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Redfors Y.D.,Institute of Clinical science | Grondahl H.G.,Institute for Postgraduate Dental Education | Grondahl H.G.,Gothenburg University | Hellgren J.,Institute of Clinical science | And 4 more authors.
Otology and Neurotology | Year: 2012

Objective: To assess the use of cone beam computed tomography (CBCT) compared with multi-slice computed tomography (MSCT) in otosclerosis, with special emphasis on middle- and inner-ear anatomy. Study Design: Prospective study. Patients: Twenty patients who underwent a stapedectomy 30 years ago were selected on the basis of bone conduction threshold values. Their mean age was 65 years (range, 48-76 yr). Intervention: All patients underwent CBCT and MSCT with a slice thickness of 0.5 to 0.6 mm. Main Outcome Measures: Sixteen middle- and inner-ear anatomic structures and stapedial prostheses were analyzed by visual grading analysis. To assess critical reproduction and thereby the clinical applicability of CBCT, a dichotomization was made. Assessment of otosclerotic foci was performed using a grading system dividing the lesions in; 1) sole fenestral lesions, 2) retrofenestral lesions with or without fenestral lesions and 3) severe retrofenestral lesions. Results: The 16 anatomic structures were clearly reproduced by both imaging techniques. However, there was an interobserver variation in judging the superiority of 1 method in favor of the other. Otosclerotic lesions were diagnosed in 80/95% using MSCT and 50/85% using CBCT (evaluators 1 and 2, respectively). Retrofenestral lesions were diagnosed in 5 of 10 of ears with severe-to-profound hearing loss, whereas no retrofenestral lesions were diagnosed in the 10 ears with mild-to-moderate hearing loss. The stapedial prostheses were adequately or very well reproduced by both methods. Conclusion: CBCT is a new imaging technique with a considerably lower radiation dose than conventional MSCT. Our study indicates that CBCT is suitable and, in many ways, equivalent to MSCT, for temporal bone imaging in otosclerosis. © 2012, Otology & Neurotology, Inc.


Lofthag-Hansen S.,Gothenburg University | Lofthag-Hansen S.,Public Dental Health | Thilander-Klang A.,Gothenburg University | Thilander-Klang A.,Sahlgrenska University Hospital | And 2 more authors.
European Journal of Radiology | Year: 2011

Aims: To evaluate subjective image quality for two diagnostic tasks, periapical diagnosis and implant planning, for cone beam computed tomography (CBCT) using different exposure parameters and fields of view (FOVs). Materials and methods: Examinations were performed in posterior part of the jaws on a skull phantom with 3D Accuitomo (FOV 3 cm × 4 cm) and 3D Accuitomo FPD (FOVs 4 cm × 4 cm and 6 cm × 6 cm). All combinations of 60, 65, 70, 75, 80 kV and 2, 4, 6, 8, 10 mA with a rotation of 180° and 360° were used. Dose-area product (DAP) value was determined for each combination. The images were presented, displaying the object in axial, cross-sectional and sagittal views, without scanning data in a random order for each FOV and jaw. Seven observers assessed image quality on a six-point rating scale. Results: Intra-observer agreement was good (κ w = 0.76) and inter-observer agreement moderate (κ w = 0.52). Stepwise logistic regression showed kV, mA and diagnostic task to be the most important variables. Periapical diagnosis, regardless jaw, required higher exposure parameters compared to implant planning. Implant planning in the lower jaw required higher exposure parameters compared to upper jaw. Overall ranking of FOVs gave 4 cm × 4 cm, 6 cm × 6 cm followed by 3 cm × 4 cm. Conclusions: This study has shown that exposure parameters should be adjusted according to diagnostic task. For this particular CBCT brand a rotation of 180° gave good subjective image quality, hence a substantial dose reduction can be achieved without loss of diagnostic information. © 2010 Elsevier Ireland Ltd.


Magnusson A.,Institute for Postgraduate Dental Education | Bjerklin K.,Institute for Postgraduate Dental Education | Kim H.,Harvard University | Nilsson P.,Institute for Postgraduate Dental Education | Marcusson A.,Linköping University
American Journal of Orthodontics and Dentofacial Orthopedics | Year: 2013

Introduction: The aim of this prospective, longitudinal study was to evaluate changes to the external shape and form of the nose after surgically assisted rapid maxillary expansion and orthodontic treatment. The changes were registered using a 3-dimensional computer tomography technique, based on superimposition on the anterior base of the skull. Methods: The subjects comprised 35 patients (mean age, 19.7 years; range, 16.1-43.9 years). Low-dose, helical computerized tomography images were taken at treatment start and after orthodontic treatment, about 18 months postsurgery. The 3-dimensional models were registered and superimposed on the anterior cranial base. Results: There were in general significant widening and overall anterior and inferior displacement of the nasal soft tissues. The changes varied in size and direction. No correlation was found between the initial and final widths of the nose, or between the initial and final widths of the nostrils. Conclusions: After surgically assisted rapid maxillary expansion, the most obvious changes to the external features of the nose were at the most lateral alar bases. The difference in lateral displacement profoundly influenced the perception of a more rounded nose. Patients with narrow and constrained nostrils can benefit from these changes. The 3-dimensional superimposition applied in this study is a reliable method, circumventing projection and measurement errors. Copyright © 2013 by the American Association of Orthodontists.


Stensson M.,Health Science University | Koch G.,Institute for Postgraduate Dental Education | Coric S.,Institute for Postgraduate Dental Education | Abrahamsson T.R.,Linköping University | And 3 more authors.
Caries Research | Year: 2014

The aim of this study was to evaluate the effect on oral health, at age 9 years, of daily oral supplementation with the probiotic Lactobacillus reuteri, strain ATCC 55730, to mothers during the last month of gestation and to children through the first year of life. The study was a single-blind, placebo-controlled, multicenter trial involving 113 children: 60 in the probiotic and 53 in the placebo group. The subjects underwent clinical and radiographic examination of the primary dentition and carious lesions, plaque and gingivitis were recorded. Saliva and plaque were sampled for determination of mutans streptococci (MS) and lactobacilli (LB) in saliva and plaque as well as salivary secretory IgA (SIgA). Forty-nine (82%) children in the probiotic group and 31 (58%) in the placebo group were caries-free (p < 0.01). The prevalence of approximal caries lesions was lower in the probiotic group (0.67 ± 1.61 vs. 1.53 ± 2.64; p < 0.05) and there were fewer sites with gingivitis compared to the placebo group (p < 0.05). There were no significant differences between the groups with respect to frequency of toothbrushing, plaque and dietary habits, but to intake of fluoride supplements (p < 0.05). There were no intergroup differences with respect to L. reuteri, MS, LB or SIgA in saliva. Within the limitation of this study it seems that daily supplementation with L. reuteri from birth and during the first year of life is associated with reduced caries prevalence and gingivitis score in the primary dentition at 9 years of age. © 2013 S. Karger AG, Basel.


Thorstensson H.,Institute for Postgraduate Dental Education | Thorstensson H.,National University of Health Sciences | Johansson B.,University Institute of Health Sciences | Johansson B.,Gothenburg University
Gerodontology | Year: 2010

Objectives: To analyse the importance of caries, periodontitis, and medical and psychosocial factors for risk of becoming edentulous across their lifespan and to examine factors critical for retaining functional dentition into very old age. Methods: From the longitudinal population-based Octogenarian Twin study which analysed psychosocial and health variables, 357 individuals aged 82 + in 1995-1998 were collected. Information about number of teeth, decayed and filled surfaces percentage and periodontal disease experience were drawn from dental records. Reasons for and time of edentulousness were recorded. Results: Outcome varied - depending on perspective and factors for losing or retaining teeth. Significant factors for losing teeth varied over the lifespan. Losing teeth early in life was related to lower social class; in middle age, to lower education; and in old age, to poor lifestyle factors and low social class. Caries constituted the main reason for tooth loss (about 55%). This increased substantially in the >80 year age-group (75%). Maintaining a functional dentition into old age was significantly associated with non-smoking, more education, being married and good periodontal health. Conclusion: It is important to apply life-span and cohort perspectives to oral health and disease. In our sample of persons born before World War I, caries was the main reason for losing all teeth, with substantially increased prevalence by age. Lifestyle factors were significant for losing and for retaining teeth. Periodontal condition had a significant influence on the likelihood of retaining functional dentition, and also when taking psychosocial variables into account. © 2009 The Gerodontology Society and John Wiley & Sons A/S.


Alm A.,Karnsjukhuset | Wendt L.K.,Health Science University | Koch G.,Institute for Postgraduate Dental Education | Birkhed D.,Gothenburg University | Nilsson M.,Futurum the Academy of Healthcare
Community Dentistry and Oral Epidemiology | Year: 2012

Objective: To analyse the relationship between caries determinants in early childhood and caries prevalence in proximal surfaces in adolescents at the age of 15 years. Methods: The present longitudinal study is part of a series of surveys of oral health in 671 children followed from 1 to 15 years of age. Data were selected from examinations, interviews and questionnaires at 1, 3 and 6 years and bitewing radiographs at 15 years of age. Uni- and multivariable logistic regression analyses were performed to identify caries-related determinants. The outcome variable was carious lesions and fillings (DFa) in approximal tooth surfaces at 15 years of age. Statistical comparisons were made between caries-free teenagers, DFa = 0 and teenagers with DFa > 0, DFa ≥ 4 and DFa ≥ 8, respectively. Results: In the final logistic regression analyses, caries experience at 6 years and mother's self-estimation of her oral health care as being less good to poor remained statistically significant and were related to caries in all three caries groups (i.e. DF > 0, ≥4 and ≥8) at 15 years of age. The consumption of sweets at 1 year remained statistically significant, with a caries experience of DF ≥ 4 and ≥ 8. The variables 'parents born abroad' and female gender were statistically significantly associated with DFa ≥ 4 and DFa ≥ 8, respectively. Furthermore, infrequent toothbrushing habits at 3 years of age and failure to attend the examination at 1 year were statistically significantly associated with caries at 15 years in the univariable analyses. Conclusion: Early caries experience, consumption of sweets at an early age and mother's self-estimation of her oral health care as being less good to poor are associated with approximal caries in adolescents. The study indicates that caries determinants identified during early childhood have a strong impact on approximal caries in adolescence. © 2011 John Wiley & Sons A/S.


Johansson V.,Malmö University | Axtelius B.,Malmö University | Soderfeldt B.,Malmö University | Sampogna F.,Malmö University | And 3 more authors.
Community Dentistry and Oral Epidemiology | Year: 2010

Objectives: Since 1999, the public dental health service (PDHS) in the county of Värmland, Sweden, has two co-existing patient financial systems, i.e. ways for the patient to pay for dental care services. Alongside the traditional system of fee-for-service payment, i.e. paying afterwards for provided services, a new system of contract care is offered. In this system, dental care is covered by a contractual agreement, for which the patient pays an annual fee and receives care covered by the contract without additional costs. The aim of this article was to study whether patient financial system was associated with oral health-related quality of life (OHRQoL). Methods: A questionnaire was answered by 1324 randomly selected patients, 52% from contract care and 48% from fee-for-service. The questionnaire contained questions about how much one was prepared to pay for dental care, how much one paid for dental care the previous year, OHIP-14 (measured OHRQoL), dental anxiety, humanism of caregiver, SF-36 (measured general health), multidimensional health locus of control, sense of coherence (SOC), self-esteem and demographics. Data on patient financial system, gender and age were obtained from the sampling frame. The material was analysed with a hierarchical block method of multiple regression analysis. Results: When controlling for all other variables, patient financial system was one of the strongest associations with OHRQoL: patients in fee-for-service had worse OHRQoL than those in contract care. OHRQoL was also associated with general health, SOC and to some extent also with psychological and economic factors. Of the social variables, only being foreign born was significant: it was associated with worse OHRQoL. Conclusions: Patient financial system was associated with OHRQoL when controlling for confounding factors: patients in contract care had better OHRQoL than those in fee-for-service care. © 2010 John Wiley & Sons A/S.


Slotte C.,Institute for Postgraduate Dental Education | Lindfors N.,Institute for Postgraduate Dental Education | Lindfors N.,Gothenburg University | Nannmark U.,Gothenburg University
Clinical Implant Dentistry and Related Research | Year: 2013

Background: Surgical reconstruction of peri-implant defects is challenging and unpredictable due to, for example, the extent of the bone defect or the osteogenic potential of adjunctive materials used. Purpose: To study the healing capacity of a new bone xenograft material in the treatment of peri-implant defects. Material and Methods: In three cases with advanced peri-implant defects, flap surgery was performed. After thorough debridement including cleaning of the exposed implant surface, prehydrated and collagenated porcine bone (PCPB) particles were placed into the defect. A bioresorbable collagen barrier was adapted and placed over the defect and the flaps were relocated. After 6 and 12 months of healing, clinical and radiographic examinations were done. In one case, the surgical procedure was repeated 6 months postoperatively. One year after the second surgery, a bone biopsy was harvested and analyzed with histology. Results: All defects healed uneventfully. At 6 months, probing depths were reduced by 3-4mm with no bleeding on probing or pus formation. At 12 months, healthy peri-implant conditions were found. Intra-oral radiographs showed gain of the marginal bone level by 2-4mm. In the case where reconstructive surgery was repeated, histology showed osteoconductive properties as bone formation with typical osteoblastic seams was observed directly on the surface of the grafted particles. Conclusion: The presented cases show that PCPB have favorable properties enhancing bone regeneration in peri-implant bone defects. © 2011 Wiley Periodicals, Inc.


Berden J.,Institute for Postgraduate Dental Education
European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry | Year: 2010

AIM: To present a series of clinical cases of children treated for large dentigerous cysts with a conservative and tissue preserving surgical approach. METHODS: A follow-up study of 11 children aged 5-11 years old treated for large dentigerous cysts with decompression. The children were followed from the first appointment when the cysts were diagnosed until the full eruption of the involved and displaced teeth. The treatment procedure is described step by step. Three of the 11 cases are presented in detail. RESULTS: All permanent teeth displaced by the dentigerous cysts, except a wisdom tooth and a maxillary canine, erupted in a correct position and in good occlusion. No facial disfigurations or defects of oral tissues occurred. CONCLUSIONS: A decompression approach, as described in this paper, is rewarding for the patient and the surgeon. It would be unethical and destructive to the maxillofacial bone structure not to treat large dentigerous cysts in children by decompression.


Magnusson C.,Public Dental Health | Nilsson M.,Academy for Health and Care | Magnusson T.,11 Health | Magnusson T.,Institute for Postgraduate Dental Education
Acta Odontologica Scandinavica | Year: 2010

Objective. Controversy exists concerning the etiological factors behind degenerative changes in the temporomandibular joints (TMJs). Tooth attrition, occlusal support, food consistency, ageing, gender and genetics are some possible causative factors that have been discussed in the literature. The aim of this study was to examine contemporary human skull material for possible relations between degenerative form and surface changes in the TMJs in relation to occlusal support. Material and methods. The material consisted of 259 human skulls from 170 males and 89 females, with an age range of 18100 years. Results. Dental status was in general poor, and 22% of skulls were edentulous. Form and surface changes of both the condyles and the temporal components were more common in the present material compared to that in most previous studies. In males, irrespective of age, only weak and clinically insignificant correlations could be found between degenerative TMJ changes and occlusal support. In women, however, the correlations between these variables were in general much stronger, especially at higher ages. Conclusions. The present findings do not lend support to the hypothesis that loss of occlusal support is a causative factor for degenerative changes in the TMJs in male subjects. In women, such a correlation was obvious in the present sample, at least at higher ages. It can be speculated that hormonal factors play a role in the sex difference found. © 2010 Informa UK Ltd.

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