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OBJECTIVES: The aim of the current review was to describe the prevalence of peri-implant diseases including peri-implant mucositis and peri-implantitis. MATERIAL AND METHODS: A MEDLINE search (PubMed) until December 2007 was conducted and different keywords related to the prevalence of peri-implant diseases were used. Cross-sectional and longitudinal studies including > or =50 implant-treated subjects exhibiting a function time of > or =5 years were considered. RESULTS AND CONCLUSION: The current review revealed that only a few studies provided data on the prevalence of peri-implant diseases. Cross-sectional studies on implant-treated subjects are rare and data from only two study samples were available. Peri-implant mucositis occurred in approximately 80% of the subjects and in 50% of the implants. Peri-implantitis was found in 28% and > or =56% of subjects and in 12% and 43% of implant sites. [ABSTRACT FROM AUTHOR]

BACKGROUND: The host response to microbial challenge depends on the recruitment of homing leucocytes and may be related to the experience to infectious insults over years. PURPOSE: The aim of this study was to investigate the soft tissue reactions to de novo plaque formation at sites treated with either open flap debridement or with the use of resective means during periodontal therapy. MATERIAL AND METHODS: Fifteen patients, who had been treated for periodontal disease (severe generalized chronic periodontitis), participated in the study. Surgical therapy was performed using either gingivectomy (GV) or open flap debridement (OFD) procedures in a split mouth design. After 6 months of healing (day 0), two gingival biopsies were obtained, one from the GV- and one from the OFD-treated sites. The experimental gingivitis model was applied and plaque accumulation was allowed for 3 weeks. New biopsies were obtained from the remaining quadrants on day 21 of plaque formation. The biopsies were snap frozen and prepared for immunohistochemical analysis. RESULTS: Following 3 weeks of plaque accumulation, the size of the lesion in OFD sites was more than twice as large than that in GV sites (0.42 versus 0.19 mm2). In the GV units, the lesion was characterized by almost similar proportions of T cells (CD3+, 6.0%) and B cells (CD19+, 6.6%), while the ICT in OFD sites was dominated by B cells (13.8%). During the 3-week period of plaque formation the increase in cell densities of T and B cells was three times larger in OFD than in GV sites. The proportion of ELAM-1 (CD62+ cells) decreased in GV (-0.4%) and increased in OFD (0.9%) sites. CONCLUSIONS: The host response that occurred in the gingival sites treated with OFD was more pronounced than the reaction that under similar experimental conditions took place in the regenerated gingiva at sites treated by resective means. Copyright (c) Blackwell Munksgaard, 2005. [ABSTRACT FROM AUTHOR]

Objective: The composition of universal adhesives is highly diverse. The purpose of this in vitro study was to compare the shear bond strength of a composite with five different universal adhesives to human enamel and dentin., Materials and Methods: The shear bond strength of a composite (G-aenial Universal Injectable) to human enamel and dentin was tested in selective enamel etching mode before and after thermocyclic aging (10,000 cycles) using five different universal adhesive systems (Adhese Universal VivaPen, Clearfil Universal Bond Quick, G-Premio Bond, Prime&Bond active, and Scotchbond Universal Plus). Two-bottle systems (OptiBond FL and G2-Bond Universal) were used as control. Scanning electron microscopy was conducted of the bonding interface., Results: Significant differences in shear bond strength values were found among the five evaluated universal adhesives. Lowest shear bond strength values were observed for 2-hydroxyethylmethacrylate (HEMA)-free systems. Thermocyclic aging did not significantly reduce shear bond strength values indicating that the initial bond remains stable., Conclusions: The clinical use of universal adhesives Adhese Universal VivaPen, Clearfil Universal Bond Quick, and Scotchbond Universal Plus can be encouraged as they provided comparable or even better shear bond strength values than the two-bottle controls., Clinical Significance: Universal adhesives that were developed for the same indication and approved for clinical use demonstrated variety in shear bond strength values. When applied in the selective enamel etching mode, a stable bond can be expected from adhesives containing HEMA and monomers with phosphate groups., (© 2024 The Authors. Journal of Esthetic and Restorative Dentistry published by Wiley Periodicals LLC.)

Introduction: This study analysed whether the SAZAMED (Self-assessment for dentistry studies) manual test conducted as an exercise or examination in the first year of dental studies, and the official aptitude test for medical studies (EMS), can predict future performance of dental students., Materials and Methods: Students enrolled in the dental curriculum at the University of Basel between 2009/10 and 2019/20 were categorized: Group A conducted the SAZAMED in the third bachelor year (BA) and second master year (MA), group B practiced in the first and third BA and second MA and group C had to pass the test in the first BA with repetition in the third BA and second MA. SAZAMED comprised (i) wire bending, (ii) modelling sphere and cube, (iii) drawing mirror-inverted and (iv) indirect drawing over a mirror. Comparative variables were the EMS per cent rank and test scores in practical-clinical examinations in the third BA and the second MA., Results: Data were available from 329 students over the 10-year period. Repeaters and dropouts had poorer performance in the first BA SAZAMED than students who did not (p < 0.001). Among the four SAZAMED exercises, mirror-inverted drawing was the strongest predictor of future student performance. The official aptitude test EMS correlated with the third BA certificate (p = 0.012), but failed to predict repeaters and dropouts., Conclusion: Since academic success was associated with significantly better scores on the first BA SAZAMED, it is considered a predictor and recommended in addition to the official EMS to identify students in need of intervention programmes or who should choose a different field of study., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: This article provides an overview of the implications of ChatGPT and other large language models (LLMs) for dental medicine., Overview: ChatGPT, a LLM trained on massive amounts of textual data, is adept at fulfilling various language-related tasks. Despite its impressive capabilities, ChatGPT has serious limitations, such as occasionally giving incorrect answers, producing nonsensical content, and presenting misinformation as fact. Dental practitioners, assistants, and hygienists are not likely to be significantly impacted by LLMs. However, LLMs could affect the work of administrative personnel and the provision of dental telemedicine. LLMs offer potential for clinical decision support, text summarization, efficient writing, and multilingual communication. As more people seek health information from LLMs, it is crucial to safeguard against inaccurate, outdated, and biased responses to health-related queries. LLMs pose challenges for patient data confidentiality and cybersecurity that must be tackled. In dental education, LLMs present fewer challenges than in other academic fields. LLMs can enhance academic writing fluency, but acceptable usage boundaries in science need to be established., Conclusions: While LLMs such as ChatGPT may have various useful applications in dental medicine, they come with risks of malicious use and serious limitations, including the potential for misinformation., Clinical Significance: Along with the potential benefits of using LLMs as an additional tool in dental medicine, it is crucial to carefully consider the limitations and potential risks inherent in such artificial intelligence technologies., (© 2023 The Authors. Journal of Esthetic and Restorative Dentistry published by Wiley Periodicals LLC.)

Purpose: This double-blind randomized controlled trial analyzed patient-reported outcome measures in terms of subjective patient satisfaction compared to objective dental evaluation of prosthetic treatment with 3-unit monolithic zirconium dioxide implant fixed dental prostheses (iFDPs) in 3 digital workflows., Material and Methods: Twenty patients were restored with 3 iFDPs each on Straumann TL-implants with 2 completely digital workflows using different intraoral optical scanning systems with model-free fabrication of the restoration (Trios 3/3Shape [Test-1]; Virtuo Vivo/Straumann [Test-2]), and mixed analog-digital workflow with conventional impressions and digitized gypsum casts (Impregum/3M Espe [Control]). The order of impression-taking and the prosthetic try-in were randomly allocated. Sixty iFDPs were compared for patient satisfaction and dental evaluation using ANOVA., Results: For iFDP evaluation, patients generally provided more favorable ratings than dental experts, regardless of the workflow. ANOVA revealed no significant difference for overall satisfaction when comparing Test-1, Test-2, or Control, either for patients (f-ratio: 0.13; p = 0.876) or dentist (f-ratio: 1.55: p = 0.221). Secondary, patients clearly favored the digital impression workflows over the conventional approach (f-ratio: 14.57; p < 0.001). Overall, the 3Shape workflow (Test-1) received the highest scores for all analyses., Conclusions: The different digital workflows demonstrated minor influence on the subjective and objective evaluation of the monolithic zirconium dioxide iFDPs in nonesthetic regions; however, the dentist may significantly increase patient satisfaction by choosing intraoral scanning instead of conventional impressions. The dentist has to consider individual patients' needs to fulfill their expectations for a personalized solution., (© 2022 The Authors. Journal of Prosthodontics published by Wiley Periodicals LLC on behalf of American College of Prosthodontists.)

Introduction: This prospective cohort study investigated the potential of digital assessment using intraoral scanning (IOS) combined with software analysis (prepCheck) to evaluate the outcome of repetitive tooth preparation and its influence on the acquisition of motor skills in dental students., Materials and Methods: Twenty-six students completed 177 full-crown preparations of the same tooth in six practice sessions followed by a final examination. Preparations were assessed digitally using prepCheck and conventionally by calibrated faculty instructors. In addition, students assessed their own performance and this was compared with the instructors' assessments., Results: Conventional assessment showed that students preparations improved over time, with 43.5% of students receiving score 2 (highest grade) at the fifth practice session. With the prepCheck assessment, statistically significant improvements indicated by an enlarged area within the tolerance range set at 0.2 mm were found between the first and the second practice session (7.5% improvement; 95% CI: 2.2%, 12.7%, p = 0.006), and between the first run and the final exam preparation (6.7%; 95% CI: 1.7%, 12.5%, p = 0.011). Agreement between instructor/student assessments was best immediately after students received visual feedback using prepCheck (76% agreement; Spearman's rho 0.78)., Conclusion: These data indicate that IOS technology was useful for student's self-evaluation by visual feedback., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To evaluate differences in the cellular expression of epigenetic markers and oxidative stress in periodontitis lesions between current smokers and non-smokers., Background: Tobacco smoking is recognized as one of the major risk factors for periodontitis. However, the mechanisms by which smoking affects the progression of the disease remain to be determined., Methods: Twenty-five current smokers and 21 non-smokers with generalized severe periodontitis were included. From each patient, one soft tissue biopsy from a periodontitis site was harvested and prepared for histological analysis. The infiltrated connective tissue (ICT) was selected as the region of interest to assess the cellular expression of epigenetic markers and reactive oxygen/nitrogen species (RONS) by immunohistochemistry., Results: Although the ICT of smokers and non-smokers did not differ in size or in the expression of markers for DNA damage or oxidative stress, current smokers presented with significantly lower area proportions and densities of cells positive for the epigenetic markers DNMT1 and AcH3. In addition, periodontitis lesions in current smokers presented with a diminished antimicrobial activity, as indicated by significantly lower densities and area proportions of NOX2- and iNOS-positive cells., Conclusions: Components of the host response and epigenetic mechanisms in periodontitis lesions in smokers are downregulated as opposed to lesions of non-smokers., (© 2022 The Authors. Journal of Periodontal Research published by John Wiley & Sons Ltd.)

Objective: The purpose of this study is to compare the bonding performance and mechanical properties of two different resin composite cements using simplified adhesive bonding strategies., Materials and Methods: Shear bond strength of two resin composite cements (an adhesive cement: Panavia V5 [PV5] and a self-adhesive cement: RelyX Universal [RUV]) to human enamel, dentin, and a variety of restorative materials (microfilled composite, composite, polymer-infiltrated ceramic, feldspar ceramic, lithium disilicate and zirconia) was measured. Thermocycle aging was performed with selected material combinations., Results: For both cements, the highest shear bond strength to dentin was achieved when using a primer (PV5: 18.0 ± 4.2 MPa, RUV: 18.2 ± 3.3 MPa). Additional etching of dentin reduced bond strength for RUV (12.5 ± 4.9 MPa). On enamel, PV5 achieved the highest bond strength when the primer was used (18.0 ± 3.1 MPa), while for RUV etching of enamel and priming provided best results (21.2 ± 6.6 MPa). Shear bond strength of RUV to restorative materials was superior to PV5. Bonding to resin-based materials was predominantly observed for RUV., Conclusions: While use of RUV with the selective-etch technique is slightly more labor intensive than PV5, RUV (with its universal primer) displayed a high-bonding potential to all tested restorative materials, especially to resin., Clinical Significance: For a strong adhesion to the tooth substrate, PV5 (with its tooth primer) is to be preferred because etching with phosphoric acid is not required. However, when using a wide range of varying restorative materials, RUV with its universal primer seems to be an adequate option., (© 2022 The Authors. Journal of Esthetic and Restorative Dentistry published by Wiley Periodicals LLC.)

Objective: To evaluate the efficacy of tooth splinting (TS) and occlusal adjustment (OA) compared to no TS or OA in patients with periodontitis exhibiting masticatory dysfunction., Material: The primary outcome criterion was tooth loss (TL), and the secondary outcome parameters were change in probing pocket depth (PPD), change in clinical attachment level (CAL), tooth mobility (TM), and patient-reported outcome measures (PROMs). Literature search was performed on three electronic databases (from 01/1965 to 04/2021) and focused on clinical studies with at least 12 months follow-up., Results: From a total of 1515 publications, 51 articles were identified for full-text reading, of which 2 retrospective case series on TS with low risk of bias and 1 randomized and 2 prospective studies on OA with unclear risk of bias were included. For TS, synthesis of data showed that in 72 patients, 26 out of 311 teeth (weighted mean incidence of TL 8.4%) and 156 out of 1541 teeth with no TS (weighted mean incidence of TL 10.1%) were lost over 2 years following non-surgical periodontal therapy. The randomized controlled clinical trial (RCT) indicated CAL gain for teeth with OA compared to no OA. For the effect of OA on TL, PPD, and TM, heterogeneous data were retrieved from the included studies., Conclusions: Within the limitations of this review and based on a low level of evidence, it is concluded that TS does not improve survival of mobile teeth in patients with advanced periodontitis. OA on teeth with mobility and/or premature contacts may lead to improved CAL, while the effect of OA on the remaining periodontal parameters remains unclear., (© 2021 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.)

In this cross-sectional study, the prevalences of tooth loss, prosthetic dental restorations, and probing pocket depths (PPD) ≥4 mm, and their relationship to sociodemographic factors, were investigated in older Swiss adults. There were up to 1,673 participants aged ≥55 yr in the fourth survey of the Swiss Cohort Study on Air Pollution And Lung And Heart Disease In Adults (SAPALDIA4). Missing teeth, prosthetic dental restorations, and PPD ≥4 mm were recorded in clinical examinations conducted by field workers and compared with self-reported information from questionnaires. Examination data showed that participants were missing five teeth on average, 74.8% had a prosthetic dental restoration, and 21.1% had PPD of ≥4 mm. The mean number of missing teeth and the prevalences of tooth loss, fixed dental prostheses, and removable dental prostheses were associated with age, education level, smoking status, and time since last visit to a dentist. Comparison of data obtained by field workers and that from self-reports show a high level of agreement for the number of missing teeth and the prevalence of removable dental prostheses, but a lower level of agreement for self-reports of fixed dental prostheses and periodontitis., (© 2020 Eur J Oral Sci.)

Differences in the progression of periodontitis have been observed between smokers and non-smokers. The aim of the present study was to compare vascular and inflammatory cell densities in periodontitis lesions from smokers and non-smokers to gain further understanding of the influence of smoking on histopathological characteristics of the disease. Two groups of patients with generalized severe periodontitis were recruited. One group consisted of 25 current smokers, aged 33-69 yr, while the second group comprised 21 non-smokers, aged 35-76 yr. From each patient, gingival biopsies were harvested from one periodontitis site (probing pocket depth ≥6 mm and bleeding on probing) and one site without clinical signs of gingival inflammation (reference site). Immunohistochemical analyses were performed to assess the density of vessels and inflammatory cells. Small differences existed between smokers and non-smokers regarding the size, proportion, number, and density of cells in periodontitis lesions. However, the vascular density in periodontitis lesions was significantly higher in non-smokers than in smokers. In clinically healthy reference sites, lesions were considerably smaller than in periodontitis sites and presented with similar vascular densities in smokers and non-smokers., (© 2020 Eur J Oral Sci.)

The aim of this randomized controlled trial was to analyze inexperienced dental students' perceptions of the difficulty and applicability of digital and conventional implant impressions and their preferences including performance. Fifty undergraduate dental students at a dental school in Switzerland were randomly divided into two groups (2×25). Group A first took digital impressions in a standardized phantom model and then conventional impressions, while the procedures were reversed for Group B. Participants were asked to complete a VAS questionnaire (0-100) on the level of difficulty and applicability (user/patient-friendliness) of both techniques. They were asked which technique they preferred and perceived to be more efficient. A quotient of "effective scan time per software-recorded time" (TRIOS) was calculated as an objective quality indicator for intraoral optical scanning (IOS). The majority of students perceived IOS as easier than the conventional technique. Most (72%) preferred the digital approach using IOS to take the implant impression to the conventional method (12%) or had no preference (12%). Although total work was similar for males and females, the TRIOS quotient indicated that male students tended to use their time more efficiently. In this study, dental students with no clinical experience were very capable of acquiring digital tools, indicating that digital impression techniques can be included early in the dental curriculum to help them catch up with ongoing development in computer-assisted technologies used in oral rehabilitation.

Partial ceramic crowns (PCCs) are an accepted treatment option for the restoration of posterior teeth with deficient tooth substance. Data on the survival of PCCs fabricated by dental students are scarce. The aim of this retrospective clinical study was to investigate the clinical performance and longevity of PCCs placed by dental students in the last year of their training program at the University of Basel, Switzerland. Eighty-eight patients who had received at least one PCC (n=108) in the program were considered for clinical assessment; their records were analyzed to detect previous complications or failures; and they were contacted by telephone. Criteria regarding aesthetic, functional, and biological aspects were rated with a scoring system from 1=clinically excellent to 5=clinically poor. The response rate was 66.3% (55 of 83 included patients), and 72.2% (n=78) of the PCCs were included in the analysis. Five PCCs had been lost within ten to 78 months after treatment. Six PCCs were recorded as failures (score 5), and ten received clinically unsatisfactory gradings (score 4). The risk of a clinically poor outcome was 14% after five years (86% survival), while the overall success rate was 63.5%. These results suggest that the clinical procedure of PCCs was successfully implemented by these students with satisfactory clinical survival.

Several evaluation systems for clinical exams have been suggested over the years, but no systematic analysis of checklists or criteria-based exam forms has yet been undertaken. The aims of this study were to analyze criteria-based evaluation forms and to identify areas in the teaching process potentially requiring improvements. All evaluation forms introduced in 2012 at the Clinic for Periodontology, Endodontology, and Cariology at the University Center of Dental Medicine in Basel, Switzerland, and applied over a three-year period (n=1,093 in 2015) were analyzed using predefined criteria. The authors investigated how well clinical tasks were examined with the given criteria and which criteria were preferably evaluated with a grading system (0-2) or a yes/no choice. The average final grades ranged from 0.89 (n=92) for gold inlay preparation to 1.76 (n=46) for periodontal treatment. Comments were made in 38.5% (n=356) of all exams, mainly highlighting specific aspects of existing criteria. Overall, 13 criteria out of 66 should be checked instead of graded. This methodological analysis of exam forms assessing tasks in operative dentistry yielded valuable information on areas with potential for improvement in the dental curriculum and the evaluation process. Aspects that require more theoretical background and/or hands-on recommendations from experienced clinicians were identified, and ways of further refining and redesigning the evaluation forms were proposed.

While the time trends in oral health are favourable, differences still persist in dental status and in prosthetic dental restorations (PDR) between population subgroups. This study aimed to identify changes in oral health in Switzerland over two decades and to describe their relationship to sociodemographic factors in 2012. Swiss Health Surveys were conducted in 1992, 2002, and 2012. The mean number of missing teeth and the prevalence of PDR were calculated at each time point. Logistic regression analysis was performed to assess associations between the prevalence of PDR and sociodemographic factors. The mean number of missing teeth decreased from five in 1992 to three in 2012. Dental status - as indicated by the number of teeth present - improved across all sociodemographic groups, with the greatest improvements being found in obese participants and in participants with the lowest incomes and educational levels. The prevalence of implant-based restorations increased from 3.2% in 2002 to 9.8% in 2012, and the shift from fixed to removable restorations occurred in the age group being 10 years older. The overall prevalence of PDR decreased in middle-aged people. In conclusion, over the two decades of the study, the oral health of the Swiss population substantially improved. Although sociodemographic differences persisted, they decreased considerably in terms of the number of missing teeth and percentage of the population with a functional dentition., (© 2017 Eur J Oral Sci.)

Aim: Periodontal diseases (PDs) may play an important role in the effect oral health status has on a person's quality of life (QoL). The objective was to investigate the influence of PDs (gingivitis and periodontitis) on oral health-related QoL (OHRQoL) by systematically reviewing the literature., Materials and Methods: Studies using clinical periodontal examinations and validated survey instruments were included. Among 1134 citations initially identified through electronic and hand searching, 37 were eligible and data were extracted from full texts. A vote counting method was used for synthesis of the results., Results: Included studies were published between 2001 and 2014 and revealed considerable heterogeneity in participant selection, clinical assessments, and OHRQoL measures. A significant association between PDs and OHRQoL was reported in 28 studies, of which eight reported increasing impact with greater disease severity or extent., Conclusions: Within the limits of the available literature, OHRQoL was affected by clinically assessed PDs. There was evidence for increased impairment with greater severity and extent of PDs, and the recognition of the association was increased when full mouth recording protocols were applied., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aims: Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considered as a preventive measure for the onset of peri-implantitis. Therefore, the remit of this working group was to assess the prevalence of peri-implant diseases, as well as risks for peri-implant mucositis and to evaluate measures for the management of peri-implant mucositis., Methods: Discussions were informed by four systematic reviews on the current epidemiology of peri-implant diseases, on potential risks contributing to the development of peri-implant mucositis, and on the effect of patient and of professionally administered measures to manage peri-implant mucositis. This consensus report is based on the outcomes of these systematic reviews and on the expert opinion of the participants., Results: Key findings included: (i) meta-analysis estimated a weighted mean prevalence for peri-implant mucositis of 43% (CI: 32-54%) and for peri-implantitis of 22% (CI: 14-30%); (ii) bleeding on probing is considered as key clinical measure to distinguish between peri-implant health and disease; (iii) lack of regular supportive therapy in patients with peri-implant mucositis was associated with increased risk for onset of peri-implantitis; (iv) whereas plaque accumulation has been established as aetiological factor, smoking was identified as modifiable patient-related and excess cement as local risk indicator for the development of peri-implant mucositis; (v) patient-administered mechanical plaque control (with manual or powered toothbrushes) has been shown to be an effective preventive measure; (vi) professional intervention comprising oral hygiene instructions and mechanical debridement revealed a reduction in clinical signs of inflammation; (vii) adjunctive measures (antiseptics, local and systemic antibiotics, air-abrasive devices) were not found to improve the efficacy of professionally administered plaque removal in reducing clinical signs of inflammation., Conclusions: Consensus was reached on recommendations for patients with dental implants and oral health care professionals with regard to the efficacy of measures to manage peri-implant mucositis. It was particularly emphasized that implant placement and prosthetic reconstructions need to allow proper personal cleaning, diagnosis by probing and professional plaque removal., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The articles discussed in working group 3 dealt with specific aspects of clinical research. In this context, the literature reporting on survival and complication rates of implant-supported or implant-tooth supported restorations in longitudinal studies of at least 5 years were discussed. The second aspect dealt with the evaluation of aesthetic outcomes in clinical studies and the related index systems available. Finally, the third aspect discussed dealt with patient-reported outcome measures (PROMs). A detailed appraisal of the available methodology was presented., (© 2012 John Wiley & Sons A/S.)

Aim: To compare histopathological characteristics of peri-implantitis and periodontitis lesions., Methods: A search was conducted on publications up to July 2010. Studies carried out on human biopsy material and animal experiments were considered., Results: While comprehensive information exists regarding histopathological characteristics of human periodontitis lesions, few studies evaluated peri-implantitis lesions in human biopsy material. Experimental peri-implantitis lesions were evaluated in 10 studies and three of the studies included comparisons to experimental periodontitis. Human biopsy material: the apical extension of the inflammatory cell infiltrate (ICT) was more pronounced in peri-implantitis than in periodontitis and was in most cases located apical of the pocket epithelium. Plasma cells and lymphocytes dominated among cells in both types of lesions, whereas neutrophil granulocytes and macrophages occurred in larger proportions in peri-implantitis., Experimental Studies: placement of ligatures together with plaque formation resulted in loss of supporting tissues and large ICTs around implants and teeth. Following ligature removal, a "self-limiting" process occurred in the tissues around teeth with a connective tissue capsule that separated the ICT from bone, while in peri-implant tissues the ICT extended to the bone crest., Conclusion: Despite similarities regarding clinical features and aetiology of peri-implantitis and periodontitis, critical histopathological differences exist between the two lesions., (© 2011 John Wiley & Sons A/S.)

Aim: To assess the accuracy of cone beam computed tomography (CBCT) in detecting furcation involvement (FI) in maxillary molars., Material and Methods: Fourteen patients with generalized advanced chronic periodontitis were consecutively recruited and treated non-surgically. In maxillary molars considered for furcation surgery due to increased FI and/or increased probing pocket depths during re-evaluation, CBCT was performed and the degree of FI was evaluated from the CBCT images. Furcation surgery was performed in 25 maxillary molars. Intra-surgical FI assessments were compared with data derived from CBCT images., Results: Overall, 84% of the CBCT data were confirmed by the intra-surgical findings (weighted kappa=0.926, 95% confidence interval: 0.681-1.0). While 14.7% (11 sites) were underestimated (CBCT less than intra-surgical value), in only 1.3% (one site) did the CBCT data lead to an overestimation compared with the intra-surgical analysis. The agreement between both assessments was the highest in distopalatal furcation entrances, followed by buccal and mesiopalatal., Conclusions: CBCT images demonstrate a high accuracy in assessing the loss of periodontal tissue and classifying the degree of FI in maxillary molars.

Background and Objective: Host response mechanisms in periodontal tissues are complex and involve numerous systems of interactions between cells. The B-cell lineage seems to predominate in chronic periodontitis lesions. The aim of the present investigation was to study the correlation between inflammatory cells and some functional markers in gingival lesions obtained from subjects with severe chronic periodontitis., Material and Methods: Thirty-eight Caucasian subjects volunteered to take part in the study. A gingival biopsy from one randomly selected diseased proximal site (probing pocket depth > 6 mm and bleeding on probing positive) was obtained from each patient. Immunohistochemical preparation was used to identify inflammatory cells and functional markers. Correlations between the different percentages of cell markers were analyzed by pairwise correlation., Results: B cells (B-1a and B-2 cells) occurred in larger proportions than T cells and plasma cells. A statistically significant correlation was found between the percentage of B-1a cells and plasma cells and between all B lymphocytes and plasma cells. About 60% of B lymphocytes exhibited autoreactive features., Conclusion: It is suggested that B-1a cells constitute a significant part of the host response in periodontitis lesions and that plasma cells may develop from both B-2 and B-1a cells.

Aim: To investigate the use of cone beam computed tomography (CBCT) in assessing furcation involvement (FI) and concomitant treatment decisions in maxillary molars., Material and Methods: Twelve patients with generalized chronic periodontitis were consecutively recruited and CBCT was performed in maxillary molars (n=22) with clinical FI and increased probing pocket depths. CBCT images were analysed and FI, root length supported by bone and anatomical features were evaluated. FI and treatment recommendations based on clinical examinations and periapical radiographs were compared with data derived from CBCT images., Results: The estimated degree of FI based on clinical findings was confirmed in 27% of the sites, while 29% were overestimated and 44% revealed an underestimation according to CBCT analyses. Among degree I FI, 25% were underestimated, among degree II and II-III, the underestimation was as high as 75%, while all sites with degree III FI were confirmed in the CBCT. Discrepancies between clinically and CBCT-based therapeutic treatment approaches were found in 59-82% of the teeth, depending on whether the less invasive or the most invasive treatment recommendation was selected for comparison., Conclusions: CBCT images of maxillary molars may provide detailed information of FI and a reliable basis for treatment decision.

The Swiss Health Surveys are conducted every 5 yr, and alternate surveys contain information on oral health. Worldwide the population is ageing and oral health is improving. The aim of this study was to identify if these trends are continuing in a relatively affluent society with low levels of edentulousness. Participants in the 1992 and 2002 surveys completed a written questionnaire including items on oral health (response rates 75% and 86% respectively). Data were weighted and bivariate analyses were performed to calculate the average number of missing teeth and the prevalence of different prosthetic dental restorations for each cohort. Over the 10-yr period the proportion of subjects retaining all natural teeth increased, and the mean number of teeth increased, on average, by 1.3. Among those who required prosthetic dental restorations, fixed restorations increased and complete denture use was reduced. Strikingly, 4.4% of this sample reported having oral implants in 2002. Greater numbers of missing teeth and a higher prevalence of use of removable prostheses were still seen in women, in those who had only completed compulsory education, in subjects from families with low income, in those who smoke, and in those who were overweight, in 2002.

Background: Findings from previous experiments have revealed that inflammatory cell infiltrates may remain in the gingiva following clinically successful non-surgical periodontal therapy., Purpose: To investigate the presence of inflammatory lesions in the gingiva following a periodontal treatment procedure that included either soft-tissue resection [gingivectomy (GV)] or non-resective open-flap debridement (OFD)., Material and Methods: Fifteen patients with advanced generalized chronic periodontitis were recruited. Following oral hygiene instruction and supragingival debridement, one tooth site in each quadrant (non-molar, probing pocket depth>5 mm, bleeding on probing(+) and >50% bone loss) was selected and a soft-tissue biopsy was obtained and prepared for immunohistochemical analysis. Using a split-mouth design, two quadrants were randomly selected for periodontal therapy including GV, while the two remaining quadrants were exposed to non-resective OFD procedure. Six months after completion of surgical treatment, a new set of biopsies was obtained from GV and OFD sites., Results: The inflammatory lesions residing in the gingival biopsies obtained prior to surgical therapy were 1.33-1.41 mm(2) large and contained similar proportions of CD19(+)- (B-cells, 15%), CD3(+)- (T-cells, 7%) and elastase(+)- (polymorphonuclear cells, 2%) cells in the two treatment groups. The corresponding lesions identified in the soft-tissue specimens obtained after 6 months of healing were twice as large at OFD as at GV sites (0.19 versus 0.08 mm(2), p=0.002). The densities of CD19(+)- and elastase(+)-cells in these lesions were significantly greater at OFD than at GV sites., Conclusion: The findings of the present study indicate that surgical therapy including soft-tissue resection results in regenerated gingival units that contain smaller lesions with lower densities of immunocompetent cells when compared with the lesions remaining in sites treated by non-resective means., ((c) Blackwell Munksgaard, 2005.)

Background: Periimplantitis represents an inflammatory condition that is associated with the presence of a submarginal biofilm and with advanced breakdown of soft and mineralized tissues surrounding endosseous implants. Animal models have been used to describe mechanisms involved in the pathogenesis and treatment of the soft and hard tissue lesions of periimplantitis., Objective: The aim of the present experiment was to study the presence and progression of inflammatory lesions in tissues surrounding implants exposed to "experimental periimplantitis"., Material and Methods: Five Labrador dogs were used. In each dog, 2 or 3 implants were placed in both the left and right edentulous premolar regions of the mandible. Abutment connection was performed 4 months later and a plaque control regimen was initiated and maintained for 5 months. "Experimental periimplantitis" was subsequently induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. The ligatures were removed, but plaque formation was allowed to continue for an additional 12 months. Radiographs of all implant sites were obtained before and after active "experimental periimplantitis" as well as at the end of the experiment. Biopsies were harvested from the implant sites in 3 of the dogs. The tissue samples were prepared for light microscopy and the sections were used for histometric and morphometric examinations., Results: One implant was lost during the first 2 months of "experimental periimplantitis" and two implants were lost during the 12 months that followed ligature removal. The radiographic examination indicated that varying amounts of additional bone loss occurred in the majority of the implant sites also following ligature removal. The mucosa of all implant sites harbored inflammatory lesions that extended apically of the pocket epithelium. The lesions were separated from the marginal bone by a zone of apparently normal connective tissue., Conclusion: A remission of the destructive inflammatory lesion in the periimplant tissues was seen in some sites following ligature removal, but in the majority of sites additional loss of supporting bone occurred., (Copyright Blackwell Munksgaard, 2004)

Objectives: The purpose of this study was to analyze the expression of adhesion molecules on endothelial cells in the alveolar ridge mucosa, the gingiva and the periimplant mucosa in humans., Material and Methods: Twelve partially edentulous subjects were included in the study. In each subject, one soft tissue biopsy was harvested from the edentulous alveolar ridge mucosa, one from a tooth site and one from an implant site. After 3 weeks of undisturbed plaque accumulation, an additional biopsy was obtained from one tooth and one implant site in each subject. The tissue samples were snap frozen and prepared for immunohistochemical analysis., Results: In the alveolar ridge mucosa, smaller proportions of endothelial cells expressing ICAM-1, ELAM-1 and VCAM-1 were observed than in the gingiva. ELAM-1-positive cells occurred in lower numbers than in periimplant mucosa. After 21 days of plaque accumulation, ELAM-1 was increased in tooth sites, but decreased in periimplant mucosa., Conclusion: The results of the present study indicated that the proportions of activated endothelial cells and the extravasation of leukocytes is larger in gingiva and periimplant mucosa than in alveolar ridge mucosa. This might be due to the less permeable keratinized epithelial layer in the edentulous ridge mucosa, which offers proper protection against microbial pathogens. The greater expression of endothelial cell adhesion molecules during experimental gingivitis, compared to periimplant mucositis, may reflect its longer history of repeated antigenic assaults.

Background: Findings from in vitro studies have indicated that the orientation and proliferation of cells on titanium surfaces may be influenced by the topography of the surface on which they are grown. It may be argued, therefore, that differences may occur in the mucosal attachment to titanium implants with different surface roughness., Aim: The present experiment was performed to study the composition of the soft tissue barrier that formed to implants prepared with well-defined smooth or rough surfaces., Material and Methods: Five beagle dogs were used. Four implants made of c.p. titanium were placed in the right edentulous mandibular premolar region. After 3 months, two different types of abutments were connected: one experimental (OA) with a dual, thermal acid-etched surface ('Osseotite'), and one regular (RA) abutment with a 'turned' surface. At the end of a 6-month period during which proper plaque control had been maintained, biopsies including the implant and the surrounding soft and hard tissues were obtained, decalcified and processed for light and electron microscopy. A confocal He-Ne laser profilometer was used to study the surface topography of the abutments., Results: The attachment between the peri-implant mucosa and titanium abutments with either a turned (RA; 'smooth') or acid-etched (OA; 'rough') surface was similar from both a quantitative and a qualitative aspect. The attachment comprised a barrier epithelium and a zone of connective tissue attachment of similar dimension at RA and OA. It was further observed that the 'inner' zone of the connective tissue attachment at both types of abutment was composed of about 30-33% fibroblasts and 63-66% collagen., Conclusion: It was demonstrated that the soft tissue attachment that formed to implants made of c.p. titanium was not influenced by the roughness of the titanium surface.

Background: The mucosal attachment that forms to titanium implants, uncontaminated by bacterial plaque comprises, independent of the surface characteristics of the abutment, one barrier epithelium and one zone of connective tissue attachment. It was suggested that abutments with a rough surface may accumulate more plaque than abutments with a smooth surface and that such an enhanced rate of plaque build-up may favor the development of inflammatory lesions in the periimplant mucosa., Objectives: The aim of the present experiment was to study some reactions of the periimplant mucosa to plaque accumulation on implant abutments designed with either a rough or a smooth external surface., Material and Methods: In five beagle dogs, four fixtures were placed and submerged in the premolar region. In a second stage procedure performed after 3 months, abutments with two different types of surface topography, one rough, acid-etched (OA) and one smooth, turned abutment (TA), were installed in a random order. After 6 months of undisturbed plaque formation, the animals were sacrificed and biopsies obtained. Tissue samples were prepared for light microscopy and exposed to histometric and morphometric measurements., Results: Six months of plaque accumulation resulted in the establishment of an inflammatory lesion (pl-ICT) in the connective tissue of the periimplant mucosa, the location, size and composition of which did not differ between OA and TA sites. In addition, most OA and TA sites harbored a second inflammatory cell infiltrate in the tissue lateral to the abutment/fixture junction (ab-ICT). While pl-ICT was dominated by plasma cells and lymphocytes, ab-ICT contained a comparatively large number of polymorphonuclear leukocytes., Conclusion: The different surface characteristics of abutment made of c.p. titanium failed to influence plaque formation and the establishment of inflammatory cell lesions in the periimplant mucosa.

Objectives: The purpose of this study was to examine reactions of gingiva and peri-implant mucosa (PiM) to de novo plaque accumulation in humans., Material and Methods: Prior to the start of the study, which included 12 partially edentulous subjects, a 3-week plaque control program was performed. Ethical approval was granted by the local ethics committee. On day 0, 2 soft tissue biopsies were harvested, 1 from a tooth and 1 from an implant site in every subject. After 3 weeks of undisturbed plaque accumulation (day 21), 2 additional biopsies were obtained from the gingiva and PiM in each subject. The tissue samples, each 4x4 mm in size, were snap frozen and prepared for immunohistochemical analysis., Results: The size of the infiltrate (ICT) in the day 0 biopsies, was about 0.03 mm2 in both the gingiva and PiM. At the end of the plaque accumulation period, the size of the lesion had significantly increased in both groups and occupied an area of 0.26 mm2 in the gingiva and 0.14 mm2 in PiM. In the biopsies presenting day 0, the proportions of the various cell populations examined were similar in the gingiva and in PiM. The tissue fractions of almost all types of cells increased during the 3 weeks, but the mean change for each cell type was greater in the gingiva than in PiM. The CD3/CD19 ratio decreased in the gingiva between day 0 and 21, but increased in PiM., Conclusion: The results of the present study indicated that plaque accumulation induced an inflammatory response characterized by increased proportions of T- and B-cells in the ICT of both the gingiva and the PiM. Although not statistically significant, the host response in the gingiva tended to be more pronounced than in the peri-implant mucosa.

The aim of this retrospective clinical study was to evaluate the influence of different factors on the outcome of GBR treatment. 75 patients, who were not randomly assigned to the investigated parameters for clinical reasons, were included in the study. They presented with defect sites around implants and were treated with a xenogenic grafting material and a resorbable collagen membrane. The defect morphology was described, its dimension was measured and calculated at the time of implant installation and at re-entry. The success of GBR treatment was related to several clinical variables and possible correlations were evaluated. Defect sites around maxillary implants showed significantly more bone fill (96%) compared to those in the mandible (78%). The insertion of a provisional restoration during the healing period was also associated with significantly better results than when no provisional was inserted. Immediate and short-term delayed implant placements showed the best results both with 92% bone fill, when compared with long-term delayed placements with 80% bone fill (n.s.). In sites with type I bone quality (compact bone), a reduced bone fill was observed (64%). The results indicate that successful bone fill can be achieved with GBR; this is more feasible in the maxilla, when a provisional restoration is used. Early implant placement timings seem to be preferable due to the alveolar ridge preservation, more favorable defect morphologies and a higher regenerative capacity.