Diagnostic Classification and Design Considerations for Implant-Supported Fixed Partial Dentures and Screw Access Channel: The ABC/PBC and SAC Classifications.

Logical categorization of implant-supported fixed partial dentures (ISFPDs) based on implant angulation, abutment type, and screw access channel (SAC) design for screw-retained restoration is not available in the literature. This article proposes a simple classification system to describe implant angulations and prosthesis design affecting abutment selection (engaging or nonengaging) for ISFPDs. An additional classification that addresses screw access channel designs is also introduced. These classifications provide clear interpretation of clinical scenarios for ISFPD design consideration and a basis for categorization of future complications. The angulation-based and prosthetic-based classifications simplify communication regarding implant angulation and prosthesis design type for ISFPDs. The SAC classification assists in prosthetic design, factoring in function and esthetics when designing the screw access.

[Conceptual approach to classification of implant supported prosthesis for edentulous patients]. / Kontseptual'nyi podkhod k klassifikatsii protyazhennykh implantatsionnykh zameshchayushchikh konstruktsii, ispol'zuyushchikhsya u patsientov s polnoi poterei zubov.

The aim of this study was the creation of a conceptual model of the standard implant prosthetics for edentulous patients using the data of comprehensive examination and implantation prosthetics in 372 patients aged 38 to 80 years (201 women, 171 men) with 582 implant supported prosthesis of various types, supporting on implants «Nobel Replace Select/Groove¼ and «Nobel Speedy Groove¼ (3675 implants). Clinical classification of implant-supported prosthesis for edentulous patients included 5 classes: class 1 (1-2 implants) included 6.2% of implant supported prosthesis, class 2 (3-4 implant) - 19.2% of prostheses, class 3 (5-6 implants) - 30.2% of replacement structures; IV (7-10 implants) - 44%, and V - 0,3%. Restoration class was age-dependent.

Single-Rooted Extraction Sockets: Classification and Treatment Protocol.

Clinicians have many treatment techniques from which to choose when extracting a failing tooth and replacing it with an implant-supported restoration and when successful management of an extraction socket during the course of tooth replacement is necessary to achieve predictable and esthetic outcomes. This article presents a straightforward, yet thorough, classification for extraction sockets of single-rooted teeth and provides guidance to clinicians in the selection of appropriate and predictable treatment. The presented classification of extraction sockets for single-rooted teeth focuses on the topography of the extraction socket, while the protocol for treatment of each socket type factors in the shape of the remaining bone, the biotype, and the location of the socket whether it be in the mandible or maxilla. This system is based on the biologic foundations of wound healing and can help guide clinicians to successful treatment outcomes.

[Technical complications rates and plaque control of fixed dental prostheses in patients treated for periodontal disease].

OBJECTIVE: To compare the incidence of technical complications of implant-supported fixed dental prostheses in Chinese patients with a history of moderate or severe periodontitis and periodontally healthy patients(PHP) and analyze the effects of interproximal papillae patterns on food impaction and efficacy of plaque control. METHODS: A total of 103 partially edentulous patients treated with implant-supported fixed dental prostheses between December 2009 and December 2012 for a minimum 1-year follow-up period were recruited from Department of Periodontology, Peking University, School and Hospital of Stomatology. Based on the initial periodontal examination, the participants were divided into three groups: 30 PHP, 36 moderate periodontally compromised patients(mPCP) and 37 severe periodontally compromised patients(sPCP). Implant survival/loss, technical complications, plaque index, papilla index, food impaction and degree of proximal contact tightness of each patient were assessed around the implants at follow-up. According to the implant papilla index, the implants were divided into two groups: the "filling" group with the mesial and distal aspects with papilla index=3 and the "no filling" group with at least one aspect with papilla index<3. Data on implant survival, technical complications were analyzed. Comparisons of the incidence of technical complications were performed between the patients with different periodontal conditions with chi-square or Fisher's exact test. The influences of the interproximal papillae loss on food impaction and efficacy of plaque control were estimated with chi-square and Mann-Whitney U tests. RESULTS: The total implant survival rate was 100%(162/162) for all three groups. Technical complications were as following: veneer fractures(1.9%, 3/162), abutment screw loosening(1.9%, 3/162), prosthetic screw loosening(3.1%, 5/162) and decementation(3.1%, 5/162) in all subjects. No implant/screw fracture was noted. The incidence of technical complications in sPCP, mPCP and PHP did not yield statistically significant differences(P>0.05). The proportion of the implant with the mesial and distal papilla index=3 in the sPCP was less than that in the PHP and mPCP. The interproximal papillae loss did not appear to affect the food impaction and the plaque index in all three groups(P>0.05). However, for the PHP, the accumulation of plaque at buccal aspect was more in the "no filling" group compared with the "filling" group (implant plaque index[M(Q)]: 1[1] vs 0[0]), and for the sPCP, the accumulation of plaque at lingual aspect was more in the "filling" group compared with the "no filling" group(implant plaque index[M(Q)]: 1[1] vs 0[1], (P<0.05). CONCLUSIONS: The patients with a history of severe periodontitis did not exhibit more technical problems compared with the periodontally healthy patients. The interproximal papillae loss did not show a negative impact on the plaque control and food impaction. However, for the sPCP, changing the morphology and the position of the interproximal contact point to reduce the interdental black triangle may lead to accumulation of plaque at lingual aspect. More attention should be placed on the morphology design of prosthesis, but not the papillae filling up the interproximal space.

[Implant-borne prosthetic rehabilitation in patients with cleft lip and palate: A retrospective study on 43 patients]. / Réhabilitation implanto-portée des patients porteurs de fentes labio-alvéolo-palatines : étude rétrospective sur 43 patients.

INTRODUCTION: Implant-borne rehabilitation in cleft lip and palate patient are aimed to allow for good orofacial functions, stable occlusion, and adequate support for the naso-labial region. The goal of our study was to evaluate the functional and esthetic results of the implant-born dental rehabilitation of the cleft lip and palate patients in our department. MATERIAL AND METHODS: Our retrospective study concerned patients operated between 1995 and 2010 in our department. All included patients suffered from a cleft alveolus and lip, with or without cleft palate. Dental implants were placed in the bone-grafted alveolus and the end of growth and at distance from the bone graft procedure. Criteria of implant survival and implant-borne rehabilitation success were defined. RESULTS: A total of 78 implants were placed in 43 patients between 1995 and 2010. Two implants were lost (implant survival rate: 97.4%). Despite this loss, all the patients could be rehabilitated with good functional and esthetic results. DISCUSSION: Implant-borne rehabilitation is a reliable solution for prosthetic rehabilitation in patients with cleft lip and palate. This solution allows for avoiding removable prosthesis and dental mutilation.

Short implants: are they a viable option in implant dentistry?

Short-length implants (<10 mm) can be used effectively in atrophic maxillae or mandibles even with crown/implant ratios that previously would have been considered excessive. Short implants can support either single or multiple units and can be used for fixed prostheses or overdentures. The use of short-length implants may avoid the need for complicated bone augmentation procedures, thus allowing patients who were either unwilling or unable for financial or medical reasons to undergo these advanced grafting techniques to be adequately treated.

Partial Edentulism based on Kennedy's classifcation: an epidemiological study.

BACKGROUND: The aim of this study was to determine the incidence of different Kennedy's classes of partial edentulism during 18 months period. MATERIALS AND METHODS: Patients were clinically examined for various Kennedy's classes of partial edentulism in the outpatient department (OPD), prosthodontics, GPRDCH, Kurnool (Andhra Pradesh). RESULTS: Of the total 1,420 OPD patients, Kennedy's class III was the most frequent classification encountered (62%) and followed by Kennedy's class I (18%), class II (11%), and class IV (9%) in decreasing order. CONCLUSION: The patients with various Kennedy's classes of partial edentulism can be offered various treatment modalities like removable cast partial dentures, fixed partial dentures, over dentures and implant supported dentures. This study can be crucial for screening the population for incidence of tooth loss as a factor of gender and age. Clinical significance: Tooth loss appears to have an important role in the loss of esthetics and mastication. Study of incidence of various classes of partial edentulism provides clinically useful information for dental training and continuing education.

Implant-prosthodontic classification of the edentulous jaw for treatment planning with fixed rehabilitations.

PURPOSE: This study aimed to develop a classification of edentulous jaws for use as a diagnostic tool during implant-prosthodontic treatment planning. MATERIALS AND METHODS: The morphology of 200 fully edentulous alveolar ridges (100 maxillae, 100 mandibles) was assessed with cone beam computed tomography. Generic implants (length: 8 mm; diameter: 4.1 mm) were used. To develop the classification system, the feasibility of virtually placing the implants without vertical ridge augmentation was considered. Potential implant sites were evaluated in terms of ridge width and described as either type A (no horizontal augmentation required) or type B (horizontal augmentation required). A descriptive statistical analysis of subjects' age, sex, and arch classification was performed. RESULTS: In total, 880 implants were virtually planned. Based on alveolar ridge height, four arch patterns were identified (C1 to C4), providing a basis for prosthodontic planning with either removable or fixed implant-supported restorations. The frequencies of each category were as follows: C3 (n = 62, 62%), C4 (n = 16, 16%), C2 (n = 12, 12%), and C1 (n = 10, 10%) for the maxilla and C3 (n = 36, 36%), C4 (n = 31, 31%), C1 (n = 24, 24%), and C2 (n = 9, 9%) for the mandible. CONCLUSION: The proposed classification of the edentulous arch represents a useful tool for communication between clinicians when planning implant-supported rehabilitations.

Evidenced-based criteria for differential treatment planning of implant restorations for the partially edentulous patient.

Evidence-based criteria for differential implant planning for the partially edentulous patient have been lacking despite the exponential use of implant reconstructions. Anecdotal reports are often the basis for training of dental students and the continuing education of dentists and specialists. Decision-making metrics for optimal dental treatment are best predicated on a comprehensive assessment of the systemic, local, and patient-mediated factors evaluated through the lens of the best available evidence. The purpose of this article is to delineate the benefits/risks/alternatives calculus for patients considering implant restorations.

Treatment outcome in patients with peri-implantitis in a periodontal clinic: a retrospective study.

BACKGROUND: The number of placed implants has grown during the past decade, and the prevalence of peri-implantitis has increased. The purpose of the present study is to investigate the treatment outcome of peri-implantitis and to identify factors influencing the treatment success rate. METHODS: The study was conducted as a retrospective longitudinal study on a referral population. The material included 382 implants with peri-implantitis in 150 patients. Peri-implantitis was defined as presence of pocket depths ≥5 mm, bleeding at probing and/or suppuration, and the presence of implant radiographic bone loss ≥3 mm or bone loss comprising at least three threads of the implant. Variance analyses, χ(2) analyses, and logistic regression analysis were used for data analyses. RESULTS: The mean age of the participants at baseline was found to be 64 years (range: 22 to 87 years). The mean ± SD follow-up time was 26 ± 20 months, and the mean time between implant installation and baseline was 6.4 years (range: 1 to 20 years). Periodontal flap surgery with osteoplasty was the most common type of therapy (47%), and regenerative surgery procedures with bone substitute materials were chosen in 20% of the cases. The mean success rate at patient level was 69%. The results of the logistic regression analyses showed that the success rate was significantly lower for individuals with the diagnosis of severe periodontitis, severe marginal bone loss around the implants, poor oral hygiene, and low compliance. CONCLUSION: The effectiveness of the peri-implantitis therapy was impaired by severe periodontitis, severe marginal bone loss around the implants, poor oral hygiene, and low compliance.

A retrospective analysis of replacing dental implants in previously failed sites.

OBJECTIVE: Overall first-year failure rate for dental implants may reach 3%-8% as the result of various complications. Accordingly, reimplantation accounts for an ever-growing portion of clinic's practice. The purpose of the present study was to evaluate the survival rate of dental implants that were performed in sites where failed implants were previously removed and to evaluate the factors affecting outcome. STUDY DESIGN: Three certified oral and maxillofacial surgeons inserted 144 implant replacement in previously failed sites in 144 patients (1994-2009). Clinical and epidemiologic data were collected retrospectively and analyzed regarding survival rates. RESULTS: Survival rate of the implants replacing previously failed ones was 93% (133/144). A third placement in the same site was performed in 7 of 11 patients with a survival rate of 85% (6/7) up to the last follow-up. No correlations were found between replaced implant failures with any of the parameters examined. CONCLUSIONS: Within the limits of the present study, it can be concluded that a previous implant failure should not discourage practitioners from a second or even a third attempt.

Rehabilitation of atrophic posterior maxilla with zygomatic implants: review.

The objective of this study was to review the published literature to evaluate treatment success with zygomatic implants in patients with atrophic posterior maxilla. Studies from 1987 to 2010 were reviewed. In each study, the following were assessed: indications for treatment, number of patients, number of implants, length and diameter of the implants, surgical technique, prosthetic rehabilitation, success rate, complications, and patient satisfaction. Sixteen studies were included, with a total of 941 zygomatic implants placed in 486 patients. The follow-up periods ranged from 12 to 120 months. Three different surgical techniques were used to place zygomatic implants: intrasinus implants with the classic sinus window technique, the sinus slot technique, and extrasinus zygomatic implants. The most common restoration used was fixed prosthesis, with either delayed loading after 3-6 months (89%-100% success) or immediate loading (96.37%-100% success). The weighted average success rate was 97.05%, and the most frequent complication was maxillary sinusitis. The general level of patient satisfaction was high. Zygomatic implants have a high success rate and constitute a suitable alternative to treat severe posterior maxillary atrophy.

Osseointegrated implant rehabilitation of irradiated oral cancer patients.

PURPOSE: The aim of this study is to analyze implant survival in patients who received radiotherapy treatment for oral malignancies and in patients who had suffered mandibular osteoradionecrosis. MATERIALS AND METHODS: We reviewed retrospectively 225 implants placed in 30 patients who had received radiotherapy as part of the oncologic treatment. Radiation doses ranged between 50 and 70 Gy. 39 implants were placed after a combined treatment of radiotherapy and chemotherapy. Data referred to tumour type and reconstruction, presence of osteoradionecrosis, region of implant installation and type of prostheses were recorded. Survival rates were calculated with cumulative Kaplan-Meier survival curves and compared between different groups with a log-rank test. RESULTS: 152 osseointegrated implants were placed in patients who presented previous reconstruction procedure. Five patients developed osteorradionecrosis as a complication of the radiotherapy treatment. Once osteoradionecrosis had healed in these patients, 41 implants were installed. The overall 5 year survival rate in irradiated patients was 92.6%. Irradiated patients had a marginally significantly higher implant loss than non-irradiated patients. (p = 0.063). The 5 year survival rate in the osteoradionecrosis group was of 48.3% and in the non-osteoradionecrosis group 92.3%, with a statistically significant difference between both groups. (p = 0.002). CONCLUSION: Osseointegrated implants enhance oral rehabilitation in most irradiated patients, even being an acceptable option for patients who had suffered osteoradionecrosis. Totally implant supported prostheses are recommended after irradiation providing functional, stable and aesthetically satisfactory rehabilitation.

Prótesis híbrida (PH): enfoque actual de la prótesis implantoasistida híbrida (PIAH) / Hybrid prosthesis (HP): a current approach to implant-supported hybrid prosthesis

Oportunamente, en publicaciones dedicadas a la prótesis híbrida (PH), la definimos como la conjunción de dos especies, la prótesis total removible (PTR) y la prótesis parcial fija (PPF). Decíamos en aquella oportunidad, que utilizamos tres tipos de PH, a las que denominamos de baja, media y alta complejidad. Este tipo de prótesis está indicada en rebordes exiguos no reconstruidos parcialmente y con implantes no distribuidos en posición ideal. Antes de realizar nuestro enfoque actual del tema, nos parece oportuno hacer una síntesis de aquellos capítulos en los que desarrollamos las técnicas constructivas de las híbridas de maxilar inferior y cuestionábamos la utilización de las híbridas para el maxilar superior. Finalmente, daremos los motivos por los cuales, en la actualidad, indicamos la PH en el maxilar superior, y desarrollaremos dos nuevos recursos, diseñados por nosotros, para facilitar la eficiencia de la PH: uno para mejorar la fijación de las partes de la clásica PH de alta complejidad y otro para obtener mayor precisión en la fijación de la PH de maxilar superior.

Prótesis híbrida (PH): enfoque actual de la prótesis implantoasistida híbrida (PIAH) / Hybrid prosthesis (HP): a current approach to implant-supported hybrid prosthesis

Oportunamente, en publicaciones dedicadas a la prótesis híbrida (PH), la definimos como la conjunción de dos especies, la prótesis total removible (PTR) y la prótesis parcial fija (PPF). Decíamos en aquella oportunidad, que utilizamos tres tipos de PH, a las que denominamos de baja, media y alta complejidad. Este tipo de prótesis está indicada en rebordes exiguos no reconstruidos parcialmente y con implantes no distribuidos en posición ideal. Antes de realizar nuestro enfoque actual del tema, nos parece oportuno hacer una síntesis de aquellos capítulos en los que desarrollamos las técnicas constructivas de las híbridas de maxilar inferior y cuestionábamos la utilización de las híbridas para el maxilar superior. Finalmente, daremos los motivos por los cuales, en la actualidad, indicamos la PH en el maxilar superior, y desarrollaremos dos nuevos recursos, diseñados por nosotros, para facilitar la eficiencia de la PH: uno para mejorar la fijación de las partes de la clásica PH de alta complejidad y otro para obtener mayor precisión en la fijación de la PH de maxilar superior.(AU)

Prospective clinical evaluation of 1920 Morse taper connection implants: results after 4 years of functional loading.

PURPOSE: This study evaluated the survival rate and the clinical, radiographic and prosthetic success of 1920 Morse taper connection implants. MATERIAL AND METHODS: One thousand nine hundred and twenty Morse taper connection implants were inserted in 689 consecutive patients, from January 2003 until December 2006. Implants were clinically and radiographically evaluated at 12, 24, 36 and 48 months after insertion (mean follow-up per implant: 25.42 months). Modified plaque index (mPI), modified sulcus bleeding index, probing depth (PD) and the distance between implant shoulder and first crestal bone-implant contact (DIB) were measured in mm. Success criteria included the absence of suppuration and clinically detectable implant mobility, PD<5 mm, DIB<1.5 mm after 12 months of functional loading and not exceeding 0.2 mm for each following year, the absence of recurrent prosthetic complications at the implant-abutment interface. Prosthetic restorations were fixed partial prostheses (364 units), single crowns (SCs: 307 units), fixed full-arch prostheses (53 units) and overdentures (67 units). RESULTS: The overall cumulative implant survival rate was 97.56% (96.12% in the maxilla and 98.91% in the mandible). The cumulative implant success rate was 96.61% (95.25% in the maxilla and 98.64% in the mandible). Only a few prosthetic complications were reported (0.65% of loosening at implant-abutment interface in SCs). CONCLUSION: The use of Morse taper connection implants represents a successful procedure for the rehabilitation of partially and completely edentulous arches. The absence of an implant-abutment interface (microgap) is associated with minimal crestal bone loss. The high mechanical stability significantly reduces prosthetic complications.

A classification system to measure the implant-abutment microgap.

PURPOSE: A large microgap at the implant-abutment interface has been reported to result in adverse effects, including screw loosening, abutment rotation, and abutment fracture. However, a standardized classification of the implant-abutment interface has not been established. The purposes of this investigation were (1) to propose a classification system based on the horizontal and vertical microgap of the implant-abutment interface and (2) to compare the implant-abutment interface in 4 groups of abutments. MATERIALS AND METHODS: Forty-eight randomly selected external hexagonal implants were paired with (1) machined titanium abutments, (2) premachined palladium abutments cast-on with palladium alloy, (3) plastic burnout abutments cast with nickel chromium alloy, and (4) plastic burnout abutments cast with cobalt chromium alloy. A comparison of the horizontal and vertical microgaps at the implant-abutment interface was completed at 8 locations on each specimen to the nearest micrometer using an optical microscope with a magnification of 150x. Group means and significant differences between groups were determined by analysis of variance and Tukey multiple-comparisons post-hoc analysis. P < .05 was the threshold for statistical significance. RESULTS: There was no significant difference between groups with respect to vertical misfit. For horizontal misfit, machined titanium abutments presented significantly higher horizontal misfit compared to other groups (P < .001). Premachined cast-on abutments had significantly higher horizontal misfit than cast NiCr abutments (P < .001). In the proposed classification system, 23% of all sites measured at the implant-abutment interface had an ideal relationship, 34% had a horizontal discrepancy only, 4% had a vertical discrepancy only, and 39% had both vertical and horizontal discrepancies. CONCLUSION: The proposed implant-abutment classification system demonstrated a way to characterize and compare the microgap at the implant-abutment interface.

Terminology for implant prostheses.

The use of systematic terminology for implant prostheses can simplify communication within the scientific community. However, a review of the current literature demonstrates the lack of uniformity in this field. It is the purpose of this manuscript to suggest uniform terminology based on conventional prosthodontic terms that will simplify communication in the profession.

Retrospective clinical study of Osseotite implants: zero- to 5-year results.

PURPOSE: Over the last few years, particular attention has been paid to the implant surface and its influence on the formation and maintenance of surrounding bone. The surface of Osseotite implants (Implant Innovations) is produced by a process of thermal etching, which produces a surface with an average roughness that is twice that of machined implants produced by the same manufacturer. In addition to reducing osseointegration time, this factor appears to favor its maintenance over time. This study presents the results of a clinical trial of Osseotite implants. MATERIALS AND METHODS: Five hundred fifty-five Osseotite implants were placed in 244 patients over 5 years, between September 1996 and September 2001. The average follow-up period from implant placement was 26 months (SD 13.1). RESULTS: After the first surgical stage, 8 failures were noted in 6 patients. Life table analysis showed a cumulative survival rate of 98.5%, but no implant was lost after prosthetic loading, with a 100% survival rate both for the mandible and for the maxilla. For the prosthetic loading time, only the implants with more than 12 months of loading were considered, obtaining an average prosthetic loading time of 34 months (SD 9.2). DISCUS SION: The implant survival rate after loading was 100% both in the anterior and posterior regions, and no difference was noted in relation to the different types of prostheses, or length and width of implants. CONCLUSION: The results obtained in this retrospective study population revealed an acceptable survival rate for these implant-supported restorations.

Immediate/early loading of dental implants: a report from the Sociedad Española de Implantes World Congress consensus meeting in Barcelona, Spain, 2002.

BACKGROUND: Immediate/early loading protocols are becoming frequently used in implant dentistry, but the prerequisites for achieving good results and the limitations of such protocols are not fully known. Moreover, the terminology used in immediate/early loading is still confusing. PURPOSE: The purpose of this article is to present the outcome of a consensus meeting on immediate/early loading. MATERIALS AND METHODS: A consensus meeting was organized during the Sociedad Española de Implantes World Congress in Barcelona on May 23, 2002, with the objective to present and discuss the experiences from immediate/early loading protocols in dental implant treatment. The purpose was also to discuss definitions of the terminology used in immediate/early loading. The consensus meeting agenda included presentations from invited experts, followed by a consensus discussion. RESULTS: A consensus statement was agreed on. CONCLUSIONS: Multiple independent investigators have demonstrated that immediate/early loading of implants is possible in many clinical situations; however, additional documentation is required.