Mats Wallström

Langerin-expressing and CD83-expressing cells in oral lichen planus lesions

Objective. Dendritic Langerhans cells (LCs) have been attributed a role in the pathogenesis of lichen planus as autoantigen-presenting cells initiating expansion of autoreactive T cells. Langerin and CD83, which are cell molecules expressed on LCs, are associated with antigen presentation. The present study examined expression of Langerin and CD83 molecules on LCs in patients with oral lichen planus (OLP). Material and methods. Biopsies were obtained from seven patients with OLP. Oral mucosa from seven healthy subjects served as controls. Monoclonal antibodies (mAbs) were used in standard immunohistochemical procedures to visualize CD1a-, Langerin-, and CD83-molecule-expressing cells. Results. CD1a+ and Langerin+ cells were found in significantly higher frequencies in OLP epithelium compared with healthy oral epithelium (p<0.01 and p<0.05, respectively); however, the frequency of CD83+ cells did not differ (p>0.05). The connective tissue in OLP lesions showed significantly higher frequencies of CD1a+, Langerin+, and CD83+ cells compared with healthy connective tissue (p<0.01, p<0.01, and p<0.05). CD1a+ and Langerin+ cells in OLP and healthy epithelium had a dendritic morphology. Conclusions. The study shows increased numbers of CD1a- and Langerin-expressing LCs in OLP compared with healthy controls. In the connective tissue, CD83+ cells with dendritic morphology were localized to regions of lymphocyte clusters. The presence of CD83+ dendritic cells in areas of lymphocyte clusters in the connective tissue of OLP lesions indicates the possibility of ongoing autoantigen presentation.

Local sinus lift for single-tooth implant. I: clinical and radiographic follow-up.

BACKGROUND For single-tooth implant replacement in the posterior maxilla, it is often necessary to do an augmentation of the alveolar process because of post-extraction resorption and include part of the maxillary sinus. PURPOSE The purpose of this study is to present a technique for a local sinus lift with autogenous bone in a one-stage procedure. Additionally, volume changes of the grafted area were evaluated radiographically up to 2 years. MATERIALS AND METHODS Twenty patients, 12 female and 8 males, were included in the study. Single-tooth replacement was made in the second premolar area in 7 cases and in the molar area in 13 cases. Local sinus lift and implant installation were made simultaneously. Abutment connection was made after 6 months of healing. RESULTS Two years of clinical and radiographic follow-ups have been made in all patients. The survival rate was 100%. The residual bone volume in the actual area was 2-5 mm preoperatively, after sinus lifting in mean 13 mm, after 1 year in mean 11.4 mm, and 2 years postoperatively in mean 10.6 mm. CONCLUSIONS Local sinus lift with simultaneous bone augmentation and single-tooth replacement in the posterior maxilla is a predictable method although a certain bone volume reduction around the implant was evident at the 2-year follow-up.

Maxillary sinus augmentation with porous titanium granules: a microcomputed tomography and histologic evaluation of human biopsy specimens.

PURPOSE The aim of this study was to assess bone ingrowth into porous titanium granules used for maxillary sinus augmentation. MATERIALS AND METHODS Eighteen biopsy specimens from 17 patients participating in a clinical trial on sinus augmentation using porous titanium granules (PTG) were received in the laboratory. The specimens (trephine cores of 4.5 mm) were obtained 6 months after PTG placement. After being embedded in methacrylate, the samples were scanned in a microcomputed tomography (micro-CT) scanner. Specimens were then cut along the long axis and central slices were ground to 70 μm before staining with hematoxylin and eosin. RESULTS The micro-CT analysis demonstrated an average bone fill of 19% (standard deviation [SD] 5.8%), whereas the graft material occupied 22.7% (SD 4.7%). The volume of newly formed bone decreased with the distance from the residual bone of the sinus floor. Two-dimensional histomorphometric analysis demonstrated a mean area of new bone of 16.1% (SD 9.4%). The PTG alone occupied 25.9% of the total mean area (SD 6.1%). The newly formed bone consisted mainly of woven bone growing in close contact with the granules and bridging the intergranular space. The remaining area was occupied predominantly by nonmineralized connective tissue. There were no signs of inflammation in any of the biopsy specimens. CONCLUSIONS After 6 months, new bone had formed at a similar rate and quality as has been reported for other well-recognized bone graft substitutes. The new bone formed in close contact with the PTG, suggesting that the material is osteoconductive.

Epstein-Barr virus and human papillomavirus in snuff-induced lesions of the oral mucosa.

Epstein-Barr virus (EBV) and human papillomavirus (HPV) have been associated with benign as well as malignant oral lesions. We examined 43 patients with snuff-induced lesions and 22 control patients with clinically healthy oral mucosa for the presence of HPV and EBV. Polymerase chain reaction was performed on fresh frozen oral biopsies with degenerate consensus primers for HPV and nested primers for EBV. None of the 43 snuff-induced lesions or the 22 control biopsies were HPV-positive. Seven of the 43 (16.3%) snuff-induced lesions and one of the 22 (4.5%) controls were positive for EBV. The snuff-induced lesions were classified according to clinical severity, grade 1 lesions being the least severe and grade 4 the most severe. Eleven percent of grade 2 lesions, 15.8% of grade 3 lesions and 20% of grade 4 lesions were EBV-positive. Neither EBV nor HPV seem to be associated with snuff-induced lesions.Epstein-Barr virus (EBV) and human papillomavirus (HPV) have been associated with benign as well as malignant oral lesions. We examined 43 patients with snuff-induced lesions and 22 control patients with clinically healthy oral mucosa for the presence of HPV and EBV. Polymerase chain reaction was performed on fresh frozen oral biopsies with degenerate consensus primers for HPV and nested primers for EBV. None of the 43 snuff-induced lesions or the 22 control biopsies were HPV-positive. Seven of the 43 (16.3%) snuff-induced lesions and one of the 22 (4.5%) controls were positive for EBV. The snuff-induced lesions were classified according to clinical severity, grade 1 lesions being the least severe and grade 4 the most severe. Eleven percent of grade 2 lesions, 15.8% of grade 3 lesions and 20% of grade 4 lesions were EBV-positive. Neither EBV nor HPV seem to be associated with snuff-induced lesions.

Titanium Granules for Augmentation of the Maxillary Sinus – A Multicenter Study

BACKGROUND Biomaterials are commonly used to augment the maxillary sinus floor prior to or in conjunction with dental implant installation. Recently, porous titanium granules (PTGs) have been used in oral implant surgery to stabilize implants and function as an osteoconductive matrix. PURPOSE To evaluate if PTGs can be safely used in a larger population of patients, treated by different surgeons, when sinus floor augmentation was required in conjunction with implant installation. The primary endpoint was 12-month survival rate of the dental implants. Biopsies for histology were taken from the augmented area. MATERIALS AND METHODS At five centers, 40 subjects with uni or bilateral posterior edentulism and atrophy of the posterior maxilla (3-6 mm) were enrolled. In a single-stage procedure, PTG and one to three dental implants were installed in each quadrant. In total, 70 implants were included in the study. RESULTS One immobile implant was removed. The mean marginal bone loss was 0.5 mm and 0.8 mm, on the mesial and distal side, respectively. Histologically, all biopsies demonstrated bone ingrowth. CONCLUSIONS The results suggest that PTG can be safely and effectively used as augmentation material in the sinus floor when used with dental implants in a one-stage procedure.

A cessation program for snuff-dippers with long-term, extensive exposure to Swedish moist snuff : A 1-year follow-up study

Abstract Objective. Smokeless tobacco (Swedish moist ‘snus’) users are often strongly addicted to nicotine. Compared to the large number of smoking-cessation studies, there have been few evaluated clinical cessation programs in conjunction with nicotine replacement therapy (NRT). The aim of this study was to evaluate a cessation program for snus users with a weekly use of >2 cans/week for >10 years. Material and methods. A prospective, open, non-randomized intervention trial was undertaken including baseline oral examination and soft tissue biopsy, minor physical examination, brief cessation advice, NRT recommendations and five prospective follow-up visits within 12 months. Individual cessation counseling was given, together with oral examination in the dental office. Fifty snus users with a minimum consumption of 100 g/week who were actively seeking cessation treatment were recruited through advertising. Self-reported abstaining, including random-sample biochemical verification, and NRT use were evaluated at 6 weeks and 3, 6 and 12 months. Results. At the 3-, 6- and 12-month visits, 58%, 46% and 30% of subjects, respectively were tobacco-abstinent. All nicotine abstinence was randomly controlled during the study except at 12 months, where all subjects claiming abstinence were confirmed biochemically and clinically. Conclusion. Smokeless tobacco cessation achieved together with suitable NRT seems a promising way to improve a persistent tobacco-free condition.

Potentially Malignant Oral Disorders and Cancer Transformation

Cancer in the oral cavity is often preceded by precursor lesions. Nine oral mucosal disorders are known to have an increased risk of malignant transformation. The etiology varies from disorders caused by exogenous factors such as tobacco and autoimmune inflammation to idiopathic or inherited genetic aberrations. In this review, these potentially malignant disorders (PMDs) are described regarding clinical presentation and histopathological architecture. Special attention is paid to the underlying etiologies of PMDs and the potential pathways leading to cancer. The clinical perspective focuses on the importance of accurate and timely diagnosis.