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Speech impairments are an early feature of Alzheimer's disease (AD) and consequently, analysing speech performance is a promising new digital biomarker for AD screening. Future clinical AD trials on disease modifying drugs will require a shift to very early identification of individuals at risk of dementia. Hence, digital markers of language and speech may offer a method for screening of at-risk populations that are at the earliest stages of AD, eventually in combination with advanced machine learning. To this end, we developed a screening battery consisting of speech-based neurocognitive tests. The automated test performs a remote primary screening using a simple telephone.PROSPECT-AD aims to validate speech biomarkers for identification of individuals with early signs of AD and monitor their longitudinal course through access to well-phenotyped cohorts.PROSPECT-AD leverages ongoing cohorts such as EPAD (UK), DESCRIBE and DELCODE (Germany), and BioFINDER Primary Care (Sweden) and Beta-AARC (Spain) by adding a collection of speech data over the telephone to existing longitudinal follow-ups. Participants at risk of dementia are recruited from existing parent cohorts across Europe to form an AD 'probability-spectrum', i.e., individuals with a low risk to high risk of developing AD dementia. The characterization of cognition, biomarker and risk factor (genetic and environmental) status of each research participants over time combined with audio recordings of speech samples will provide a well-phenotyped population for comparing novel speech markers with current gold standard biomarkers and cognitive scores.N= 1000 participants aged 50 or older will be included in total, with a clinical dementia rating scale (CDR) score of 0 or 0.5. The study protocol is planned to run according to sites between 12 and 18 months.The speech protocol includes the following neurocognitive tests which will be administered remotely: Word List [Memory Function], Verbal Fluency [Executive Functions] and spontaneous free speech [Psychological and/ or behavioral symptoms]. Speech features on the linguistic and paralinguistic level will be extracted from the recordings and compared to data from CSF and blood biomarkers, neuroimaging, neuropsychological evaluations, genetic profiles, and family history. Primary candidate marker from speech will be a combination of most significant features in comparison to biomarkers as reference measure. Machine learning and computational techniques will be employed to identify the most significant speech biomarkers that could represent an early indicator of AD pathology. Furthermore, based on the analysis of speech performances, models will be trained to predict cognitive decline and disease progression across the AD continuum.The outcome of PROSPECT-AD may support AD drug development research as well as primary or tertiary prevention of dementia by providing a validated tool using a remote approach for identifying individuals at risk of dementia and monitoring individuals over time, either in a screening context or in clinical trials.

There is a methodological problem in analysis of data belonging to different hierarchical levels, e.g. patient, arch, and tooth. A method for multilevel modelling (MLM) that resolves this problem is available. This method which is presented in this article, was used to reanalyse previously published long-term treatment results concerning the longevity of fixed partial dentures, retainers and abutments. The main results were consistent, indicating that no great faults were committed when using the conventional logistic regression method. There were, however, differences when calculating the combined risks for various situations. The conventional method was found to over- and underestimate probabilities of survival in different cases, compared to the MLM method. Especially when the most negative factors were combined, the conventional method had a tendency to underestimate the risk. For example, if an abutment had the combination 'endodontically treated'; 'FPD placed by 'another dentist''; 'distal abutment'; and 'marginal bone loss > 50%'; the probability of the tooth remaining after 18-23 years was only 20% according to the MLM method but 35% according to the conventional method. It was concluded that MLM is the method of choice for many situations in dental research where data belonging to different levels are to be analysed.

OBJECTIVE To evaluate the accuracy of the detailed narrow-beam (DNB) technique with the Scanora multimodal X-ray unit for the assessment of dental implants in severely resorbed maxillae as an alternative to conventional intra-oral radiography. METHODS The DNB technique was used in 15 consecutive patients with maxillary overdentures supported by implants in the canine regions. Both conventional intra-oral radiographs and DNB radiographs were also obtained for a further 15 consecutive patients with maxillary fixed prostheses on implants in the canine region. The marginal bone height was scored in relation to the threads on the implants. RESULTS Intra-observer agreement was 95%. There was an 84% agreement between the two radiographic methods: the difference was at most one thread and was not significant (p = 0.43). CONCLUSIONS The DNB technique is an accurate alternative when conventional intra-oral techniques cannot be used properly.

The aim of the present study was to evaluate clasp-retained removable partial dentures (RPDs) made in the Public Dental Health Service (PDHS) in Orebro County in 1989. Records from all 25 PDHS clinics concerning RPDs from 1989 were collected after eight years and available information was registered. The entire material consisted of 447 RPDs (both attachment-retained and clasp-retained RPDs) in 387 patients. Of the 316 clasp-retained RPDs that were traceable, 208 were followed from 1989 to 1997. In most instances, information on diagnoses, alternative treatments and design of the RPDs was lacking. One hundred and thirty-two (42%) of the 316 clasp-retained RPDs were judged to still be in use in 1997 while 75 were not in use. The main reason for ceased use was dislike by the patient. There were 108 clasp-retained RPDs that were not possible to follow from 1989 to 1997 because there were no notes regarding follow-ups in the records. The most common technical complications noted in the records during the observation period were clasp fractures and loosened artificial teeth.

To evaluate the influence of two different dental care systems on dental status, taking into account relevant socio-economic factors.Questionnaire studies on randomly sampled subjects in Denmark and Sweden using questionnaire forms as identical as possible with regard to the different languages.The studies were performed late in 1998 in both countries.Questionnaires were sent to 1,175 subjects aged 45-69 years in Denmark (response rate 73%) and to 1,001 subjects aged 55-79 years in Sweden (response rate 67%).Questions about dental status and about socioeconomic factors and attitudes toward dental care were included. In logistic regression models, various dichotomies of dental conditions were used as dependent variables. State (Denmark vs. Sweden) was used as an independent variable together with socioeconomic factors and attitudes.There were great differences between the countries in dental status. In the regression model with 'wearing removable denture(s)' as the dependent variable, state was the strongest predictor with an OR of above 4.1 for Denmark compared to Sweden. much stronger than variables such as age, income, education and residence.The results indicate that the Swedish dental care system has been superior to the Danish one regarding dental status in middle aged and older populations in these two countries.

The purpose of this study was to describe how dentists evaluated the importance of various items related to a treatment choice between fixed partial dentures (FPD) and single implants, and to analyze if the differences could be explained by dentist-related variables such as social and demographic attributes, job situation, and attitudes.Questionnaires were sent to a random sample of 2,059 Swedish general dentists, with a response rate of 76%. In the questionnaire, the choice between an FPD and a single-implant restoration in a clinical situation was presented. Fifteen items were constructed and the dentists were asked to mark on visual analogue scales the relative importance he or she gave the different items. The items were analyzed through principal components analysis, where a three-factor solution was obtained; the factors were labeled as "time," "health," and "comfort." The factors were run as dependent variables in multiple regression analyses.The items evaluated as most important were "prognosis for delivered treatment" and "patient's wish." Large individual differences were seen, but the differences between groups of dentists were small. Male dentists considered the "health" and the "comfort" factors to be more important compared to female dentists. The attitudinal variable "patient information" was significantly associated with the "time" factor and, inversely, with the "comfort" factor.Differences between individuals were great, but between groups of dentists the differences were only minor. Multivariately, the attitudinal variable "patient information" showed significant associations with the "time" and the "comfort" factors. Dentist-related variables explained little of the variations. The results further indicated a low personal knowledge concerning implant treatments. Psychologic methods might explain more of the individual differences in prosthodontic decision making, but these are not easily used in a questionnaire study.

This study described and explored verbal communication during prosthodontic treatment.Sixty-one patients and 15 dentists participated. Sixty-one prosthetic treatment periods, during which fixed tooth- or implant-supported prostheses were placed, were followed. One visit during each treatment period was audio recorded. The recorded verbal communication was analyzed with the Roter Interaction Analysis System-dental. The inter-rater reliability was 95% to 97% for utterance classification and kappa = 0.71 to 0.78 for categorization definition.There were 43,663 utterances available for analysis. Of those, 59% was dentist communication, 28% was patient communication, and 10% was dental nurse communication. Other persons, e.g., dental technicians, contributed with 3%. The dentist-patient communication contained more task-focused than socioemotional behaviors. Female patients used socioemotional talk to a greater extent than did the male patients. Dentists and patients of different genders communicated more overall, especially male dentists with female patients. The age difference between dentist and patient had no effect on the amount or type of communication. The dental nurse talked slightly more with male patients.When different genders met there was more communication, and the talk was more socioemotional when the patient was female.

This study examined whether it is possible to restore an edentulous mandible with a complete-arch fixed prosthesis retained by only 4 implants without decreasing the survival rate. One hundred nineteen patients received complete-arch mandibular prostheses retained by 4 implants. Most patients were followed for 3 years or more. All patients followed a routine protocol, including annual check-ups and regular radiographic examinations. Twenty-one patients dropped out. Radiographic measurements used the threads of the implants as a basis for comparison. No indication was found that the number of supporting implants could have influenced the observed frequency of technical and surgical complications. Three implants were lost, 2 after 1 year and 1 after 5 years. A statistically significant difference in bone loss between the mesial and distal implants was found. The number of fractured resin teeth in mandibular prostheses was higher when patients had an implant-supported prosthesis in the maxilla. The present study revealed an implant survival rate of 98.6% after 5 years. Therefore, it was concluded that there may not be a need for more than 4 implants to support a fixed mandibular prosthesis, when implants at least 10 mm long can be used.

To evaluate, using multivariate methods, the associations between indicators of the amount of prosthodontic treatment and dentist-related factors.Questionnaires were sent to a random sample of 2,059 general dentists, response rate was 76%. Two indicators of prosthodontic activity were used as dependent variables: 1) reported weekly working hours used for prosthodontics and 2) reported numbers of produced single crowns, fixed partial dentures, and removable dentures. Independent variables were 'social and demographic attributes', 'job situation' and 'attitudes of dentists'. Multiple regression analysis was used in models with continuous dependent variables and logistic regression analysis for categorical dependent variables.'Weekly working hours used for dental care of adults' showed a strong association in all models with the dependent variable 'weekly working hours used for prosthodontics'. Male dentists provided more prosthodontic services than female dentists, even if reporting less time used for prosthodontics. Private practitioners produced more fixed prosthodontics than dentists employed in the public dental health service. Dentists in the public dental health service reported a higher production of removable dentures than private practitioners.The results indicate that factors, besides those in the rational clinical model for decision-making, e.g. gender and delivery system, play a role in the provision of prosthodontic services.

The purpose of this study was to describe how dentists evaluated various items related to a treatment choice between fixed partial dentures (FPD) and removable partial dentures (RPD), and to determine if the differences could be explained by dentist-related variables ("social and demographic attributes," "job situation," and "attitudes").Questionnaires were sent to a random sample of 2,059 Swedish general dentists, with a response rate of 76%. In the questionnaire, the choice between FPDs and RPDs in a clinical situation was presented. The dentists were asked to mark on 14-item visual analogue scales the relative importance he or she gave the different items. The items were analyzed through principal components analysis, where a 3-factor solution was obtained; the factors were labeled as "time," "health," and "comfort." The factors were run as dependent variables in multiple regression analyses.Great individual variations were seen, but the differences between groups of dentists were small. The items evaluated as most important were "patient's wish," "condition of possible abutment teeth," and "prognosis for delivered treatment." Male dentists gave significantly greater importance to the "health" factor compared to female dentists. The attitudinal variable "patient information" showed significant associations with all 3 factors in the multivariate models.Great individual differences were seen regarding the importance of the various items. In multiple regression models, several independent variables showed significant associations, most interestingly the attitudinal variable "patient information." Low explanatory (R2) values indicate that it is necessary to capture more variables of importance for the prosthodontic decision-making process.

The purpose of this study was to analyze dentists' evaluations of factors related to the choice between crown therapy and filling and to possibly explain this by social and demographic attributes, job situation, and dentists' attitudes.Questionnaires were sent to a random sample of 2,059 Swedish dentists. The response rate was 76%. In the questionnaire the choice between crown therapy and filling in a clinical situation was presented. The dentists were asked to mark their assessments of the relative importance of the different items on 14-item visual analogue scales (VAS). Multiple regressions were run for all 14 items.Large individual variations were seen among the dentists regarding the stated importance of the various items. The items rated as the most important were "patient's wish" and "treatment prognosis," and the items rated as least important were "treatment time required" and "number of visits required for treatment." The differences between groups were small, and for no item exceeded 0.7 step on the 8-grade VAS scale. No data reduction was possible using principal components analysis.The study showed great variations among individual dentists. The dentist-related factors explained little of the variance. The results indicated that the questionnaire instrument did not fully capture the real influences on the treatment choice between a filling and an artificial crown.

The aim of this study was to investigate attitudes among general dentists in Sweden in relation to gender, age, prosthodontic activity, and dental delivery system (private or public).Questionnaires were sent to a random sample of 2,059 dentists, and a response rate of 76% (1,567 dentists) was achieved. Among those who responded, 50% were private practitioners and 50% were publicly employed practitioners; 42% were female and 58% were male. The questionnaire contained 10 statements aimed at measuring attitudes. Their dimensionality was analyzed using principal components analysis. The resulting factors were related to delivery system (public or private), gender, age, job satisfaction, and weekly working hours used for prosthodontics in multiple regression models.There was a wide variation in the answers to the statements, indicating great individual differences in opinions among dentists. Several distributions differed with respect to gender and delivery system, but the mean differences between various groups of dentists were small. The most affirmative attitude was shown for delegation of impression taking to auxiliaries (mean 6.7; SD 1.8), and the most negative attitude was shown for close cooperation between dentists (mean 1.8; SD 1.4). The factor analysis gave 3 factors, with a variance explanation of 57%. Regression models for the 3 attitude dimensions ("patient influence," "delegation," and "patient information") showed that female dentists felt more positive about delegation and information than male dentists. The explained variance was very low for all 3 models and varied from 0.01 to 0.05.Although the differences in attitudes between various groups of dentists were statistically significant, these differences were small in relation to the large variation in attitudes among individual dentists.

The 5-year results from a multicenter study of implant-supported, laser-welded titanium frameworks are reported here as a complement to earlier reported 2-year results. Implant survival rates were satisfactory for patients with titanium frameworks and for a control group of patients with gold-alloy frameworks. At the 5-year review, more patients with titanium frameworks had lost implants than the patients with gold-alloy frameworks, but this difference was not statistically significant. More fractures of the titanium frameworks occurred, compared to the gold-alloy frameworks; again, this difference was not statistically significant. No significant differences in marginal bone levels were found between the 2 groups of patients. Slightly more fractures of artificial teeth occurred in patients with titanium frameworks than in patients with gold-alloy frameworks. Overall results for the titanium frameworks after 5 years in function are encouraging.

The aim of this study was to evaluate the clinical and radiographic performance of patients who received implants and fixed prostheses with laser-welded titanium frameworks.Fifty-eight consecutive patients were treated with 349 osseointegrated implants ad modum Brånemark in the edentulous maxilla at 6 implant centers. The patients were randomly arranged into 2 groups at the time of final impression. Twenty-eight patients received laser-welded titanium frameworks and 30 patients received conventional cast frameworks. Clinical and radiographic data were collected for 2 years in function.The 2 groups of patients showed similar results. The 2-year overall cumulative implant survival rate from the time of implant placement and prosthesis insertion was 93.7% and 96.2%, respectively. The corresponding cumulative survival rate for prostheses was 96.6%. Two patients, 1 from each group, failed completely and resumed using conventional complete dentures. The only obvious factor that could possibly be related to the 2 complete failures was a smoking habit. However, it was not possible to significantly correlate implant failures to smoking habits in this study. No fractures were observed in the frameworks or implant components, and both groups experienced the same frequency of resin veneering material fractures. The overall average marginal bone loss was 0.4 mm (SD 0.8 mm).Patients treated with implant-supported prostheses fabricated with laser-welded titanium frameworks in the edentulous maxilla presented comparable results to patients with conventional cast frameworks after 2 years in function.

The issue of changes in marginal bone levels around maxillary implants supporting overdentures has been studied very little because of radiographic difficulties when using conventional intraoral techniques. The present study used detailed narrow-beam radiography, which offers excellent opportunities to depict implants and the surrounding bone in severely resorbed maxillae. Marginal bone levels around implants in patients with overdentures were compared to corresponding bone levels in a group of matched control patients with fixed prostheses supported by osseointegrated implants. No statistically significant difference in marginal bone height was noted between the groups. This finding is not in accordance with an earlier report on continuous loss of marginal bone around many maxillary implants supporting overdentures.

Patients treated at a prosthodontic department during the years 1968-73 with fixed restorations (at least five units) were followed up in 1991-92. The aim of the present study was to compare marginal and periapical periodontal conditions on radiographs from 1968-73 and 1991-92 and relate the changes to the results of the prosthodontic treatment. In the group in which the restorations remained unchanged, 90% of the abutments that were not root filled and showed no periapical radiolucency when the restorations were placed, were still not root filled and showed no periapical radiolucency at the follow-up examination. The corresponding figure for the group in which the restorations had been replaced was only 69%. The changes in marginal bone levels also differed between the groups. In the group with remaining restorations, 66% of the surfaces were given the same score on a five-point scale both in 1968-73 and in 1991-92. In the other group, only 54% were scored the same on both occasions. Thus, unfavourable changes in both periapical and marginal periodontal conditions were associated with poorer results for the fixed restorations.

Nineteen prosthodontic clinics participated in a prospective study of fixed prostheses supported by osseointegrated implants (FPOIs) with laser-welded titanium frameworks. Ninety-three patients with 100 FPOIs were included and followed for 2 years. The results from this group were compared to another group that was examined retrospectively. In the retrospective group (control group), 91 patients received 96 FPOIs with cast frameworks, and these patients were treated shortly before the patients in the titanium-framework group (test group). The two groups were treated at the same centers. The results for both groups were good, with only 1.2% of loaded implants lost during the follow-up period (1.6% in the titanium-framework group; 0.7% in the control group). One framework in each group fractured. However, in complete maxillary cases, there were significantly more subjects in the titanium-framework group who were affected by implant losses compared to the control group. There was also a tendency towards more fractures of artificial teeth and acrylic resin in the titanium-framework group, compared to the control group. A possible explanation might be that dental technicians at the different centers were not used to the design of the titanium frameworks when the study began. Thus, the results from the first 2 years are promising, but further studies are needed to establish the long-term serviceability of laser-welded titanium frameworks.

The image quality of intraoral radiographs used by general public health dentists in prosthodontic treatment planning was evaluated on 763 radiographs from 72 consecutive cases. It was found that 349 (45.7%) radiographs were without any type error and that 414 radiographs had a total of 577 errors. The most common errors were projection and film density errors. The number of submitted radiographs ranged from 2 to 22. Three prosthodontists evaluated if the radiographs gave "satisfactory" or "not satisfactory" information for approval or not of the proposed treatment. Of the 72 cases did 34 (47%) not meet the criteria for acceptance. For the cases where the prosthodontists found the radiographic documentation "satisfactory", the mean number of periapical radiographs was 10.8, while for cases found "not satisfactory" the mean number was 7.1. This difference was found to be statistically significant (p0.01). It was shown that nearly every seventh tooth planned to be used as an abutment was radiographically not properly documented. The poor radiographic quality found in this study and in other similar studies should be taken into serious consideration, especially as prosthodontic treatment accounts for a substantial part of the total costs for dental insurance in Sweden.

At the Postgraduate Dental Education Center, Orebro, Sweden, maxillary implant-supported overdentures have mainly been used in either planned cases (where implants sufficient for a fixed prosthesis could not be placed) or emergency cases (originally planned for a fixed restoration but where implants lost during the healing period made such treatment impossible). Twenty-five cases were studied retrospectively. In the planned group, only two of 19 patients had lost an implant during the follow-up period with overdentures; in the emergency group, four subjects of six lost implant(s) during the same period. The total loss of implants during healing and overdenture function was 7% in the planned group and 72% in the emergency group. The curves for survival of overdentures without loss of supporting implants were significantly different (P = .00) for the planned group and the emergency group.

A single tooth implant was placed in a boy aged 12 years and 3 months. The case has been followed for more than 4.5 years. The fixture did not move together with the adjacent teeth as the maxillary growth went on. There was no "loss" of marginal bone on the side of one adjacent tooth where the distance between implant and tooth was appropriate. But a "loss" of marginal bone (measured from the cemento-enamel junction) was noted on the other adjacent tooth where the fixture had been placed too close to the tooth.

A questionnaire study was carried out on a random sample of 3,000 adults aged 45-69 years, living in Orebro county, Sweden. The response rate was 79.4 per cent. The purpose of this study was to develop measurements of attitudes toward dental function and dental appearance, and to investigate the relative importance of socio-economic factors to these attitudes. In factor analysis, two unidimensional variables explaining almost 54 per cent of the variance were developed, measuring the attitude to the importance of dental appearance and dental function. The variables were only moderately correlated. Bivariate and multivariate logistic regression models were constructed, where low education was related to high importance of dental appearance, and low socio-economic status and its interaction with education were related to high importance of dental function. Both models had low predictive values and no significant relationships were found with age, gender, marital status, place of residence, use of dental care, or to satisfaction with teeth or received care. It is concluded that it should be possible to influence attitudes to dental conditions irrespective of demographic or socio-economic factors.

Patients receiving artificial crowns and fixed partial dentures at a prosthodontic clinic were examined 18 to 23 years after treatment. The long-term results were good, especially for the metal ceramic restorations: 79% remained unchanged and only 3% had been removed. The success rate for the gold-resin restorations was less favorable: 43% remained unchanged and 33% had been removed. The use of one cantilever extension unit had not negatively influenced the results for the fixed partial dentures. Generally, those abutment teeth that had been removed during the observation period had received previous endodontic treatment before restorations had been placed. Endodontic complications on abutment teeth were more frequent in the mandible than in the maxillae.

The objective of the present study was to study satisfaction with previous dental care in a Swedish population aged 45-69 years. The relationship between a number of factors and satisfaction with care was studied, and differences between people attending private and public dental clinics were examined. The data were collected by an anonymous questionnaire. A multivariate analysis showed that reported satisfaction with previous dental care depended primarily on three factors; treatment by the dentist of choice, chewing ability and contentment with their own dental conditions.

For general dentists in public dental service, Orebro county, the numbers of artificial crowns, pontics, RPD:s and CRD:s produced in 1989 were studied in relation to some background factors. The dentist-related factors were: gender, time in profession, working time per week, and place of graduation. Factors related to dental clinics were: location of the clinic, general prosthodontic activity at the clinic. Multiple regression analyses were used. Two different patterns were found; one for fixed prosthodontics, another for removable prosthodontics. Prosthodontic activity at the clinic, the male sex, and (inversely) time in profession were significantly associated with high production of artificial crowns and pontics. The regression models for removable prosthodontics showed no significance.

The present paper is part of a comprehensive study of dental conditions and attitudes in a Swedish county population aged 45-69 years. A questionnaire was mailed to 3000 randomly-sampled individuals. The response rate was 79.4%. Part of the questionnaire contained questions about subjective need for implant treatment. The subjects were informed of the clinical procedures as well as of the fees for implant treatment in the Swedish insurance system. The subjects wearing removable dentures were asked if, instead of their removable denture(s), they wanted dental implants if such treatment was possible. Of those wearing removable partial dentures, 23% answered "yes". The corresponding figure for subjects totally edentulous in one jaw was 17%; for subjects totally edentulous in both jaws 8%. The individuals who had reported missing teeth not replaced were asked if they wanted their missing teeth replaced by dental implants if such treatment were possible. The % answering "yes" was 21%. The subjects with all teeth remaining were hypothetically asked what kind of treatment they wanted if they would lose 1 or 2 of their teeth. The answer "dental implant" was given by 51%. Thus, subjective need for dental implants tended to decrease with poorer dental conditions. The major reason for not wanting dental implants was satisfaction with present dental conditions. Cost for treatment had some importance, while environmental and psychological factors showed only very limited influence.

The first 50 edentulous arches treated with osseointegrated fixed partial dentures at the Postgraduate Dental Education Center, Orebro, Sweden, were studied retrospectively with concern for complications and time used for supplementary treatment and maintenance. The longest observation period was 9 years, the shortest 3 years, and the mean 5.2 years. Twenty-two percent of the patients experienced fractures of artificial teeth and/or the acrylic resin superstructure. The most severe technical complications were fractured or bent abutment screws (three) and fracture of the framework (one). The average time for supplementary treatment and maintenance was as follows: for surgery, 0.16 hours per prosthesis and year; for prosthodontics, 0.64 hours per prosthesis and year; and for dental laboratory procedures, 1.0 hour per prosthesis and year.

Eleven powders of widely different properties (various grades of WC, WO3, tungsten, iron, cobalt, SiO2, Al2O3), considered typical of the raw materials encountered in powder metallurgy, have been studied by “single value methods” (apparent and tap density, air permeametry, gas adsorption (BET)) and by “size-distribution methods” (electron- and light microscope sizing, turbidimetry, sedimentation balance (with gaseous and with liquid medium), centrifugal air classification, and sieve analysis). In addition, a series of WC powders having varying degrees of fineness has been studied by air permeametry, gas adsorption, optical reflectivity, turbidimetry, and sedimentation in air, to assess the reliable working ranges of these methods.The following topics are treated in detail: air-permeability measurements and their relation to the results of BET and other tests; electron and light-microscope sizing techniques; turbidimetry; and optical reflectivity. A microscopic study of the breakdown of agglomerate...

All 352 patients in two nursing-homes in Orebro were examined. In one of the homes microbiological tests could be done on the patients with full upper dentures. The samples were taken both from the denture and the oral mucosa. Candida albicans, Yeast, Staph. aureus, B-hemolytic streptococci and Klebsiella/Enterobacter were controlled. In samples from the oral mucosa a correlation was found between stomatitis, Candida albicans and Staph. aureus (P less than 0.01). A weak correlation was also found between stomatitis and Klebsiella/Enterobacter (0.01 less than P less than 0.05). In samples from the dentures there were only a weaker correlation between Stomatitis, Candida albicans and Staph. aureus (0.1 less than P less than 0.05).

In 1982-83 the elderly population of Orebro county, Sweden, was studied. Out of 500 randomly sampled individuals, 305 were examined clinically, 158 interviewed by telephone. Both groups were asked about i.a. the length of time since their last dental visit. In the clinical group a treatment need was assessed. Fifty percent of all reported visits to a dentist within the last three years. There were significant differences between age, residence, and especially dental status groups. The figures were slightly higher for the clinically examined group, as compared to the total: Fifty-five percent had visited a dentist within the last three years. However, the differences between the subgroups remained the same. In a multivariate analysis, two variables were significantly related to the utilization of dental services: age, and most significantly dental status. In 1986 a follow-up study was performed on the clinical group. In the years 1983-85, 69% of the subjects had received dental care. There were no differences between age, sex, or residence groups, but there were still a considerable difference between dentulous subjects (84%) and edentulous subjects (43%). The treatment received in 1983-85 was compared to the need registered in 1982-83. Only one variable - total edentulousness - was significantly related to a lower level of treatment received; whereas other variables, e.g. the income variable, were not.

The aims of the study were to survey oral health and related conditions in the population of non-institutionalized elderly people in Orebro County, Sweden, and to analyze the relative importance of certain factors within the oral health pattern. A random sample was taken of 500 non-institutionalized individuals, stratified according to age (65-74/75+) and residence (densely-populated areas/rest of county). Out of these subjects 305 were examined clinically; 158 interviewed by telephone. Totally 46% were edentulous; 35% in age group 65-74, 63% in age group 75+; 36% of the men were edentulous, 53% of the women. The lowest prevalence of edentulousness (9%) was found among married/cohabiting men in group 65-74 years, densely-populated areas. The mean number of remaining teeth in dentulous subjects was 17.1 in group 65-74 densely-populated areas; 10.1 in group 75+ rest of county. Regarding dental status the group 65-74 densely-populated areas consistently showed the best values, the group 75+ rest of county consistently showed the poorest values. Two subgroups diverged from the general pattern: the men in group 65-74 rest of county often showed poorer values than the others in aged 65-74; the men in group 75+ densely-populated areas often showed better values than the others aged 75+. The periodontal conditions were good or fairly good. Only 4% of the teeth had periodontal pockets 6 mm or deeper. Measured radiographically, about half of the teeth had 80% or more of the original bone level intact; 87% of the teeth had 60% or more of the original bone level remaining. Only 28% of the subjects had no periapical destruction. Ten percent of the teeth showed periapical destructions - 27% of root filled teeth; 6% in teeth without root fillings. Eighteen percent of the teeth were root filled - 27% of maxillary teeth, 11% of mandibular teeth. The root fillings were evaluated "not acceptable" in 69% of the teeth. Periapical destructions were more frequent in teeth with "not acceptable" root fillings as compared to those "acceptable" root filled. Socio-economic conditions were highly correlated with a number of dental parameters. In men those who were not married or cohabiting showed the poorest values; in women the differences were smaller but the highest prevalence of edentulousness was found in widows.(ABSTRACT TRUNCATED AT 400 WORDS)

An epidemiological study of oral status in two nursing-homes in Orebro was performed. Totally 352 patients were examined. In one of the nursing-home stomatitis occurred more frequent among younger than older denture wearers greater than 75 years old (P less than 0.05). In the other home there was a correlation between denture hygiene and stomatitis (P less than 0,01). The estimated need of treatment from different types of dental personal was calculated for one of the homes. 17.6% of the patients needed treatment by a dentist. For the other patients the dentist was only necessary for planning and leading treatment performed by other nursing personal.