Periodontitis in young individuals: Important factors for disease progression.

AIM: To investigate the progression of periodontitis in young individuals and identify factors that contribute to progression rate and whether periodontitis stage and grade have an impact on disease progression. MATERIALS AND METHODS: This retrospective cohort study was based on patients younger than 36 years at two periodontal clinics between 2003 and 2009. At least 10 years later, a clinical and radiographic examination was performed on 215 patients. The marginal bone loss between baseline and follow-up for the tooth with the most severe bone loss at follow-up was estimated by radiographic measurements. Linear regression analysis was used to investigate the influence of potential risk indicators on periodontitis progression. RESULTS: Most patients (83%) were classified as periodontitis stage III at baseline. At follow-up, 70% of these patients remained in stage III. The frequency of patients with grade C decreased from 79% to 17% at follow-up. The median (Q25%; Q75%) of the longitudinal marginal bone loss was 0.5 mm (0.0; 2.0). High bleeding on probing (BOP) index at baseline, smoking and interruption of periodontal treatment were found to significantly increase longitudinal bone loss. CONCLUSIONS: High levels of BOP at baseline, smoking and interruption of periodontal treatment increased the risk of marginal bone loss. The stage and grade at baseline had no significant impact on disease progression.

Prevalence of ongoing or previous SARS-CoV-2 infection among dental personnel - the Swedish experience.

CONCLUSIONS: The seroprevalence of SARS-CoV-2 infection was approximately similar to that in healthcare personnel, and approximately equal compared to that in the general population. MATERIALS AND METHODS: We carried out an observational cohort study from March to June 2020, including 341 employees randomly selected from Public Dental Service in the County of Stockholm. The primary outcome variable was the prevalence of SARS-CoV-2 RNA and/or antibodies against SARS-CoV-2. Throat samples were analysed for SARS-CoV-2 RNA. Venous blood was collected to detect antibodies against SARS-CoV-2 using the Luminex analysis tool (immunoassay) and ELISA. Logistic regression analysis was used to compare the independent groups and calculate the unadjusted odds ratio. OBJECTIVE: To investigate whether personnel in a public dental clinic had a higher frequency of ongoing or previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than hospital healthcare workers or the general public in Stockholm during weeks 23-25 in 2020. RESULTS: The mean age of the participants was 50.1 years, and 11.7% were male. The prevalence of SARS-CoV-2 RNA and/or antibodies against SARS-CoV-2 was 12.0% (95% confidence interval 8.8-16.0). Among them, 82.5% reported symptoms and 85.4% were on sick-leave between March and June 2020.

Radiographic peri-implant bone loss after a function time up to 15 years.

OBJECTIVE: The aim was to assess the degree of radiographic peri-implant bone loss over a follow-up period up to 15 years. In addition, another aim was to identify risk indicators for peri-implant bone loss and for moderate-severe peri-implantitis at patient- and implant level. MATERIALS AND METHODS: This is a cross-sectional clinical and radiological study of 147 patients with a total of 425 implants in combination with data collected retrospectively for baseline variables. To calculate the peri-implant bone loss (primary outcome variable), the radiographic bone level measurements from baseline were compared to the radiographic bone level measurements at the final radiographic measurement. Multilevel analyses were adopted with peri-implant bone loss and peri-implantitis as outcome variables. RESULTS: The mean follow-up time was 12.5 years (range 10-15) and the mean age of the patients was 63 years (range 29-83). The mean peri-implant bone loss was 0.94 mm (S.D. 1.3). The prevalence of moderate-severe peri-implantitis at patient level was 17% and 8.9% at implant level. The peri-implant bone loss was significantly more pronounced in healthy implants if moderate-severe peri-implantitis was present in at least one implant within the same patient. The presence of moderate-severe peri-implantitis was significantly associated with general periodontitis Stages III or IV at follow-up and smoking. CONCLUSION: The presence of moderate-severe peri-implantitis at patient level was found to be a risk indicator of peri-implant bone loss in healthy implants, while smoking and general periodontitis Stages III and IV were risk indicators of moderate-severe peri-implantitis.

Intra-individual cytokine profile in peri-implantitis and periodontitis: A cross-sectional study.

AIM: To study cytokine profiles and intra-individual correlations in crevicular fluid samples at periodontitis, peri-implantitis, and healthy sites. MATERIALS AND METHODS: Samples from gingival crevicular fluid (GCF) and peri-implant crevicular fluid (PICF) were collected from healthy and diseased sites in patients who had had dental implants for a minimum of 10 years. Cytokine levels were analyzed using the Bio-Plex Pro Human inflammation kit, which included biomarkers for the tumor necrosis factor-α (TNF-α) superfamily, regulatory T Cell (Treg) cytokines, and interferon (IFN) proteins. RESULTS: Gingival crevicular fluid/PICF cytokine levels, determined in samples from 163 patients, were frequently lower for healthy tooth and implant sites compared to sites with periodontitis or peri-implantitis. In contrast, there were no significant differences in cytokine levels between peri-implant sites and periodontitis sites. Intra-individual correlations between cytokines at peri-implant sites were frequently significant. In addition, the cytokines IFN-λ1 and TNFSF12 were significantly correlated with the presence of peri-implantitis. CONCLUSION: Within the limits of this study, the intra-individual cytokine profile did not differ between sites diagnosed with periodontitis and those diagnosed with peri-implantitis, but did differ between healthy tooth and healthy implant sites. Studying intra-individual cytokine profiles is a method to elucidate possible differences between the etiopathogeneses of periodontitis and peri-implantitis, since it is well known that immune responses to dysbiosis vary between individuals according to host factors. Thus, the findings of the present study are potentially relevant to the advancement of knowledge in this field.

Survival rate after endodontic treatment in general dentistry for cracked teeth with different coronal restorations.

OBJECTIVE: The aim of this study was to analyse the survival rate of cracked teeth after endodontic treatment. The secondary aim was to compare the survival rate of cracked teeth restored with composite filling/crown and those restored with a full crown. MATERIALS AND METHODS: The study was conducted retrospectively from three general dental clinics in Stockholm, which are all part of the national dental service organisation. Two-hundred patients with teeth receiving endodontic treatment due to symptomatic cracks were included. The patient data range from year 2001 to 2016. RESULTS: The mean age of the patients was 48 years (range 29-69). Fifty-five per cent had cracks located above the pulpal cavity, 11% within the pulpal cavity and 3% located in the root canal. The cracks were located most commonly on the proximal surfaces. The survival rate for teeth with cracks was 68% and 54% after 5 and 10 years, respectively. The survival rate was significantly higher (97%) for cracked teeth receiving a full crown after endodontic treatment compared to teeth restored with either a composite filling or composite crown. CONCLUSION: The overall survival rate for cracked teeth was 68% after 5 years, while it was significantly higher for cracked teeth restored with a full crown. The results suggest within the limitations of this study that cracked teeth should be restored with a full crown after endodontic treatment.

Survival of root filled teeth in general dentistry in a Swedish county: a 6-year follow-up study.

OBJECTIVE: The purpose of the present study was to investigate the survival rate of root filled teeth in general dentistry in a Swedish county and to identify risk predictors with a significant influence on the survival rate. MATERIALS AND METHODS: This is a retrospective 6-year follow-up study on 1642 recall patients with 1720 teeth root filled in general dentistry in the Public Dental Service in the county of Stockholm, Sweden. Background variables were collected from the database at baseline as potential predictors of tooth loss. The outcome variables were extraction during the 6-year follow-up period and the reason for the extraction. Stepwise Cox regression analysis was adopted in order to investigate the influence of the potential risk predictors on the risk for tooth extraction. RESULTS: Nine percent of the root filled teeth were lost after 6 years. The most frequent reason for tooth loss was fracture and/or cracks (58%). The survival rate of the root filled teeth increased significantly for younger patients, root filled teeth with metal crowns (96%) and high quality of the root filling (93%). The survival rate differed significantly between tooth groups with the lowest survival for molars (83%). Composite fillings were significantly associated with lower quality of the root fillings. CONCLUSIONS: Ninety-one percent of the root filled teeth survived after 6 years. The survival rate was significantly higher for teeth with root-fillings of high quality and metal crowns as well as for root filled teeth in younger patients. The lowest survival rate was found for molars.

Survival and complications: A 9- to 15-year retrospective follow-up of dental implant therapy.

Long-term follow-up of oral implant therapy seldom report all biological and technical complications. The objective of this study was to evaluate the long-term (9-15 years) outcome after dental implant therapy, assess survival and complication rates. In addition, to identify the risk indicators of these complications at patient and implant levels. Patients (n = 376) treated with dental implants (n = 1095) between 1999 and 2005 at a specialist clinic in Stockholm, Sweden, were included. Longitudinal data were collected retrospectively from digital dental records. A subset of the included patient underwent a clinical examination at the 9-15 years follow-up (n = 163). Chi-square tests, Kaplan-Meier analyses and the general estimating equations (GEE) procedure were adopted for multilevel analyses. The cumulative implant survival rate up to 15 years was 82.6% (SE 4.1%). The prevalences of biological and technical complications at patient level were 52% and 32%, respectively. In total, 763 complications occurred, 65% of patients experienced at least one complications. Implant loss occurred significantly more frequently in subjects with a history of treated severe periodontitis Stage III-IV (P = .008) and in cases when complications were registered during implant surgery (P = .010). Smoking was a significant risk indicator for peri-implantitis (P = .006). The long-term implant survival and complication rates at patient level were 83% and 79%, respectively. Implant loss was significantly more frequent for subjects with a history of treated severe periodontitis and if complication was registered during implant surgery. Smoking was a significant risk indicator for peri-implantitis.

Mortality rate and oral health - a cohort study over 44 years in the county of Stockholm.

OBJECTIVE: To study the association between oral health and all-cause mortality rate over 44 years. In addition, the specific relations between oral health and death caused by cardiovascular disease (CVD), cancer or other reasons were investigated. MATERIALS AND METHODS: An epidemiological investigation studying the oral health of the population consisting of 1393 randomly selected subjects was performed in the County of Stockholm. The individuals were invited to a clinical examination, an interview and a radiographic examination. The incidence of mortality during the years 1970-2014 as well as the causes of death according to the death certificate were registered in 2015. Cox regression survival analysis was used for investigating the effect of several variables upon the time to the outcome of death. RESULTS: Forty-six percent of the subjects were still alive at the end of the year 2014. Cancers caused 27% of the deaths, while 22% died due to CVD. The mortality risk was positively and significantly correlated to oral health when compensated for age, sex, smoking and social status. In addition, the mortality risk caused by CVD, cancer or other reasons was significantly increased for those with poor oral health. CONCLUSIONS: Oral health was found to be a risk indicator of death caused by CVD and cancer as well as for all-cause mortality. Thus, the associations are unspecific. Harmful lifestyle factors impact dental health behavior as well as mortality risk. This might contribute to the association between oral health and mortality risk.

Mucin 4 and matrix metalloproteinase 7 as novel salivary biomarkers for periodontitis.

AIM: Periodontitis is a chronic inflammatory disease, characterized by irreversible destruction of tooth-supporting tissue including alveolar bone. We recently reported mucin 4 (MUC4) and matrix metalloproteinase 7 (MMP7) as highly associated with periodontitis in gingival tissue biopsies. The aim of this study was to further investigate the levels of MUC4 and MMP7 in saliva and gingival crevicular fluid (GCF) samples of patients with periodontitis. MATERIALS AND METHODS: Saliva and GCF samples were collected from periodontitis patients and healthy controls. The levels of MUC4, MMP7, and total protein concentrations were analysed using ELISA or Bradford assay. RESULTS: MUC4 levels were significantly lower in saliva and GCF from periodontitis patients relative to healthy controls. MMP7 levels were significantly higher in saliva and GCF from periodontitis patients. Multivariate analysis revealed that MUC4 was significantly associated with periodontitis after adjusting for age and smoking habits and, moreover, that the combination of MUC4 and MMP7 accurately discriminated periodontitis from healthy controls. CONCLUSIONS: MUC4 and MMP7 may be utilized as possible novel biomarkers for periodontitis.

Treatment compliance in patients with aggressive periodontitis - a retrospective case-control study.

OBJECTIVE: To investigate if differences according to discontinuation of treatment could be identified between patients with aggressive periodontitis and chronic periodontitis at two specialist clinics of periodontology irrespective of the effects of background factors. MATERIALS AND METHODS: This is a retrospective case-control study. The variables were registered from dental records. The population consisted of patients referred to two specialist clinics of periodontology during three years. A study group was included consisting of 234 patients with a diagnosis of aggressive periodontitis. A control group with a diagnosis of chronic periodontitis was randomly selected. RESULTS: In total, 234 patients (4% of the referrals) with a diagnosis of aggressive periodontitis were referred to the two periodontal clinics during a period of three years. Forty-two per cent of the non-compliant patients were smokers compared to 31% for the compliers and this difference was statistically significant. Patients with aggressive periodontitis interrupted their periodontal treatment significantly more frequently (46%) compared to those patients with chronic periodontitis (34%). The non-compliant patients had significantly deeper periodontal pockets at baseline as well as significantly more sites with bleeding at probing. In a stepwise logistic regression analysis, aggressive periodontitis, smoking and the relative frequency of sites with periodontal pockets >4 mm at baseline were the remaining variables with a significant influence on the incidence of interrupting ongoing periodontal treatment. CONCLUSIONS: The patient group with aggressive periodontitis interrupted the periodontal treatment significantly more often irrespective of background factors and risk factors, which may be regarded as a major health problem.

Pancreatic perfusion and subsequent response to glucose in healthy individuals and patients with type 1 diabetes.

AIMS/HYPOTHESIS: The aim of this study was to investigate pancreatic perfusion and its response to a glucose load in patients with type 1 diabetes mellitus compared with non-diabetic ('healthy') individuals. METHODS: Eight individuals with longstanding type 1 diabetes and ten sex-, age- and BMI-matched healthy controls underwent dynamic positron emission tomography scanning with (15)O-labelled water before and after intravenous administration of glucose. Perfusion in the pancreas was measured. Portal and arterial hepatic perfusion were recorded as references. RESULTS: Under fasting conditions, total pancreatic perfusion was on average 23% lower in the individuals with diabetes compared with healthy individuals. Glucose increased total pancreatic and portal hepatic blood perfusion in healthy individuals by 48% and 38%, respectively. In individuals with diabetes there was no significant increase in either total pancreatic or portal hepatic perfusion. CONCLUSIONS/INTERPRETATION: Individuals with type 1 diabetes have reduced basal pancreatic perfusion and a severely impaired pancreatic and splanchnic perfusion response to intravenous glucose stimulation.

Effects by periodontitis on pristane-induced arthritis in rats.

BACKGROUND: An infection-immune association of periodontal disease with rheumatoid arthritis has been suggested. This study aimed to investigate the effect of pre-existing periodontitis on the development and the immune/inflammatory response of pristane-induced arthritis. METHODS: We investigated the effect of periodontitis induced by ligature placement and Porphyromonas gingivalis (P. gingivalis) infection, in combination with Fusobacterium nucleatum to promote its colonization, on the development of pristane-induced arthritis (PIA) in rats (Dark Agouti). Disease progression and severity of periodontitis and arthritis was monitored using clinical assessment, micro-computed tomography (micro-CT)/intraoral radiographs, antibody response, the inflammatory markers such as α-1-acid glycoprotein (α-1-AGP) and c-reactive protein (CRP) as well as cytokine multiplex profiling at different time intervals after induction. RESULTS: Experimentally induced periodontitis manifested clinically (P < 0.05) prior to pristane injection and progressed steadily until the end of experiments (15 weeks), as compared to the non-ligated arthritis group. Injection of pristane 8 weeks after periodontitis-induction led to severe arthritis in all rats demonstrating that the severity of arthritis was not affected by the pre-existence of periodontitis. Endpoint analysis showed that 89% of the periodontitis-affected animals were positive for antibodies against arginine gingipain B and furthermore, the plasma antibody levels to a citrullinated P. gingivalis peptidylarginine deiminase (PPAD) peptide (denoted CPP3) were significantly (P < 0.05) higher in periodontitis rats with PIA. Additionally, there was a trend towards increased pro-inflammatory and anti-inflammatory cytokine levels, and increased α-1-AGP levels in plasma from periodontitis-challenged PIA rats. CONCLUSIONS: Pre-existence of periodontitis induced antibodies against citrullinated peptide derived from PPAD in rats with PIA. However, there were no differences in the development or severity of PIA between periodontitis challenged and periodontitis free rats.

Effectiveness of Early Preventive Intervention with Semiannual Fluoride Varnish Application in Toddlers Living in High-Risk Areas: A Stratified Cluster-Randomized Controlled Trial.

This study evaluated whether toddlers in an extended preventive program of semiannual fluoride varnish applications from 1 year of age had a lower incidence of caries than those undergoing a standard program. A cohort of 1-year-old children (n = 3,403) living in multicultural areas of low socioeconomic standing in Stockholm participated in a cluster-randomized controlled field trial with two parallel arms. The children attended 23 dental clinics. Using the ICDAS II criteria, the examiners recorded caries at baseline and after 1 and 2 years. The children in the reference group received a standardized oral health program once yearly between 1 and 3 years of age. The children in the test group received the same standard program supplemented with topical applications of fluoride varnish every 6 months. We compared the test group and the reference group for the prevalence and increment of caries. At baseline, 5% of the children had already developed caries (ICDAS II 1-6). We reexamined the children after 1 year (n = 2,675) and after 2 years (n = 2,536). Neither prevalence nor caries increment differed between the groups. At 3 years of age, 12% of the children had developed moderate and severe carious lesions (ICDAS II 3-6), with a mean increment of 0.5 (SD 2.4) in the test group and 0.6 (SD 2.2) in the reference group. In conclusion, semiannual professional applications of fluoride varnish, as a supplement to a standard oral health program, failed to reduce caries development in toddlers from high-risk communities.

Patient satisfaction 8-14 years after dental implant therapy - a questionnaire study.

OBJECTIVE: The aim of this questionnaire study was to investigate patient satisfaction 8-14 years after dental implant therapy and complications influencing the degree of satisfaction. MATERIALS AND METHODS: A questionnaire was sent by post to 587 patients at a specialist clinic of periodontology. The questionnaire consisted of 19 statements or questions such as the degree of satisfaction with the implants and knowledge of complications. In nine of the questions, respondents were asked to grade the extent of their agreement with a statement by selecting from fixed answers. Three of the questions were designed to be answered using a visual analog scale. RESULTS: In total, 400 individuals (81%) responded to the questionnaire. The mean time elapsed since implant installation was 10 years. A great majority (81%) experienced a high chewing comfort and was satisfied or sufficiently satisfied (94%) with the aesthetic aspects of their implant restorations, while 32% of the individuals had experienced problems with their implant reconstructions. The disadvantage that patients remarked on was the cost of the treatment. Those who had experienced problems with their implant reconstructions were also less satisfied with the treatment. CONCLUSION: A great majority of the patients expressed a high degree of satisfaction with their dental implants 8-14 years after the treatment. Patients were less satisfied if they had experience of problems with their implant reconstructions and in cases when the clinicians were unable to resolve their complications.

Abrogation of adenosine A1 receptor signalling improves metabolic regulation in mice by modulating oxidative stress and inflammatory responses.

AIMS/HYPOTHESIS: Adenosine is an important regulator of metabolism; however, the role of the A1 receptor during ageing and obesity is unclear. The aim of this study was to investigate the effects of A1 signalling in modulating metabolic function during ageing. METHODS: Age-matched young and aged A 1 (also known as Adora1)-knockout (A1(-/-)) and wild-type (A1(+/+)) mice were used. Metabolic regulation was evaluated by body composition, and glucose and insulin tolerance tests. Isolated islets and islet arterioles were used to detect islet endocrine and vascular function. Oxidative stress and inflammation status were measured in metabolic organs and systemically. RESULTS: Advanced age was associated with both reduced glucose clearance and insulin sensitivity, as well as increased visceral adipose tissue (VAT) in A1(+/+) compared with A1(-/-) mice. Islet morphology and insulin content were similar between genotypes, but relative changes in in vitro insulin release following glucose stimulation were reduced in aged A1(+/+) compared with A1(-/-) mice. Islet arteriolar responses to angiotensin II were stronger in aged A1(+/+) mice, this being associated with increased NADPH oxidase activity. Ageing resulted in multiple changes in A1(+/+) compared with A1(-/-) mice, including enhanced NADPH oxidase-derived O2(-) formation and NADPH oxidase isoform 2 (Nox2) protein expression in pancreas and VAT; elevated levels of circulating insulin, leptin and proinflammatory cytokines (TNF-α, IL-1ß, IL-6 and IL-12); and accumulation of CD4(+) T cells in VAT. This was associated with impaired insulin signalling in VAT from aged A1(+/+) mice. CONCLUSIONS/INTERPRETATION: These studies emphasise that A1 receptors regulate metabolism and islet endocrine and vascular functions during ageing, including via the modulation of oxidative stress and inflammatory responses, among other things.

The use of hydrogen gas clearance for blood flow measurements in single endogenous and transplanted pancreatic islets.

The blood perfusion of pancreatic islets is regulated independently from that of the exocrine pancreas, and is of importance for multiple aspects of normal islet function, and probably also during impaired glucose tolerance. Single islet blood flow has been difficult to evaluate due to technical limitations. We therefore adapted a hydrogen gas washout technique using microelectrodes to allow such measurements. Platinum micro-electrodes monitored hydrogen gas clearance from individual endogenous and transplanted islets in the pancreas of male Lewis rats and in human and mouse islets implanted under the renal capsule of male athymic mice. Both in the rat endogenous pancreatic islets as well as in the intra-pancreatically transplanted islets, the vascular conductance and blood flow values displayed a highly heterogeneous distribution, varying by factors 6-10 within the same pancreas. The blood flow of human and mouse islet grafts transplanted in athymic mice was approximately 30% lower than that in the surrounding renal parenchyma. The present technique provides unique opportunities to study the islet vascular dysfunction seen after transplantation, but also allows for investigating the effects of genetic and environmental perturbations on islet blood flow at the single islet level in vivo.

A double-blind randomized study evaluating the effect of intra-alveolar chlorhexidine gel on alveolar osteitis after removal of mandibular third molars.

PURPOSE: The main purpose of the present investigation was to determine whether intra-alveolar chlorhexidine (CHX) gel is an effective preventative treatment for alveolar osteitis (AO), as has been strongly suggested by previous investigators. Another goal was to evaluate whether there is a correlation between the use of analgesics during the postoperative week and the development of AO, a correlation that could be a supplement to the commonly used diagnostic criteria for AO. MATERIALS AND METHODS: A double-blinded randomized study was performed to assess whether intra-alveolar administration of CHX decreases AO. To achieve this objective, the extraction and postoperative course of 100 impacted mandibular third molars were studied. Ninety-seven percent of teeth operated on had a diagnosed pathology. The extraction alveoli were treated with CHX or placebo. The intake of analgesics was recorded for 7 days after the operation. RESULTS: Statistically important differences in AO between the control and experimental groups were not found. The intake of analgesics reflected the occurrence of AO with a high degree of importance. CONCLUSION: The present study did not verify that application of CHX gel improves healing after removal of impacted third molars. The patients' postoperative analgesic intake reflected the development of AO.

Relationship between apical periodontitis and marginal bone loss at individual level from a general population.

AIM: To study the relationship between the presence of apical periodontitis in root-filled teeth and marginal bone loss (MBL) in individual subjects from a general population. MATERIALS AND METHODS: The study was conducted on a sample of 1,152 dentate individuals (participants in an epdemiological investigation) who were subjected to clinical and radiographic investigations. The presence of root fillings and apical periodontitis were registered. MBL was measured mesially and distally at all roots. The MBL index of the subject was defined as the mean MBL value at all measurable points in the same individual. Multiple regression analysis was adopted to calculate the influence of the presence of apical periodontitis and potential confounders on the dependent variable, MBL index. RESULTS: There was a significant correlation between MBL and the percentage of root-filled teeth and the percentage of root-filled teeth with apical periodontitis. The results of the multiple regression analysis showed that the relative frequency of root-filled teeth with apical periodontitis was significantly higher in subjects with more MBL, irrespective of age, number of remaining teeth, relative frequency of root-filled teeth and smoking habits. CONCLUSIONS: A significant association between the presence of apical and marginal periodontitis in individual subjects was found. The mechanisms behind the associations between these diseases are unknown and this cross-sectional observational study did not permit distinction between cause and effect. It is hoped that future cohort studies may provide more knowledge about the biological actions behind the relationship between apical and marginal disease.

The influence of immigrant background on the choice of sedation method in paediatric dentistry.

The effects of immigration on the demographics of the Swedish population have changed the situation for many dental care providers, placing increased demand on cultural competence. The aim of this investigation was to study the choice of sedation method among children with immigrant background, referred to paediatric dentistry specialists, because of behaviour management problems or dental fear in combination with treatment needs. The material consisted of dental records from children referred to two clinics for paediatric dentistry: 117 records from children with an immigrant background and 106 from children with a non-immigrant background. Information about choice of sedation method (conventional treatment, conscious sedation with midazolam, nitrous oxide, or general anaesthesia) and dental status was collected from the records. The number of missed appointments (defaults) was also registered. Binary logistic regression analyses were used to calculate the influence of potential predictors on choice of sedation method. The mean age of the patients in the immigrant group was 4.9 yrs, making them significantly younger than the patients in the non-immigrant group (mean 5.7 yrs). In the immigrant group, 26% of the patients defaulted from treatments, while the corresponding frequency was significantly lower for the reference group (7%). The numbers of primary teeth with caries and permanent teeth with caries were positively and significantly correlated with the choice of treatment under general anaesthesia. Conscious sedation was used significantly more often in younger children and in the non-immigrant group, while nitrous oxide was preferred in the older children. In conclusion, conscious sedation was more frequently used in the non-immigrant group. The choice of sedation was influenced by caries frequency and the age of the child.

Blood lipids affect rat islet blood flow regulation through ß3-adrenoceptors.

Pancreatic islet blood perfusion varies according to the needs for insulin secretion. We examined the effects of blood lipids on pancreatic islet blood flow in anesthetized rats. Acute administration of Intralipid to anesthetized rats increased both triglycerides and free fatty acids, associated with a simultaneous increase in total pancreatic and islet blood flow. A preceding abdominal vagotomy markedly potentiated this and led acutely to a 10-fold increase in islet blood flow associated with a similar increase in serum insulin concentrations. The islet blood flow and serum insulin response could be largely prevented by pretreatment with propranolol and the selective ß3-adrenergic inhibitor SR-59230A. The nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester prevented the blood flow increase but was less effective in reducing serum insulin. Increased islet blood flow after Intralipid administration was also seen in islet and whole pancreas transplanted rats, i.e., models with different degrees of chronic islet denervation, but the effect was not as pronounced. In isolated vascularly perfused single islets Intralipid dilated islet arterioles, but this was not affected by SR-59230A. Both the sympathetic and parasympathetic nervous system are important for the coordination of islet blood flow and insulin release during hyperlipidemia, with a previously unknown role for ß3-adrenoceptors.