An Osteotomy Tool That Preserves Bone Viability: Evaluation in Preclinical and Clinical Settings.

The main objectives of this work were to assess the efficiency, ease-of-use, and general performance of a novel osseoshaping tool based on first-user clinical experiences and to compare these observations with preclinical data generated in rodents using a miniaturized version of the instrument. All patients selected for the surgery presented challenging clinical conditions in terms of the quality and/or quantity of the available bone. The presented data were collected during the implant placement of 15 implants in 7 patients, and included implant recipient site (bone quality and quantity) and ridge evaluation, intra-operative handling of the novel instrument, and the evaluation of subsequent implant insertion. The instrument was easy to handle and was applied without any complications during the surgical procedure. Its use obviated the need for multiple drills and enabled adequate insertion torque in all cases. This biologically driven innovation in implant site preparation shows improvements in preserving vital anatomical and cellular structures as well as simplifying the surgical protocol with excellent ease-of-use and handling properties.

A Novel Osteotomy Preparation Technique to Preserve Implant Site Viability and Enhance Osteogenesis.

The preservation of bone viability at an osteotomy site is a critical variable for subsequent implant osseointegration. Recent biomechanical studies evaluating the consequences of site preparation led us to rethink the design of bone-cutting drills, especially those intended for implant site preparation. We present here a novel drill design that is designed to efficiently cut bone at a very low rotational velocity, obviating the need for irrigation as a coolant. The low-speed cutting produces little heat and, consequently, osteocyte viability is maintained. The lack of irrigation, coupled with the unique design of the cutting flutes, channels into the osteotomy autologous bone chips and osseous coagulum that have inherent osteogenic potential. Collectively, these features result in robust, new bone formation at rates significantly faster than those observed with conventional drilling protocols. These preclinical data have practical implications for the clinical preparation of osteotomies and alveolar bone reconstructive surgeries.

Use of a Resin-Bonded Bridge to Replace a Congenitally Missing Lateral Incisor: Treatment of "Intrusion" of Teeth.

Craniofacial growth is an important factor to consider when providing dental implant treatment for adolescents to replace missing teeth. Ongoing longitudinal observation has demonstrated that such tooth replacements may appear intruded over time, because there may be ongoing downward and anterior movement of both the alveolus and the teeth at a rate exceeding that of the dental implant, which acts like an ankylosed unit. This case reports on a 23.5-year-old female patient who, at age 16, had orthodontics completed and was left with a space where the maxillary right lateral incisor was congenitally missing with the hope of future restoration with a dental implant. A resin-bonded bridge had been placed to fill the space in the interim. After approximately 7.5 years, the bridge loosened and the patient sought an implant option as its replacement. Clinical images revealed that the bridge, which contained two bonded wings, may have limited physiologic growth, causing both the maxillary right central incisor and canine to appear intruded compared with the left central incisor and canine. This case illustrates, at the very least, that growth and development may not be complete in females aged 16 years and that the way in which a missing tooth is replaced must be carefully considered given the impact that ongoing growth and development may have on restorative care. Moreover, further growth and development may also impact adults.

The all-on-four treatment concept: a systematic review.

PURPOSE: The study aims to evaluate the all-on-four treatment concept with regard to survival rates (SRs) of oral implants, applied fixed dental prostheses (FDPs) and temporal changes in proximal bone levels. MATERIALS AND METHODS: A systematic review of publications in English and German was performed using the electronic bibliographic database MEDLINE, the Cochrane Library, and Google. Hand searches were conducted of the bibliographies of related journals and systematic reviews. The authors performed evaluations of articles independently, as well as data extraction and quality assessment. Data were submitted the weighted least-squared analysis. RESULTS: Thirteen (487 initially identified) papers met inclusion criteria. A number of 4,804 implants were initially placed, of which 74 failed, with a majority of failures (74%) within the first 12 months. A total of 1,201 prostheses were incorporated within 48 hours after the surgery. The major prosthetic complication was the fracture of the all-acrylic FDP. The mean cumulative SR/SR ± (standard deviation) (36 months) of implants and prostheses were 99.0 ± 1.0% and 99.9 ± 0.3%, respectively. The averaged bone loss was 1.3 ± 0.4 mm (36 months). No statistically significant differences were found in outcome measures, when comparing maxillary versus mandibular arches and axially versus tilted placed implants. CONCLUSION: The available data provide promising short-term results for the all-on-four treatment approach; however, current evidence is limited by the quality of available studies and the paucity of data on long-term clinical outcomes of 5 years or greater. In terms of an evidence-based dentistry, the authors recommend further studies designed as randomized controlled clinical trials and reported according to the CONSORT statement.

Lifelong craniofacial growth and the implications for osseointegrated implants.

PURPOSE: The sequence of observations presented is intended to alert the dental profession to complications that may occur when teeth and implants co-exist and subtle adult craniofacial growth occurs. MATERIALS AND METHODS: The authors' observations of partially edentulous implant restorations with more than 20 years of follow-up included some observed changes relative to patients' remaining teeth and jaw structures. These changes, which were not easily explained and appeared to be random deviations from expected implant-restorative stability, conformed with research findings of craniofacial growth continuing into adulthood. The authors identified several distinct areas in which such adult craniofacial growth could potentially influence the relationship of implant restorations to the remaining teeth and jaw structure. RESULTS: Potential esthetic, occlusal, and periodontal ramifications of continued adult craniofacial growth were found to include changes in occlusion, opened contact as a result of teeth migration, and changes in anterior esthetic results. The latter may include labialization of the anterior implant restoration and a progressive discrepancy of the cervical gingival margin of the implant restoration relative to the adjacent teeth. Cases are presented showing poor sequellae of treatment due to growth occurring after the assumption was made that a stable jaw dimension had been reached. While continued adult craniofacial growth sufficient to cause clinical problems is not common, it is also presently not predictable. CONCLUSION: When changes in tooth position relative to implant restorations secondary to long-term adult growth occur, they can cause problems that are difficult or even impossible to correct. Future research will ideally enable identification of patients at risk for developing such problems.

Colocação de implantes Mk IV em áreas ósseas comprometidas e com enxerto: resultados radiográficos em 61 sítios de 27 pacientes com acompanhamento longitudinal entre três e sete anos / Placement of brånemark mk IV implants in compromised and grafted bone: radiographic outcome of 61 sites in 27 patients with 3- to 7-year follow-ups

Objetivo: sítios onde osso é reduzido em altura ou qualidade criam desafios na reconstrução estética e no suporte para carregamento, gerando maior risco de falha. O sistema Mk IV com superfície TiUnite foi especialmente desenhado para colocação em osso macio. Este artigo descreve os resultados pós-carregamento de 103 implantes Mk IV, com ênfase na preservação óssea em sítios ósseos comprometidos durante remodelamento precoce, estabilidade e conexão do pilar, após três e sete anos de colocação dos implantes. Material e Métodos: uma série de 103 implantes Mk IV (4 mm de diâmetro, 10 mm de comprimento) foi colocada na maxila de 25 mulheres e 14 homens; 23 pacientes também receberam enxertos ósseos em etapas e dois passaram pelo aumento do alvéolo e enxertos. Áreas com infecções prévias foram preparadas mecanicamente e quimicamente. Para garantir estabilidade inicial primária, o tamanho da osteotomia e o número de entradas foi minimizado. Após um protocolo de carregamento tardio, todos os pacientes receberam próteses parciais fixas. Para análise da estabilidade óssea, os níveis ósseos marginais nos aspectos mesiais e distais foram mensurados com sete vezes de aumento por um radiologista envolvido no tratamento. Resultados: três implantes foram perdidos, um implante nunca foi carregado embora tivesse osseointegrado, 14 implantes não estavam disponíveis para acompanhamento após a conexão do pilar e cinco possuíam qualidade radiográfica inadequada. A perda óssea marginal entre a inserção do implante e o carregamento foi 1,21 ± 0,86 mm (n = 80). As diferenças nos níveis de remodelamento ósseo em sítios enxertados e não enxertados não foi significativa. Os dados foram relatados em 103 implantes em 39 pacientes consecutivos até a conexão do pilar, com acompanhamento radiográfico entre três e sete anos pós-colocação para 27 pacientes...

Placement of Brånemark Mk IV implants in compromised and grafted bone: radiographic outcome of 61 sites in 27 patients with 3- to 7-year follow-ups.

OBJECTIVE: Sites in which bone is reduced in quality or height create challenges in esthetic reconstruction and loading support, which leads to a higher risk of failure. The Mk IV system with a TiUnite surface was designed specifically for placement in soft bone. This paper describes postloading outcomes of 103 Mk IV implants, with a focus on bone preservation in compromised bone sites during early remodeling, stability after abutment connection, and a 3- to 7-year follow-up from implant placement. METHOD AND MATERIALS: A series of 103 4-mm (diameter), ≤ 10-mm (length) Mk IV implants were placed in the maxillae of 25 females and 14 males. Twenty-three patients also received staged bone grafts, and two underwent socket augmentation as well as grafts. Areas of previous infection were prepared mechanically and chemically. To ensure primary implant stability, the size of the osteotomy and the number of entries were minimized. Following a delayed loading protocol, all patients were restored with fixed partial dentures. For analysis of bone stability, the marginal levels on the mesial and distal aspects of the implants were measured at 7x magnification by a radiologist not involved in the treatment. RESULTS: Three implants were lost, 1 implant was never loaded although it integrated, 14 implants were not available for follow-up after abutment correction, and 5 had poor-quality radiographs. The mean marginal bone loss between implant insertion and loading was 1.21 ± 0.86 mm (n = 80). The differences in bone-remodeling levels in grafted and nongrafted sites were not significant. Data are reported on 103 implants in 39 consecutive patients through abutment connection, with radiographic follow-up from 3 to 7 years postimplant placement on 27 patients. CONCLUSION: It is critical to ensure optimal three-dimensional orientation and minimize site preparation, particularly when placing implants in compromised bone. With bone of poor preoperative density using a customized site preparation technique, excellent short-term implant survival and long-term bone stability have been demonstrated. Further follow-up will determine whether the Mk IV implant is the optimal design for compromised bone, including associated soft tissue stability.

Parameters for successful implant integration revisited part I: immediate loading considered in light of the original prerequisites for osseointegration.

PURPOSE: With the increasing popularity and publication of loading implants at the time of placement, including at time of dental extraction and simultaneous with reconstructive procedures, the objective was to evaluate known variables identified for a traditional unloaded healing period and determine the applicability of these variables to immediate loading. MATERIALS: A total of 124 published reports available as of January 2008 that contained information about loading from the time of surgery up to 3 months postsurgically were examined in light of published variables affecting osseointegration based on a 2 stage surgical approach. METHODS: The articles were examined to differentiate between immediate loading (within the initial 48 hours) and early/delayed loading of implants. Success or survival criteria were noted, and where reasons for failure were available, categorized according to six variables considered as determinants for maintaining a long-term bone-to-implant contact. RESULTS: Approximately 60 of the 124 reports described immediately loading implants within 48 with single-tooth, partial, and full-arch restorations, as well as implant overdentures. The implant success or survival rates ranged from 70.8% to 100%. Most studies considered implant survival to be the only criterion for success. CONCLUSIONS: Of six parameters identified in 1981 as influencing osseointegration, two parameters (the status of the bone/implant site and implant loading conditions) appear to have diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may affect immediate loading positively or adversely.

Parameters for successful implant integration revisited part II: algorithm for immediate loading diagnostic factors.

Immediate loading of dental implants has become a widely reported practice with success rates ranging from 70.8% to 100%. Although most studies have considered implant survival to be the only measure of success, a better definition includes the long-term stability of the hard and soft tissues around the implant(s) and other adjacent structures, as well as the long-term stability of all the restorative components. The parameters identified in 1981 by Albrektsson and colleagues as influencing the establishment and maintenance of osseointegration have been reconsidered in relation to immediate loading to improve the chances of achieving such success. Two of the six parameters (status of the bone/implant site and implant loading conditions) have preoperative diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may compensate for less-than-ideal site and loading conditions. Factors affecting the outcome of immediate loading are reviewed to assist clinicians attempting to assess its risks and benefits.

Technique for placement of oxidized titanium implants in compromised maxillary bone: prospective study of 290 implants in 126 consecutive patients followed for a minimum of 3 years after loading.

PURPOSE: This prospective clinical study evaluated the performance of 290 tapered, anodic oxidized (TiUnite) titanium implants placed in compromised bone in a consecutive series of 126 patients. MATERIALS AND METHODS: Inclusion criteria were: (1) a need for dental implants in either a single-tooth or partially edentulous segment, (2) sufficient medical fitness to undergo the procedure, (3) enough bone to enable placement of a 10-mm or longer implant, and (4) compromised bone, as judged by computerized tomography and confirmed by clinical findings, in at least one implant site. Implants were placed and left unloaded for at least 6 months (mean 9.9 +/- 3.9 months) before placement of the first provisional prosthesis and followed for at least 3 years after loading. Marginal bone was measured by an independent radiologist. RESULTS: A second-stage uncovering was required for approximately half the implants. Failure of osseointegration was observed for only two implants; all other implants provided the intended prosthetic support during the entire observation period. The overall implant survival rate after 3 years of loading was 99.3%. The average mean changes in the marginal bone level showed stability (-2.70 mm, -2.67 mm, and -2.74 mm at 1, 2, and 3 years postloading, respectively). CONCLUSIONS: Using a modified surgical technique that minimized the osteotomy dimensions, tapered implants with an oxidized surface proved to be a predictable support for fixed prostheses in both grafted and ungrafted compromised bone. Marginal bone levels were stable throughout at least 3 years of follow-up.