Exploring Dentists’ Interest in the Long-term Success of Dental Implants: A Quantitative Analysis

The status of implant training in oral and maxillofacial surgery residency programs

The study was conducted to evaluate the effect of mineralized freeze-dried bone allograft (FDBA), alone or in combination with growth factors in extraction sockets, on subjective assessment of bone quality during implant placement. Forty-one patients whose treatment plan involved extraction of anterior or premolar teeth were randomized into four groups: Group 1, collagen plug (control); Group 2, FDBA/β-tricalcium phosphate (β-TCP)/collagen plug; Group 3, FDBA/β-TCP/platelet-rich plasma (PRP)/collagen plug; Group 4, FDBA/β-TCP/recombinant human platelet-derived growth factor BB (rhPDGF-BB)/collagen plug. After 8 weeks of healing, implants were placed. The clinicians assessed bone quality according to the Misch classification. A benchtop calibration exercise test was conducted to evaluate agreement and accuracy of operators in recognizing different bone qualities. Differences were analyzed using one-way analysis of variance (ANOVA) or chi-square tests for continuous and categorical data. Pairwise comparisons were tested using least squares means (LS means). Spearman correlation coefficients were used to evaluate the relationship of bone growth with potential confounders. P < .05 was considered statistically significant. A simple (not weighted) kappa statistic was used to assess the agreement between raters. To assess accuracy in identifying bone quality, a chi-square test was used to compare the percent correct for each rater. The benchtop calibration exercise test demonstrated agreement among clinicians (0.75 and 0.92 between raters 1 and 2 and raters 1 and 3, respectively). Raters were more likely to identify the correct bone quality (P > .05). Inclusion of bone grafting is associated with a shift from D4 quality to D3 quality bone. Inclusion of PRP in bone grafting eliminates the incidence of D4 bone, establishing D3 and D2 quality bone as prevalent (56% vs. 42%, respectively). Inclusion of rhPDGF-BB and β-TCP in combination with the bone grafting has the same effect, although D2 quality is less prevalent. When compared to sockets grafted with FDBA/β-TCP/collagen plug alone, the sockets with growth factors demonstrated fewer residual bone graft particles. (1) Inclusion of bone grafting enhanced bone quality as assessed during implant placement. (2) Overall inclusion of PRP and rhPDGF-BB enhanced subjective bone quality, eliminating incidence of D4 quality in human extraction sockets. (3) The use of PRP or rhPDGF-BB may enhance healing within extraction sockets and decrease the healing time prior to dental implant placement.

Bone strength is determined not only by bone quantity [bone mineral density (BMD)] but also by bone quality, including matrix composition, collagen fiber arrangement, microarchitecture, geometry, mineralization, and bone turnover, among others. These aspects influence elasticity, the load-bearing and repair capacity of bone, and microcrack propagation and are thus key to fractures and their avoidance. In chronic kidney disease (CKD)-associated osteoporosis, factors traditionally associated with a lower bone mass (advanced age or hypogonadism) often coexist with non-traditional factors specific to CKD (uremic toxins or renal osteodystrophy, among others), which will have an impact on bone quality. The gold standard for measuring BMD is dual-energy X-ray absorptiometry, which is widely accepted in the general population and is also capable of predicting fracture risk in CKD. Nevertheless, a significant number of fractures occur in the absence of densitometric World Health Organization (WHO) criteria for osteoporosis, suggesting that methods that also evaluate bone quality need to be considered in order to achieve a comprehensive assessment of fracture risk. The techniques for measuring bone quality are limited by their high cost or invasive nature, which has prevented their implementation in clinical practice. A bone biopsy, high-resolution peripheral quantitative computed tomography, and impact microindentation are some of the methods established to assess bone quality. Herein, we review the current evidence in the literature with the aim of exploring the factors that affect both bone quality and bone quantity in CKD and describing available techniques to assess them.

Fig. 1: Adele L. Boskey, PhD, is shown.Fig. 2: Eve Donnelly, PhD, is shown.Fig. 3: J. Gregory Kinnett, MD, is shown.The term “bone quality” is frequently used by clinicians, basic scientists, and engineers. However, do they mean the same thing? In this symposium, we asked the authors what they meant by “bone quality,” and as the reader will discover, there are many aspects of bone quality that vary in importance and scope with the person providing the definition. In recent years, numerous reviews have explored and described bone quality (eg, [2-25, 29]) and some have discussed therapies for fragility fractures [13], but none has emphasized the transition from the bench to the bedside (and the operating room). In fact, the majority of these reviews of bone quality are either engineering or basic bone biology articles [3-6, 10, 11, 16], including imaging techniques [3, 8, 12, 17, 20, 25], or papers on how to treat osteoporosis [5, 7, 9, 15, 18, 19, 21, 23, 24]. Here too we review those topics, providing recent research data from leaders in the field. This symposium reviews and makes suggestions for appropriate management of individuals with impaired bone quality because the orthopaedic surgeon sees cases where the quality of the bone is abnormal, whether in patients with osteoporosis, osteopetrosis, cancer [14], or a metabolic problem, such as diabetes [22], kidney disease [29], or rheumatoid arthritis, and because little guidance is available on pre- and postsurgical management of these cases. We, the guest editors for this symposium, hope the material we provide will serve as a convenient and long-lasting reference for what bone quality is, how it can be measured, how it can be manipulated, and how the orthopaedic clinician should think about it when planning surgery and postoperative care or clinical research studies. The symposium starts with an overview of the different methods used to measure bone quality. This is followed by papers elaborating on the information that can be learned by selected examples of these techniques. The first paper by Dr. Donnelly should thus be used as a guide for selecting which methodology-based papers need to be read in more depth. After describing methods, papers are presented on diseases, including but not limited to osteoporosis, in which bone quality is altered, reviewing diagnostic methods and therapeutic management of patients with “altered bone quality.” Finally, we conclude with papers on the posttreatment management of these patients. Unfortunately, it was not possible to provide papers on all the new methods for characterizing bone quality, such as phosphorus-31 nuclear magnetic resonance [1, 27, 28] nor was it possible to provide descriptions of all of the newer therapies in preclinical and clinical trials aimed at preventing fracture reduction. Nonetheless, we hope the symposium will provide guidance for surgeons dealing with patients with altered bone quality and also will identify areas where additional investigations are needed. It is also hoped the clinician reader will appreciate how techniques such as Raman imaging of bone might soon be extended to clinical practice, bridging the gap between the laboratory and the clinic. The invited contributors were asked to define bone quality from their perspective and review the field, including, where applicable, providing examples from their own unpublished data. Because of this model, there is some redundancy in the papers, but we have done our best to ensure this does not happen too frequently. The guest editors would like to thank all the authors who contributed to this symposium and all the reviewers who provided input on these articles. We hope the readers will find this both useful and informative and they will consider the many qualities of bone when they are treating their patients and trying to explain unexpected bone properties.

The integration and long-term success of dental implants exploit the unique biology of the oral cavity, which allows for osseous incorporation of a biomaterial and its long-term health within a bacteria-laden oral milieu.1 The delicate balance of defense and repair mechanisms underlying this unique environment may be challenged by various factors that can act both locally and/or systemically, thereby increasing the risk of implant loss and jeopardizing the long-term success of inserted implants. Local risk factors that are present in the oral cavity and systemic risk factors that have the potential to affect oral health on a systemic level can compromise implant treatment at all stages of treatment delivery by: (a) complicating surgical procedures and other invasive measures required during treatment; (b) compromising the process of tissue healing following implant insertion/increasing the risk of wound infection; and (c) contributing to the deterioration of long-term peri-implant health and tissue stability (Table 1). Reduced bone healing Reduced implant stability Reduced bone remodeling Reduced angiogenesis Reduced bone regeneration Acquired immunosuppression Hypovascularity Iatrogenic immunosuppression Reduced tissue regeneration Hypovascularity hypoxia Leukocyte dysfunction Conditions that interfere with invasive procedures, which include poor general health status (https://www.asahq.org/resources/clinical-information/asa-physical-status-classification-system) as a result of severe systemic disease, may impact upon implant surgery, healing, and maintenance. These are mostly cardiovascular conditions that can place the patient at high risk during surgery, irrespective of the nature of the intervention. Bleeding disorders, which may be innate or acquired, as well as attributable to the use of anticoagulants, may also complicate invasive measures. While the former are considered to be relatively rare, the latter may have a significant impact on daily implant treatment in an aging population. All these conditions can also have a negative impact on long-term peri-implant health and maintenance of peri-implant tissues as a result of compromised vascularity, as well as alterations in the immune defense or repair capacity of peri-implant tissues. The increasing patient demand for implant-based treatments in conjunction with a demographic shift of the patient population has resulted in a growing body of literature dealing with an increasing number of patients presenting with medical conditions. A recent cross-sectional analysis indicated that almost 90% of patients aged > 65 years were taking medication for underlying systemic diseases, which could jeopardize implant success.2 The advent of new treatment modalities, such as antiresorptive drugs or monoclonal antibody therapies, adds to the number of potential risk factors,3 leading to an increasing challenge for the provision of implant-based treatments in the future. The aim of this narrative review was therefore to analyze the importance of systemic and local conditions as risk factors for implant loss by critically evaluating the available evidence. During evaluation of the available literature, it was obvious that the term "implant loss" was used to a much lesser degree than "implant failure." Very few reports clearly defined implant failure as implant loss, but the context in which this term has historically been used indicates that implant failure was synonymous for implant loss. It is only in the last decade or so that definitions of implant failure have been published, and not until the 2017 World Workshop on Periodontal and Peri-Implant Disease Classification was an international definition agreed upon.4 One of the major reasons for implant loss is the progressive loss of peri-implant bone support. Therefore, marginal bone loss was also included in the analysis. As progressive crestal bone loss around implants in the absence of clinical signs of soft tissue inflammation is rare,5 reported radiographic bone loss was considered in conjunction with clinical peri-implant parameters (where provided) in the individual reports in order to assess the prognostic relevance of the findings. The effect of cardiovascular conditions on implant treatment has been mostly analyzed in cross-sectional cohort studies. In these reports, 15.6%-37%6-8 of patients were affected by cardiovascular diseases. Two recent multivariate analyses of large cohorts consisting of > 6300 and > 22 000 patients did not identify cardiovascular conditions as significant risk factors for implant loss6 or peri-implant pathology.9 This is in line with other cross-sectional studies of smaller cohorts.10-13 Cardiovascular conditions may, however, be associated with the maintenance of long-term peri-implant tissue health. Patients with diseased implants have shown a higher likelihood of cardiovascular comorbidity,8 and a recent prospective study of 44 patients with fixed mandibular prostheses demonstrated an association between cardiovascular disease and increased radiographic peri-implant bone loss.14 The available evidence currently suggests that cardiovascular conditions are not a major risk factor for implant loss. Although the radiographic bone loss reported had not been classified as progressive, cardiovascular disease should be taken into account in maintenance protocols as a potential comorbidity15 that may affect long-term peri-implant tissue health. Bleeding disorders can be innate, such as hemophilia A/B and von Willebrand–Jürgens Syndrome, or acquired during end stage liver disease, with subsequent deterioration of coagulation factors and platelet counts. The placement of implants in patients with hemophilia is rarely documented in case reports.16, 17 In contrast to this, patients with iatrogenic bleeding disorders as a result of anticoagulation therapy have been studied more frequently. Depending on the underlying disease, anticoagulation therapy may encompass antiplatelet drugs, vitamin K antagonists, or direct oral anticoagulants. There is widespread agreement that anticoagulation therapy with antiplatelet drugs or vitamin K antagonists should not be discontinued for dental surgical procedures, as long as a single drug is used and the level of activity is within the therapeutic range (international normalized ratio 2.5-3.0).18, 19 Some uncertainty exists about the management of patients using direct oral anticoagulants, but it is assumed that no interruption of therapy is required; consulting with the hematologist responsible for the patient's care is always advisable.20 Implant surgery in patients undergoing anticoagulation therapy has been reported in a number of controlled clinical studies, albeit consisting of rather small cohorts.21-24 Follow-up included an immediate postoperative period of 8-10 days. All the authors agreed that implants could be safely placed in patients with anticoagulation therapy without interruption of medication of vitamin K antagonists or direct oral anticoagulants. An exception to this may be dual anticoagulation therapy using two antiplatelet drugs (acetylsalicylic acid and clopidogrel), as is commonly employed following stenting of the coronary arteries. In these cases, postoperative morbidity may occur as a result of the increased risk of postoperative bleeding (Figure 1). Implant surgery should therefore be postponed until dual antiplatelet therapy has returned to single antiplatelet drug use. Depending on the type of stent used, this period may vary from 6 weeks to 6 months. To date, no information is available on implant complications arising in anticoagulated patients beyond the immediate period of surgical wound healing. The management of secondary interventions for soft tissue management or peri-implant diseases has not yet been reported on, but may have an impact on the long-term prognosis of implants, and should be taken into consideration when implants are planned for patients with anticoagulation management. Moreover, it should be noted that the necessity for anticoagulation therapy is commonly an underlying cardiovascular condition that needs to be explored and may require additional action. If anticoagulation therapy is used because of a cardiac condition associated with an increased risk for infective endocarditis, antibiotic prophylaxis is required.25 The necessity for antibiotic prophylaxis has been questioned based on a low risk of bacteremia during implant insertion,26 but adherence to current updates of national guidelines is strongly recommended.27, 28 Osteoporosis is characterized by a loss of structural quality of cancellous bone and a reduction in cortical bone thickness resulting in an overall deterioration of bone density. Approximately 48% of women and 15% of men aged ≥ 75 years are known to be affected.29 Primary osteoporosis can arise because of the loss of osteoanabolic effects of sex hormones (type I) in postmenopausal women (and some 10 years later in men), or because of age-related changes in general metabolism (type II). Osteoporosis may also arise secondary to endocrine diseases (eg, Cushing Syndrome, parathyroid hormone excess) or as a result of medication (eg, corticosteroids). Commonly, the diagnosis is derived from dual energy X-ray absorptiometry of the spine and/or the proximal femur. Dual energy X-ray absorptiometry scans provide a T-score that expresses the deviation of bone mineral density of the patient in standard deviations from the average value of healthy young adults. A T-score of < –2.5 is considered to be indicative of osteoporosis. Osteoporosis has been a concern in implant dentistry from an early stage in the development of the field.30-32 A number of papers have addressed the question of whether reduced skeletal bone density is associated with inferior bone quality in the maxilla or mandible. Subjectively, perceived jaw bone quality did not correlate with documented dual energy X-ray absorptiometry scores.33 Moreover, bone next to implants retrieved from osteoporotic patients did not exhibit a reduced number of bone cells or bone-to-implant contact.34 To identify individuals with reduced skeletal bone density, panoramic indices such as the mandibular cortex width,35 panoramic mandibular index,36 and the Klemetti index37 have been developed. A recent review reported these indices as useful in intercepting patients with reduced bone mineral density (T-score < 1), but did not recommend them to intercept patients with osteopenia/osteoporosis.38 Moreover, a systematic review examining the association between objective measures of jaw bone quality and skeletal bone mineral density was unable to clarify whether skeletal osteoporosis is associated with osteoporosis in the jaw bones.39 The role of osteoporosis in the success of implant treatment and the stability of marginal bone has been evaluated in a number of studies. Recent systematic reviews have found no difference in implant survival rates between patients with and without osteoporosis (risk ratio 1.9, 95% confidence interval 0.93-2.08, P = .11),40 or identified a direct but insignificant effect of osteoporosis on dental implant loss (risk ratio 1.09, 95% confidence interval 0.79-1.52).41 Similarly, earlier reviews and case control studies42-45 did not find evidence for an association between skeletal bone mineral density/osteoporosis and increased implant loss. With regard to peri-implant bone loss, the majority of recent studies (two cross-sectional,46, 47 one prospective,48 and one case control study49) reported no difference in radiographic peri-implant bone loss between patients with and without osteoporosis. Only one cross-sectional study reported significantly increased radiographic loss of marginal bone in osteoporotic patients after 1 year.50 All the patients in this study were part of a maintenance program with low periodontal indices and healthy periodontal conditions. Differences in radiographic bone level changes have been attributed to differences in bone remodeling in osteoporotic patients. The relevance of these findings with regard to long-term implant prognosis remains to be determined. While osteoporosis as such may not play a role in implant failure or loss of peri-implant bone, medications used for osteoporosis therapy may interfere with osseointegration and long-term maintenance of peri-implant health. The drugs prescribed are mostly either bisphosphonates51 or denosumab, a monoclonal antibody against the signaling molecule RANKL that is involved in the recruitment of osteoclasts. Bisphosphonates reduce both the resorptive activity of osteoclasts, as well as the activity of osteoblasts in a dose-dependent manner,52, 53 while denosumab directly reduces osteoclast activity.54 The net effect of the antiresorptive therapy is a decrease in bone turnover and remodeling activity of bone tissues. As remodeling is an essential part of bone regeneration and osseointegration, there has been some concern expressed regarding the capacity of peri-implant bone to incorporate implants inserted under bisphosphonate therapy. Controlled clinical trials have reported implant survival rates of 85.7%-100% in patients taking oral bisphosphonates55, 56 and of 100% for those receiving intravenous bisphosphonates.57 Recent meta-analyses of studies assessing the impact of bisphosphonates on implant treatment concluded that there is insufficient evidence for a negative effect of bisphosphonates on implant survival.58, 59 Besides the effect on implant survival, another aspect of the long-term use of antiresorptive agents is the risk of developing a medication-related necrosis of the jaw.60, 61 Medication-related necrosis of the jaw can be triggered by intra-oral surgical interventions and by bacterial invasion from odontogenic infectious lesions,62 as well as through pressure ulcers resulting from poorly fitting removable dentures.63 Triggering of the onset of medication-related necrosis of the jaw during the insertion of dental implants or through the occurrence of peri-implant infections during follow-up under antiresorptive medication is therefore a significant concern,64-66 and most often requires rather invasive measures for management (Figure 2A-G). The prevalence of medication-related necrosis of the jaw has been considered to depend in part on the route and frequency of bisphosphonate administration, with oral bisphosphonates presenting a lower risk for medication-related necrosis of the jaw than intravenous bisphosphonates. More recent reviews suggest that it is not the route of administration but the dosage of antiresorptive medication that affects the prevalence of medication-related necrosis of the jaw.59 The evidence reported for the occurrence of implant-related medication-related necrosis of the jaw under therapy with either bisphosphonates or denosumab is largely based on case reports64, 67-75 or retrospective case series.63, 76-84 In these reports, the number of cases reported for implant-related medication-related necrosis of the jaw in patients taking oral bisphosphonates is almost as high (n = 74) as in patients receiving intravenous bisphosphonates or denosumab (n = 84), suggesting that it is not the route of administration that is critical for the occurrence of implant-related medication-related necrosis of the jaw. Conversely, a number of case reports and case series reporting on implant treatment with concurrent oral bisphosphonate therapy did not find any cases of medication-related necrosis of the jaw in the patients studied.55, 65, 85-95 The existing level of evidence for an association between implant treatment and the occurrence of medication-related necrosis of the jaw under antiresorptive therapy remains low and needs to be substantiated by appropriately designed randomized controlled trials. Nevertheless, the overall number of reported cases of implant-associated medication-related necrosis of the jaw suggests that antiresorptive drugs need to be considered as a risk factor96 and explained to patients97 prior to the start of the treatment, as part of collecting informed consent. Despite the potential hazards of implant-associated medication-related necrosis of the jaw, implants can help to reduce the occurrence of medication-related necrosis of the jaw, for example, in edentulous patients under antiresorptive drugs by avoiding pressure ulcers resulting from poorly fitting dentures. Therefore, multiple factors need to be considered to inform a balanced decision on whether a patient with antiresorptive drugs is eligible for implant therapy (Table 2). If the majority of these factors indicate a low to moderate risk, implant therapy may also be a valid option in patients with antiresorptive medication. When oral surgical procedures are planned in patients with antiresorptive medication, antibiotic prophylaxis is recommended.98, 99 The ideal protocol for administration of antibiotics has not yet been defined. A clear recommendation is given for preoperative antibiotic coverage,100 however, the dosage and duration of postoperative continuation of antibiotic therapy remain to be determined. Adherence to national guidelines (if available) for the perioperative management of patients with antiresorptive medication is strongly advised. Diabetes mellitus is characterized by a lack of insulin secretion as a result of the loss of insulin-producing beta cells in the Langerhans islands of the pancreas (type 1) or by impaired insulin function because of the failure of insulin receptors to appropriately respond to the stimulation by insulin in the periphery (type 2). This results in constantly elevated blood glucose levels in people with diabetes, which leads to nonenzymatic glycation of numerous proteins to produce advanced glycation end products. An elevated level of advanced glycation end products leads to increased expression and activation of receptors for advanced glycation end products. These receptors are present on many cells (eg, endothelial cells, smooth muscle cells, fibroblasts, and mesanglial cells). Their activation mediates inflammatory reactions, which are considered to be responsible for alterations in the microvasculature and thereby can account for diabetic angiopathy.101 Interaction of advanced glycation end products with receptors for advanced glycation end products on macrophages is considered to be associated with macrophage dysfunction, leading to impaired wound healing in patients with diabetes.102 Moreover, bone regeneration is directly impaired on a molecular level in people with diabetes.103 Clinically, poor glycemic control has been shown to negatively affect the balance of bone growth factors in the peri-implant fluid during implant healing.104 Deterioration of vascularity in conjunction with a less efficient immunologic defense and a decreased regenerative capacity of peri-implant bone may compromise the success of implant treatment in patients with diabetes considerably. The effect of diabetes on implant success and the maintenance of peri-implant tissues has therefore been subject to research for more than 20 years. Numerous reviews have analyzed this relationship.105-115 A recent meta-analysis of 14 controlled clinical trials demonstrated that the risk ratio for implant loss between patients with and without diabetes was 1.07 (95% confidence interval 0.08-1.44), without a significant difference between the groups (P = .65).109 Failure to show an association between the existence of diabetes and an increased loss of dental implants is in line with previous reviews.20, 108, 113, 114, 116 The level of glycemic control as assessed by HbA1c appears to have no effect on implant survival rates, although patients with diabetes have demonstrated a compromised process of implant integration.104, 113, 117-119 Moreover, a recent consensus paper reported only inconclusive evidence for diabetes as a risk factor for peri-implantitis.5 While implant loss and peri-implant tissue health are obviously not affected by the presence of diabetes as such, management of the disease may play a role in the maintenance of peri-implant tissue health. A number of reports and systematic reviews have shown that patients with diabetes and poor glycemic control have an increased risk of peri-implantitis and associated peri-implant bone loss.76, 112, 120 This has been reported to become obvious at 2 years of follow-up compared with healthy individuals.107 However, when HbA1c is within the physiological range and oral hygiene is appropriate, the levels of inflammation have been shown to be reduced to those of healthy patients.121 The prophylactic use of antibiotics in oral surgical procedures in patients with diabetes is still controversial. Data from the scarcely available clinical studies favor the use of antibiotics but the evidence for their benefit is still low.122 The immune system is an indispensable part of tissue healing and repair. This holds true also for bone tissue, where pro-inflammatory cytokines are critical, not only for triggering regeneration but also for orchestrating subsequent bone remodeling.123 Moreover, both nonspecific and specific immune responses are crucial for the defense against bacterial invasion following surgery, as well as during the period of restoration and long-term usage. Immune deficiency can thus be critical for integration of dental implants and for the maintenance of peri-implant tissue health. Immune deficiency can result from a large number of conditions. With the exception of very rare innate immune defects, immune deficiencies are mostly acquired in nature. The nonspecific immune response can be affected by medications (immunosuppression/chemotherapy) and metabolic diseases (eg, diabetes mellitus), or because of chronic malnutrition. Specific immunity can also be reduced by immunosuppressive medication, as well as by hematological diseases and lymphotropic viruses (eg, HIV). Iatrogenic immunosuppression as a result of medications is probably the most frequent cause of immune deficiency in dental implant patients. A major indication for deliberate suppression of the immune response is organ transplantation. Organ transplant patients are treated with a combination of drugs that aim to reduce the proliferation of T-cells and to decrease the number of antigen-presenting cells to avoid rejection of the transplanted organ. Commonly, a combination of monoclonal antibody therapy, inhibitors of that and drugs with of is During the drug are high to immune after which are reduced for maintenance of interventions should not be planned during the of immune The effect of immunosuppression on the success of implant treatment in organ transplant patients has rarely been indicate that the peri-implant bone in a clinical information from a case series on patients with liver reported 100% success after Moreover, two prospective controlled studies found no significant difference in implant survival rates between organ transplant patients and after 1 and years of results without significant differences between groups have also been reported for clinical peri-implant soft tissue and for the of peri-implant The available evidence remains but suggests that the clinical results of implant treatment are and not significantly affected by immunosuppressive drugs used by organ transplant patients. of diseases in which immunosuppressive medication is used is the of diseases. The most for daily clinical are diseases, Syndrome, and disease, as well as conditions of oral and such as oral and systemic with oral or conditions that may largely cause local while such as or disease, may be of concern because of the systemic immunosuppressive medications immunosuppression in and in disease is by a combination of drugs, such as monoclonal against necrosis and drugs are a of agents that include and which are also used for immunosuppression in organ transplant diseases are characterized by and of clinical leading to a level of treatment during their This should be in when treatment for these patients. many patients have medication, the negative of this with regard to bone such as osteoporosis and decreased bone also be taken into osteoporosis is considered to be present at of ≥ These patients should be explored for receiving antiresorptive medication to avoid the There is very information available regarding patients with receiving dental implants. A retrospective evaluation of patients with an implant success of after The success rates but between patients with only and those with tissue diseases The stability of marginal bone by the medication drugs drugs and corticosteroids). The existence of tissue diseases was associated with a significant in peri-implant bone loss and higher bleeding indices compared with patients with an increased of peri-implant tissues to The of authors when examining a smaller cohort of patients with Moreover, a retrospective analysis of a cohort of patients did not identify as a significant risk factor for implant However, an of and systemic may these patients more to marginal peri-implant thus a maintenance The results available for patients with disease are Two cross-sectional analyses and one evaluation of cohorts of were by the examining early and implant loss and the role of implant the study one of the cross-sectional analyses identified a significant association between disease and implant the other cross-sectional study However, the of this is to as the number of patients in this cohort with disease was not diseases with oral Syndrome, systemic and oral in conjunction with dental implants, have largely been reported at an level for almost In and systemic were subject to early case reports years is considered to be critical for implant survival and not only as a result of medication, but more so because of leading to increased and bleeding as well as a higher frequency of As a result of the oral and patients with are often unable to removable and can benefit significantly from implant The level of evidence for the effect of on the success of implant treatment is Two case series and case reports provide into 17 patients with a of 99 implants, with 10 implants after years of Two recent retrospective cohort studies reported success rates of and soft tissues a higher but insignificant in the of patients with compared with healthy The existing thus suggests that implants in patients with are not significantly compromised by either the underlying disease or medication. The for peri-implant in these patients the elevated around in patients with Syndrome, and needs during is a disease associated with general of tissues resulting in reduced with subsequent with and dental has been reported in conjunction with dental implants on an level in individual and for two cases as

Background/Objectives: Dental implants have emerged as a modern solution for edentulous jaws, showing high success rates. However, the implant’s success often hinges on the patient’s bone quality and quantity, leading to higher failure rates in poor bone sites. To address this issue, short implants have become a viable alternative to traditional approaches like bone sinus lifting. Among these, Bicon® short implants with a plateau design are popular for their increased surface area, offering potential advantages over threaded implants. Despite their promise, the variability in patient-specific bone quality remains a critical factor influencing implant success and bone turnover regulated by bone strains. Excessive strains can lead to bone loss and implant failure according to Frost’s “Mechanostat” theory. To better understand the implant biomechanical environment, numerical simulation (FEA) is invaluable for correlating implant and bone parameters with strain fields in adjacent bone. The goal was to establish key relationships between short implant geometry, bone quality and quantity, and strain levels in the adjacent bone of patient-dependent elasticity to mitigate the risk of implant failure by avoiding pathological strains. Methods: Nine Bicon Integra-CP™ implants were chosen. Using CT scans, three-dimensional models of the posterior maxilla were created in Solidworks 2022 software to represent the most challenging scenario with minimal available bone, and the implant models were positioned in the jaw with the implant apex supported by the sinus cortical bone. Outer dimensions of the maxilla segment models were determined based on a prior convergence test. Implants and abutments were considered as a single unit made of titanium alloy. The bone segments simulated types III/IV bone by different cancellous bone elasticities and by variable cortical bone elasticity moduli selected based on an experimental data range. Both implants and bone were treated as linearly elastic and isotropic materials. Boundary conditions were restraining the disto-mesial and cranial surfaces of the bone segments. The bone–implant assemblies were subjected to oblique loads, and the bone’s first principal strain fields were analyzed. Maximum strain values were compared with the “minimum effective strain pathological” threshold of 3000 microstrain to assess the implant prognosis. Results: Physiological strains ranging from 490 to 3000 microstrain were observed in the crestal cortical bone, with no excessive strains detected at the implant neck area across different implant dimensions and cortical bone elasticity. In cancellous bone, maximum strains were observed at the first fin tip and were influenced by the implant diameter and length, as well as bone quality and cortical bone elasticity. In the spectrum of modeled bone elasticity and implant dimensions, increasing implant diameter from 4.5 to 6.0 mm resulted in a reduction in maximum strains by 34% to 52%, depending on bone type and cortical bone elasticity. Similarly, increasing implant length from 5.0 to 8.0 mm led to a reduction in maximum strains by 15% to 37%. Additionally, a two-fold reduction in cancellous bone elasticity modulus (type IV vs. III) corresponded to an increase in maximum strains by 16% to 59%. Also, maximum strains increased by 86% to 129% due to a decrease in patient-dependent cortical bone elasticity from the softest to the most rigid bone. Conclusions: The findings have practical implications for dental practitioners planning short finned implants in the posterior maxilla. In cases where the quality of cortical bone is uncertain and bone height is insufficient, wider 6.0 mm diameter implants should be preferred to mitigate the risk of pathological strains. Further investigations of cortical bone architecture and elasticity in the posterior maxilla are recommended to develop comprehensive clinical recommendations considering bone volume and quality limitations. Such research can potentially enable the placement of narrower implants in cases of insufficient bone.

BackgroundTo explore the effects of topographical modification of titanium substrates at submicron level by oxalic acid treatment on bone quality and quantity around dental implants in rabbit tibiae.MethodsA total of 60 blasted CP-grade IV titanium dental implants were used. Twenty-eight control implant surfaces were treated with a mixture of HCl/H2SO4, whereas 28 other test implant surfaces were treated with oxalic acid following HCl/H2SO4 treatment. Two randomly selected sets of control or test implants were placed in randomly selected proximal tibiae of 14 female Japanese white rabbits. Euthanasia was performed 4 and 8 weeks post-implant placement. Bone to implant contact (BIC), bone area fraction (BAF), ratios of mature and immature bone to total bone, and the amount and types of collagen fibers were evaluated quantitatively. Two control and two test implants were used to analyze surface characteristics.ResultsTreatment by oxalic acid significantly decreased Sa and increased Ra of test implant surfaces. BIC in test implants was increased without alteration of BAF and collagen contents at 4 and 8 weeks after implant placement when compared with control implants. The ratios of immature and mature bone to total bone differed significantly between groups at 4 weeks post-implantation. Treatment by oxalic acid increased type I collagen and decreased type III collagen in bone matrices around test implants when compared with control implants at 8 weeks after implant placement. The effects of topographical changes of implant surfaces induced by oxalic acid on BAF, mature bone, collagen contents, and type I collagen were significantly promoted with decreased immature bone formation and type III collagen in the later 4 weeks post-implantation.ConclusionsTreatment of implant surfaces with oxalic acid rapidly increases osseointegration from the early stages after implantation. Moreover, submicron topographical changes of dental implants induced by oxalic acid improve bone quality based on bone maturation and increased production of type I collagen surrounding dental implants in the late stage after implant placement.

Bone quality varies from one patient to another extensively. Young's modulus may deviate up to 40% of normal bone quality, which results into alteration of bone stiffness immensely. The prime goal of this study is to design the optimum dental implant considering the mechanical response at bone implant interfaces for a patient with specific bone quality. 3D models of mandible and natural molar tooth were prepared from CT scan data, while dental implants were modelled using different diameter, length and porosity and FE analysis was carried out. Based on the variation in bone density, five different bone qualities were considered. First, failure analysis of implants, under maximum biting force of 250 N had been performed. Next, the implants that remained were selected for observation of mechanical response at bone implant interfaces under common chewing load of 120 N. Maximum Von Mises stress did not surpass the yield strength of the implant material (TiAl4V). However, factor of safety of 1.5 was considered and all but two dental implants survived the design stress or allowable stress. Under 120 N load, distribution of Von Mises stress and strain at the boneimplant interface corresponding to the rest of the implants for five bone conditions were obtained and enlisted. Implants exhibiting interface strain within 1500-3000 microstrain range show the best bone remodelling and osseointegration. So, implant models having this range of interface strains were selected corresponding to the particular bone quality. A set of optimum dental implants for each of the bone qualities were predicted.

Chapter 11 - Bioactive Surface Coatings for Enhancing Osseointegration of Dental Implants

Tracheostomy care is a critical aspect of respiratory therapy, requiring specialized knowledge and adherence to standardized protocols to ensure optimal patient outcomes. However, variations in practice and a lack of formalized guidelines may contribute to inconsistencies in tracheostomy management. Therefore, this study aimed to assess clinical practices, self-confidence, and perceived barriers in tracheostomy care among respiratory therapists (RTs) in Saudi Arabia. A cross-sectional descriptive survey was distributed from June to October 2024 among RTs in Saudi Arabia. Descriptive and inferential statistical analyses were performed to identify key trends and associations. A total of 1,012 RTs participated in the study, with the majority being male (588, 58.1%). Tracheostomy care was available in 90.7% of hospitals, although 22.4% reported the absence of specific protocols. Formal training in tracheostomy care was limited, with only 42.3% of RTs receiving 1-5h of instruction. Attitude of evidence-based practices was generally positive, as 59.9% of respondents felt up to date with current guidelines. Confidence levels in managing tracheostomy patients were notably low (20.9%) and slightly higher for ventilator-assisted patients (23.6%). To enhance skills, 53.6% of RTs visited specialist centers, and many participated in conferences (52.2%) and workshops (49.2%). The most significant barriers to incorporating tracheostomy care into RT services included lack of knowledge (70.7%), inadequate training (59.7%), and the absence of standardized protocols (59.6%). Although RTs demonstrated a solid understanding of tracheostomy care, variations in clinical practices and confidence levels were observed, primarily due to the absence of standardized protocols and formal training. Implementing targeted educational initiatives and developing clear protocols could significantly improve the quality of tracheostomy care and enhance patient outcomes.

Bone mechanical function is regulated by bone quality and bone mineral density (BMD) that reflect bone strength. The preferential alignment of biological apatite (BAp) c-axis/collagen fibers and osteocytes is a determinant factor of bone quality. However, the effect of mechanical loading on bone quality around dental implants is unclear. The aim of this study was to clarify the effects of mechanical loading on osseointegration, bone volume BMD, and bone quality around dental implants. Twenty anodized Ti-6Al-4V alloy implants (KYOCERA Co., Kyoto, Japan) were placed in the proximal tibial metaphysis of 10 rabbits. Twelve weeks after surgery, mechanical loading was applied along the long axis of the implant (50 N, 3 Hz, 1,800 cycles, 2 days/week) for 8 weeks. Osseointegration, bone volume, BMD, and bone quality were evaluated using light microscopy, microcomputed tomography, polarized light microscopy, and microbeam X-ray diffractometer. Mechanical loading increased osseointegration, bone volume, and BMD. Bone quality around dental implant was altered with increased osteocyte numbers and the preferential alignment direction and degree of BAp c-axis/collagen fibers. These findings suggest that mechanical loading effectively induces bone anabolic responses around dental implants. Altered bone quality may upregulate bone strength, contributing to long-term implant stability.

The objective was to assess current emergency department (ED) provider practices and preferences for tobacco cessation interventions. The ED is an opportune place to initiate smoking cessation interventions. However, little is known about ED provider current practices and preferences for cessation counseling in the ED. This was a survey of ED providers conducted in 2008-2009 (including physicians, nurse practitioners, physician assistants, and nurses), working at least half-time at 10 U.S. academic EDs, regarding adherence to clinical practice guidelines ("5 As") and preferences for cessation interventions/styles. Data analysis occurred in 2012-2013. The response rate was 64% (800 out of 1,246 completed surveys). Providers reported strongest adherence to asking about patient smoking status, followed by advising, with significant variance by clinical role. Assessing, assisting, and arranging support for patients was low overall. Most frequently used interventions were to provide patients with a list of telephone numbers for stop-smoking counseling (87%), pamphlets on smoking health risks and the benefits of stopping (85%), and referrals to the National Toll-Free Smoker's Quitline (84%). Most providers (80%) were supportive of personally conducting brief (less than 3minutes) smoking cessation counseling sessions during the ED visit, emphasizing education and encouragement. The least appealing intervention was writing a prescription for nicotine replacement therapies or medications to stop smoking (35%). Interventions most likely to be used were brief and delivered with a positive tone and included referral to external resources. The logical next step is to design and test interventions that ED providers find acceptable.

Perceived knowledge among patients cared for by nephrologists about chronic kidney disease and end-stage renal disease therapies

Annotation. Dental implantation is a modern and effective method of treatment of complete or partial adentia, both on the upper and lower jaws. The process of dental implantation involves the installation of artificial structures in the place of lost teeth, in the jawbone, to which dental crowns or prostheses are then fixed. Dental implants allow you to get a permanent structure to restore lost teeth. Dental implantology has become one of the most widespread and popular fields in dentistry due to its effectiveness and durability. Every year, the number of patients who choose dental implants as a way to restore lost teeth is increasing, which is due to the awareness of their advantages compared to other methods. The development of new technologies and materials, such as biocompatible titanium alloys and digital planning, has made dental implantation more affordable and reliable, contributing to its growing popularity. Many dental clinics and medical institutions offer specialized courses and training in implantology for dentists, which increases the number of qualified specialists in this field. Implants provide a high quality of life, restoring the chewing function and the aesthetic appearance of the teeth, which contributes to their popularity among patients who are looking for a durable and comfortable solution. The increase in the number of clinics specializing in implantology, as well as the decrease in the cost of procedures thanks to competition and technological advances, make implants more accessible to a wide range of patients. The large number of patients who have had a positive experience with dental implants helps to spread information about this technique and increase its popularity through recommendations and reviews. Thus, dental implantology continues to develop and gain popularity in the dental market due to its many advantages, technological innovations and growing demand from patients.

Today, an entire range of highly effective osteoporosis medications is available. While the therapeutic potential of a drug for this indication was traditionally evaluated based on the increase in bone mineral density during treatment, in recent years this criterion has been replaced by the documented reduction in fractures. Current focus is therefore increasingly placed on achieving improvement in bone quality. Several medications, including the selective estrogen receptor modulator raloxifene, appear to be particularly noteworthy in this regard. New diagnostic methods such as high-resolution computed tomography facilitate not only bone density measurement, but also the qualitative and quantitative 3D representation of bone microarchitecture in vivo for the first time. Using this more modern technique, improvement in ‘bone quality’ has been documented in clinical practice in a retrospective as well as prospective analysis of postmenopausal osteoporotic patients receiving treatment with raloxifene.