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Santosh Dhakal,1,2 Xingguo Cheng,3 John Salcido,3 Sankar Renu,1,2 Kathy Bondra,1,2 Yashavantha Shaan Lakshmanappa,1,2 Christina Misch,1,2 Shristi Ghimire,1,2 Ninoshkaly Feliciano-Ruiz,1,2 Bradley Hogshead,1,2 Steven Krakowka,4 Kenneth Carson,3 Joseph McDonough,3 Chang Won Lee,1,2 Gourapura J Renukaradhya1,2 1Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA; 2Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA; 3Pharmaceuticals and Bioengineering Department, Chemistry and Chemical Engineering Division, Southwest Research Institute, San Antonio, TX 78238-0510, USA; 4The Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA Background: Influenza (flu) is a constant threat to humans and animals, and vaccination is one of the most effective ways to mitigate the disease. Due to incomplete protection induced by current flu vaccines, development of novel flu vaccine candidates is warranted to achieve greater efficacy against constantly evolving flu viruses. Methods: In the present study, we used liposome nanoparticle (

An abstract is presented to the article "Factors affecting late implant bone loss: A retrospective analysis."

Purpose: To establish consensus-driven guidelines that could support the clinical decision-making process for implant-supported rehabilitation of the posterior atrophic maxilla and ultimately improve long-term treatment outcomes and patient satisfaction., Materials and Methods: A total of 33 participants were enrolled (18 active members of the Italian Academy of Osseointegration and 15 international experts). Based on the available evidence, the development group discussed and proposed an initial list of 20 statements, which were later evalu-ated by all participants. After the forms were completed, the responses were sent for blinded ana-lysis. In most cases, when a consensus was not reached, the statements were rephrased and sent to the participants for another round of evaluation. Three rounds were planned., Results: After the first round of voting, participants came close to reaching a consensus on six statements, but no consensus was achieved for the other fourteen. Following this, nineteen statements were rephrased and sent to participants again for the second round of voting, after which a consensus was reached for six statements and almost reached for three statements, but no consensus was achieved for the other ten. All 13 statements upon which no consensus was reached were rephrased and included in the third round. After this round, a consensus was achieved for an additional nine statements and almost achieved for three statements, but no consensus was reached for the remaining statement., Conclusion: This Delphi consensus highlights the importance of accurate preoperative planning, taking into consideration the maxillomandibular relationship to meet the functional and aesthetic requirements of the final restoration. Emphasis is placed on the role played by the sinus bony walls and floor in providing essential elements for bone formation, and on evaluation of bucco-palatal sinus width for choosing between lateral and transcrestal sinus floor elevation. Tilted and trans-sinus implants are considered viable options, whereas caution is advised when placing pterygoid implants. Zygomatic implants are seen as a potential option in specific cases, such as for completely edentulous elderly or oncological patients, for whom conventional alternatives are unsuitable.

Purpose: To investigate whether implant position (adjacent to teeth/implants vs most distal position in the arch) influences the clinical outcomes of short (≤ 6 mm) non-splinted implants., Materials and Methods: A systematic electronic search of human randomised clinical trials and prospective cohort studies was performed using the PubMed, Embase and Cochrane Central Register of Controlled Trials (Central) databases. A manual search of implant-related journals was also performed. A meta-analysis was conducted to compare survival rate, marginal bone loss and prosthetic complications based on implant position., Results: Overall, 11 studies were included to give a total of 388 non-splinted short implants (269 adjacent, 119 distal) followed up over a period ranging from 12 to 120 months. No significant differences in survival were found when comparing adjacent and distal positioning for both arches, and no significant differences were found for marginal bone loss or prosthetic complications between groups regardless of position., Conclusions: Short implants supporting single crowns presented similar outcomes when placed in the most distal position in the arch or between adjacent teeth or other implants., Competing Interests: The authors do not have any financial interests, either direct or indirect, in the products mentioned in the present study.

An important mission statement for modern dentistry is to maintain patients' implants and teeth for a lifetime. As a corollary, a standardized dental caries risk classification should provide the basis for evidence-based specific therapies. This paper proposes that interproximal caries lesions, also termed "restorative invasion," which destroys natural anatomical tooth structure with periodontal and occlusal sequelae, is a key factor in the cascade of destruction of the dentition and periodontitis. Thus it can serve as the basis for caries risk assessment. The standardized Dental Risk Classification system proposed here can provide a basis for therapeutic modalities as well as for public health assessment and insurance reimbursement.

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.

We present total energy and force calculations for the (GaN)1-x(ZnO)x alloy. Site-occupancy configurations are generated from Monte Carlo (MC) simulations, on the basis of a cluster expansion model proposed in a previous study. Local atomic coordinate relaxations of surprisingly large magnitude are found via density-functional calculations using a 432-atom periodic supercell, for three representative configurations at x = 0.5. These are used to generate bond-length distributions. The configurationally averaged composition- and temperature-dependent short-range order (SRO) parameters of the alloys are discussed. The entropy is approximated in terms of pair distribution statistics and thus related to SRO parameters. This approximate entropy is compared with accurate numerical values from MC simulations. An empirical model for the dependence of the bond length on the local chemical environments is proposed.

Conventional dentoalveolar osseous augmentation procedures for creating bone volume for dental implant placement often involve the use of grafting materials with or without barrier membranes to foster selective cell and tissue repopulation. A study was conducted to determine the efficacy of equine particulate bone (Equimatrix, Osteohealth) to augment the creation of new bone and preserve the volume of bone at extraction sites for the purpose of placing an implant in an optimal position for restoration. Clinical and histologic evidence supported the suitability of equine particulate bone for extraction site augmentation that allowed dental implant placement after a 6-month healing period.

Purpose: This case report documents the histological, histomorphometric, and radiographic effects of a new radiated-preserved bone allograft for sinus elevation procedures., Materials and Methods: This unique bone substitute differs from other forms of bone allograft processed through the standard cryopreservation method. Histology from bone biopsy core samples revealed newly formed bone with a well-organized lamellar bone structure in general and remaining particles were observed in contact with surrounding newly-formed bone., Results: Histomorphometric results demonstrated an average new bone formation of 31.8%. Radiographic linear data demonstrated an 8.49% +/- 6.77% graft resorption from baseline to 6 months., Conclusion: The outcome of this report suggests that this bone allograft could be successfully used in sinus lifting procedures. It encourages further research of this radiated-preserved bone allograft material in oral and maxillofacial reconstruction.

The use of antimicrobials reduces the incidence of surgical wound infection in oral implantology. Antimicrobial prophylaxis is indicated in all Class 2 (clean-contaminated) surgical procedures, which include sufficient blood levels at the time of bacterial contamination of dental implant and bone graft procedures. Timing and dosage are critical to the efficacy of antibiotics. Antibiotic selection is determined mainly by the bacteria which is most likely to cause an infection from the specific procedure. The authors have developed a classification and protocol that allows the dental practitioner to properly prescribe medication based on procedural, local host and systemic factors.

Background: Dental implant thread geometry has been proposed as a potential factor affecting implant stability and the percentage of osseointegration. Therefore, the aim of this prospective, randomized, parallel arm study was to evaluate the effects of dental implant thread design on the quality and percent of osseointegration and resistance to reverse torque in the tibia of rabbits., Methods: Seventy-two custom-made, screw-shaped, commercially pure titanium implants (3.25 mm diameter x 7 mm length) were placed in the tibiae of 12 white New Zealand rabbits. Each tibia received three implants of varying thread shapes: one with a V-shaped, one with a reverse buttress, and one with a square thread design. The rabbits were sacrificed following an uneventful healing period of 12 weeks. Implants in the right tibiae underwent histologic and histomorphometric assessments of the bone-to-implant contact (BIC) and the radiographic density of surrounding bone, while implants in the left tibiae were used for reverse-torque testing. Differences between the three thread designs were examined using analysis of variance (ANOVA)., Results: Data showed that the square thread design implants had significantly more BIC and greater reverse-torque measurements compared to the V-shaped and reverse buttress thread designs, while no differences were found in radiographic bone density assessments., Conclusion: These results indicate that the square thread design may be more effective for use in endosseous dental implant systems.

The aim of this article is to present a new technique for augmentation of deficient alveolar ridges and/or correction of osseous defects around dental implants. Current knowledge regarding bone augmentation for treatment of osseous defects prior to and in combination with dental implant placement is critically appraised. The "sandwich" bone augmentation technique is demonstrated step by step. Five pilot cases with implant dehiscence defects averaging 10.5 mm were treated with the technique. At 6 months, the sites were uncovered, and complete defect fill was noted in all cases. Results from this pilot case study indicated that the sandwich bone augmentation technique appears to enhance the outcomes of bone augmentation by using the positive properties of each applied material (autograft, DFDBA, hydroxyapatite, and collagen membrane). Future clinical trials for comparison of this approach with other bone augmentation techniques and histologic evaluation of the outcomes are needed to validate these findings.

For years, dental implants have been loaded immediately upon implant placement with varying degrees of success. As clinicians' understanding of the biological and mechanical factors involved in immediate occlusal loading (IOL) has evolved, the success of these procedures has increased--particularly as a treatment option for the restoration of the edentulous mandible or the mandible that will be rendered edentulous during treatment. Due to increasing interest in this treatment alternative, the authors have provided a clear definition of the terminology associated with IOL and have demonstrated the DIEM Guidelines used to increase the success and predictability of such treatment. This presentation also introduces new implant components that simplify the clinical application of the immediate loading concept, enhancing its benefits and acceptance among dental patients and practices alike.

The presence of fibrous tissue has long been known to decrease the long-term survival of a root-form implant. Excessive loads on an osseointegrated implant may result in mobility of the supporting device, and excessive loads may also fracture an implant component or body. Although several conditions may cause crestal bone loss, one of these may be prosthetic overload. Excessive loads on the bone cause strain conditions to increase. These microstrains on the bone may affect the bone remodeling rate in a direct relationship. When strain conditions to the interfacial bone are in the mild overload zone, an increased bone remodeling response occurs, which results in a reactive woven bone formation that is less mineralized and weaker. Greater stresses may cause the interfacial strain to reach the pathologic overload zone and may cause microfracture of the bone, fibrous tissue formation, and/or bone resorption. Recent reports suggest that the bone remodeling rate next to an implant may be used to evaluate biomechanical conditions and their influence on the implant-to-bone interface. These include a number of factors, such as loading conditions, implant body surface conditions, and implant design. For a given load condition, the implant design is one of the primary factors that determine the resultant strain at the interface. A predetermined goal was established to bioengineer a dental implant to load the bone at the interface in a predetermined stress strain relationship, in order to maintain lamellar bone at the interface. A case report is presented of 2 bioengineered implants loaded for 1 year, which demonstrates that the bone was primarily lamellar in structure, the bone turnover rate was less than 5 microns/day, and was the same as the bone away from the interface. These findings corroborate those observed in a prior animal study reported with the same implant design. Although the number of implants evaluated in those 2 reports is few, they support a predetermined histological outcome.

Symphysis graft procedures are being performed in clinical practice more frequently than ever before. Convenient surgical access, proximity of donor and recipient sites, low morbidity, availability of larger quantities of bone over other donor sites, minimal resorption, no hospitalization, and minimal discomfort are some advantages of this procedure over other intraoral sites. Three types of horizontal incisions can be performed during this procedure: the sulcular, the marginal, and the alveolar mucosal. Most studies regarding the chin graft technique are more concerned with the bone graft aspect than soft tissue management. Moreover, the criteria for the selected flap design appear to be based primarily on clinical experience or the same surgical approach regardless of interfacing factors. The periodontal status, amount of bone loss, periodontal risk of root fenestration, amount of keratinized gingiva, restorations in the gingival margin, and local musculature are some of the clinical findings that should be assessed to indicate the best incision design. In this review article, the advantages, disadvantages, indications, and contraindications of each incision design will be discussed.

Implant dentistry has evolved into the mainstream of restorative practices all over the world. Maintenance of bone after tooth loss to improve or maintain facial esthetics and improved retention, function, and performance of removable restorations are only some of the advantages for the edentulous patient. No longer are implants considered only when traditional restorations cannot be fabricated. Evidence-based reports indicate implant restorations last longer than those on teeth and the abutment teeth are at less risk of loss or complication.

The goal of modern dentistry is to return patients to oral health in a predictable fashion. The partial and complete edentulous patient may be unable to recover normal function, aesthetics, comfort, or speech with a traditional removable prosthesis. The aesthetics of the edentulous patient are affected as a result of bone atrophy. Continued resorption leads to irreversible facial changes. An implant stimulates the bone and maintains its dimension in a manner similar to healthy natural teeth. As a result, the facial features are not compromised by lack of support. Implant prostheses often offer a more predictable treatment course than traditional restorations. Thus, the profession and the public are becoming increasingly aware of this dental discipline. Between 1983 and 1987 there was a tenfold increase in the number of dentists placing implants and a fourfold increase in the number of implants inserted. Manufacturers' sales have increased from a few million dollars to more than $200 million. Almost every professional journal and lay publication now carries advertisements for implants. Implant dentistry has finally been accepted by organized dentistry. All US dental schools now teach some awareness of implant dentistry. The current trend to expand the use of implant dentistry will continue until every restorative practice uses this modality for abutment support of both fixed and removable prostheses. Do not be the straggler and ignore the advantages of dental implants, because what your patients don't know can hurt them.

Reverse torque testing has been suggested to reduce the incidence of early loading failures during the first year of loading. However, the variables of bone density at stage II uncovery, the assessment of a small degree of implant rotation, and the effect of implant size and design have not been adequately evaluated. In addition, bone is weakest to shear forces, yet this is the primary force applied with reverse torque testing. This article reviews the benefits and disadvantages of reverse torque testing and suggests early crestal bone loss and failure of implants may be the result of this test, especially in less dense bone types. In addition, a nomenclature of implant failures is introduced to improve the correlation of information in the literature to the failure of implants in clinical practice.

Cortical bone grafts harvested from the posterior mandible offer several advantages for bone augmentation prior to implant placement. These grafts maintain their dense quality and exhibit minimal resorption upon incorporation. Considerable amounts of bone can be harvested from this area for use as an onlay graft. In addition, the ramus area has some inherent advantages over other donor sites. This article describes the indications and surgical technique for harvesting bone from the ramus region.

History of the tripodal mandibular subperiosteal implant and the evolution of its design are discussed. Basic principles of bone physiology are reviewed especially as they relate to bone response to loading. Modeling and remodeling are controlled by a strain-related environment. Modeling can alter the shape and volume of bone. This aspect of bone growth has been reported with transosteal implants. A case report is presented in which apparent bone growth occurred following placement of a hydroxylapatite-coated subperiosteal implant. The implant was successfully revised following an acute infection around one of the permucosal sites.

Problems with crestal bone resorption and bone adaptation to dental implants in compromised and weak bone present clinical challenges due to insufficient bone volume. Mathematical models have shown that a new, square-thread, dental implant design increases functional surface area and reduces shear loading at the implant interface. The aim of this investigation was to evaluate the ability of bone to grow between the threads of the new implant and its general biocompatibility in a canine model. Test implants were placed in the mandibles of four beagle dogs after posterior partial edentulism. Three months after implantation, the animals received independent fixed partial dentures, were followed for an additional 6 months, and then euthanized for histological analyses. Analyses revealed that bone grew between the threads and closely apposed the new implant design. Histological observations also revealed that the inferior aspect of the test implant threads were apposed by more bone than the coronal aspect, suggesting a biological advantage for the compressive load transfer mechanism of the new implant design. The results of this study revealed that the new implant design became osseointegrated with bone growing between the threads of the device.

Statement of Problem: Component fracture and screw loosening are prevalent concerns of contemporary dental implants., Purpose: This laboratory investigation examined the influence of design factors such as the platform diameter and the hex height on the mechanical strength and quality of fit of the implant-abutment interface., Material and Methods: Static and cyclic compressive bending tests were conducted on 4 and 5 mm diameter bone density-based implants. SEM evaluation of the implant-abutment interface was also conducted to assess quality of fit between the mating components.Results. The 5 mm diameter implant was stronger in both static and fatigue conditions than the 4 mm diameter implants. A comparison of the results to published literature indicated that both implants were equal to or superior to alternative prosthetic connections in an identical testing configuration., Conclusion: Test results demonstrated the validity of wide diameter implants to reduce the likelihood of component fracture in contemporary dental implant systems.

Purpose: This study sought to establish the relationships between bone density, elastic modulus, and ultimate compressive strength of trabecular bone in the human mandible, and to determine the influence that the cortical plates have on these values., Materials and Methods: Nine fresh-frozen human mandibles between the ages of 56 and 90 years were cut into anterior (incisors and canine), middle (premolars), and distal (molars) sections. Seventy-six cylindrical trabecular bone specimens with bone marrow in situ were then prepared and tested in compression in the vertical direction. These tests were performed at a constant strain rate of 0.01 s(-1) with and without the presence of the cortical plates., Result: The density of mandibular trabecular specimens with bone marrow in situ ranged from 0.85 to 1.53 g/cm3, with a mean value of 1.14 g/cm3 (SD = 0.15). With the cortical plates present, the elastic modulus ranged from 24.9 to 240.0 megapascals (MPa), with a mean value of 96.2 MPa (standard deviation (SD) = 40.6). Without the cortical plates present, the elastic modulus ranged from 3.5 to 125.6 MPa, with a mean value of 56.0 MPa (SD = 29.6). The ultimate compressive strength of the trabecular bone ranged from 0.22 to 10.44 MPa, with a mean value of 3.9 MPa (SD = 2.7)., Conclusion: This study indicates that the trabecular bone in the human mandible possesses significantly higher density, elastic modulus, and ultimate compressive strength in the anterior region than in either the middle or distal regions. The absence of cortical plates decreases the bone elastic modulus. These findings quantitatively confirm the need for clinical awareness in altering implant treatment plans and/or design in relation to bone density and the presence of the cortical plates.

This article describes the fabrication of a surgical template for planning and performing the harvest and placement of autologous bone grafts for the reconstruction of alveolar defects before implant placement. A diagnostic cast is altered to replicate the anticipated bone anatomy. The ideal bony contours for implant placement are then created on the cast to form the template. This template may then be used for treatment-planning donor sites for the harvest of corticocancellous bone grafts. The template is sterilized and used by the surgeon in procuring and placing the bone graft. This template allows communication of the prosthetic requirements of the ridge augmentation, as well as ensuring adequate volume and proper positioning of the block graft for eventual implant placement.

This interim report presents the data from a prospective study of BioHorizons, a bone quality-based implant system, with four implant designs. The surgical survival of 975 implants was 99.4%, with the survival 100% for D4 bone. Three critical phases of crestal bone loss have been identified: bone remodeling from stage I to stage II surgery; stage II uncovery to prosthesis delivery (transition period); and prosthesis delivery up to the first year of loading (early loading bone loss). The stage I to stage II uncovery crestal bone remodeling resulted in a mean vertical bone loss of 0.21 mm to 0.36 mm (SD = 0.90 mm), dependent on whether the implant became exposed in the oral cavity during osseous healing. No statistically significant difference was found among the four implant designs, diameter, bone density, or location. The stage II to prosthesis delivery mean vertical bone loss ranged from 0.12 mm to 0.20 mm. One hundred three consecutive patients (partially and totally edentulous) were restored, with 360 implants and 105 prostheses in function for a period of 12 to 26 months. No early loading implant failure occurred, and all patients with implants are in satisfactory to optimum health according to the Misch Implant Quality Scale. The mean early loading bone loss was 0.29 mm (SD = 0.99 mm). Past clinical reports in the literature indicate most failures or crestal bone loss occur by the first year of loading. This study suggests the bone quality based dental implant design minimizes overall implant failure and crestal bone loss, regardless of bone density.

Patients frequently need treatment to replace single teeth in the posterior regions. A number of different kinds of therapy have been used to treat this problem, including (1) removable partial denture, (2) acid-etched resin-retained prosthesis, (3) maintenance of the missing space, (4) a fixed partial denture, or (5) an implant-supported prosthesis. The purpose of this article is to assess the strengths and weaknesses of each of these treatments. The author concludes that single tooth implants are generally the best choice for dealing with a missing single tooth in the posterior regions of the mouth.

The posterior regions of the mouth sustain greater forces, yet often present poorer bone density. A biomechanical approach, often presented to decrease risk factors in such regions, is to increase implant surface area. Most manufacturers provide implants in various lengths. The longest implants are typically inserted into the anterior regions of the mouth, where forces of less magnitude and superior bone quality are present. A finite element analysis supports the hypothesis that implant length is a secondary parameter for stress distribution. A common approach is to enhance implant surface area in the posterior regions primarily by focusing on diameter. However, this increases surface area by only 30% for conventional thread designs despite the fact that forces increase by > 300% in the posterior regions. A change in implant diameter and thread design may increase surface area by > 300%. Such increases in surface area may decrease stresses to the crestal bone regions and reduce both crestal bone loss and early loading implant failure.

The contour of the residual ridge is reduced within 1 year by approximately 25% in width after the extraction of a natural tooth. The augmentation of a tooth socket after an extraction decreases the loss of available bone width for an endosteal implant. Grafting at the same time as the extraction has benefits from both a patient and doctor perspective. However, primary closure is more difficult, and may require the facial keratinized gingiva to be undermined and approximated on the crest of the ridge, or the use of membranes, which are exposed during the soft tissue healing. The modified socket seal surgery uses a technique described by Landsberg and couples his procedure with autologous bone harvested from the maxillary tuberosity. As a result, the tooth extraction socket may be augmented with autologous bone and connective tissue with a simplified approach at the same time as the extraction of a tooth.

When tooth extraction is required, a provisional restoration may be utilized as an interim prosthesis during bone graft and implant healing. The selection of provisional replacement of the anterior teeth following extraction may have a direct influence on the success of the definitive tooth replacement. This article describes a technique for using the extracted tooth or a denture tooth as an interim prosthesis during bone graft and implant healing. This method of provisionalization offers several advantages, including no adjacent tooth preparation, natural appearance, and retention of the papillae.

Implant success is as difficult to describe as the success criteria required for a tooth. A range from health to disease exists in both conditions. The primary criteria for assessing implant quality are pain and mobility. The presence of either one greatly compromises the implant, and removal is usually indicated. Probing depths may be related to the presence of local disease or pre-existing tissue thickness before the implant was inserted. An increasing probing depth is more diagnostic and signifies bone loss, gingival hyperplasia or hypertrophy. Bone loss is usually evaluated best with probing rather than with radiographs. The most common cause of bone loss during the first few years of function are exaggerated factors of stress. The bleeding index is easily observed and indicates inflammation of the gingiva. However, implant health status is not as related to sulcular inflammation as would be the case for a natural tooth. Implant failure is easier to describe and may consist of a variety of factors. Any pain, vertical mobility, uncontrolled progressive bone loss, and/or generalized periradiolucency warrant implant removal. Implant quality factors were established by James and modified by Misch into an implant quality scale which not only assesses the implant health-disease continuum, but relates treatment and prognosis to the existing conditions.

A system is introduced in which dental implants are specifically designed for containment within four different categories of bone densities. The sizes and the textured surfaces that accompany the gradations of lengths and diameters are standardized for each bone type. A modified thread design focuses on compression of bone rather than on shear, and the geometry of the entire implant body reflects features that are concurrent with a "platform effect." Having been tested by means of finite element analysis and initial animal studies, the results are provided herein for the placement of 364 consecutive implants in five clinical centers on human patients, with surgical survival results of 98.9 percent overall. The initial clinical report of these implants indicates that all bone densities may have similar initial survival rates.