The International Journal of Oral & Maxillofacial Implants, Supplement/2016

Purpose: Starting in 2012, the Academy of Osseointegration initiated the planning process for an AO Summit to develop clinical practice guidelines (CPGs) for management of the edentulous maxilla. Materials and Methods: A planning committee led by Professor Clark Stanford and Dr Ole Jensen created a work plan based on five domain areas to be addressed by the summit. The five domain areas were defined as: (1) role of grafting for ridge development for implant placement, (2) role of implant design and systems in management of the edentulous maxilla, (3) role of imaging to guide implant placement, (4) role of biologics to assist in ridge development, and (5) role of prosthetic management. Results: The summit was held in August 2014, and the results are presented in this overview. All of the supporting systematic reviews and the detailed CPGs are presented in this special edition of JOMI. Conclusion: While the evidence was observed to be weak in regard to the literature for most of the systematic reviews, the summit strived to establish the current best evidence and practical CPGs that will assist clinicians in practice. Keywords: consensus conference, edentulous maxilla, clinical practice guidelines

Purpose: Multiple bone augmentation techniques are available to allow implant placement in the atrophic maxilla. However, questions remain, regarding which methods are most predictable and have the best dental implant survival rate (SR) in grafted bone. The aim of this systematic review was to evaluate literature from the last 30 years to determine predictability of bone grafting of the edentulous maxilla for implant placement as well as for implant SR. Materials and Methods: A systematic review was performed of studies conducted during the period 1980 to 2014, specifically focusing on the edentulous maxilla and bone grafting. Surgical techniques discussed in the publications included were guided bone regeneration (GBR), sinus augmentation, onlay bone grafting, nasal floor grafting, and Le Fort I interpositional grafting. All identified articles were evaluated and screened to meet strict inclusion criteria of at least 10 patients, complete maxillary edentulism, 1-year follow-up, and information regarding implant SR. A total of 974 articles were identified with electronic and manual searches. On further evaluation of the titles and abstracts, 44 articles were excluded. Full texts of the articles that met the inclusion criteria were reviewed, of which 40 articles were included in the systematic review. Results: For onlay bone grafting, 16 studies were included and analyzed, and the weighted mean implant SR was 85.2%. For the GBR technique, two studies were included, with a reported SR ranging from 96.1% to 100%. For Le Fort I interpositional grafting, 11 studies were included, with a weighted mean SR of 89.6%. For the sinus augmentation technique, 12 studies were investigated and the weighted mean SR was 91.5%. For the combination technique, six studies were analyzed and the weighted mean SR was 93.6%. Conclusions: All five treatment modalities discussed-onlay bone grafting, GBR, Le Fort I interpositional grafting, maxillary sinus augmentation, and/or nasal floor inlay grafting or the combination approach-can be successfully used to augment edentulous maxillary ridge with high implant SRs. Keywords: bone augmentation, GBR, Le Fort I interpositional grafting, nasal floor grafting, onlay bone grafting, sinus augmentation

Purpose: To identify and critically appraise scientific publications evaluating the possible effect of implant design on treatment outcomes in the rehabilitation of patients with a fully edentulous maxilla. Materials and Methods: Scientific reports were sought in three electronic bibliographic databases, combined with searches for meeting abstracts, and in the grey literature. English, German, or Scandinavian scientific publications on prospective or retrospective longitudinal studies with effects of an implant design or feature on the treatment outcomes were eligible. Minimum requirement for inclusion was at least 10 study participants who were followed up for at least 2 years after implant loading. The PRISMA guidelines were followed for selecting data to extract from the individual studies. These were characteristics of the individual studies, risk of bias within individual studies, and the results of individual studies. Three editorial teams independently identified and extracted the data. Results: The search resulted in 998 primary studies, of which 525 met the inclusion criteria and were read in full text. Of these, 105 studies were included in qualitative syntheses. Seventeen studies were designed with an objective to assess effects of implant design or feature on outcomes, 23 studies described tilted implants to enable placement of longer implants, 30 studies reported effects of implants placed in zygomatic bone with or without additional alveolar implants, and 9 studies reported effects of implants placed in pterygoid bone or other bony buttresses with or without additional alveolar implants. Sixteen articles reported bone augmentation with simultaneous or delayed implant placement in patients with a predominantly Cawood-Howell bone class V and VI maxilla. Ten papers reported effects of implant design on outcomes, despite the lack of an a priori stated objective to assess a particular implant design or feature. There is a lack of compelling data to state that one particular implant system or design feature stands out amidst others, when applied to restoring the fully edentulous maxilla with implant-retained prostheses. Conclusion: This systematic review failed to identify compelling evidence to conclude that any particular implant or feature affects the treatment outcome in patients with a fully edentulous maxilla. Keywords: bibliographic, databases, humans, prospective studies, retrospective studies, treatment outcome, zygoma

Purpose: This systematic review verified the usefulness/limitations of static surgical guides during implant surgery in the edentulous maxilla. The PICO question was: "Does the use of digitally generated surgical guides vs conventional techniques affect the following outcomes: surgical complications, implant complications, prosthesis complications, implant survival, prosthesis survival, economics, patient satisfaction, and maintenance intervention?" Materials and Methods: The electronic searches retrieved 2,588 unique articles from which eventually 36 full-text articles were read for eligibility. Because no randomized controlled clinical trials could be found, the PICO question had to be reformulated, now only looking to the outcome of digitally generated surgical guides without comparison with conventional techniques. Results: Although long-term data are lacking, the outcome of implants placed with a static guide and of the prosthetic reconstruction seems similar to that expected from conventional techniques. The number of surgical complications with guided surgery is negligible. Guided flapless implant surgery offers slightly more comfort for the patient; however, the economic benefits are unclear. Conclusion: Implant therapy via static surgical guides in the maxilla is predictable, with slightly more comfort for the patient but with only minor economic advantages. Keywords: edentulous maxilla, guided surgery, computer planning, dental implant

Purpose: The aim of this systematic review was to evaluate current and emerging regenerative approaches for implant site development in the edentulous atrophic maxilla using tissue engineering and regenerative medicine (TERM) principles and to identify priorities for future research. Materials and Methods: Two independent examiners conducted a comprehensive search using specific keywords to identify original clinical studies using TERM for implant site development in the edentulous atrophic maxilla including indications for alveolar ridge preservation, horizontal alveolar augmentation, maxillary sinus augmentation, and augmentation of severe vertical or combined defects. Endpoints included clinical, radiographic, histologic, and patient-centered outcomes. Results: The initial search identified 3,061 articles. The final selection included 89 articles, of which 12 evaluated alveolar ridge preservation, 6 horizontal defects, 61 maxillary sinus augmentation, and 11 management of severe vertical or combined defects. A summary of the main findings relative to the effect of TERM-based approaches applied for implant site development in the atrophic maxillary segments is presented. Marked heterogeneity among included studies prevented meaningful quantitative analysis. The following relevant effects of TERM-based therapies for site development in the edentulous atrophic maxilla were observed: (1) recombinant human bone morphogenetic protein-2 in an absorbable collagen sponge carrier increased bone augmentation; (2) recombinant human platelet-derived growth factor BB in combination with freeze-dried bone allograft or beta tricalcium phosphate accelerated bone formation through accelerated remodeling of carrier biomaterials; (3) autologous cell therapy enhanced clinical and radiographic outcomes; (4) autologous cell therapy in alveolar ridge preservation provided superior histomorphometric outcomes (vital bone formation) at 6 weeks; and (5) platelet-rich plasma formulations combined with autologous bone grafts for maxillary sinus augmentation increased radiographic density and accelerated bone mineralization at 6 months. Conclusion: Clinical success has been demonstrated with the application of different TERM modalities for implant site development in the edentulous atrophic maxilla. However, indications are narrow and further study is needed. Clinical trials assessing meaningful outcomes, involving larger populations, and with longer follow-up are warranted to discern the effectiveness of the achieved results compared with a valid control. Keywords: atrophic maxillae, biological agents, cell- and tissue-based therapy, dental implants, implant-supported dental prosthesis, tissue engineering

Purpose: The aim of this systematic review is to report on the current knowledge regarding patient satisfaction as a primary outcome for maxillary complete denture therapy. We asked, "For the maxillary edentulous patient treated using maxillary dentures, what are the patient-based outcomes regarding quality of life and treatment satisfaction." Materials and Methods: An electronic search of publications up to March 2014 was established using four databases: PubMed, Web of Science, Scopus, and Embase. To meet the ultimate goal of establishing clinical guidelines based on available information, prospective comparative studies, cohort prospective studies, and retrospective studies on more than 10 subjects were included. The electronic search identified 4,530 articles that were evaluated at the title, abstract, and article level to include 31 articles of interest. The patient-based outcomes and satisfaction data included were examined and reported. Results: The studies included 5,485 participants. Of these, 2,685 were identified as wearing maxillary complete dentures. Reported mean ages ranged from 59.7 to 73.6 years. A systematic review indicated that the provision of new maxillary complete dentures for edentulous patients results in improved self-reported satisfaction and oral health-related quality of life. The included reports, while providing evidence that complete denture satisfaction of participants and new dentures improve self-reported outcomes, did not include variables that influence these positive outcomes. Conclusion: A broad range of evidence supports the use of complete dentures for rehabilitation of the edentulous maxilla. When considering treatment of the edentulous maxilla, the expectations of patients for esthetic and phonetic (social) rehabilitation are high and can be met using maxillary complete dentures as the mode of prosthetic rehabilitation. Patients dissatisfied with new complete dentures may be referred for dental implant therapies involving fixed or removable prostheses. Keywords: complete dentures, edentulism, edentulous maxilla, esthetic satisfaction, implant overdenture, implant-supported fixed prosthesis, OHIP-EDENT, OHQoL

Purpose: To evaluate patient-related outcomes in restoring the edentulous maxilla with an implant overdenture. Materials and Methods: A comprehensive systematic review of the literature was conducted. Publications reporting patient-based outcomes with concomitant data on implant and/or prosthetic success were selected using predetermined inclusion criteria that were agreed upon by the two reviewers. Results: Twenty-three publications related to 20 study cohorts were identified to meet the inclusion criteria for maxillary implant overdentures: two randomized controlled trials (RCTs), 13 prospective case series including two crossover trials, and five retrospective studies. Conclusion: An implant overdenture offers a stabilized removable solution for the edentulous maxilla, which provides increased patient satisfaction and quality of life improvement. A palateless design supported by four to six implants with a wide anteroposterior span has been successfully applied in some investigations. A higher failure rate was experienced with machined implants, particularly with short implants (length 10 mm). Although both splinted and solitary anchorage systems are advocated, maintenance is higher for solitary attachments and inflammation is increased beneath the bars. Long-term maintenance care is essential for all designs. Well-designed RCTs with larger sample cohorts with longer follow-up periods are required to amplify patient- and clinician-based outcomes. Keywords: implant/prosthetic survival/success, maintenance, maxillary implant overdentures, patient satisfaction

Purpose: This review was conducted to provide information to support the establishment of clinical guidelines for the treatment of maxillary edentulism using implant-supported fixed dental prostheses. Materials and Methods: Initial efforts were directed toward a systematic review with a defined PICO question: "For maxillary edentulous patients with dental implants treated using a fixed prosthesis, what is the impact of prosthesis design on prosthesis survival and complications?" Following a title search of more than 3,000 titles identified by electronic search of PubMed, 180 articles were identified that addressed the clinical evaluation of maxillary dental implant prostheses. The broad methodologic heterogeneity and clinical variation among reports precluded this approach for a systematic review. The information was extracted using a standardized extraction table by two pairs of investigators, and the reported outcomes were then summarized according to reported outcomes for implant prostheses supported by four, six, or eight implants using unitary or segmented prostheses. Results: This review indicated that high prosthetic survival is observed using all approaches. The advantages of using fewer implants and a unitary prosthesis are revealed in the surgical phases, and complications commonly involve the fracture or detachment of acrylic teeth and reduced access for proper oral hygiene and related biologic complications. Using six implants typically involved grafting of posterior regions with advantages of reduced cantilevers and redundancy of implant support. Reduced prosthesis survival in these cases was associated with poor implant distribution. Segmented prostheses supported by six or more implants offered greater prosthetic survival, perhaps due to posterior implant placement. Advantages of a segmented prosthesis included pragmatic issues of accommodating divergent implants, attaining passive fit, combining prosthetic materials, and relative simplicity of repair. Conclusion: The existing literature demonstrated that maxillary edentulism may be treated successfully using alternative approaches involving four, six, or more implants. The procedural diagnostics, treatment, and maintenance for these different approaches all require advanced knowledge and careful communication among the therapeutic team. The prosthetic therapeutic success requires maintenance, repair, and possible multiple replacements within the patient's lifetime.