Swedish dental journal. Supplement最新文献

During the last three decades there has been an increased influx of refugees and immigrants into Scandinavia. The overall aim of this thesis was primarily to improve our knowledge of malocclusion and orthodontic treatment need, both normative and self-perceived, in adolescents of varying geographic origin. A further aim was to determine whether any differences with respect to perception of general appearance and psychosocial well-being were related to geographic origin. Papers I and II concerned self perceived and normative orthodontic treatment need. About 500 12-13 year-old subjects, stratified into different groups: A-Sweden, B-Eastern/Southeastern Europe, C-Asia and D-other countries, answered a questionnaire and underwent clinical examination by the author. In paper III the association between the two variables in papers I and II was investigated. Paper IV was a follow up study, at 18-19 years of age, of the relationship between geographic origin and prevalence of malocclusion, self-perceived treatment need, temporomandibular symptoms and psychosocial wellbeing. In Paper V a qualitative study of 19-20-year-old subjects was conducted, to identify the strategies they had adopted to handle the issue of persisting poor dental aesthetics. The main findings were that at 12-13 years of age, immigrant subjects had a lower perceived orthodontic treatment need than subjects of Swedish background. Girls of Swedish background had the highest self-perceived treatment need, whilst girls of non-Swedish background were most concerned that fixed appliance therapy would be painful. In a few of the clinical variables measured at 12-13 years of age, the Swedish group exhibited the greatest space deficiency and irregularity in both the maxillary and mandibular anterior segments and greater overjet, compared to the Eastern/Southeastern European and Asian groups. The clinical implications were negligible. The orthodontic treatment need according to "Index of Orthodontic Treatment Need--Dental Health Component" (IOTN-DHC) grades 4 and 5, ranged from 30 to 40 per cent, without any inter-group differences. There were strong associations between subjects perceiving a need for orthodontic treatment and IOTN-DHC grades 4 and 5, anterior crossbite and avoiding smiling because they were self-conscious about their teeth. At the age of 18-19 years, the frequency of malocclusion was similar in all groups. Subjects of Asian origin had a higher self-perceived orthodontic treatment need than their Swedish counterparts and a higher frequency of headache than those of Eastern/Southeastern European origin. Psychological wellbeing was reduced in nearly one quarter of the sample, more frequently in girls than boys. No association was found between self-perceived orthodontic treatment need and psychological wellbeing. The theory "Being under the pressure of social norms" was generated in Paper V, and it can be applied to improve our understanding of young adults who have adjust

This thesis attempts to describe the opinion of the work with quality, quality management, and work environment among the employees at Oral and Maxillofacial Surgery (OMFS) clinics in Sweden.

This thesis aimed to: Analyse if the OMFS clinics in Sweden actively work with quality development and if so which systems they use. Explore the opinion of the employees about quality work. Describe how the employees of OMFS clinics in Sweden perceive good work, i.e., their image of the dimensions that the profession should contain to be really good work. Investigate whether there is a discrepancy between ideal and reality for this group. Describe how the employees of OMFS clinics in Sweden perceive their health. Analyse how work environment influenced attitudes to and knowledge of quality among employees of OMFS clinics in Sweden. The study was based on self-report questionnaires which in 2003 were sent to all OMFS clinics in Sweden. The response rate was 86%. Only at two clinics did all the respondents agree on their system. Surgeons rated intellectually stimulating work as most important, and the hazard-free work environment as least important. The nurses rated stimulating fellowship as most important, and the opportunity for career advancement as least important. The percentage unit differences between the ideal and the reality were largest for the item the work provides opportunities to have an influence on important decisions. There were significant differences between maxillofacial. surgeons and dental nurses and assistant nurses as to muscle- and joint trouble. The differences were also significant between men and women both as to muscle- and joint troubles and somatic trouble. Only work environment was significant for attitude towards quality work. Profession, gender, clinic size, and a factor for hard demand had significant associations to quality management system used or not.

In conclusion: More than half of the respondents stated that they worked with a quality system. The dental nurses and assistant nurses had a much more positive view on the potential of quality work as a means to improve their work than had the maxillo-facial surgeons. For a majority of the dental nurses the working situation concerning the physical environment was more important than for the maxillo-facial surgeons. The employees emphasized free, influential, and intellectually stimulating work, but the dissonance between ideal and reality was rather wide concerning good work. OMFS employees are feeling unhealthy, but no worse than other high-risk-groups in human service working and better than female general practice dentists. The women of OMFS employees feel worse than the men.

A series of studies have been initiated implying a unique opportunity to evaluate and compare malocclusion traits, orthodontic treatment need, craniofacial morphology, mandibular function, signs and symptoms of temporomandibular disorders (TMD) and headache between extremely preterm (EPT; born before the 29th week of gestation) and very preterm (VPT; born between 29 and 32 weeks of gestation) and full-term born children. THIS THESIS WAS BASED ON FOUR STUDIES: Paper I. A systematic literature review was undertaken to answer the following questions: Does prematurity result in alterations of palatal morphology, dental occlusion, tooth-crown dimensions, tooth maturation and eruption? What role does neonatal oral intubation play in the appearance of the alterations? Are the alterations in morphology permanent or transient? The literature search spanned from January 1966 to November 2002 and was later extended to September 2008. Furthermore, a quality analysis of the methodological soundness of the studies in the review was performed. Paper II-IV. The aims were to compare EPT and VPT 8- to 10-year-old children with matched full-term controls considering: Prevalence of malocclusion traits and orthodontic treatment need (Paper II). Craniofacial morphology (Paper III). Mandibular function, signs and symptoms of TMD and headache (Paper IV). KEY FINDINGS IN PAPER I AND THE SUPPLEMENTARY SEARCH: Moderate scientific evidence existed for more malocclusion traits among premature children. Limited evidence was found for no delay in dental eruption, if corrected age was considered for the premature children. Insufficientwas considered for the premature children. Insufficient evidence was found for altered tooth-crown dimensions and permanent alteration of palatal morphology among prematurely children. Thus, further well-designed controlled studies which should also consider orthodontic treatment need, craniofacial morphology, TMD and headache are needed. KEY FINDINGS IN PAPER II-IV: A higher prevalence of malocclusion traits and the assessed need of orthodontic treatment were higher among the preterm children compared with full-term born children (Paper II). Several craniofacial parameters differed significantly between preterm and full-term born children (Paper III). Preterm children did not differ from full-term born children when considering diagnoses according to the Research Diagnostic Criteria for TMD (RDC/TMD), signs and symptoms of TMD or headache (Paper IV).

Key conclusions and clinical implications: The increased survival rate of very preterm and especially the extremely preterm children contribute to a new group of children in society. The dental clinician should, therefore, be aware of the potential for a higher number of malocclusion traits, more malocclusion traits per individual, greater orthodontic treatment need and altered craniofacial morphology in prematurely born children compared with full-term born children. In

Background: Cobalt-chrome (CoCr) alloys have been used in dentistry in decades but very little is known about their behavior and biological impact as framework materials in implant dentistry. Furthermore, few studies have evaluated and compared the clinical and radiological results of abutment and abutment-free implant treatment concepts.

Aims: To investigate in vitro CoCr and commercially pure (CP) titanium frameworks regarding precision of fit, estimated material degradation and possible adverse cellular responses. In addition, to retrospectively evaluate the clinical and radiological five-year outcome of abutment-free porcelain-veneered CoCr prostheses compared to acrylic-veneered CP titanium prostheses, with or without abutments.

Materials and methods: Paper I. Two groups of cast, sectioned and laser-welded frameworks were fabricated, either in a CoCr alloy or in CP titanium. A third group comprised computer numeric controlled (CNC) milled CP titanium frameworks. Measurements of fit were performed with a coordinate measuring machine. Paper IL Ion leakage from titanium implants, CoCr and CP titanium framework sections into artificial saliva was observed with mass spectrometry. Surface structures were registered with optical interferometry. Paper III. Viability of epithelial cells and fibroblasts cultured on CoCr and titanium specimens were evaluated with the Alamar Blue method. Specimen surface structures were registered with optical interferometry and cell morphology observed with SEM. Paper IV A test group (n = 40) comprised of patients treated with prostheses made at implant level in dental-porcelain veneered CoCr alloy (n = 15) or acrylic-veneered CP titanium (n = 25). A control group (n = 40) was provided with prostheses made at abutment level, in acrylic-veneered CNC-milled CP titanium. Clinical and radiological data were evaluated after five years.

Results: Paper I. The transversal width decreased in CoCr frameworks, but increased in both groups of titanium frameworks. Less vertical distortions were present in the CNC-milled frameworks compared to the two other groups. Paper II. Significantly more cobalt ion leaked than titanium and chrome ions. Both framework sections and implants roughened after saliva exposure. Paper III. Both cell groups were more viable on titanium than on CoCr surfaces. The CoCr surfaces had a lower height deviation but were denser than the CP titanium surfaces. No major deviations from normal cell morphology were present. Paper IV. No significant differences in implant cumulative survival rates were demonstrated between the test and control groups after five years in function (98.6% and 97.6 %, respectively). No major differences in bone levels were demonstrated. Mucositis and veneer fracture were the most common complications in all groups.

Conclusions: None of the frameworks presented a perfect, compl

Radiography plays an important role in clinical routine practice and in research projects evaluating dental implants, among them Brånemark System. Presence of a peri-implant radiolucency has been used in studies as a criterion for implant failure without knowledge of its diagnostic accuracy. More precise determination, whether implants are osseointegrated or not, can be achieved if prosthetic constructions are detached to test implant stability. Such an approach is time-consuming and cumbersome. Hence, the accuracy in radiographic diagnosis of clinical instability has to be evaluated. Further, radiography is a commonly used diagnostic tool for monitoring marginal bone loss. Little is known about the observer variation. Long-term follow-up studies have shown conventional implant therapy to be a reliable procedure with few complications and minor average bone loss. Lately, studies have shown progressive bone loss in higher frequencies. When testing accuracy in diagnosis of clinical instability in intra-oral radiographs, it was found to be as good as of many other radiographic procedures, e.g. caries diagnosis. Possibility of predicting instability, however, can be low in populations with low prevalence of implants showing loss of osseointegration. Intra-observer variation was found to be the largest source of the total variation when studying inter- and intra-observer variability in radiographic bone level assessments. The number of radiographs in which individual implants were displayed had an influenced on intra-observer variation, while radiographic density and increased bone loss influenced the total inter-observer variation. Reliability can be improved by multiple readings by one observer or, even better, by letting several observers make several, independent readings, this limits the effect of a single observer who may be an outlier. Marginal bone level was assessed in 640 patients with a radiographic follow-up of > or = 5 years. The number of implants with a mean bone level of > or = 3 mm below the fixture-abutment connection increased from 2.8% at prosthesis insertion to 17.2% after 15 years. Implant-based bone loss was as a mean 0.8 mm (SD 0.8) after 5 years, followed by only minor average changes. Mean bone loss on patient level followed a similar pattern. Disregarding of follow-up time, altogether 183 implants showed a bone loss > or = 3 mm from prosthesis insertion to last examination, most of them in totally edentulous patients. Seventy of the 183 implants were found in 19 of the 107 patients. Hence, there seems to be a clustering effect. For the entire group of patients significantly larger bone loss was found the older the patient was at surgery and for lower jaw implants. Placement of the implant within the prosthetic construction, regardless of jaw-type, was found to be a predictor of a bone loss > or = 2 mm with minor bone loss around implants placed in an end position. Other predictors were age and jaw-type. The number of i

The overall aim of this thesis was to investigate different therapeutic strategies in treatment of the edentulous maxilla with dental implants and their importance for treatment outcome. The introduction of one-stage surgery, in place of two-stage surgery, was a paradigm shift in the area of implant treatment since submerged implant healing underneath the mucosa was considered a prerequisite for healing in the original concept. The advantages of a one-stage method are that a second surgery is unnecessary, costs are lower, and patients complain less about the surgical procedures. The development of implant treatment, regardless of whether it is performed in the mandible or the maxilla, strives to shorten the period from implant placement to implant loading. For the edentulous patient--due to esthetic, economical, or psychological reasons--shortening this time and thus avoiding a long period of wearing a transitional removable prosthesis is advantageous. Use of conventional one-stage surgery makes possible and is a prerequisite for immediate loading of implants. Successful treatment outcome has been demonstrated for immediate loading of implants in the mandible, but documentation of the method in the maxilla is still sparse. Two prospective clinical studies compared (i) one- and two-stage surgery and (ii) immediate and conventional loading in patients consecutively treated in the edentulous maxilla with implant-supported fixed prostheses. The first study found that the cumulative survival rate (CSR) after one-stage surgery performed according to a conventional protocol was consistent with two-stage protocol CSRs reported in previous studies. The second study evaluated an immediate loading protocol that provided patients with interim fixed prostheses within 24 hours after implant placement. A comparison of the studies found no significant difference in CSRs. But it was found that when a conventional protocol was used, transitional removable prostheses could traumatize the bone-implant interface during healing by adverse loading on the implants, which pierced the mucosa. Moreover, splinting the implants immediately after surgery with an interim fixed prosthesis might protect them from adverse loading. In a finite element analysis comparing uncoupled and splinted implants--imitations of the clinical situations in the two studies--splinted implants drastically reduced stresses in the bone tissue surrounding the implant, which might facilitate bone healing. Two factors considered important for a successful treatment outcome, especially when loading implants immediately, are (i) jawbone quality and (ii) primary implant stability at placement. In implant literature, bone quality is generally equivalent to bone density. Results of the third clinical study in this thesis indicate that use of computed tomography with calculations of bone mineral density can be a useful tool in bone tissue evaluation before implant placement. After 1 year of loading, ch

Dental caries is still a common disease among children and adolescents. The aims of the present thesis were therefore: 1) to investigate the approximal caries prevalence in posterior teeth in 15-year-olds, 2) to study past caries experience in the primary dentition in relation to future caries development and need for treatment, 3) to investigate factors during early childhood which are associated with caries development later in life, and 4) to study the association between age-specific body mass index (isoBMI) and approximal caries status in 15-year-olds. Paper I has a retrospective design and the analyses were based on record data from a randomly selected sample. Papers II, III and IV are based on radiographic analyses of posterior teeth in 15-year-olds followed longitudinally from 1 to 15 years of age. The data for these studies were selected from examinations, interviews and questionnaires from early childhood and school health care records at 15 years (isoBMI values). The result showed that the approximal caries prevalence in 15-year-olds is underestimated in official caries data, since initial caries lesions are not included in these statistics. Two thirds of all 15-year-olds had approximal caries and initial caries constituted 86% of the total number of caries lesions. There was a strong relationship between caries in early childhood and approximal caries prevalence in the posterior teeth at 15 years of age. Children with caries experience at 6 years received significantly more treatment in the primary dentition during the period from 7 to 12 years compared with children who were caries free at the same age. Further, it was pointed out that parents' attitudes to dental health and psychosocial factors during early childhood have an effect on approximal caries in 15-year-olds. Additionally, plaque on primary incisors at 1 year of age and infrequent toothbrushing at 3 years of age were associated with a high caries experience at 15 years. It was also demonstrated that adolescents with overweight and obesity had a significantly higher approximal caries prevalence than those of normal weight. Furthermore, it was shown that children's unfavourable snacking habits at 1 and 3 years of age were associated with approximal caries at 15 years. The main conclusions from this thesis are that: 1) epidemiologicalcaries data should include initial caries lesions on approximal tooth surfaces, in order to show the actual caries prevalence, 2) there is a strong relationship between caries in early childhood and approximal caries prevalence in the posterior teeth at 15 years of age, 3) the psychosocial environment in which children live during their childhood has an impact on dental health later in life, 4) good oral hygiene habits including the use of fluoride toothpaste, established in early childhood, provide a foundation for good dental health in adolescence, and 5) future preventive programmes should include, at a multidisciplinary level, strategie

National epidemiologic data on oral health in children and adolescents in Sweden are restricted to caries, such as the number of decayed and filled teeth (DFT) and decayed and filled surfaces (DFS). Information about more complicated and time-consuming procedures such as endodontic treatment is scarce. The aims were to study the prevalence, quality and potential risk factors for endodontic treatment in young permanent teeth. The material consisted of dental records and radiographs. The subjects were all 19-year-olds born in 1979 (paper I-III) and all 15-year-olds born in 1990 (paper IV) belonging to the public dental clinics in Malmo. Paper III also included a control group.

Aims: The aims of this thesis were to analyze reduced number of implants supporting full arch fixed mandibular prostheses and fixed partial dentures (FPDs), non-submerged healing and early loading in the edentulous mandible. A further aim was to evaluate fit of Computer Numerical Controlled (CNC) milled I-Bridge frameworks.

Material & methods: Paper I. One hundred and nineteen patients rehabilitated with full arch mandibular prostheses supported by four implants were evaluated after a mean follow-up of 4.4 years. Paper II. A total of 178 patients provided with FPDs supported by two (n=92) or three implants (n=122) of whom 123 were evaluated after a mean follow-up of 9.4 years. Paper III. Early and delayed loading of full arch mandibular prostheses were evaluated in 109 patients, 54 with delayed loading and 55 with early loading, with a mean follow-up of 3.6 years. Paper IV. Submerged and non-submerged implant placement for supporting fixed prostheses in the edentulous mandible were evaluated after five years in 29 patients. Paper V. The precision of fit of CNC-milled I-Bridge frameworks was evaluated using two different implant systems.

Results: Paper I. The five-year cumulative survival rate (CSR) for implants was 99.1% and for prostheses 100%. Mean bone loss from baseline to five-year follow-up was 0.5 mm. No indication could be found that the number of supporting implants influenced the prosthetic complications. Paper II. The five-year implant and prosthesis CSR was 97.7% for two-implant supported FPDs and 97.3% for three-implant supported FPDs. Mean bone loss at five years was 0.4 mm. Significantly more prosthetic and abutment screw loosening were seen in two-implant supported FPDs. Paper III. Five-year CSR for implants was 94.4% and 92.5% for prostheses in early loading, and 97.9% and 98.0% in the delayed loading group. More prostheses needed adjustment or replacement in the early group, but patients treated with early loading were more pleased with the treatment procedure. Paper IV. Five-year CSR survival rate was 99.4%. Three implants fractured in one patient. Mean bone loss at five years was 0.7 mm in submerged implants and 0.5 mm in non-submerged implants. Paper V. All frameworks demonstrated clinically acceptable fit with mean distortion values within 23 microm (x-axis), 26 microm (y), 4 microm (z- axis) and 34 microm (3-D) for all frameworks. Control frameworks displayed greater levels of distortion than frameworks produced in a strict test situation.

Conclusion: A reduction of the number of supporting implants to four implants in full arch mandibular prostheses and two implants in three unit FPDs in partial edentulous jaws resulted in the same clinical outcome as when more implants are used. Non-submerged implant placement in the edentulous mandible was as predictable as submerged, but early loading of implant-supported mandibular prostheses incur