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Objectives Dental treatments are inherently associated with the appearance of potentially infective aerosols, blood and saliva splashes. The aim of the present study was to investigate the quantitative contamination of protective eyewear during different dental treatments and the efficacy of the subsequent disinfection. Materials and methods Fifty-three standardized protective eyewear shields worn by students, dentists and dental assistants during different aerosol-producing dental treatment modalities (supragingival cleaning, subgingival periodontal instrumentation, trepanation and root canal treatment and carious cavity preparation; within all treatments, dental evacuation systems were used) were analysed, using common forensic techniques. For detection of blood contamination, luminol solution was applied onto the surface of safety shields. A special forensic test paper was used to visualize saliva contamination. Further analysis was conducted after standardized disinfection using the same techniques. Statistical analysis was performed using SPSS. Results Macroscopically detectable contamination was found on 60.4% of protective eyewear surfaces. A contamination with blood (median 330 pixels, equivalent to 0.3% of the total surface) was detected on all shields after dental treatment. Between various dental treatments, the contamination with blood tend to be statistically significant (p = 0.054). Highest amount of blood was observed after professional tooth cleaning (median 1,087 pixels). Significant differences of saliva contamination were detected between the different measurements (p Conclusions Disinfection is effective against blood and saliva contamination. Macroscopically, clean protective eyewear contains up to 12% surface contamination with blood. Based on the results, it may be concluded that protective eyewear is essential for each dental practitioner. Clinical relevance As standard for infection prevention in the dental practice, disinfection of protective eyewear after each patient is necessary.

AIM To identify dominant microorganisms in root filled teeth with apical periodontitis by Pan-PCRs in comparison with a culture-dependent approach, focusing on fungal species profiling. METHODOLOGY The root filling material (gutta-percha) removed from 42 teeth with periapical radiolucencies undergoing root canal retreatments was analysed by molecular genetics techniques. Real-Time Pan-PCRs were conducted for the diagnosis of predominant bacteria (targeting 16S rDNA) and fungi (targeting ITS1-2 region). Identification of microorganisms was performed by Sanger sequencing of the PCR products and BLAST analysis. Additionally, subgingival plaque samples were collected and cultured to review the composition of the microbial flora. The McNemar test and the repeated measures anova were used for statistical analyses (significance level was set at P

Objectives To validate a new diagnostic method (DIABRUX) for quantifying sleep bruxism (SB) activity using the current gold standard, polysomnography (PSG), as a criterion in an adequate sample size investigation. Materials and methods For SB diagnosis, each participant received a two-night ambulatory PSG including audio–video recordings. The 0.5-mm-thick sheet is produced in a thermoforming process. After diagnosis via PSG, each subject wore the diagnostic sheet for five consecutive nights. The resulting total abrasion on the surface was automatically quantified in pixels by a software specially designed for this purpose. Results Forty-five participants (10 SB and 35 non-SB subjects) were included. The difference of the mean pixel score between the SB (M = 1,306, SD = 913) and the non-SB group (M = 381, SD = 483; 3.4 times higher for SB) was statistically significant (p Conclusions The present data confirm that the new diagnostic method is valid and user-friendly that may be used for therapeutic evaluation, and for the acquisition of larger sample sizes within sophisticated study designs. Clinical relevance The verified properties of the new diagnostic method allow estimating SB activity before damages occur due to long-standing bruxism activity. Therefore, it might be utilized for preventive dentistry. Trial registration number NC T03325920 (September 22, 2017).

Background The aim of the current study was the evaluation of initial biofilm adhesion and development on laser-microtextured implant collar surfaces and the examination of effectivity of different biofilm management methods. Methods Initial biofilm formation was investigated on hydrophobic machined and laser-microtextured (Laser-Lok) titanium surfaces and hydrophobic machined and laser-microtextured (Laser-Lok) titanium aluminium vanadium surfaces and compared to hydrophobic smooth pickled titanium surfaces, hydrophilic smooth and acid etched titanium surfaces, hydrophobic sandblasted large grid and acid etched titanium surfaces (titanium Promote) via erythrosine staining and subsequent histomorphometrical analysis and scanning electron microscopic investigations. After decontamination procedures, performed via tooth brushing and glycine powder blasting, clean implant surface was detected via histomorphometrical analysis. Results After 24 h mean initial plaque area was detected in the following descending order: smooth pickled titanium > titanium Promote > hydrophilic smooth and acid etched titanium > Laser-Lok titanium > Laser-Lok titanium aluminium vanadium. The same order was determined after 48 h of biofilm formation. After glycine powder blasting all samples depicted almost 100% clean implant surface. After tooth brushing, Laser-Lok titanium (67.19%) and Laser-Lok titanium aluminium vanadium (69.80%) showed significantly more clean implant surface than the other structured surfaces, hydrophilic smooth and acid etched titanium (50.34%) and titanium Promote (33.89%). Smooth pickled titanium showed almost complete clean implant surface (98.84%) after tooth brushing. Conclusions Both Laser-Lok surfaces showed less initial biofilm formation after 24 and 48 h than the other implant surfaces. In combination with the significant higher clean implant surfaces after domestic decontamination procedure via tooth brushing, both Laser-Lok surfaces could be a candidate for modified implant and abutment designs, especially in transmucosal areas.

Background Sufficient vertical and lateral bone supply and a competent osteogenic healing process are prerequisities for the successful osseointegration of dental implants in the alveolar bone. Several techniques including autologous bone grafts and guided bone regeneration are applied to improve quality and quantity of bone at the implantation site. Depending on the amount of lacking bone one- or two-stage procedures are required. Vertical bone augmentation has proven to be a challenge particularly in terms of bone volume stability. This study focuses on the three dimensional vertical bone generation in a one stage procedure in vivo. Therefore, a collagenous disc-shaped scaffold (ICBM = Insoluble Collagenous Bone Matrix) containing rhBMP-2 (Bone Morphogenetic Protein-2) and/or VEGF (Vascular Endothelial Growth Factor) was applied around the coronal part of a dental implant during insertion. RhBMP-2 and VEGF released directly at the implantation site were assumed to induce the generation of new vertical bone around the implant. Methods One hundred eight titanium implants were inserted into the mandible and the tibia of 12 mini pigs. Four experimental groups were formed: Control group, ICBM, ICBM + BMP-2, and ICBM + BMP-2 + VEGF. After 1, 4 and 12 weeks the animals were sacrificed and bone generation was investigated histologically and histomorphometrically. Results After 12 weeks the combination of ICBM + rhBMP2 + VEGF showed significantly more bone volume density (BVD%), a higher vertical bone gain (VBG) and more vertical bone gain around the implant (PVBG) in comparison to the control group. Conclusion By using collagenous disc-shaped matrices in combination with rhBMP-2 and VEGF vertical bone can be generated in a one stage procedure without donor site morbidity. The results of the presenting study suggest that the combination of rhBMP-2 and VEGF applied locally by using a collagenous carrier improves vertical bone generation in vivo. Further research is needed to establish whether this technique is applicable in clinical routines.

The repair of skin defects in the head and neck region still poses a significant problem for many clinicians. Tissue expansion is described as a treatment option providing good color, texture, and thickness match of the expanded skin. Unfortunately, the complication rates for tissue expansion range from 0 to 48 %. Therefore, the purpose of this study was to investigate risk factors for the use of tissue expanders in head and neck reconstructions. Forty-nine patients with skin deficits in the head and neck area underwent tissue expansion. Sixty-two implanted expanders were analyzed regarding the various complications and the success rate. The success rate of treated patients was 37 (75.5 %) of all 49 included patients. The most frequent cause for the skin deficit was a tumor resection near the tip of the nose followed by skin deficits resulting after craniectomy. Interestingly, a higher number of expanders and a larger volume were significantly associated with a worse outcome. There was a trend of association between larger defect size and failure, too. The internal tissue expansion is a suitable technique for skin reconstruction in the head and face area. Compared to distant or free flaps, it often offers a better cosmetic outcome. In very large defects (>100 cm2) or when more than two expanders are needed, the failure rate increases. In these cases, other treatment options are recommended. The internal tissue expansion is a suitable technique for skin reconstruction in the head and face area.

Purpose: The present article aims to analyze the available clinical data on the survival and success rate of dental zirconia implants (ZI). Material and Method: Studies (2006–2011) listed in the bibliography were obtained by using the key words “zirconia, zirconium, implants, dental, clinical” and combinations of these in different databases and on the internet. These articles served as a basis for the article. Results: A total of 17 clinical studies were found, involving 1,675 implants and 1,274 patients. In 16 studies, one-piece implant systems were investigated. The survival rates for ZI range from 74–98% after 12–56 months, with success rates between 79.6–91.6% 6–12 months after prosthetic restoration. However, the design of most of the studies show considerable shortcomings, and only low evidence level. Conclusion: The small number of studies and the limited period of observation permit only a qualified statement on the clinical success of ZI. The results available to date indicate that ZI are inferior to titanium implants (TI) with regard to survival and success rates. Well-conducted long-term studies are urgently needed to permit a meaningful assessment of the survival or success rates of ZI and a statement concerning their application as an alternative to TI.

The purpose of this study was to investigate how patients with maxillofacial defects evaluate their quality of life after maxillectomy and prosthodontic therapy with obturator prostheses. 43 patients were included in the study (25 female, 18 male). 31 (72%) patients completed a standardized questionnaire of 143 items and then answered additional questions in a standardized interview. Global quality of life after prosthodontic therapy with obturator prostheses was 64% (±22.9) on average. Functioning of the obturator prosthesis, impairment of ingestion, speech and appearance, the extent of therapy, and the existence of pain had significant impact on the quality of life (p

Since 2008, a new polyomavirus (MCPyV) in Merkel cell carcinomas (MCC) has been described, but little is known about its impact on the clinical course. The purpose of this study was to determine the presence of MCPyV in a large sample and to correlate the results with the clinical course of the disease. 59 samples from 44 patients were analysed for the presence of MCPyV using the primers LT3, VP1 and LT1. The clinical records of these patients were evaluated and correlated with the presence of MCPyV. 58% of specimens were positive for MCPyV. Of these, LT3 was positive in 53%, VP1 in 37% and LT1 in 10%. 57% of primary tumours and 53% of metastases were positive for LT3; the numbers for VP1 and LT1 were lower. There was no correlation between the detection of MCPyV in the primary tumour and the appearance of metastases. The survival time was statistically independent from the presence of MCPyV. There is a striking occurrence of MCPyV in MCC, but whether it affects the clinical course remains unclear.

The purpose of the present investigation was to identify the most frequent therapies and, in particular, the prescription patterns for occlusal splints for the management of craniomandibular disorders (CMDs) used by German general dentists and specialists. Additionally, the knowledge and opinion of the practising dentists were examined. All active members of the statutory dental insurance providers of the German North Rhine (n = 5,500) and the Westphalia-Lippe area (n = 4,984) were surveyed with a questionnaire by mail. Results indicated that occlusal splints were the first-choice therapy followed by physiotherapy and occlusal equilibration. In the preceding year, both general dentists and specialists made 30 occlusal splints on average. With regard to high-quality evidence-based recommendations, some statistically significant discrepancies between general dentists and specialists were detected. On the basis of the present data, it seems useful to consider intensifying the topic of CMDs and orofacial pain in future undergraduate dental curricula and in postgraduate training.

Chronic osteomyelitis of the jaw is a relapsing disease with multiple treatment strategies described in the literature. Hyperbaric oxygen therapy is one of them. The purpose of this study was to evaluate the clinical outcome of hyperbaric oxygen therapy in these patients. All patients with a chronic osteomyelitis of the mandible who received in our department hyperbaric oxygen therapy between 2000 and 2004 were included in this study. The clinical outcome (lack of symptoms e.g. pain, swelling, etc.) was the pivotal evaluation parameter. All patients were divided in three groups according to their medical history. Group 1: All patients with osteomyelitis of the mandible, who received no treatment before. Group 2: All patients with one local relapse, who received only antimicrobial treatment. Group 3: Patients with at least one local relapse after antimicrobial and surgical treatment. 27 patients were evaluated in this study. Seven out of 13 patients in group 1 were relapse free after performing 40 hyperbaric oxygen therapies. However, only 4 of 9 patients in group 3 were relapse free after treatment. In group 2 the hyperbaric oxygen therapy was successful particularly in the younger patients (3 of 4). Adjuvant hyperbaric oxygen therapy was successful in the treatment of patients with chronic recurrent osteomyelitis of the mandible. Therefore, it is an treatment option which can avoid ablative surgery in some cases.

Statement of problem Occlusal load has frequently been suggested to be involved in the development of a noncarious cervical lesion (NCL). However, there is a lack of clinical studies evaluating NCLs and occlusal parameters in sleep bruxism (SB) subjects. Purpose The purpose of this clinical study was to assess the frequency of NCLs and determine potential occlusal differences between SB subjects and healthy control subjects. Material and methods A total of 91 volunteers, 58 women and 33 men, with a mean (SD) age of 28.37 (4.89) years (range of 20 to 39 years), participated in this investigation. The clinical assessment of SB was based on the criteria of the American Academy of Sleep Medicine. The participants were divided into 2 groups; 58 subjects were assigned to the SB group and 33 subjects to the control group, following a thorough dental examination that was performed by a single trained dentist. Additionally, the following parameters were recorded: mean number of teeth present, existence/absence of NCLs, frequency of NCLs relating to the type of tooth, type of occlusal guidance scheme, existence of a slide from centric occlusion (CO) to maximum intercuspation (MI), length of the slide, and report of tooth hypersensitivity. Group differences were statistically analyzed using chi-square tests for the qualitative variables and Mann-Whitney U tests for the quantitative variables (α=.05). Results NCLs were significantly more prevalent in SB subjects (39.7%) than in the control subjects (12.1%) ( P =.006). In SB subjects, the first premolars were the teeth most affected, and in control subjects, the first molars were most affected. Tooth hypersensitivity was reported in 62.1% of the SB subjects and in 36.4% of the control subjects ( P =.018). The evaluation of occlusal guidance schemes revealed no significant difference between the groups. In SB subjects (70.7%), a slide from CO to MI was significantly more prevalent than in control subjects (42.4%) ( P =.008). Moreover, SB subjects demonstrated a significantly longer mean (SD) slide of 0.77 (0.69) mm compared to that of control subjects of 0.4 (0.57) mm ( P =.008). Conclusions Within the limitations of this study, SB subjects demonstrated significantly more NCLs than the control group; whereas, the type of occlusal guidance scheme seems to be of minor importance in the development of NCLs.

Background: Despite the histopathologic findings of tumor-free margins, patients with oral squamous cell carcinoma (SCC) often suffer from local tumor relapse. The purpose of this study was to determine the prognostic value of DNA-image cytometry in the assessment of resection margins. Methods: DNA-image cytometry was performed in 40 SCC patients with histologically tumor-free resection margins. The follow-up period since the tumor resection was at least 3 years. Results: Twenty patients showed a locoregional relapse of the SCC. Fourteen of these patients had aneuploid cells in DNA-image cytometry. Two patients who were relapse-free revealed aneuploid cells too. The sensitivity of the adjuvant use of DNA-image cytometry was 70% and the positive predictive value was 87.5%. Conclusions: The additional use of DNA-image cytometry is a reasonable tool for the assessment of the resection margins of SCCs. DNA-image cytometry could help to find the appropriate treatment option for the patients and thus might improve their prognosis.

The impact of an occlusal splint (OS) compared with cognitive-behavioral treatment (CBT) on the management of sleep bruxism (SB) has been poorly investigated. The aim of this study was to evaluate the efficacy of an OS with CBT in SB patients. Following a randomized assignment, the OS group consisted of 29, and the CBT group of 28, SB patients. The CBT comprised problem-solving, progressive muscle relaxation, nocturnal biofeedback, and training of recreation and enjoyment. The treatment took place over a period of 12 wk, and the OS group received an OS over the same time period. Both groups were examined pretreatment, post-treatment, and at 6 months of follow-up for SB activity, self-assessment of SB activity and associated symptoms, psychological impairment, and individual stress-coping strategies. The analyses demonstrated a significant reduction in SB activity, self-assessment of SB activity, and psychological impairment, as well as an increase of positive stress-coping strategies in both groups. However, the effects were small and no group-specific differences were seen in any dependent variable. This is an initial attempt to compare CBT and OS in SB patients, and the data collected substantiate the need for further controlled evaluations, using a three-group randomized design with repeated measures to verify treatment effects.

Traumatisierte Patienten stellen einen bedeutenden Anteil des Behandlungsspektrums von Mund-Kiefer-Gesichts-Chirurgen, Oralchirurgen und auch Zahnarzten dar. Die Frontzahne sind dabei haufig betroffen. Konsekutive rechtliche Auseinandersetzungen werfen die Frage nach der Bedeutung von Frontzahntraumata bei Gutachten und den sich daraus ergebenden Konsequenzen fur die Erstbehandler auf. Insgesamt 398 Gutachten aus den Jahren 1999–2003 wurden retrospektiv ausgewertet. Daruber hinaus wurde eine Onlinerecherche durchgefuhrt, um Urteile mit dem Gegenstand Frontzahntrauma zu eruieren. In 97 (24,4%) Gutachten waren Verletzungen der Frontzahne Gegenstand der Fragestellung. Hauptursache fur die Verletzungen waren mit 35% Verkehrsunfalle, gefolgt von Rohheitsdelikten. Knapp ein Drittel der Gutachten wurden von Unfallversicherungen in Auftrag gegeben. Das gerichtlich zuerkannte Schmerzensgeld je Zahnverlust lag zwischen 1500 und 2000 EUR. Verletzungen der Frontzahne stellen bei Gutachten einen betrachtlichen Anteil dar und sind auch hinsichtlich Schmerzensgeldforderungen relevant. Daher ergeben sich fur den Erstbehandler hinsichtlich eines spateren Rechtsstreites hohe Anforderungen an die Befunddokumentation.

This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm (s.d., 0.69 mm) in the sleep bruxism group and a mean slide of 0.4 mm (s.d., 0.57 mm) in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects (Mann–Whitney U-test; P=0.008). However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive capacity of the stomatognathic system into future investigations.

Schwannomas, also known as neurilemomas or neurilemmomas, are relatively uncommon, slow-growing benign tumors. Whereas, about one-third of all extracranial Schwannomas are found in the head and neck region, a few intraoral Schwannomas are reported in the literature. This article contributes to a review regarding the current literature and the report of a rare case. The literature searches were performed using the National Library of Medicine. Keywords used in the search were: schwannoma or neurilemmoma and intraoral. The literature search revealed 16,906 reports containing the word schwannoma; however, only 1,117 articles described this tumor entity in the "head and neck" region. The search item intraoral, in addition to schwannoma or neurilemmoma, were found in only 29 reports. In most cases, intraoral schwannomas are benign, slowly growing tumors. The treatment of choice is surgical excision. However, malignant schwannomas can also occur, and need a radical resection and a dissection of the regional lymph nodes.

Treatment of intraoral malignant tumors often leads to continuity defects of the mandible. Whereas the use of free vascularised flaps has shortcomings regarding donor site morbidity and a worse-fitting bone geometry, the nonvascularized iliac crest graft could be an alternative option. The purpose of this study was to describe the treatment outcome with nonvascularized iliac crest grafts over a 10-year period and to determine possible limitations of their use.Eighty-four patients with bicortical nonvascularized iliac crest grafts for mandibular reconstruction were examined at least one year after reconstruction. Patients' records and the radiological and/or surgical data were analyzed.Sixty-three patients (75%) showed complete healing, in 20 patients the treatment was not successful and in one patient the treatment result was unclear. Interestingly, comparing the successfully and the unsuccessfully treated patients, only the irradiation dose played a crucial role. Neither defect length nor defect localisation, nor time interval between resection and reconstruction were statistically significant parameters in graft success. Comparing only patients with malignancies, the non-irradiated patients had a higher success rate (77.3%).The nonvaslcularized iliac crest graft seems to be a reasonably reliable treatment option for reconstruction of mandibular defects up to about 5-6 cm in size. Radiotherapy is a strong confounder reducing the success rate. Necessary constraints are sufficient soft tissue conditions. However, primary reconstruction by free flaps (e.g. fibula flap) has a higher success rate in literature and should be preferred whenever possible.

Bleeding disorders (BD) can cause significant problems during or after surgical procedures of the oral cavity. The aim of this study was to explore the risk of bleeding following oral surgery in patients with BD.The medical records of all BD patients referred to the department of cranio- and maxillofacial surgery were reviewed.Ninety-five patients (26 inherent BD, 69 taking antithrombotic drugs) were reviewed for this study. Interestingly, patients taking oral anticoagulants presented more bleeding complications than patients with inherent BD. During simple tooth extraction procedures, patients taking antithrombotic drugs had a higher risk of bleeding than patients with inherent BD.The currently available treatment protocols for surgical treatment of dental patients with inherent BD suffice. However, our data indicates that there is still a need for clear guidelines for the treatment of patients taking antithrombotic drugs, especially phenprocoumon.

Statement of problem At present, there is little information available on how practicing dentists manage bruxism patients with respect to conservative, reversible techniques as compared to irreversible techniques. Purpose The purpose of this study was to determine the most commonly applied therapies used for the management of bruxism by German general dentists (GDs) and dental specialists. In addition, efforts were made to gather information on the knowledge and opinion of GDs and specialists regarding the role of occlusal interferences, in particular, on the development of sleep bruxism. Material and methods A 13-item questionnaire was developed and mailed to all active members of the statutory dental insurance providers of the German North Rhine (n=5500; 2006 roster) and the German Westphalia-Lippe area (n=4984; 2006 roster). Group differences were statistically analyzed using chi-square tests for the qualitative variables and Mann-Whitney U tests for the quantitative variables (α=.05). Results Occlusal splints were by far the most frequently prescribed therapy for the management of bruxism, followed by relaxation techniques, occlusal equilibration, physiotherapy, and prosthodontic reconstruction. The occlusal stabilization splint with canine protected articulation was the splint type most often prescribed, whereas respondents used unadjusted soft splints for approximately 8% of their bruxism patients. Comparison of the opinions of all responding practicing dentists with that of experts in regard to the statement that "sleep bruxism is caused by occlusal interferences" showed a significant difference between the 2 groups ( P =.021). Eighty-five percent of the experts disagreed with this statement, and only 47.7% of the practicing dentists had the same opinion as the experts. Conclusions Most practicing dentists seem to concur with current scientific recommendations, and express the opinion that the management of bruxism should predominantly be conservative and reversible; however, the findings of the present survey reveal diverse differences between GDs and dental specialists concerning the most frequently prescribed therapies. Moreover, the discrepancies detected in some areas, such as the use of irreversible techniques or the use of unadjusted soft splints, emphasize the need to more promptly transfer new knowledge in the field of bruxism from researchers to practicing dentists. (J Prosthet Dent 2011;105:194-202)

Background Surgery often leads to massive destruction of the skeleton. Cell-based bone reconstruction therapies promise new therapeutic opportunities for the repair of bone. Embryonic stem cells (ESCs) can be differentiated into osteogenic cells and are a potential cell source for bone tissue engineering. The purpose of this in vivo study was to investigate the bone formation in various constructs containing ESCs (with and without micromass technology) and insoluble collagenous bone matrix (ICBM). Methods Murine ESCs were cultured as monolayer cultures as well as micromasses and seeded on ICBM. These constructs were implanted in immunodeficient rats. After one week, one, two and three months CT-scans were performed to detect any calcifications and the rats were sacrificed. Results The radiological examination shows a steep increase of the mineralized tissue in group 1 (ICBM+seeded ESC). This increase can be considered as statistical significant. In contrast, the volume of the mineralization in group 2 (ICBM+ESC-spheres) and group 3 (ESC-spheres) does not increase significantly during the study. Conclusion ESCs in combination with ICBM do promote ectopic bone formation in vivo. Thus, this cell population as well as the biomaterial ICBM might be promising components for bone tissue engineering.

The aim of this study was to evaluate the association between various functional and occlusal parameters and sleep bruxism. Thirty-nine (39) sleep bruxism patients and 30 controls participated in this investigation. The assessment of sleep bruxism was performed using the Bruxcore Bruxism-Monitoring Device (BBMD) combined with a new computer-based analyzing method. Sixteen functional and/or occlusal parameters were recorded. With a mean slide of 0.95 mm in the sleep bruxism group and a mean slide of 0.42 mm in the control group (Mann Whitney U test; p0.003), results solely demonstrated a significant group difference regarding the length of a slide from centric occlusion to maximum intercuspation. The results suggest that the slightly pronounced slide could be of clinical importance in the development of increased wear facets in patients with current sleep bruxism activity. Following further evaluation including polysomnographic recordings, the BBMD combined with this new analyzing technique seems to be a clinically feasible instrument that allows the practitioner to quantify abrasion over a short period.

Cell-based reconstruction therapies promise new therapeutic opportunities for bone regeneration. Unrestricted somatic stem cells (USSC) from cord blood and embryonic stem cells (ESCs) can be differentiated into osteogenic cells. The purpose of this in vivo study was to compare their ability to induce ectopic bone formation in vivo. Human USSCs and murine ESCs were cultured as both monolayer cultures and micromasses and seeded on insoluble collagenous bone matrix (ICBM). One week and 1, 2, and 3 months after implanting the constructs in immune-deficient rats, computed tomography scans were performed to detect any calcification. Subsequently, the implanted constructs were examined histologically. The radiological examination showed a steep increase in the mineralized bone-like tissue in the USSC groups. This increase can be considered as statistically significant compared to the basic value. Moreover, the volume and the calcium portion measured by computed tomography scans were about 10 times higher than in the ESC group. The volume of mineralization in the ESC group increased to a much smaller extent over the course of time, and the control group (ICBM without cells) showed almost no alterations during the study. The histological examinations parallel the radiological findings. Cord blood stem cells in combination with ICBM-induced ectopic bone formation in vivo are stronger than ESCs.

In dentistry, caries, pulpitis, apical periodontitis, and periodontitis represent a substantial burden for the health care system worldwide. Traditionally, clinical dental medicine is based on the removal of impaired or damaged tissues and the restoration of reduced tooth function using restorative materials. However, little of them reveal chemical, biological, or physical characteristics similar to natural enamel and/or dentine. This may result in the loss of cavity restorations [80] or may contribute to microleakage at the tooth restoration interface that will allow the infiltration of bacteria into the pulp. The barrier properties of reparative dentine were found to protect the pulp tissue better than any artificial material [131].

Background Titanium and titanium alloys are widely used for fabrication of dental implants. Since the material composition and the surface topography of a biomaterial play a fundamental role in osseointegration, various chemical and physical surface modifications have been developed to improve osseous healing. Zirconia-based implants were introduced into dental implantology as an altenative to titanium implants. Zirconia seems to be a suitable implant material because of its tooth-like colour, its mechanical properties and its biocompatibility. As the osseointegration of zirconia implants has not been extensively investigated, the aim of this study was to compare the osseous healing of zirconia implants with titanium implants which have a roughened surface but otherwise similar implant geometries. Methods Forty-eight zirconia and titanium implants were introduced into the tibia of 12 minipigs. After 1, 4 or 12 weeks, animals were sacrificed and specimens containing the implants were examined in terms of histological and ultrastructural techniques. Results Histological results showed direct bone contact on the zirconia and titanium surfaces. Bone implant contact as measured by histomorphometry was slightly better on titanium than on zirconia surfaces. However, a statistically significant difference between the two groups was not observed. Conclusion The results demonstrated that zirconia implants with modified surfaces result in an osseointegration which is comparable with that of titanium implants.

Background Osseointegration is crucial for the long-term success of dental implants and depends on the tissue reaction at the tissue-implant interface. Mechanical properties and biocompatibility make zirconia a suitable material for dental implants, although surface processings are still problematic. The aim of the present study was to compare osteoblast behavior on structured zirconia and titanium surfaces under standardized conditions. Methods The surface characteristics were determined by scanning electron microscopy (SEM). In primary bovine osteoblasts attachment kinetics, proliferation rate and synthesis of bone-associated proteins were tested on different surfaces. Results The results demonstrated that the proliferation rate of cells was significantly higher on zirconia surfaces than on titanium surfaces (p < 0.05; Student's t-test). In contrast, attachment and adhesion strength of the primary cells was significant higher on titanium surfaces (p < 0.05; U test). No significant differences were found in the synthesis of bone-specific proteins. Ultrastructural analysis revealed phenotypic features of osteoblast-like cells on both zirconia and titanium surfaces. Conclusion The study demonstrates distinct effects of the surface composition on osteoblasts in culture. Zirconia improves cell proliferation significantly during the first days of culture, but it does not improve attachment and adhesion strength. Both materials do not differ with respect to protein synthesis or ultrastructural appearance of osteoblasts. Zirconium oxide may therefore be a suitable material for dental implants.

Background Psychological factors are not only important in patients with temporomandibular disorders (TMDs), but also in patients suffering from tooth loss and/or in those awaiting prosthodontic care with fixed or removable dentures as several authors emphasize. The purpose of the present prospective observational study was to compare prosthodontic outpatients of the Department of Prosthodontics at the University of Duesseldorf and patients seeking care at the TMD/Orofacial Pain Outpatient Clinic (TMD/OFPOC) at the same university with respect to sociodemographic data, self-reported somatic complaints, and psychological impairment. Methods A total of 234 patients received two self-administered questionnaires including the Symptom-Check-List. Complete data have been obtained from 65 prosthodontic outpatients and 60 patients of the TMD/OFPOC. Results Results indicated statistically significant group differences regarding sociodemographic data and somatic complaints. Concerning the latter, in 11 of the 21 items, groups differed significantly and confirmed the absence of any mixing between the two outpatient clinics. Although the evaluation of psychological impairment revealed no significant group differences, in 21.9% of the prosthodontic outpatients and in 22.0% of the patients from the TMD/OFPOC, the extent of the determined psychological impairment was similar to that of psychotherapeutic outpatients; in 9.4% and 8.5% it was similar to that of psychotherapeutic inpatients, respectively. Conclusion Within the limitations of this study, in approximately one third of the evaluated patients of both the prosthodontic outpatient clinic and the TMD/OFPOC the psychological impairment reached values comparable to those of psychotherapeutic outpatients and psychotherapeutic inpatients. Therefore, the present findings emphasize the need to intensify the integration of psychosomatic aspects into dentistry and, in particular, to add psychological considerations to future German education plans.

Periodontal bone defects and atrophy of the jaws in an aging population are of special concern. Tissue engineering using embryonic stem cells (ESCs) and biomaterials may offer new therapeutic options. The purpose of this study is to evaluate the compatibility of ESCs with biomaterials and the influence of biomaterials on the osteogenic gene expression profile. Therefore, ESCs are cultured with various biomaterials. The cytocompatibility of murine ESCs is measured regarding the proliferation of the cells on the materials by CyQUANT ® assay, the morphology by scanning electron microscopy, and the influence on the gene expression by real time PCR. The results show that insoluble collagenous bone matrix, followed by β-tricalciumphosphate, is most suitable for bone tissue engineering regarding cell proliferation, and phenotype. The gene expression analysis indicates that biomaterials do influence the gene expression of ESCs. Our results provide new insight into the cytocompatibility of ESCs on different scaffolds.

Background: Sleep bruxism is the non-functional grinding or clenching of teeth during sleep. It may lead to tooth damage and myofascial pain. Although stress is discussed as a main causal agent, there is a lack of studies concerning coping strategies in patients with sleep bruxism. Purpose: The aim of the present study was to investigate whether bruxers, compared to non-bruxing individuals, apply maladaptive coping strategies. Method: Seventy-five sleep bruxers and 38 non-bruxers were selected by dental examination and tested by a German coping questionnaire (SVF78). Results: A significant difference in positive coping strategies was observed between the two groups. Bruxers reported less positive coping strategies, mainly less “reaction control” and “positive self-instructions.” In general, males reported less negative coping strategies. Conclusion: The reported effects demonstrate a deficit of functional coping strategies in bruxers, whereas strategies that enhance stress do not seem to be associated with sleep bruxism. Findings do not admit the conclusion that there is a causal association of maladaptive coping and bruxism. However, they support the approach of a multidisciplinary therapy involving psychological treatment.

Background Dentin dysplasia type I is characterized by a defect of dentin development with clinical normal appearance of the permanent teeth but no or only rudimentary root formation. Early loss of all teeth and concomitant underdevelopment of the jaws are challenging for successful treatment with dental implants. Methods A combination of sinus lifting and onlay bone augmentation based on treatment planning using stereolithographic templates was used in a patient with dentin dysplasia type I to rehabilitate the masticatory function. Results (i) a predisposition for an increased and accelerated bone resorption was observed in our patient, (ii) bone augmentation was successful using a mixture of allogenic graft material with autogenous bone preventing fast bone resorption, (iii) surgical planning, based on stereolithographic models and surgical templates, facilitated the accurate placement of dental implants. Conclusion Bony augmentation and elaborate treatment planning is helpful for oral rehabilitation of patients with dentin dysplasia type I.

Tissue engineering of bone and cartilage tissue for subsequent implantation is of growing interest in cranio- and maxillofacial surgery. Commonly it is performed by using cells coaxed with scaffolds. Recently, there is a controversy concerning the use of artificial scaffolds compared to the use of a natural matrix. Therefore, new approaches called micromass technology have been invented to overcome these problems by avoiding the need for scaffolds. Technically, cells are dissociated and the dispersed cells are then reaggregated into cellular spheres. The micromass technology approach enables investigators to follow tissue formation from single cell sources to organised spheres in a controlled environment. Thus, the inherent fundamentals of tissue engineering are better revealed. Additionally, as the newly formed tissue is devoid of an artificial material, it resembles more closely the in vivo situation. The purpose of this review is to provide an insight into the fundamentals and the technique of micromass cell culture used to study bone tissue engineering.

Dental floss is only used by a small part of the population on a daily basis. Therefore, an easy, applicable alternative is needed. This alternative could be a mouthrinse with antimicrobial activity for daily use. The aim of the present study was to evaluate the efficacy of two mouthrinses in reducing interdental plaque and gingivitis compared to dental floss.A total of 156 healthy volunteers were randomly assigned to the following groups: 1) toothbrushing and rinsing (0.06% chlorhexidine and 0.025% fluoride); 2) toothbrushing and rinsing (0.1% cetylpyridiniumchloride and 0.025% fluoride); 3) toothbrushing and flossing; and 4) toothbrushing only (N = 39 subjects in each group). At baseline, the modified proximal plaque index (MPPI) and papillary bleeding index (PBI) were recorded. Thereafter, subjects had to brush in the usual manner during 8 weeks. Additionally, test groups had to rinse once a day (groups 1 and 2: 30 seconds) or to floss (group 3). Eight weeks after baseline, indices were recorded again and improvements were calculated. Analysis of variance (ANOVA) and the Bonferroni test served for statistical analysis.After 8 weeks, reductions for all indices were found in all groups (P0.05). With respect to the MPPI, mouthrinse groups performed better than the control and floss groups: 1) 0.73; 2) 0.82; 3) 0.40; and 4) 0.32 (P0.05). The PBI showed no statistically significant difference between groups: 1) 0.46; 2); 0.50; 3); 0.42; and 4) 0.37.The results suggest that, in combination with toothbrushing, daily use of the tested mouthrinses may result in a higher interproximal plaque reduction than daily flossing.

To evaluate a newly developed semi-automatic computer-based method to analyze the objectivity of the Bruxcore Bruxism-Monitoring Device (BBMD) by assessing the interrater reliability. The capability of the BBMD to differentiate between sleep bruxers (SB) and healthy controls was also verified by estimating the sensitivity, specificity, and predictive values.Forty-eight SB and 21 controls took part in this investigation. After a detailed clinical dental examination, each participant received a BBMD to be worn for 5 consecutive nights. The BBMDs were then scanned and rated by 2 independent examiners using the new method, which counted the abraded area in pixels. Interrater reliability was assessed by intraclass correlation coefficient (ICC) analyses.The analyses showed a very high interrater reliability of ICC = 0.99, and comparison of the mean pixel scores revealed values that were approximately 8 times higher for the SB than for the controls. With a selected pixel score cutoff point of 2900, a sensitivity of 79.2% and a specificity of 95.2% were found. The clinical diagnosis was correctly predicted in 97.4% of the SB and 66.7% of the controls.The results support the assumption that the newly developed analyzing method for the assessment of the BBMD is a clinically suitable, objective, and applicable method that seems to be able to differentiate between SB and a healthy control sample. These data, however, need to be confirmed in further investigations using polysomnographic recordings.

Background Facial trauma or tumor surgery in the head and face area often lead to massive destruction of the facial skeleton. Cell-based bone reconstruction therapies promise to offer new therapeutic opportunities for the repair of bone damaged by disease or injury. Currently, embryonic stem cells (ESCs) are discussed to be a potential cell source for bone tissue engineering. The purpose of this study was to investigate various supplements in culture media with respect to the induction of osteogenic differentiation. Methods Murine ESCs were cultured in the presence of LIF (leukemia inhibitory factor), DAG (dexamethasone, ascorbic acid and β-glycerophosphate) or bone morphogenetic protein-2 (BMP-2). Microscopical analyses were performed using von Kossa staining, and expression of osteogenic marker genes was determined by real time PCR. Results ESCs cultured with DAG showed by far the largest deposition of calcium phosphate-containing minerals. Starting at day 9 of culture, a strong increase in collagen I mRNA expression was detected in the DAG-treated cells. In BMP-2-treated ESCs the collagen I mRNA induction was less increased. Expression of osteocalcin, a highly specific marker for osteogentic differentiation, showed a double-peaked curve in DAG-treated cells. ESCs cultured in the presence of DAG showed a strong increase in osteocalcin mRNA at day 9 followed by a second peak starting at day 17. Conclusion Supplementation of ESC cell cultures with DAG is effective in inducing osteogenic differentiation and appears to be more potent than stimulation with BMP-2 alone. Thus, DAG treatment can be recommended for generating ESC populations with osteogenic differentiation that are intended for use in bone tissue engineering.

Background Stress is discussed as a potential factor in the development of sleep bruxism (SB). The aim of this study was to investigate whether specific stress-factors correlate with SB-activity. Methods Sixty-nine subjects, of which 48 were SB-patients, completed three German questionnaires assessing different stress-parameters and stress-coping-strategies: Short questionnaire for recognition of stress-factors (Kurzer Fragebogen zur Erfassung von Belastungen, KFB), Questionnaire for recuperation and strain (Erholungs-Belastungs-Fragebogen, EBF-24 A/3) and the stress-coping questionnaire (Stressverarbeitungsfragebogen-78, SVF-78). The diagnosis of SB was based on the clinical criteria of the American Academy of Sleep Medicine (AASM). The degree of SB-activity was measured by the Bruxcore-Bruxism-Monitoring-Device (BBMD, Bruxcore, Boston, USA), worn for five consecutive nights and analyzed using a computer-based method. Non-parametric Spearman correlation coefficients, rho, were calculated between the psychometric data and the amount of SB-activity measured by a pixel score of the BBMD. Results Significant correlations were found for 'daily problems' (r = 0.461, p < 0.01), 'trouble at work' (r = 0.293), 'fatigue' (r = 0.288), 'physical problems' (r = 0.288) and the coping-strategy 'escape' (r = 0.295) (all p < 0.05). Conclusions Within the limitations of this study it could be shown that subjects with high SB-activity tend to feel more stressed at work and in their daily life, which in turn might influence their physical state. These subjects also seem to deal with stress in a negative way. However, due to the rather low to almost moderate correlation coefficients and the descriptive character of the study, further investigations are necessary to examine a possible causal relationship.