Systemic antibiotics in the surgical treatment of peri-implantitis: A randomized placebo-controlled trial

AIM

To study the clinical, radiographic and microbiological outcomes after surgical treatment of peri-implantitis, with or without adjunctive systemic antibiotics.

MATERIALS AND METHODS

Eighty-four patients (113 implants) with peri-implantitis were randomized into three groups (A, amoxicillin and metronidazole; B, phenoxymethylpenicillin and metronidazole; or C, placebo). Treatment included resective surgery and implant surface decontamination with adjunctive antibiotics or placebo. Primary outcomes were probing pocket depth (PPD) reduction and marginal bone level (MBL) stability. Secondary outcomes were treatment success (defined as PPD ≤ 5 mm, bleeding on probing [BOP] ≤ 1site, absence of suppuration on probing [SOP] and absence of progressive bone loss of >0.5 mm), changes in BOP/SOP, mucosal recession (REC), clinical attachment level (CAL), bacterial levels and adverse events. Outcomes were evaluated for up to 12 months. The impact of potential prognostic indicators on treatment success was evaluated using multilevel logistic regression analysis.

RESULTS

A total of 76 patients (104 implants) completed the study. All groups showed clinical and radiological improvements over time. Statistically significant differences were observed between groups for MBL stability (A = 97%, B = 89%, C = 76%), treatment success (A = 68%, B = 66%, C = 28%) and bacterial levels of Aggregatibacter actinomycetemcomitans and Tannerella forsythia, favouring antibiotics compared to placebo. Multiple regression identified antibiotic use as potential prognostic indicator for treatment success. Gastrointestinal disorders were the most reported adverse events in the antibiotic groups.

CONCLUSIONS

Adjunctive systemic antibiotics resulted in additional improvements in MBL stability. However, the potential clinical benefits of antibiotics need to be carefully balanced against the risk of adverse events and possible antibiotic resistance.

Antibiotic prescription in bone augmentation and dental implant procedures: a multi-center study

BACKGROUND

Adherence to antibiotic recommendations and safety aspects of restrictive use are important components when combating antibiotic resistance. The primary aim of this study was to assess the impact of national guidelines on antibiotic prescriptions for bone augmentation procedures among dentists working at three specialized clinics. The secondary aim was to assess the occurrence of postoperative infections.

METHODS

Medical charts of 400 patients treated with bone augmentation were reviewed: 200 in the years 2010-2011 and 200 in 2014-2015. The Swedish national recommendations for antibiotic prophylaxis were published in 2012.

RESULTS

There was a wide variation in antibiotic regiments prescribed throughout the study. The number of patients treated with antibiotic prophylaxis in a single dose of 2 g amoxicillin, and treated as advocated in the national recommendations, was low and decreasing between the two time periods from 25% (n = 50/200) in 2010-2011 to 18.5% (n = 37/200) in 2014-2015. The number of patients not given any antibiotics either as a prophylactic single dose or during the postoperative phase increased (P < 0.001). The administration of a 3-7-days antibiotic prescription increased significantly from 25.5% in 2010-2011 to 35% in 2014-2015. The postoperative infection rates (4.5% and 6.5%) were without difference between the studied periods. Smoking and omitted antibiotic prophylaxis significantly increased the risk of postoperative infection. Logistic regression analyses showed that patient male gender and suffering from a disease were predictive factors for the clinician to adhere to the guidelines.

CONCLUSIONS

After introduction of national recommendations for antibiotic prophylaxis before bone augmentation procedures, the patient group receiving a single preoperative dose decreased while the group not given antibiotic prophylaxis increased. There was no difference in occurrence of postoperative infections between the two time periods. The results indicate a need for educational efforts and strategies for implementation of antibiotic prudence and awareness among surgeons performing bone augmentation procedures.

Oral streptococcal infective endocarditis among individuals at high risk following dental treatment: a nested case-crossover and case-control study

Background

It is not clear whether Viridans Group Streptococcal Infective Endocarditis (VGS-IE) among individuals at high risk is more frequent following bacteraemia caused by invasive dental procedures (IDPs) than after daily bacteraemia caused by chewing and tooth brushing. The aim of this nested study was to assess if VGS-IE was temporally associated with IDPs in a national cohort of individuals at high risk.

Methods

This nested case-control and case-crossover study was based on a Swedish national cohort study of 76,762 individuals at high risk of IE due to complex congenital heart disease, prosthetic heart valve or previous IE. Participants were living in Sweden between July 1st, 2008 and January 1st, 2018. The frequency of IDPs during the 3 months before VGS-IE was calculated and compared to controls (sampled 1:10). A case-crossover study was conducted to account for residual confounders. Participants were identified using the national patient register, and IDPs were identified using the national dental health register.

Findings

98,247 IDPs were carried out in the cohort during the study period: 624 occasions of oral surgery, 44,190 extractions and 53,433 sessions of subgingival scaling. The study could not confirm that IDPs were more common among cases (4.6%) than controls (4.1%), OR = 1.22 [95% Confidence Interval (CI) 0.64-2.3], or during case- (3.3%) than reference periods (3.8%), OR = 0.89 [95% CI: 0.68-1.17]. Restricting the analysis to the period when cessation of antibiotic prophylaxis for the prevention of IE in Swedish dentistry was recommended, from the 1st of October 2012 to the 1st of January 2018, did not alter the results of the case-control study: OR 0.64, 95% CI: 0.20-2.09, or the case-crossover study: OR 0.58, 95% CI: 0.15-2.19.

Interpretation

The study could not confirm that VGS-IE is associated with IDPs among individuals at high risk. A study with larger sample size could clarify whether there is a lack of association. The finding of a small (<5%) proportion of cases temporally associated with IDPs is similar to that of the previous large-scale study on IDPs and VGS-IE.

Funding

Funding was provided by the Board of doctoral education at Karolinska Institutet, the Public Health Agency of Sweden, Folktandvården Stockholm AB, Steering Group for Collaborative Odontological Research at Karolinska Institutet and Stockholm City County, and the Swedish Dental Association.

Dental implant procedures contribution to the total antibiotic use in Swedish dentistry. A register-based study

OBJECTIVE

To study the influence of demographic and organizational factors to antibiotic utilization in dental implant surgery in Sweden.

MATERIAL AND METHODS

Descriptive statistics regarding antibiotic prescription between 2009 and 2019 was retrieved from two national registers, the Swedish Prescribed Drug Register and the Dental Health register, both administered by the National Board of Health and Welfare.

RESULTS

During the years 2009-2019 a significant decrease of the proportion of prescriptions of systemic antibiotics in conjunction with implant surgical procedures occurred in all patient groups where the most common procedure was the insertion of a single implant. The proportion of dental visits when implant surgical treatment was performed which resulted in a prescription of antibiotics decreased significantly from 1/3 to approximately 1/5. However, comparing Public and Private dental care providers, the reduction was significantly greater in Public dental care. Patients with low level of education in urban regions, treated in Private dental clinics were more likely to receive antibiotics in conjunction to implant surgery compared to other groups. Phenoxymethylpenicillin is the most widely used substance in conjunction with implant surgery.

CONCLUSION

There is still room for improvement in reduction of antibiotic prescriptions in conjunction to implant surgical procedures in Sweden.

Infective Endocarditis Among High-risk Individuals Before and After the Cessation of Antibiotic Prophylaxis in Dentistry: A National Cohort Study

BACKGROUND

A few years after the publication of the British guidelines, national recommendations were published by the Swedish Medical Products Agency in October 2012, promoting the cessation of antibiotic prophylaxis in dentistry for the prevention of infective endocarditis (IE). The aim of this study was to evaluate whether the incidence of oral streptococcal IE increased among high-risk individuals after October 2012.

METHODS

This nationwide cohort study included all adult individuals (>17 years) living in Sweden from January 2008 to January 2018, with a diagnose code or surgical procedure code indicating high risk of IE. Cox proportional hazard models were performed to calculate adjusted ratios of oral streptococcal IE before and after October 2012 between high-risk individuals and references.

RESULTS

This study found no increased incidence of oral streptococcal IE among high-risk individuals during the 5 years after the cessation, compared with before. Hazard rate ratios were 15.4 (95% confidence interval [CI]: 8.3-28.5) before and 20.7 (95% CI: 10.0-42.7) after October 2012 for prevalent high-risk individuals. Corresponding ratios for incident high-risk individuals were 66.8 (95% CI: 28.7-155.6) and 44.6 (95% CI: 22.9-86.9). Point estimates for interaction with time period were 1.4 (95% CI: .6-3.5) and 0.8 (95% CI: .5-1.3) for prevalent and incident high-risk individuals, respectively.

CONCLUSION

The results suggest that the current Swedish recommendation not to administer antibiotic prophylaxis for the prevention of IE in dentistry has not led to an increased incidence of oral streptococcal IE among high-risk individuals.

Antibiotic utilization in emergency dental care in Stockholm 2016: a cross sectional study

OBJECTIVES

To investigate systemic antibiotics utilization in emergency dental care and to determine the most common treatment measures performed during emergency visits in public versus private emergency care in Sweden.

MATERIAL AND METHODS

Two questionnaires were answered by dentists at one large public and one large private emergency dental clinic in Stockholm, Sweden. The first questionnaire pertained to the emergency care provided to patients (n = 1023) and the second concerned the dentists' (n = 13) own knowledge and attitudes towards antibiotic treatment and oral infections. The results of the questionnaires were tested using a Chi-square test.

RESULTS

Sixteen percent of all patients seeking emergency dental treatment received antibiotics. The most common overall reason for visiting an emergency clinic was pain (52%, n = 519). The most common diagnoses made by the participating dentists in the public clinic were tooth/filling fracture (17%, n = 91) and gingivitis (14%, n = 76), while in the private clinic they were tooth fracture (29%, n = 146) and symptomatic apical periodontitis (15%, n = 72). Although the number of patients with infection was higher in the public care clinic, there was no significant difference in total number of antibiotic prescriptions between the two clinics. The rate of patients receiving antibiotic prescription as sole treatment was 41% (n = 34) in private care and 31% (n = 18) in public care. Thirty-one percent (n = 4) of dentists prescribed antibiotics for patients with diagnoses normally not requiring antibiotics, citing reasons such as time limitation, patient request, patient travel, patient safety, and follow-up not possible.

CONCLUSION

Although antibiotic prescription frequency among the Swedish emergency care dentists participating in this study was low, areas for improvement could include providing education to improve dentists' knowledge on both antibiotic prescription in emergency dental care and treatment of acute oral infections.

Healthcare Challenges and Future Solutions in Dental Practice: Assessing Oral Antibiotic Resistances by Contemporary Point-Of-Care Approaches

Antibiotic resistance poses a global threat, which is being acknowledged at several levels, including research, clinical implementation, regulation, as well as by the World Health Organization. In the field of oral health, however, the issue of antibiotic resistances, as well as of accurate diagnosis, is underrepresented. Oral diseases in general were ranked third in terms of expenditures among the EU-28 member states in 2015. Yet, the diagnosis and patient management of oral infections, in particular, still depend primarily on empiric means. On the contrary, on the global scale, the field of medical infections has more readily adopted the integration of molecular-based systems in the diagnostic, patient management, and antibiotic stewardship workflows. In this perspective review, we emphasize the clinical significance of supporting in the future antibiotic resistance screening in dental practice with novel integrated and point-of-care operating tools that can greatly support the rapid, accurate, and efficient administration of oral antibiotics.

Effect of governmental strategies on antibiotic prescription in dentistry

Objective: To study the effect of governmental strategies, to constitute and publish recommendations on antibiotic usage in dentistry, on the antibiotic consumption.Material and methods: Descriptive statistics regarding antibiotic prescription between 2009 and 2017 was retrieved from two national registers, the Swedish Prescribed Drug Register and the Dental Health register, both administered by the National Board of Health and Welfare. Age standardization was applied to alleviate the comparison between gender, different regions and years.Results: The number of dispatched prescriptions of antibiotics from dentists was reduced with 31% during the study period. 10% of the visits to a dentist generated an antibiotic prescription corresponding to 7% of the total number of antibiotic prescriptions. A decline in prescription was observed after publication of national recommendations for antibiotics prophylaxis in 2012 and antibiotic treatment in 2014. Unexplained geographical and gender differences in the rates of prescription were seen.Conclusions: Data indicates a correlation between introduction of governmental strategies to reduce antibiotic usage and declining antibiotic prescription. Although a marked reduction in prescription was observed, the results indicate that there is further potential for improvement of antibiotic stewardship in odontology.

Incidence of infective endocarditis caused by viridans group streptococci in Sweden - effect of cessation of antibiotic prophylaxis in dentistry for risk individuals

Introduction

In October 2012, the Swedish Medical Products Agency published new recommendations for the cessation of prophylactic antibiotics in dentistry for the prevention of infective endocarditis (IE). Previously, 2 g of amoxicillin per os would be administered 1 h before invasive dental procedures to patients with valve prosthesis, complicated heart valve disease, and to those with previous endocarditis.

Objectives

The aim of this study was to evaluate whether the total incidence of IE caused by oral viridans group streptococci (VGS) or IE caused by staphylococci, increased in Sweden after the introduction of the new recommendations.

Methods

The incidence of IE in Sweden before and after October 2012 was calculated and compared using an interrupted time series analysis. Separate analyses were conducted for the total incidence of IE, and IE caused by VGS or Staphylococcus aureus. Cases of IE were identified using the Swedish national registry of IE, which has existed since 1995 and contains data from all Swedish hospital clinics specialising in infectious disease. All cases with hospital admission date from the 1^st of Jan 2008, to the 31^st of Dec 2017 were included. The incidence calculations were corrected for annual changes in population size using data from the Swedish government agency Statistics Sweden.

Results

The results show no statistically significant increase in the slope of the trend line of the total incidence of IE, IE caused by VGS or S. aureus in the Swedish general population after October 2012, compared to before.

Conclusion

The results suggest that the recommended cessation of prophylactic antibiotics for the prevention of IE in dentistry has not led to an increased incidence of IE caused by oral streptococci among the Swedish population.

Stakeholder Perception of the Professional Role and Competence of Swedish Dental Hygienists: A Questionnaire and Interview Study

Objectives:

This study investigated stakeholder opinions on the competence and role of dental hygienists in Sweden.

Materials and Methods:

A questionnaire was sent by e–mail to 94 stakeholders in eight Swedish counties. The survey queried the competence of recently graduated dental hygienists in skills in collaboration, communication, and problem–solving, and in clinical skills. In addition, 10 stakeholders from different Swedish dental organizations agreed to one–on–one deep interviews. Open–ended questions focused on dental hygienist competence to perform dental hygienist skills and tasks and to collaborate with other dental professionals and health–care professionals. Further topics concerning the dental hygienist included their future role and working in other European countries. The interviews were transcribed and then coded using qualitative conventional content analysis methods.

Results:

The stakeholder consensus in both the questionnaires and the interviews was that the dental hygienist profession is essential to modern dental care. The professional knowledge possessed by dental hygienists is unique and their role has developed and broadened over the years. Furthermore, the qualitative content analysis of the deep interviews identified a core category: The dental hygienist is an important profession for good oral health.

Conclusion:

Dental hygienists, responsible for prevention and oral health promotion, are an important members of the modern dental team. The need for dental hygienists to collaborate with other dental and general health–care professionals to meet the future demands of society will increase.

Prophylactic antibiotics for staged bone augmentation in implant dentistry

Background: The objective of the study was to assess the effect of prophylactic antibiotics on the outcome of bone augmentation and subsequent dental implant placement by combining the recommended quality assessment methods for systematic reviews and primary studies.Materials and methods: This is a complex systematic review in which systematic reviews as well as primary studies are scrutinised. A search of Medline (OVID), The Cochrane Library (Wiley) and EMBASE, PubMed and Health technology assessment (HTA) organisations as-well as a complementary hand-search was carried out. Selected primary studies were assessed using GRADE. Each study was reviewed by three authors independently.Results: Abstract screening yielded six potential systematic reviews allocated for full-text inspection. A total of ten primary studies were read in full-text. No relevant systematic reviews regarding the topic of this article were found. The quality assessment resulted in two primary studies with a moderate risk of bias. Of the two studies with a moderate risk of bias, one compared a single dose of clindamycin 600 mg preoperatively with the same preoperative dose followed by four doses of 300 mg every 6 h. The second study compared a single dose prophylaxis of two different types of antibiotic compounds.Conclusion: In conclusion, the scientific evidence regarding the use of antibiotic prophylaxis for reducing the risk of infection in conjunction with bone augmentation procedures during dental implant placement is very limited. The infection rate as compared to nonusage of prophylactic antibiotics, selection of the most suitable compound, and the optimal duration of prophylactic treatment is still unknown.

Heparin-binding protein in ventilator-induced lung injury

Background

Although mechanical ventilation is often lifesaving, it can also cause injury to the lungs. The lung injury is caused by not only high pressure and mechanical forces but also by inflammatory processes that are not fully understood. Heparin-binding protein (HBP), released by activated granulocytes, has been indicated as a possible mediator of increased vascular permeability in the lung injury associated with trauma and sepsis. We investigated if HBP levels were increased in the bronchoalveolar lavage fluid (BALF) or plasma in a pig model of ventilator-induced lung injury (VILI). We also investigated if HBP was present in BALF from healthy volunteers and in intubated patients in the intensive care unit (ICU).

Methods

Anaesthetized pigs were randomized to receive ventilation with either tidal volumes of 8 ml/kg (controls, n = 6) or 20 ml/kg (VILI group, n = 6). Plasma and BALF samples were taken at 0, 1, 2, 4, and 6 h. In humans, HBP levels in BALF were sampled from 16 healthy volunteers and from 10 intubated patients being cared for in the ICU.

Results

Plasma levels of HBP did not differ between pigs in the control and VILI groups. The median HBP levels in BALF were higher in the VILI group after 6 h of ventilation compared to those in the controls (1144 ng/ml (IQR 359–1636 ng/ml) versus 89 ng/ml (IQR 33–191 ng/ml) ng/ml, respectively, p = 0.02).

The median HBP level in BALF from healthy volunteers was 0.90 ng/ml (IQR 0.79–1.01 ng/ml) as compared to 1959 ng/ml (IQR 612–3306 ng/ml) from intubated ICU patients (p < 0.001).

Conclusions

In a model of VILI in pigs, levels of HBP in BALF increased over time compared to controls, while plasma levels did not differ between the two groups.

HBP in BALF was high in intubated ICU patients in spite of the seemingly non-harmful ventilation, suggesting that inflammation from other causes might increase HBP levels.

Electronic supplementary material

The online version of this article (10.1186/s40635-018-0198-x) contains supplementary material, which is available to authorized users.

Antibiotic prophylaxis in orthognathic surgery: A complex systematic review

Objective

In orthognathic surgery, antibiotics are prescribed to reduce the risk of postoperative infection. However, there is lack of consensus over the appropriate drug, the dose and duration of administration. The aim of this complex systematic review was to assess the effect of antibiotics on postoperative infections in orthognathic surgery.

Methods

Both systematic reviews and primary studies were assessed. Medline (OVID), The Cochrane Library (Wiley) and EMBASE (embase.com), PubMed (non-indexed articles) and Health Technology Assessment (HTA) publications were searched. The primary studies were assessed using GRADE and the systematic reviews by AMSTAR.

Results

Screening of abstracts yielded 6 systematic reviews and 36 primary studies warranting full text scrutiny. In total,14 primary studies were assessed for risk of bias. Assessment of the included systematic reviews identified two studies with a moderate risk of bias, due to inclusion in the meta-analyses of primary studies with a high risk of bias. Quality assessment of the primary studies disclosed one with a moderate risk of bias and one with a low risk. The former compared a single dose of antibiotic with 24 hour prophylaxis using the same antibiotic; the latter compared oral and intravenous administration of antibiotics. Given the limited number of acceptable studies, no statistical analysis was undertaken, as it was unlikely to contribute any relevant information.

Conclusion

With respect to antibiotic prophylaxis in orthognathic surgery, most of the studies to date have been poorly conducted and reported. Thus scientific uncertainty remains as to the preferred antibiotic and the optimal duration of administration.

Heparin-binding protein as a biomarker of acute kidney injury in critical illness

BACKGROUND

There is no biomarker with high sensitivity and specificity for the development of acute kidney injury (AKI) in a mixed intensive care unit (ICU) population. Heparin-binding protein (HBP) is released from granulocytes and causes increased vascular permeability which plays a role in the development of AKI in sepsis and ischemia. The aim of this study was to investigate whether plasma levels of HBP on admission can predict the development of AKI in a mixed ICU population and in the subgroup with sepsis.

METHODS

Longitudinal observational study with plasma HBP levels from 245 patients taken on admission to ICU. Presence and severity of AKI was scored daily for 1 week.

RESULTS

Mean (95% CI) plasma concentrations of log HBP (ng/ml) in the groups developing different stages of AKI were: stage 0 (n = 175), 3.5 (3.4-3.7); stage 1 (n = 33), 3.7 (3.5-4.0), stage 2 (n = 20), 4.4 (3.5-4.8); and stage 3 (n = 17), 4.6 (3.8-5.2). HBP levels were significantly higher in patients developing AKI stage 3 (P < 0.01) compared to AKI stage 0 and 1. The area under the curve (AUC) for HBP to discriminate the group developing AKI stage 2-3 was 0.70 (CI: 0.58-0.82) and in the subgroup with severe sepsis 0.88 (CI: 0.77-0.99).

CONCLUSION

Heparin-binding protein levels on admission to ICU are associated with the development of severe kidney injury. The relationship between HBP and AKI needs to be further validated in larger studies.

Post-operative nausea and vomiting in bariatric surgery patients: an observational study

BACKGROUND

The risk of post-operative nausea and vomiting (PONV) in patients undergoing bariatric surgery is unclear. The aim of the study was to investigate the risk of PONV and the use and effectiveness of PONV prophylaxis.

METHODS

This prospective observational study included 74 patients undergoing bariatric surgery with total intravenous anaesthesia. Patients were given PONV prophylaxis based on published guidelines and a simplified PONV risk score. Perioperative data were collected and a questionnaire was used at 2, 4, 6, 24, 48 and 72 h after the operation to evaluate PONV. Data are presented as risk (%) with the 95% confidence interval.

RESULTS

Sixty five per cent (54-75) of the patients experienced PONV in the first 24 post-operative hours and the risk increased with the number of risk factors for PONV. PONV occurred in 78% (66-87) of women and 26% (12-49) of men during the first 24 h. In relation to the guidelines, one patient received suboptimal PONV prophylaxis, 23% received optimal prophylaxis and 76% supra-optimal prophylaxis. The risk of PONV was 82% (59-94) with optimal prophylaxis and 59% (46-71) with supra-optimal prophylaxis. Of all patients, 34% (24-45) experienced severe PONV in the first 24 h that limited their activity.

CONCLUSIONS

The incidence of PONV in bariatric surgery patients was high despite a PONV prophylaxis regime following current guidelines. These results cast doubt as to the effectiveness of the usual PONV prophylaxis in this patient group and point to the need for further investigation of PONV prophylaxis and treatment in bariatric surgery patients.

The patient undergoing implant therapy. Summary and consensus statements. The 4th EAO Consensus Conference 2015

INTRODUCTION

The assignment for this working group was to update the existing knowledge regarding factors considered being of special relevance for the patient undergoing implant therapy. This included areas where conflicting opinions exists since long or recently has been expressed, like the role of antibiotic prophylaxis in dental implant surgery and peri-implantitis. Also areas with growing interest and concern such as patient-reported outcome measures (PROMs) and health-economy was included in this review.

MATERIALS AND METHODS

The literature in the respective areas of interest (antibiotic prophylaxis, peri-implantitis, patient-reported outcome measurements and health-economic aspects) was searched using different strategies for the different papers. Search strategies ranged from a complex systematic review to systematic- and narrative reviews, depending on subject and available literature. All collected material was critically reviewed. Four manuscripts were subsequently presented for group analysis and discussion and plenum discussions and concensus approval. The selected areas were considered to be of key importance and relevance for the patient undergoing implant therapy.

RESULTS

The results and conclusions of the review process are presented in the respective papers. The group's conclusions, identified knowledge gaps, directions for future research and concensus statements are presented in this article. The following reviews were available for group discussions and the foundation for subsequent plenary sessions: Lund B, Hultin M, Tranaeus S, Naimi-Akbar A, Klinge B. (2015) Perioperative antibiotics in conjunction with dental implant placement. A complex systematic review. Renvert S & Quirynen M. (2015) Risk indicators for peri-implantitis. A narrative review. De Bruyn H, Raes S, Matthys C, Cosyn J. (2015) The current use of patient centered/reported outcomes in implant dentistry. A systematic review. Beikler T & Flemmig T.F. (2015) Economic evaluation of implant-supported prostheses. A narrative review.

Long-term subarachnoid haemorrhage survivors still die due to cerebrovascular causes

OBJECTIVE

Subarachnoid haemorrhage (SAH) is associated with sympathetic nervous activation and inflammation. SAH could therefore theoretically be a risk factor for development of cardiovascular disease. The aim of this study was to investigate whether long-term (≥1 year) SAH survivors had an increased risk of death due to cardiovascular causes.

MATERIAL & METHODS

SAH patients ≥18 years treated at Umeå University Hospital between 1986 and 2006 were eligible for inclusion. Deceased patients were identified in the Swedish population register. Death certificates from long-term SAH survivors and causes of death in the general population were obtained from the National Board of Health and Welfare, Sweden. The prevalence of comorbidities at the time of SAH was compared with the distribution of cardiovascular risk factors in the northern Sweden MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Disease) health survey. Analyses were stratified for age and sex.

RESULTS

In the SAH patients, the median year of SAH was 1992 and the median year of death was 2001. The MONICA survey in 1994 and the distribution of deaths in the general population in 2001 were used for comparison. Long-term SAH survivors had, compared to the general population, a significantly increased risk for death due to cerebrovascular disease (P < 0.0001), but not for death due to cardiovascular disease. Hypertension was more common in SAH patients compared to survey participants (P < 0.01).

CONCLUSION

Cerebrovascular causes of death were significantly more common in long-term survivors after SAH compared to the general population.

Medical screening in dental settings: a qualitative study of the views of authorities and organizations

Background

The practice of identifying individuals with undiagnosed diabetes mellitus type II or undiagnosed hypertension by medical screening in dental settings has been received positively by both patients and dentistry professionals. This identification has also shown to be cost-effective by achieving savings and health benefits, but no investigation has been made of the attitudes of authorities and organizations. The aim of this study was to describe the views of authorities and organizations.

Results

Thirteen authorities and organizations were interviewed of the sample of 20 requested. Seven approached authorities and organizations did not believe it was relevant to participate in the study. The manifest analysis resulted in four categories: medical screening ought to be established in the society; dentistry must have relevant competence to perform medical screening; medical screening requires cooperation between dentistry and health care; and dentistry is not the only context where medical screening could be performed. The latent analysis resulted in an emerging theme: positive to, but uncertain about, the concept of medical screening in dental settings. The spokespersons for the approached authorities and organizations had a positive view of medical screening but the respondents experienced a lack of facts concerning the scientific communities’ position, guidelines and procedures in the topic.

Conclusions and implications

Approached authorities and organizations generally had a positive view of medical screening in dental settings but were uncertain about the concept. Further scientific knowledge and guidelines concerning the topic are needed before it can be commonly introduced and additional research on implementation strategies and long-term follow-up of medical screening are needed.

Reimbursement systems influence prosthodontic treatment of adult patients

OBJECTIVE

To evaluate the influence of reimbursement system and organizational structure on oral rehabilitation of adult patients with tooth loss.

MATERIALS AND METHODS

Patient data were retrieved from the databases of the Swedish Social Insurance Agency. The data consisted of treatment records of patients aged 19 years and above claiming reimbursement for dental care from July 1, 2007 until June 30, 2009. Before July 1, 2008, a proportionately higher level of subsidy was available for dental care in patients 65 years and above, but thereafter the system was changed, so that the subsidy was the same, regardless of the patient's age. Prosthodontic treatment in patients 65 years and above was compared with that in younger patients before and after the change of the reimbursement system. Prosthodontic treatment carried out in the Public Dental Health Service and the private sector was also analyzed.

RESULTS

Data were retrieved for 722,842 adult patients, covering a total of 1,339,915 reimbursed treatment items. After the change of the reimbursement system, there was a decrease in the proportion of items in patients 65 years and above in relation to those under 65. Overall, there was a minimal change in the proportion of treatment items provided by the private sector compared to the public sector following the change of the reimbursement system.

CONCLUSIONS

Irrespective of service provider, private or public, financial incentive such as the reimbursement system may influence the provision of prosthodontic treatment, in terms of volume of treatment.

Complex systematic review - Perioperative antibiotics in conjunction with dental implant placement

OBJECTIVES

The aim of this study was to revisit the available scientific literature regarding perioperative antibiotics in conjunction with implant placement by combining the recommended methods for systematic reviews and complex systematic reviews.

MATERIAL AND METHODS

A search of Medline (OVID), The Cochrane Library (Wiley), EMBASE, PubMed and Health technology assessment (HTA) organizations was performed, in addition to a complementary hand-search. Selected systematic reviews and primary studies were assessed using GRADE and AMSTAR, respectively. A meta-analysis was performed.

RESULTS

The literature search identified 846 papers of which 10 primary studies and seven systematic reviews were included. Quality assessment of the systematic reviews revealed two studies of moderate risk of bias and five with high risk of bias. The two systematic reviews of moderate risk of bias stated divergent numbers needed to treat (NNT) to prevent one patient from implant failure. Four of the primary studies comparing antibiotic prophylaxis with placebo were estimated to be of low, or moderate, risk of bias and subjected to meta-analysis. The NNT was 50 (pooled RR 0.39, 95% CI 0.18, 0.84; P = 0.02). None of these four studies individually show a statistical significant benefit of antibiotic prophylaxis. Furthermore, narrative analysis of the studies eligible for meta-analysis reveals clinical heterogeneity regarding intervention and smoking.

CONCLUSION

Antibiotic prophylaxis in conjunction with implant placement reduced the risk for implant loss by 2%. However, the sub-analysis of the primary studies suggests that there is no benefit of antibiotic prophylaxis in uncomplicated implant surgery in healthy patient.

Antibiotic prescription patterns among Swedish dentists working with dental implant surgery: adherence to recommendations

OBJECTIVES

To investigate antibiotic prophylaxis prescription behaviors among Swedish dentists working with dental implant surgery and the influence of scientific reviews.

MATERIAL AND METHODS

An observational questionnaire study was conducted in 2008 and 2012. Dental clinic addresses were found through online search services of Swedish telephone directories. The questionnaires were posted to eligible dentists (120 in 2008, 161 in 2012) in the Stockholm region, Sweden. Absolute frequencies were used to describe the data. Chi-square tests were applied to assess statistically significant differences.

RESULTS

The response rate was 75% in 2008 and 88% in 2012. In 2008, 88% of the dentists routinely prescribed antibiotic prophylaxis when performing implant surgery and 74% in 2012 (P = 0.01). There was a significant reduction in the dentists prescription patterns as 65% prescribed a single dose in 2012, compared to 49% in 2008 (P = 0.04). Amoxicillin was the drug of choice for 47% of the respondents in 2012, and 21% in 2008 (P = 0.01). Dentists without postgraduate clinical training were significantly more prone to extend antibiotic administration after surgery (P < 0.009).

CONCLUSIONS

There is a wide variation in the choice of compound and prescription patterns of prophylactic antibiotic prior to implant insertion. A reduction in antibiotic prescription to a single dose was observed comparing 2008 and 2012, probably influenced by scientific reviews. Dentists with postgraduate education are more likely to limit antibiotic usage.

Developing implant dentistry education in Europe: the continuum from undergraduate to postgraduate education and continuing professional development

INTRODUCTION

Implant dentistry is a treatment modality which has mainstream clinical practice of comprehensive care, which however is not adequately represented in the undergraduate dental curricula. A consensus workshop organised by ADEE in 2008, set the benchmarks for the knowledge and competences a modern dental practitioner must possess with regard to implant dentistry, as well as defined undergraduate and postgraduate pathways for the acquisition of these competences. Today, 5 years later, there exist several challenges for the implementation of these benchmarks in both undergraduate curricula but also post-graduation educational pathways.

METHODS

A consensus workshop was organised by ADEE, bringing together 48 opinion leaders, including academic teachers of all disciplines related to implant dentistry, specialists, representatives of relevant scientific and professional associations, as well as industry delegates. The objectives of the workshop were to evaluate the existing scientific literature, reported experience and best practices in order to identify potential and limitations for the implementation of implant dentistry in the undergraduate curriculum, as well produce recommendations for the optimal educational structures for postgraduate programmes and continuing professional development.

RESULTS

The scientific committee conducted two European-wide questionnaire surveys to better document the current state of education in implant dentistry. Upon completion of the surveys, reviewers were appointed to produce three scientific review papers, identifying current achievements and future challenges. Finally, during the 3 days of the workshop, all the evidence was reviewed and the main conclusions and recommendations that were adopted by all participants are reported in the present Consensus Paper.

CONCLUSIONS

Implementation of implant dentistry in the undergraduate curriculum has improved significantly, but still lags behind the benchmarks set in 2008 and the diversity between institutions remains big. At the post-graduation level, there is currently a wide diversity of courses and pathways towards competences related to implant dentistry and there is at present a great need for quality assurance, as well as standardisation and transparency of the learning outcomes.

Clinical advantages of computer-guided implant placement: a systematic review

OBJECTIVES

To systematically scrutinize the current scientific literature regarding the clinical advantages of computer guidance of implant placement.

MATERIALS AND METHODS

Four electronic databases were searched using specified indexing terms. The reference lists of publications were also searched manually. For inclusion, publications had to meet pre-established criteria.

RESULTS

The searches yielded 1028 titles and abstracts. After data extraction and interpretation, 28 publications and 2 systematic reviews remained for inclusion. Fifteen studies were prospective observational and four were retrospective observational. Nine studies included a control group (controlled clinical trials) of which seven were prospective and two retrospective. Only three of the prospective studies were randomized (RCT's). A total of 852 patients were treated with 4032 implants using computer-guided implant surgery. The number of patients included in each study ranged from 6 to 206. The age ranged from 16 to 92 years and the follow-up period varied between 1 and 49 months.

CONCLUSIONS

The limited scientific evidence available suggests that guided placement has at least as good implant survival as conventional protocols. However, several unexpected procedure-linked adverse events during guided implant placement indicate that the clinical demands on the surgeon were no less than those during conventional placement. A clinical advantage with flapless guided surgery is that the technique is likely to decrease pain and discomfort in the immediate postoperative period.

Qualitative studies of patients' perceptions of loss of teeth, the edentulous state and prosthetic rehabilitation: a systematic review with meta-synthesis

OBJECTIVE

To conduct a systematic review and meta-synthesis of qualitative studies addressing patients' perceptions of loss of teeth, edentulism and oral rehabilitation.

BACKGROUND

Qualitative studies can complement quantitative studies by achieving deep understanding of patients' subjective experiences of losing teeth and coping with edentulism. They can also explore the perception that the benefits of prosthetic rehabilitation extend far beyond primary clinical treatment goals of restoration of oral function.

MATERIALS AND METHODS

The major data bases were searched extensively for relevant qualitative and quantitative studies, followed by manual searching of the reference lists of included publications. Two authors independently read all abstracts. Relevant papers were retrieved in full-text and included or excluded according to a specially designed protocol. The included articles were then appraised and rated for quality: high, moderate or low. Articles of low quality were excluded.

RESULTS

The database search yielded 36 abstracts of qualitative studies; manual search disclosed one further article. All were read in full-text by two independent authors: 28 were excluded. Of the remaining nine, two (assessed as of low quality) were excluded for further analysis. Meta-synthesis, based on seven studies, disclosed two major themes: loss of quality-of-life associated with losing teeth and restored quality-of-life after oral rehabilitation.

CONCLUSIONS

In this relatively new field of research, there are few published papers. Nevertheless, the studies to date show that loss of teeth is associated not only with compromised oral function, but also loss of social status and diminished self-esteem. Oral rehabilitation has broad positive implications, restoring quality of life and self-worth.

Treatment of adult patients with partial edentulism: a systematic review

PURPOSE

The purpose of this systematic review was to identify and critically appraise published studies of treatment methods used in general practice to rehabilitate adult patients with single tooth loss or partial edentulism, with special emphasis on outcomes reported after at least 5 years of follow-up.

MATERIALS AND METHODS

Three databases were searched using specified indexing terms. Publications were included if the study design, research questions, and sample size satisfied pre-established criteria. Reference lists of relevant publications and systematic reviews were also searched. The quality of evidence was classified according to the GRADE system as high, moderate, low, or very low.

RESULTS

The search yielded 7,675 titles, of which 1,130 were read in full text. A final total of 15 publications were deemed eligible for inclusion: 5 of moderate quality and 10 of low quality. The five studies of moderate quality were all related to implant-based treatment. The 5-year survival rates for implant-supported single crowns and prostheses were 91% and 94.7%, respectively (implant survival rates: 98.5% and 94.9%, respectively). The underlying scientific evidence was low in quality. No relevant publications were identified regarding the economic aspects of treatment.

CONCLUSION

Due to the low scientific evidence of the included studies, it was not possible to compare various treatment methods used for rehabilitation of single tooth loss or partial edentulism.

Oral rehabilitation of tooth loss: a systematic review of quantitative studies of OHRQoL

PURPOSE

This study aimed to review published quantitative studies for evidence regarding the influence of oral rehabilitation following total or partial tooth loss on self-perceived oral health-related quality of life (OHRQoL).

MATERIALS AND METHODS

Three databases were searched using specified indexing terms. The reference lists of relevant publications were also searched manually. Quality of evidence was classified according to GRADE guidelines as high, moderate, low, or very low.

RESULTS

The search yielded 2,138 titles and abstracts, 2,102 of which were of a quantitative study design. Based on pre-established criteria, the full-text versions of 322 articles were obtained. After data extraction and interpretation, 5 publications of high or moderate study quality remained. The results of these 5 studies showed positive effects of oral rehabilitation on OHRQoL. Two studies showed substantial improvements.

CONCLUSIONS

This is a relatively new field of research; there are very few quantitative studies of how patients perceive OHRQoL following tooth loss and subsequent rehabilitation. While this review indicates that treatment has positive effects on quality of life, the scientific basis is insufficient to support general conclusions about the influence of various interventions on the OHRQoL of patients who have experienced total or partial tooth loss. To achieve a more comprehensive analysis, it is recommended that future studies be based on a combination of quantitative and qualitative methods, ie, questionnaires and semi-structured interviews. The follow-up period must also be appropriate for the specific intervention studied.

Treatment of adult patients with edentulous arches: a systematic review

PURPOSE

This study aimed to evaluate the outcomes of treatment methods used to rehabilitate adult patients with maxillary and/or mandibular edentulism after at least 5 years of follow-up. The risks, adverse effects, and cost effectiveness of these methods were also evaluated.

MATERIALS AND METHODS

Three databases as well as the reference lists of included publications were searched using specified indexing terms. Publications that met the inclusion criteria were read and interpreted using pre-established protocols. Quality of evidence was classified according to the GRADE system (high, moderate, low, or very low).

RESULTS

The search yielded 2,130 titles and abstracts. Of these, the full-text versions of 488 publications were obtained. After data extraction and interpretation, 10 studies with moderate study quality of evidence and 1 study with low quality of evidence regarding outcomes, risks, and adverse effects remained. Three studies on the economic aspects of treatment were also included (1 with moderate quality and 2 with low quality). Low-quality evidence showed that the survival rate of implant-supported fixed prostheses is 95% after 5 years in patients with maxillary edentulism and 97% after 10 years in patients with mandibular edentulism. The survival rate of implant-supported overdentures is 93% after 5 years (low-quality evidence). In implant-supported fixed prostheses, 70 of every 1,000 implants are at risk of failing in the maxilla after 5 years and 17 of every 1,000 implants in the mandible are at risk after 10 years. Regarding economic aspects, the evidence was insufficient to provide reliable results.

CONCLUSIONS

Due to the low quality of evidence found in the included studies, further research with a higher quality of evidence is recommended to better understand the outcomes of treatment for patients with maxillary and/or mandibular edentulism.

Accuracy of virtually planned and template guided implant surgery on edentate patients

PURPOSE

Scientific evidence regarding the accuracy of implants placed into patients by the aid of a surgical template is limited. The objective of the present study was to verify if any variation exists between virtually planned implants' position using a computer, compared with the subsequently clinically placed implants with the aid of a surgical template in the mandible and the maxilla.

MATERIAL AND METHODS

A total number of 25 edentate jaws were treated with the aid of a surgical template. In total, 139 implants were inserted. Fifty implants were inserted in the mandible and 89 in the maxilla. A voxel-based registration method was used to match two separate cone-beam computed tomography scans of the patients. The implant positions were calculated and compared between the planned implants and the implants' clinical position after more than 1 year after surgery. The results included the linear differences in distance at the level of the hex, the apex, and the depth. The angular differences were presented in degrees.

RESULTS

Statistical results indicated some factors with significant deviations. The greatest errors were found when comparing between patients moving during the computed tomography scans and those that did not move. The results showed significant divergence at the level of the hex and apex of the implants.

CONCLUSION

The hypothesis was rejected, as the statistical results indicated that there were significant differences between virtually planned implants' position and the final position of implants placed clinically.

Perceived oral health in patients with Crohn's disease

PURPOSE

The aim of the present study was to investigate perceived oral health in patients with Crohn's disease (CD) in comparison with a control group without CD.

MATERIALS AND METHODS

The study population comprised 1943 patients with CD recruited from the Swedish National Patients Organisation of inflammatory bowel disease and 1000 randomly selected controls. All participants received a questionnaire with questions concerning socioeconomic variables, education, civil status, income, dental care habits, oral health and tobacco use.

RESULTS

Eighty-eight per cent of the patients and 75% of the controls answered the questionnaire. Patients with CD perceived their oral health to be worse than controls. The odds ratio (OR) for the patients to estimate their oral health as much worse than others in the same age group was 9.7 (95% CI, 5.8 to 16.4) after adjustment for age, smoking habit, gender and education. The patients also reported a significantly greater need for dental treatment than the controls, with an OR of 5.7 (95% CI, 4.2 to 7.9) after taking into account the age, smoking habit, gender and education. Furthermore, the patients with CD reported significantly more mouth-related problems than controls (OR 3.2), such as significantly more caries and more gingival bleeding. Of note, there were significantly more smokers in the patient group.

CONCLUSIONS

The results of the present study show that patients with CD perceived their oral health to be worse and have a greater need for dental treatment compared with the control group.

Treatment outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning and flapless surgery

OBJECTIVES

The objective was to evaluate the outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning combined with flapless surgery.

MATERIAL AND METHODS

Twenty-nine edentulous patients (9 females, 20 males, mean age of 71.5 years) were treated using the Nobel Guide protocol for surgical planning, fixture installation and immediate functioning of a prefabricated fixed implant prosthesis. One hundred and seventy-six fixtures were installed to support 21 maxillary and 10 mandibular reconstructions. Patients were followed for up to 44 months.

RESULTS

Nineteen out of 176 fixtures were lost between 2 and 18 months after installation. Fixture survival rate was 89% (92% maxilla, 83% mandible). Implant-supported suprastructures remained stable during the follow-up period in 26 out of 31 jaws (90% maxilla, 70% mandible). Surgical or technical complications occurred in 42% of treated cases. Misfit of abutment-bridge appeared in five cases, resulting in disconnection of the bridge in two patients where fixtures were left for unloaded healing. Fixture losses resulted in the removal of the suprastructure in three patients, who returned to removable dentures. Extensive adjustments of occlusion were made in 10% of the immediately connected bridges. Radiographic bone defects developed in three patients after drilling, which appeared in two cases after anchor-pin drilling in the maxilla and another in a severely resorbed mandible.

CONCLUSION

The patient's post-operative discomfort such as swelling and pain was almost negligible. However, compared to conventional protocols, the occurrences of surgical and technical complications were higher, and thus this method must still be regarded to be in an exploratory phase.

Supportive therapy and the longevity of dental implants: a systematic review of the literature

OBJECTIVE

To review systematically whether supportive implant treatment during a follow-up of at least 10 years after functional loading is effective in prevention of biological complications and fixture loss.

METHODS

A MEDLINE search was conducted for the period of 1965 to April 2006 of longitudinal clinical studies with follow-up periods after implant function of at least 10 years. Sixty-two studies were initially screened for inclusion and read in full text. Nine studies remained for the final assessment and 53 articles were thus excluded for the following reasons: (1) no information on implant maintenance was presented, (2) the number of patients/implants assessed at 10-year follow-up/final evaluation was not presented (3) fixture loss and marginal bone loss during function were not assessed at 10-year evaluation and (4) residual inflammation and/or probing pocket depth (PPD) not assessed at 10-year examination.

RESULTS

Fifty-six percent of 62 initially screened studies did not assess clinical inflammation and PPD around implants at long-term evaluation of implants. This was the most common reason for exclusion of studies. In 28% of excluded studies, there was no information on implant maintenance during follow-up. A total of 749 fixtures were included and followed for more than 10 years of functional load. Five of the included studies gave no detailed information of the assessments or the treatment at follow-up visits during the 10 years. Only in two of the included cohorts were patients enrolled in an individualized supportive program on a 3-6-month recall interval.

CONCLUSION

There are, to date, few available studies evaluating the long-term effect of supportive programs for implant patients. Based on the nine studies included, no evidence is available to suggest the frequency of recall intervals or to propose specific hygiene treatments. There is an urgent need for such studies to be initiated.

Peri-implantitis

The risk of developing peri-implantitis seems to be more pronounced in patients with a history of periodontitis. Pretreatment to eliminate periodontal pathogens from the patient's oral cavity before dental implant treatment therefore is important to reduce the risk of peri-implantitis. Smoking has been shown to be a negative risk factor for treatment success. Several protocols have been used in the treatment of peri-implantitis. Mechanical infection control following surgical flap procedures, particularly in conjunction with antimicrobial therapy, is the most successful concept. There is no reliable evidence that suggests which intervention is the most effective for treating peri-implantitis. This article includes background information on the biology of tissue-destructive periodontitis and peri-implantitis to help clinicians interpret the clinical manifestation of the risk for peri-implantitis.

Microbiological findings and host response in patients with peri-implantitis

The aim of the present study was to characterise microbiota and inflammatory host response around implants and teeth in patients with peri-implantitis. We included 17 partly edentulous patients with a total of 98 implants, of which 45 showed marginal bone loss of more than three fixture threads after the first year of loading. Nineteen subjects with stable marginal tissue conditions served as controls. Oral hygiene, gingival inflammation, and probing pocket depth were evaluated clinically at teeth and implants. Microbiological and crevicular fluid samples were collected from five categories of sites: 1) implants with peri-implantitis (PI), 2) stable implants (SI) in patients with both stable and peri-implantitis implants, 3) control implants (CI) in patients with stable implants alone, 4) teeth in patients (TP) and 5) controls (TC). Crevicular fluid from teeth and implants was analysed for elastase activity, lactoferrin and IL-1 beta concentrations. Elastase activity was higher at PI than at CI in controls. Lactoferrin concentration was higher at PI than at SI in patients with peri-implantitis. Higher levels of both lactoferrin and elastase activity were found at PI than at teeth in patients. The concentrations of IL-1 beta were about the same in the various sites. Microbiological DNA-probe analysis revealed a putative periodontal microflora at teeth and implants in patients and controls. Patients with peri-implantitis harboured high levels of periodontal pathogens, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus and Treponema denticola. These findings indicate a site-specific inflammation rather than a patient-associated specific host response.

Factors Affecting Late Fixture Loss and Marginal Bone Loss Around Teeth and Dental Implants

BACKGROUND

The predictability and high success rate of implant treatment have averted attention from factors affecting fixture loss and bone loss around implants.

PURPOSE

The goal of this study was to retrospectively evaluate late fixture loss and marginal bone loss around implants that have been in function for 5 years and to relate these findings to bone loss in the natural dentition.

MATERIALS AND METHODS

One hundred and forty-three consecutively treated patients who had received an implant-anchored fixed prosthesis and completed a 5-year follow-up were selected. Intraoral and panoramic radiographs were used to assess bone loss.

RESULTS

The bone loss was greater around remaining implants in patients who had lost implants after loading. No correlation was found between bone loss around implants and that around teeth. Only 2% of the fixtures were lost during 5 years of functional load. Most fixtures losses occurred in the edentulous maxilla. Seven of the nine patients who lost fixtures were smokers.

CONCLUSION

These findings show that patients who lost implants also lost more bone around the remaining implants. There was no correlation between bone loss around implants and that around teeth, indicating that different interacting mechanisms are involved.

Nutritional regulation of binding sites for lipoprotein lipase in rat heart

Several laboratories have shown that when rats are fasted, the amount of lipoprotein lipase (LPL) at the vascular endothelium in heart (monitored as the amount released by heparin) increases severalfold without corresponding changes in the production of LPL. This suggests that there is a change in endothelial binding of LPL. To study this, (125)I-labeled bovine LPL was injected. The fraction that bound in the heart was more than twice as high in fasted than in fed rats, 4.3% compared with 1.9% of the injected dose. Refeeding reversed this in 5 h. When unlabeled LPL was injected before the tracer, the fraction of (125)I-LPL that bound in heart decreased, indicating that the binding was saturable. When isolated hearts were perfused at 4 degrees C with a single pass of labeled LPL, twice as much bound in hearts of fasted rats. We conclude that fasting causes a change in the vascular endothelium in heart such that its ability to bind LPL increases.

Long-term evaluation of osseointegrated dental implants in the treatment of partly edentulous patients

AIM

The aim of this study was to evaluate the clinical, radiographic and microbiological status of implants after 10 years of functional load in patients treated for partial edentulism.

METHOD

15 patients, each successfully treated with 2-6 implants ad modum Brånemark placed in free-standing fixed prostheses, were included in the study.

RESULTS

Clinical evaluation revealed similar degrees of inflammation around teeth and implants. The probing pocket depth (PPD) was significantly greater around implants than around teeth. The mean marginal bone loss during 10 years of functional load was comparable to that found at the time of the 5-year follow-up. 74% of the implants remained free of marginal bone loss exceeding 1 mm. Marginal bone loss exceeding 2 mm, was found at only 5 sites. No marked differences in bacteria were present between teeth and implants. T. denticola, S. intermedia and P. micros were the commonest organisms detected around teeth and implants. The periodontal pathogens A. actinomycetemcomitans, P. gingivalis, P. intermedia, B. forsythus, and T. denticola, were found at implants with a marginal bone loss of more than 2 mm.

CONCLUSION

Our study shows that the long-term results with implants in partially dentate patients are similar to those seen in edentulous patients and that no significant change occurred after 5-year follow-up over an additional period of 5 years.

Chylomicron metabolism in an animal model for hyperlipoproteinemia type I

Mink homozygous for the mutation Pro214Leu in lipoprotein lipase (LPL) had only traces of LPL activity but amounts of LPL protein in their tissues similar to those of normal mink. In normal mink, lymph chylomicrons from rats given [3H]retinol (incorporated into retinyl esters, providing a core label) and [14C]oleic acid (incorporated mainly in triglycerides (TG)) were rapidly cleared from the circulation. In the homozygous mink, clearance was much retarded. The ratio of TG to core label in plasma did not decrease and much less [14C]oleic acid appeared in plasma. Still, half of the labeled material disappeared from the circulating blood within 30;-40 min and the calculated total turnover of TG in the hypertriglyceridemic mink was almost as large as in normal mink. The core label was distributed to the same tissues in hypertriglyceridemic mink as in normal mink. Half to two-thirds of the cleared core label was in the liver. The large difference was that in the hypertriglyceridemic mink, TG label (about 40% of the total amount removed) followed the core label to the liver and there was no preferential uptake of TG over core label in adipose or muscle tissue. In normal mink, only small amounts of TG label (<10%) appeared in the liver, while most was in adipose and muscle tissues. Apolipoprotein B-48 dominated in the accumulated TG-rich lipoproteins in blood of hypertriglyceridemic mink, even in fasted animals.

Conversion of chylomicrons into remnants

The turnover of chylomicrons in the blood is the sum of several processes. The native chylomicron is synthesized in the intestine out of available substrates. When the chylomicron enters the circulation exchanges of apolipoproteins with other lipoproteins, it also binds to the vascular endothelium where the chylomicron is lipolyzed by lipoprotein lipase. After a short period in the circulation the chylomicron/chylomicron remnant appears to be available for receptor mediated uptake. In this paper several of the processes involved in generation and clearance of chylomicron remnants are discussed.

Neutrophil response and microbiological findings around teeth and dental implants

The aim of this study was to compare the neutrophil response, measured as both functional and antigenic elastase, around teeth and titanium implants and to relate these findings to the microbiota. The 31 patients included in the study had been treated successfully for total or partial edentulism with titanium implants. Crevicular fluid and microbiological samples were taken from 3 sites: 1) crevices around teeth and 2) implants in 16 partially edentulous patients and 3) crevices around implants in 15 edentulous patients. All sites sampled showed similar degrees of inflammation assessed by gingival index and total protein concentration. The samples were analyzed for elastase activity and immunoreactive elastase. The elastase activity was significantly higher in crevices surrounding implants in partially edentulous patients compared with implants in edentulous patients. The antigenic elastase showed no difference among the 3 sites. Gram-positive cocci were the main bacterial species in all 3 groups. Edentulous patients tended to have lower frequency of black pigmenting anaerobes. No correlation of analyzed bacteria and elastase activity was found between the 3 sites. This study indicates that, despite a similar appearance of clinical parameters and absence of significant differences in the microbiota, the inflammation around implants in partially edentulous patients induces a stronger neutrophil response than does the inflammation around implants in edentulous patients.

Chylomicron/chylomicron remnant turnover in humans: evidence for margination of chylomicrons and poor conversion of larger to smaller chylomicron remnants

The size of cholesterol-rich lipoprotein particles is a strong determinant of whether they may be deposited in the arterial wall and by this become potentially atherogenic. This study deals with the in vivo transformation of larger-sized chylomicrons and chylomicron remnants to smaller-sized remnants. Twelve healthy men aged 22 to 45 years were given a fatty meal to which retinyl palmitate (RP) had been added. Plasmapheresis was performed 4 1/2 h after meal intake to isolate approximately 400 ml plasma. The RP-rich plasma was re-injected to the subject 24 h later. The RP content was determined in whole plasma and in Svedberg flotation rate fractions (Sf) > 400, Sf 60-400 and Sf 20-60. A compartmental model was developed for the kinetic analysis. Lipoprotein fractions showed minimal signs of aggregation, thus arguing for well-preserved postprandial lipoproteins. Approximately a fourth [23% (4-68%)] of the RP-containing lipoproteins in the Sf > 400 pool was converted to smaller species (Sf 60-400). Conversion of material from the Sf 60-400 to the Sf 20-60 fraction could not be detected. In a second study a large bolus dose of a triglyceride emulsion (Intralipid) was injected to subjects shortly after the RP-labeled plasma to investigate the endothelial binding of the chylomicron/chylomicron remnants. RP material in the Sf > 400 fraction rapidly returned to plasma, arguing for margination of chylomicrons, whereas the corresponding effect was minimal in the Sf 60-400 and Sf 20-60 fractions. The formation of small chylomicron remnants from the larger chylomicron/chylomicron remnant species is limited and large chylomicron/chylomicron remnants are not evenly distributed in plasma, rather they show signs of being marginated to the vascular endothelium.