: 0.49), respectively, with an intraobserver intraclass correlation coefficient of 0.93 (95% CI 0.88 to 0.96). The mean buccal bone thickness of the first measurement and the second measurement of observer 2 was 2.41 mm (sd: 0.47) and 2.52 mm (sd: 0.47), respectively, with an intraobserver intraclass correlation coefficient of 0.96 (95% CI 0.93 to 0.97). CONCLUSIONS: Applying the methods used in this study, CBCTs are suitable for reliable and reproducible measurements of buccal bone thickness at implants

Immediate Placement and Restoration of a New Tapered Implant System in the Aesthetic Region:A Report of Three Cases

Objective: To assess the clinical, radiographic, aesthetic, and patient-centred outcomes of a new implant system applied for an immediate implant placement and restoration approach in single tooth replacement of anterior maxillary teeth. Material and Method. Three cases were treated with a bone level tapered implant. All patients were treated with the same strategy involving flapless extraction and implant placement with simultaneous augmentation. Implants were provisionally restored with a screw-retained restoration at the day of surgery. Definitive restoration was fabricated after 3 months. Follow-up was one year after definitive restoration. Results: At the 1-year follow-up, the implants were stable and no complications had occurred. Peri-implant bone levels had increased with a mean value of 0.24 ± 0.30 mm between definitive restoration placement and 1 year of follow-up. Clinical outcome scores showed healthy soft tissues. Mean Pink and White Esthetic scores were rated 7.0 and 7.3, respectively. Mean patient satisfaction had improved from 55.7 (pretreatment) to 90.0 (1-year follow-up) on a 0-100 VAS scale. Conclusion: Immediate implant placement and restoration with the new tapered bone level implant system are accompanied by good initial clinical and radiographic results as well as high patient satisfaction

Early loading of endosseous implants in the augmented maxilla:A 1-year prospective study

In 10 patients, 68 endosseous implants were inserted in the augmented edentulous maxilla using a one-stage implant placement technique. Three months before implant insertion, the width and height of the alveolar crest were augmented with autologous bone grafts from the iliac crest. In all cases, the resulting bone volume was sufficient for implant insertion. According to an early loading protocol, the implant-supported overdenture was fabricated 2 months after insertion of the implants. Evaluation was performed according to a standardised protocol immediately and 1 year after fabrication of the prosthetic construction. The protocol included assessment of both clinical (bleeding score, pocket depth, implant mobility) and radiographic (marginal bone level on standardised radiographs) parameters. Three implants in two patients in the upper jaw were lost (survival rate: 95.6%). The peri-implant tissues had a healthy appearance and bone loss was minimal. Overall, the patients were very satisfied with the prosthetic construction. From this preliminary study, it is concluded that in selected cases, early loading of implants may develop into a predictable treatment modality after augmentation of the maxilla