The convergence of regenerative medicine and rehabilitation: federal perspectives.

Regenerative rehabilitation is the synergistic integration of principles and approaches from the regenerative medicine and rehabilitation fields, with the goal of optimizing form and function as well as patient independence. Regenerative medicine approaches for repairing or replacing damaged tissue or whole organs vary from utilizing cells (e.g., stem cells), to biologics (e.g., growth factors), to approaches using biomaterials and scaffolds, to any combination of these. While regenerative medicine offers tremendous clinical promise, regenerative rehabilitation offers the opportunity to positively influence regenerative medicine by inclusion of principles from rehabilitation sciences. Regenerative medicine by itself may not be sufficient to ensure successful translation into improving the function of those in the most need. Conversely, with a better understanding of regenerative medicine principals, rehabilitation researchers can better tailor rehabilitation efforts to accommodate and maximize the potential of regenerative approaches. Regenerative rehabilitative strategies can include activity-mediated plasticity, exercise dosing, electrical stimulation, and nutritional enhancers. Critical barriers in translating regenerative medicine techniques into humans may be difficult to overcome if preclinical studies do not consider outcomes that typically fall in the rehabilitation research domain, such as function, range of motion, sensation, and pain. The authors believe that encouraging clinicians and researchers from multiple disciplines to work collaboratively and synergistically will maximize restoration of function and quality of life for disabled and/or injured patients, including U.S. Veterans and Military Service Members (MSMs). Federal Government agencies have been investing in research and clinical care efforts focused on regenerative medicine (NIH, NSF, VA, and DoD), rehabilitation sciences (VA, NIH, NSF, DoD) and, more recently, regenerative rehabilitation (NIH and VA). As science advances and technology matures, researchers need to consider the integrative approach of regenerative rehabilitation to maximize the outcome to fully restore the function of patients.

The periodontal-medical risk relationship.

The evidence of a periodontal-medical risk warrants serious consideration. As dentists increase their knowledge about the link between periodontal disease and other systemic diseases, they will be able to prevent periodontal disease in more patients as well as develop better treatments for the disease. It is important for physicians and dentists to improve their collaboration to provide better patient care. Physician awareness of the increased risk for dental complications in certain patients will benefit their patients' overall well-being.

Bone grafts and growth and differentiation factors for regenerative therapy: a review.

Guided bone regeneration, tissue grafts, regenerative barrier membranes, and bone substitute materials have been used to restore inadequate hard and soft tissue structures to make them conducive to proper implant placement. Polypeptide growth and development factors (GDFs) have successfully been applied exogenously to periodontal defects to attract preosteoblasts to the site and accelerate their proliferation to stimulate angiogenesis. This article provides an overview of current modalities for restoring lost bone and soft tissue during the treatment of periodontal disease.

The relationship between periodontal disease and systemic conditions.

In this year's report of the United States Surgeon General on oral health in America, two major themes evolved: 1) oral health means much more than healthy teeth, and 2) oral health is integral to general health. This article describes how oral diseases, in particular periodontal diseases, are associated with other health problems, including cardiovascular disease, diabetes mellitus, complications of pregnancies, and osteoporosis.

A prospective multicenter clinical trial comparing one- and two-stage titanium screw-shaped fixtures with one-stage plasma-sprayed solid-screw fixtures.

BACKGROUND: Brånemark fixtures were originally placed in two stages, whereas titanium plasma-sprayed (TPS) solid-screws are placed in one stage. Long-term survival rates for both types of implants are excellent. Excellent survival rates have also been reported for machined screw-shaped (MS) titanium implants placed in one stage. A small number of studies have compared different implant systems and methods of implant placement. PURPOSE: The purpose of this study is to report clinical outcomes from a prospective longitudinal, multicenter study comparing Brånemark MS fixtures (Nobel Biocare, Yorba Linda, California, USA) placed in either one or two stages with a one-stage TPS system (ITI Straumann, Waldenburg, Switzerland). METHODS: A protocol was designed to compare implant survival rates, changes in crestal bone for titanium MS fixtures placed in one and two stages, and plasma-sprayed solid-screw fixtures placed in one surgical stage. Twenty-nine patients ranging in age from 24 to 82 years received MS fixtures in one stage. The average age for males was 58 years (n = 11), whereas the ages for females (n = 18) ranged from 15 to 84 years (average 58 years). Twenty-nine patients received machined titanium fixtures placed in two stages. There were 20 females ranging in age from 23 to 74 years (average 54 years) and 9 females ranging from 24 to 74 years (average 46 years). Twenty-five patients received TPS fixtures. There were 15 males, ranging in age from 57 to 79 (average 70), and 10 females, ranging in age from 40 to 83 years (average 62 years). Bone quality and quantity were determined from radiographs and during site preparation. Patient age, sex, location of implant placement according to jaw, length of fixtures, and number of lost fixtures were entered onto computer code sheets and continuously entered into a locked computer system. For one- and two-stage MS fixtures, nonstandardized periapical radiographs were taken at abutment connection and follow-up. Solid screws were x-rayed at prostheses connection and follow-up. The average time between implant restoration and radiographic follow-up was 15 months. The x-rays were scanned into a computer, and a program designed to measure radiographs was used to determine changes in crestal bone. Measurements for one- and two-stage MS fixtures were made from the top of the implant shoulder to the first bone to implant contact mesial and distally. Plasma-sprayed screws were measured from the bottom of the implant to the coronal most bone to implant contacts mesial and distally. Mesial-distal radiographic measurements were averaged and changes were compared using the t-test for related samples. RESULTS: This report presents data from the 2- to 3-year follow-up examinations. Twenty-nine patients received 80 one-stage MS fixtures. Between 0 and 1 year, two fixtures were lost, resulting in a 97.5% cumulative survival rate (CSR). The CSR remained unchanged through the 2- to 3-year follow-up. Twenty-eight patients received 78 two-stage MS fixtures. One implant was lost prior to loading and two were lost between 0- and 1-year follow-up, yielding a 96.2% CSR at the end of 1 year. The CSR remained unchanged through the 2- to 3-year follow-up. Twenty-three patients received 78 solid-screw plasma-sprayed screws. One implant was lost prior to loading and one between the 0- to 1-year follow-up, accounting for a 97.4% CSR at the 2- to 3-year follow-up. Changes in bone crest measurements for one-stage titanium threaded fixtures were insignificant (-0.11 mm, p = .08, maxillary; 0.07 mm, p = .42, mandibular). For two-stage MS fixtures, crestal bone loss was insignificant in maxillae (-0.16 mm, p = .92) and significant in mandibles (-0.43 mm, p = .000). There was significant bone loss for TPS implants in maxillae and mandibles (maxillae, 1.31 mm, p = .04; mandibles, 0.98 mm, p = .000). CONCLUSIONS: Cumulative survival rates for MS fixtures placed in one and two stages as well as one-stage TPS screws up to the 2- to 3-year follow-up examination were similar, indicating excellent clinical results. Radiographic measurements for changes in crestal bone loss were clinically insignificant for fixtures placed in one stage. For two-stage fixtures, maxillary changes were insignificant, whereas mandibular bone loss was statistically significant but clinically insignificant. Changes in crestal bone loss for TPS implants were statistically significant.

The psychosocial context of Black women's health.

Researchers have demonstrated that Black women exhibit a disproportionate risk of ill health. We examined the relationship between psychosocial factors, including economic status, race-based social inequality, gender-based violence, and the health status of 323 Black women between the ages of 18 and 65. Black women from a community sample completed a health survey with open-ended responses. Results indicated that women in lower economic groups are more likely to be treated for allergies (p = < .05) and pelvic inflammatory disease (PID; p = < .01). Women who experienced increased incidents of race-based social inequality received more medical treatments for yeast infections, pregnancy-related problems, allergies, and PID. Those with histories of physical, psychological, and early sexual abuse are more likely to be treated for depression, allergies, yeast infections, and hypertension. In addition, qualitative data examined the process in which economic, race-based social inequality, and gender-based violence contributed to the ill health of Black women. The implications of these findings suggest that understanding the psychosocial context is essential for appropriate clinical practice. Additionally, future research should conceptualize health as a complex interaction of psychosocial risks that have a profound effect on the health status of Black women.

Biologic width and its relation to periodontal biotypes.

Although average measurements of the biologic zone do not necessarily reflect any one clinical situation, they do establish a basis upon which clinical decisions can be made. Clinical impressions, human autopsy material, and animal studies support the concept of a biologic width. Impingement on the attachment in a susceptible host has shown adverse reactions, including gingival inflammation and alveolar bone loss. The concept is clinically important in determining the extent of osseous surgery necessary in the exposure of sound tooth structure. If the implant-abutment interface is considered to be similar to a subgingival crown margin, its importance in relation to peri-implant inflammatory disease is readily apparent. In the presence of inflammation, it is likely that epithelial migration would occur to a level apical to that source. Clinical observations indicate that, once the biologic attachment is invaded around the implant, the gingival reactions are similar to those found around natural teeth, whether the tissue is of the thick flat or thin scalloped type.

Biologic and clinical considerations for autografts and allografts in periodontal regeneration therapy.

Although complete periodontal regeneration is unpredictable with any regenerative therapy currently used, periodontal bone grafts show strong potential. A large body of clinical evidence clearly indicates that grafts consistently lead to better bone fill than nongrafted controls. Regardless of which material is used, the average bone fill is 3 mm, or about 60% defect fill according to reported studies. In addition, histologic analyses now show conclusively that regenerative treatment with bone grafting leads to some degree of regenerated bone, cementum, and periodontal ligament. Although bone grafts and other periodontal treatments have improved clinicians' ability to promote osteogeneration, the outcomes are still somewhat unpredictable. Part of the problem is that it is still unclear how periodontal disease affects the supporting bone's regenerative potential and what specific biologic factors are involved. In recent years, however, clinicians have begun to learn much more about how periodontal regeneration works on a cellular and molecular level. This is a key step to developing strategies and materials that allow clinicians to promote periodontal regeneration predictably. Since its introduction during the last decade, GTR has been an invaluable addition to the armamentarium, as has the recognized importance of early wound stability. As more is learned about the biologic process of periodontal regeneration, new materials and techniques, such as growth factors, absorbable membranes, and new graft materials, are expected to make the task of periodontal regeneration even more predictable. It is likely that some combination of techniques may eventually prove to yield the best results.

Teeth or implants: a 1990s dilemma.

Using endosseous implants to replace missing teeth is a highly predictable process when the precepts defined by Brånemark are followed. The question of whether or not to extract periodontally compromised teeth, however, remains controversial. This article presents a case report illustrating some of the concerns involved when treating a patient with a combination of natural teeth and implants, and proposes several compelling questions regarding the treatment decisions made in this case.

Outcome failures of endosseous implants from a clinical training center.

In an effort to provide realistic clinical information from a "real-world" environment, the present retrospective study was undertaken to assess outcome failures after implant placement in a dental school clinical training center. A database was kept of the clinical information and was analyzed according to established parameters for implant outcomes. The demographics showed that over a period of 6 years, 80 different operators with a wide range of clinical experience had inserted 1,263 implants in a diverse patient pool of 380 individuals. Analysis of the outcomes showed a cumulative survival rate of 91.3%. The time of explantation, the type, size, and location of implants lost, and failure rates in smoking patients were also analyzed. The results indicated that the use of implants by operators with different levels of experience did not affect favorable outcomes.

Treatment planning and site development for the implant-assisted periodontal reconstruction.

Implants can be used to recreate an edentulous dentition that is esthetic, comfortable, and functional by augmenting the total surface area of load carrying abutments. Traditionally, implants were placed in areas of the mouth where adequate amounts of bone were present. Today, clinicians are strategically planning and developing implant sites to optimize oral health. This article will describe methods of treatment planning and site development for the reconstruction of the implant-assisted periodontal restoration.

Immediate loading of bilaterally splinted titanium root-form implants in fixed prosthodontics--a technique reexamined: two case reports.

A load-free healing period has been advocated as a prerequisite to achieving osseointegration. This article reports two cases in which immediate loading of a specially designated additional, or "expendable," set of titanium root-form implants was successfully utilized to support provisional fixed restorations in the maxilla and the mandible. This immediate-loading protocol is suggested as a reliable adjunctive therapeutic modality for offering implant patients access to fixed interim restorations during the healing phase of the primary fixtures. Another advantage of this approach is that it provides protection from potential transmucosal overload of the primary implants as well as any sites undergoing osseous regenerative procedures.

The relationship of beta-glucuronidase activity in crevicular fluid to probing attachment loss in patients with adult periodontitis. Findings from a multicenter study.

Analysis of gingival crevicular fluid (GCF) offers a non-invasive means of studying the host response in periodontal disease, and may provide an early indication of the patient at risk for active periodontitis. A number of host markers have been studied for their relationship to disease activity (probing attachment loss or PAL). GCF levels of the acid glycohydrolase beta-glucuronidase (beta G), a marker of primary granule release from polymorphonuclear leukocytes (PMN), have been shown to identify patients with periodontitis at risk for additional PAL. In this multicenter trial, we evaluated (a) the short-term effect of conservative periodontal therapy on beta G activity in GCF, and (b) the relationship of persistently elevated beta G activity to PAL in patients who were monitored for 6 months. The study population included a total of 140 patients with chronic adult periodontitis. 130 patients were on a regular recall schedule, and 10 were previously untreated. After collection of baseline clinical data at all sites, and analysis of beta G in GCF from one site (mesiobuccal) per tooth, the patients received a scaling and prophylaxis. Two weeks later patients were seen for collection of GCF. If elevated enzyme activity was found at 2 weeks, the patients were seen at 3 months for a clinical exam and GCF collection. Clinical parameters were collected from all patients at 6 months. Therapy tended to reduce beta G activity in GCF.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship of beta-glucuronidase activity in crevicular fluid to clinical parameters of periodontal disease. Findings from a multicenter study.

Previous reports have suggested that persistently elevated levels of the acidic glycohydrolase beta-glucuronidase (beta G) in gingival crevicular fluid (GCF) can identify patients with chronic adult periodontitis who are at risk for future probing attachment loss (PAL). To comprehensively study beta G activity in GCF, a multicenter trial examining the relationship of the enzyme in GCF to traditional clinical parameters of periodontal disease and PAL was conducted. In this report, the baseline data was used to evaluate the relationship of beta G activity in GCF to traditional parameters of periodontal disease. The study group included 130 patients who had been treated for periodontal disease and were on a regular recall schedule, and 10 patients with chronic adult periodontitis who had never received treatment. Upon entering the longitudinal trial, the patients were examined, and a standardized 30-s GCF sample was collected from the mesiobuccal crevice of all study teeth. As a control, GCF samples and clinical data were collected from 62 patients with a healthy periodontium or mild inflammatory gingivitis without loss of probing attachment. At baseline, beta G activity for the periodontitis patients ranged from 0 to 1704 Units (U), with a median of 32 U. beta G could not be detected in 0.2% of samples (activity < or = 2.0 U). The 90% cumulative relative frequency was 139 U. For the healthy/gingivitis subjects beta G activity ranged from 0 to 504 U, with a median of 22 U. Enzyme was not detectable in 0.4% of samples. Only 0.9% of samples contained greater than 139 U. beta G activity in GCF was not related to gender or age. For the periodontitis patients, elevated enzyme activity (> or = 140 U) was most often associated with molar teeth, followed by maxillary bicuspids. Maxillary central incisors, and mandibular central and lateral incisors displayed the lowest frequency of elevated enzyme activity. The relationship of beta G activity to the traditional parameters of probing depth and bleeding on probing was assessed. For shallow sites (1.0-1.5 mm, 2.0-2.5 mm probing depth), the large majority of GCF samples contained low enzyme activity (90% of samples < 50 U). Descriptive indicators demonstrated a trend of increased beta G activity with increased probing depth. The median beta G activity shifted from 15 U for the shallowest sites (1.0-1.5 mm) to 127 U for the deepest sites (5-8 mm). However, this was due to a broadening of the distribution rather than representing a shift in the distribution profile.(ABSTRACT TRUNCATED AT 400 WORDS)