Prognose und Prognosefaktoren enossaler Implantate im bestrahlten Kiefer

Zusammenfassung Einleitung: Die kaufunktionelle Wiederherstellung nach Kopf-Hals-Bestrahlung ist gegenuber anderen Tumorpatienten durch Strahlenkaries, Radioxerostomie und Osteoradionekroserisiko zusatzlich limitiert. Es wurde der Frage der Implantatprognose und potentieller Prognosefaktoren im bestrahlten Kiefer nachgegangen. Material und Methode: Die retrospektive Studie erfaste von 1988–1997 197 Implantate (47 Patienten). Die Implantatprognose wurde durch Uberlebenszeitanalyse (Kaplan-Meier) bestimmt, wobei implantatunabhangige Verluste zensiert wurden. Auserdem erfolgte eine Gruppenbildung nach potentiell die Prognose beeinflussenden Parametern. Grupppenunterschiede in den Uberlebensrat…

Retained pieces of wood in the retromaxillary space: a case report.

Detection and operative removal of wood as a foreign body in the cranio-maxillary area has received frequent attention in the literature. However, as a rule, most of the cases described are related to the orbit or the orbito-neurocranial space. Almost no literature exists on the detection and treatment of wooden foreign bodies in the retromaxillary space. The authors present an unusual case of long-term retained wood in this area in a child. The case inspires discussion of the general problem of detecting retained retromaxillary wood, even using modern diagnostic tools in this area and the question of the operative therapy, especially the most favourable surgical access.

EGFR and PCNA experession in oral squamous cell carcinomas—a valuable tool in estimating the patient's prognosis

We investigated 100 cases of oral squamous cell carcinomas immunohistologically with respect to the expression of the epidermal growth factor receptor (EGFR) and the proliferating cell nuclear antigen (PCNA). The results were correlated with a new malignancy grading of the invasive tumour areas and the clinical outcome of the patients to estimate the individual prognosis. In conclusion, the amount of antigen expression of both antigens increases with the increasing grade of malignancy of the oral squamous cell carcinoma. Furthermore, there is a statistically significant correlation between the amount of antigen expression and the patient's prognosis. An overexpression of EGFR and PCNA is as…

Expression of cytokeratin 17 mRNA in oral squamous cell carcinoma cells obtained by brush biopsy: preliminary results.

Background:  The aim of this study was to determine the detection of cytokeratin (CK) mRNA in oral squamous cell carcinoma (OSCC) cells and to evaluate the CK relevance for OSCC diagnosis in a brush biopsy test. Methods:  Fifty-two pairs of OSCC cells and normal oral mucosal cells were obtained by brush biopsy from OSCC patients. mRNA was extracted from cell pellets for real-time quantitative reverse transcriptase polymerase chain reaction (RT-qPCR). The over-expression levels of CK 17, CK 19 and CK 20 mRNA in OSCC cells were examined by SYBR green real-time RT-qPCR. Results:  Compared to normal mucosal cells, the over-expression of CK 17 mRNA was detectable in 40 OSCC cells (76.9%), that o…

Immediate and flapless implant insertion and provisionalization using autogenous bone grafts in the esthetic zone: 5-year results.

Objectives As the 2-year results for immediately inserted and provisionalized implants have been reported, it remained an open issue, whether the initially high success rates and the esthetic outcome remain stable for longer observation periods. Therefore, this prospective study examines the 5-year hard and soft tissue changes at implants placed in the anterior maxilla. Material and methods Meanwhile, 37 microthreaded implants were placed in 21 patients into extraction sockets with and without facial bone deficiencies by a flapless approach. Facial gaps and bony defects were grafted with autogenous bone chips. The implants were immediately provisionalized. The primary outcome parameters wer…

Modification of xenogenic bone substitute materials - effects on the early healing cascadein vitro

Introduction Initial platelet activation with subsequent cytokine release at the defect site plays a crucial role in tissue integration. The aim of this study was to evaluate the influence of topographic and biomimetic collagen modifications of a xenogenic bone substitute material (BSM) on in vitro platelet activation and cytokine release. Material and Methods Three types of xenogenic BSM were used. Two BSM with different levels of granularity (large granule BSM [XBSM/L], small granule BSM [XBSM/S]) and a BSM with collagen (XBSM/C). All three samples were incubated with platelet concentrate of four healthy volunteers at room temperature for 15 min. For all groups, highly thrombogenic collag…

A modified surgical approach for hard and soft tissue reconstruction of severe periimplantitis defects – Laser‐assisted periimplant defect regeneration (LAPIDER)

Clinical and radiographic performance of self‐locking conical connection implants in the posterior mandible: Five‐year results of a two‐centre prospective study

Abstract Objective This prospective study aims to assess the 5‐year clinical performance of implants with internal conical connection and platform‐switched abutments in the posterior mandible. Material and Methods Healthy adults missing at least two teeth in the posterior mandible and with a natural tooth mesial to the implant site received two or three adjacent implants. After a transmucosal healing period single crown restorations were cemented on platform‐switched abutments. Changes in marginal bone levels were investigated in standardized periapical radiographs from surgery and loading (baseline) to 60‐months post‐loading. Results Twenty‐four patients received 52 implants. Bone remodell…

Konfokale Laser-Scanning-Mikroskopie (CLSM): Histotomographie veränderter Zahnhartgewebe bei pathologischer Mundhöhlenökologie

There is no consensus regarding the aetiology of radiation-induced caries. Lesion formation is assumed to originate either from direct radiogenic damage of the hard tissue or from the indirect effects correlated with radioxerostomia. A comparative study is presented of sound teeth (group 1), teeth with documented radiation caries (group 2), teeth after in situ radiation (group 3): 60 Gy, fractionated) and teeth after in vitro radiation (group 4: 500-2500 Gy). Radiations were carried out with a 60Co source. The dentoenamel junction was studied with confocal laser scanning microscopy (CLSM). Axial sections of the teeth were used either fresh or embedded in Technovit (sawing-grinding technique…

Acoustic Airway Profiles in Unilateral Cleft Palate Patients

Objective: This study investigates the nasal airway in unilateral cleft palate patients by means of a noninvasive, objective diagnostic method that provides topographic information about the airway profile. Design: A consecutive sample of patients was measured. Setting: Cleft palate rehabilitation center of the University of Mainz, Germany. Patients: Forty-nine subjects were investigated: 34 full-grown patients with complete unilateral cleft lip and palate and 15 controls with subjective normal nasal patency. Intervention: A transnasal series of three acoustic measurements of nasal volume was performed per nostril; measurements were taken both before and after decongestion with 0.3 mg xylom…

Vertical Bone Augmentation with Simultaneous Dental Implantation Using Crestal Biomaterial Rings: A Rabbit Animal Study

Background: Ceramic biomaterial blocks like hydroxyl apatite are too brittle for simple simultaneous vertical augmentation and dental implant placement. Biological scaffolds of xenogenic or allogenic origin are known to be advantageous. Purpose: The aim of this study was the proof of principle for combined vertical bone augmentation and dental implantation with marginal cuffs made of biological scaffolds with interconnecting porous system and titanium dental implants. Materials and Methods: Cylindrical porcine biomaterial rings (processed, mineralized bone matrix) were placed in combination with titanium dental implants in the tibia model using six chinchilla bastard rabbits (n = 12 samples…

Dexrazoxane shows cytoprotective effects in zoledronic acid-treated human cells in vitro and in the rabbit tibia model in vivo

Abstract Introduction Bisphosphonates are important and effective drugs in oncology and osteoporosis therapy. They accumulate in the bone matrix becoming released and active by bone resorption. This leads to effective inhibition of tumor cells and bone degradation. A side effect of bisphosphonates similar to other drugs like denosumab is osteonecrosis of the jaws (ONJ). This problem mostly occurs after tooth extraction. We studied the cytoprotectant dexrazoxane known from anthracycline chemotherapy for cytoprotection in nitrogen-containing bisphosphonate treated cells and in the rabbit tibia model to evaluate a possible value in ONJ management. Materials & methods Human osteoblasts (HOB) P2…

Survival and tissue maintenance of an implant with a sloped configurated shoulder in the posterior mandible-a prospective multicenter study.

Aim Clinical studies evaluating the influence of the implant design on the preservation of peri-implant keratinized mucosa are rare. The aim of this prospective multicenter study was to investigate the survival, and soft and hard tissue maintenance of an implant with a sloped shoulder configuration, when placed in the posterior mandible. Material and Methods In this study, 24 centers participated and 184 patients receiving 238 implants (OsseoSpeed™ Profile TX implants) were included. Clinical assessments of soft tissue parameters were performed before implant placement, immediately after implant placement, at prosthetic delivery and at 6, 12 and 24 months after implant placement and margina…

Terminal end of the human odontoblast processes

Die Rosai-Dorfman-Lymphadenopathie, eine seltene reaktive lymphoproliferative Erkrankung

Aim The established criteria for benignity or malignancy of lymph nodes when evaluated with B-mode ultrasound can be divided into quantitative measures (size, quantity, contour and density) and qualitative parameters (configuration and structure). The validity of these criteria is controversial. Methods Two cases of sinus histiocytosis with massive lymphadenopathy (SHML) are presented; this is a rare benign reactive disorder in which massive enlargement of cervical lymph nodes often occurs. These enlarged nodes offer a chance to demonstrate and discuss the validity of the sonomorphological criteria. Results The enlarged lymph nodes in SHML fulfill most of the criteria for malignancy. The sa…

Platform switch versus platform match in the posterior mandible – 1-year results of a multicentre randomized clinical trial.

Objective The purpose of this ongoing randomized study was to assess differences in bone level changes and success rates using implants supporting single crowns in the posterior mandible either with platform matched or platform switched abutments. Material and Methods Patients aged 18 and above, missing at least two teeth in the posterior mandible and with a natural tooth mesial to the most proximal implant site were enrolled. Randomization followed implant placement. Definitive restorations were placed after a minimum transgingival healing period of 8 weeks. Changes in crestal bone level from surgery and loading (baseline) to 12-month post-loading were radiographically measured. Implant su…

Immediate provisionalization of Astra Tech implants in healed and extraction sites: 1 to 11‐year results

Objective, Noninvasive Evaluation of Velopharyngeal Function in Cleft and Noncleft Patients

Objective The purpose of this study was to investigate a new diagnostic method that provides an approach to noninvasive, objective measurement of velopharyngeal movement by acoustic determination of epipharyngeal volume changes with velopharyngeal muscle function. Design This was a case control study, using consecutive samples. Setting This study took place at the Cleft Palate Rehabilitation Center of the University of Mainz, Germany. Patients Subjects were 29 consecutive cleft lip and palate (CLP) patients and 31 controls (21 patients with dysgnathia and 10 healthy volunteers). Intervention A series of transnasal acoustic measurements (pressure wave: 55 dB for 2 milliseconds) of epipharyng…

Osseointegration of one-piece zirconia implants compared with a titanium implant of identical design: a histomorphometric study in the dog

Objective: The aim of this study was to evaluate osseointegration of one-piece zirconia vs. titanium implants depending on their insertion depth by histomorphometry. Material and methods: Four one-piece implants of identical geometry were inserted on each side of six mongrel dogs: (1) an uncoated zirconia implant, (2) a zirconia implant coated with a calcium-liberating titanium oxide coating, (3) a titanium implant and (4) an experimental implant made of a synthetic material (polyetheretherketone). In a split-mouth manner they were inserted in submerged and non-submerged gingival healing modes. After 4 months, dissected blocks were stained with toluidine blue in order to histologically asse…

Maintenance of marginal bone support and soft tissue esthetics at immediately provisionalized OsseoSpeed implants placed into extraction sites: 2-year results.

Background Placement of implants into extraction sockets targets the maintenance of peri-implant hard and soft tissue structures and the support of a natural and esthetic contour. The main advantages of immediate implant insertion in comparison with delayed implant placement protocols are as follows: a reduced treatment time, less number of sessions, and, thus, the less invasive procedure. This study examines the clinical performance (survival rate, marginal bone levels and Pink Esthetic Score [PES]) of OsseoSpeed™ implants placed into extraction sockets with immediate provisionalization in the anterior maxilla after a follow-up of at least 12 months. Methods Twenty patients received a tota…

Radiation response non-invasively imaged by [18F]FDG-PET predicts local tumor control and survival in advanced oral squamous cell carcinoma

It is a major challenge to preoperatively identify patients who will profit from surgery of advanced oral cancer. In multimodality therapy, response to neoadjuvant radiation correlates to treatment success. Hence, for preoperative decisions, assessment of treatment response is required. Therefore, we analysed the prognostic significance of glucose metabolism after preoperative radiotherapy. [(18)F]FDG-PET investigations were performed for re-staging 35 patients after neoadjuvant radiotherapy (36Gy) immediately prior to tumor resection. Emission and transmission measurements were obtained and SUV's were calculated for the sites of maximum [(18)F]FDG-uptake. Subpopulations of "low" (SUV4) and…

Immediate Nonfunctional Loading of NobelPerfect Implants in the Anterior Dental Arch in Private Practice - 5-Year Data

Background: The concept of scalloped implants to maintain the natural contour of the alveolar ridge has been a source of controversy for many years. Purpose: This study examined the long-term clinical performance of the scalloped NobelPerfect implant in a one-stage procedure (immediate loading in the esthetic zone). Materials and Methods: In 20 patients, immediate prosthetic restorations were placed on 31 NobelPerfect implants in a private practice and followed for up to 78 months. Twenty-one implants were placed immediately after extraction, seven implants were placed after osseous consolidation of the extraction sockets, and three implants were placed secondary to extended alveolar ridge …

Histotomography of the odontoblast processes at the dentine-enamel junction of permanent healthy human teeth in the confocal laser scanning microscope

The translucency of teeth allows the non-destructive subsurface visualisation of their microstructure by confocal laser scanning microscopy (CLSM) at a level of about 150 μm below the surface. The dentine–enamel junction (DEJ) is accessible only directly adjacent to the cervix of the tooth. Therefore teeth have to be sectioned for studying marginal areas of the dental hard tissue. The potential of the technique for (pseudo) three-dimensional visualisation allows the study of an array of individual confocal images, the interpretation of which is similar to that of macroscopic tomographs (CT-scan, MRI). Additionally, the extended focus mode yields the overlay of individual confocal images in …

Psammous desmo-osteoblastoma

Fibro-osteo-cemental lesions of the jaw bones are a heterogeneous group of diseases which present problems in classification. Psammous desmo-osteoblastoma is one of four newly proposed entities (Makek 1983) and has until now been characterized by its light microscopic, clinical and radiological features. On electron microscopy this tumour exhibits fibroblastic (preosteoblastic), osteoblastic and osteocytic cells and a globular mineralization unlike the mineralization of the psammoma bodies. Immunohistological investigations with anti-osteonectin, a bone specific protein linking mineral to collagen, showed positive intracellular staining in all tumour cells and extracellular staining in the …

Nasal airway in cleft-palate patients: acoustic rhinometric data

The objective of this study was to investigate an instrumental assessment technique for acquiring reproducible, metric data on the nasal airway in cleft-palate associated nasal dysplasia. A consecutive sample of 23 unilateral, 17 bilateral CLP patients and 15 controls with subjective normal nasal patency from a cleft-palate rehabilitation centre were studied. A series of transnasal acoustic measurements (pressure wave: 55 dB for 2 ms) of nasal volume were performed before and after topical decongestion with 2 x 0.3 mg of xylometazoline. A standardized regimen of acoustic parameters of the nasal valve and the adjacent segment of the nasal cavity were calculated. The cleft side yielded a sign…

Primary Stability of a Hybrid Self-Tapping Implant Compared to a Cylindrical Non-Self-Tapping Implant with Respect to Drilling Protocols in an Ex Vivo Model

Background: Modifications of implant design have been intending to improve primary stability. However, little is known about investigation of a hybrid self-tapping implant on primary stability. Purposes: The aims of this study were to evaluate the primary stability of two hybrid self-tapping implants compared to one cylindrical non-self-tapping implant, and to elucidate the relevance of drilling protocols on primary stability in an ex vivo model. Materials and Methods: Two types of hybrid self-tapping implants (Straumann® Bone Level implant [BL], Straumann® Tapered Effect implant [TE]) and one type of cylindrical non-self-tapping implant (Straumann® Standard Plus implant [SP]) were investig…

Prophylaxis of radiogenic sialadenitis and mucositis by coumarin/troxerutine in patients with head and neck cancer--a prospective,randomized, placebo-controlled, double-blind study.

To study the efficacy of coumarin/troxerutine for the protection of salivary glands and mucosa during irradiation. Design: Prospective, randomized, placebo-controlled, double-blind trial. Setting: University hospital, Germany. Patients: 48 patients who had radiotherapy to the head and neck. Main outcome measures: Salivary gland scintigraphy and acute side-effects of radiotherapy (Radiation Therapy Oncology Group (RTOG) score). Results: 23 patients (11 experimental, 12 placebo) completed the study. The global efficacy measure combining scintigraphy and RTOG score favoured the experimental arm (P= 0.07). The RTOG score showed significantly fewer acute side-effects of radiation in the experime…

Peri-implant defect grafting with autogenous bone or bone graft material in immediate implant placement in molar extraction sites-1- to 3-year results of a prospective randomized study.

Objectives To evaluate the survival rate, the orobuccal bone resorption and stability of peri-implant hard and soft tissues following immediate implant placement of wide diameter implants in molar extraction sites and peri-implant defect grafting with autogenous bone (AB) or biphasic bone graft material (BBGM) with 1- to 3-year follow-up examinations. Material and methods Fifty wide diameter implants were placed in 50 patients immediately into molar extraction sockets by a flapless approach. Peri-implant defect augmentation was performed randomized with either AB or BBGM. Primary outcome variable was implant survival. Marginal bone level changes, orobuccal width of the alveolar crest, probi…

Histological evaluation of maxillary sinus floor augmentation with recombinant human growth and differentiation factor-5-coated β-tricalcium phosphate: results of a multicenter randomized clinical trial

Stavropoulos A, Becker J, Capsius B, Acil Y, Wagner W, Terheyden H: Histological evaluation of maxillary sinus floor augmentation with recombinant human growth and differentiation factor-5-coated β-tricalcium phosphate: results of a multicenter randomized clinical trial. J Clin Periodontol 2011; 38: 966–974. doi: 10.1111/j.1600-051X.2011.01754.x. Abstract Objectives: The aim of this prospective, multicenter, randomized clinical trial was to evaluate histologically the outcome of maxillary sinus lift augmentation with a recombinant human growth and differentiation factor-5-coated β-tricalcium phosphate (rhGDF-5/β-TCP) or with a β-TCP and autogenous bone (β-TCP/AB) composite. Material and Met…

Multiple Resistance to Betalactam Antibiotics, Azithromycin or Moxifloxacin in Implant Associated Bacteria

Background Antibiotics are more and more frequently prescribed in dentistry for prevention and treatment of oral diseases. Bacterial resistance to these agents is clearly increasing, including even previously susceptible micro-organisms and true pathogens. The aim of the present investigation was to examine resistant bacterial strains with respect to possible multiple antibiotic resistance. Methods In a previous investigation, implant-associated bacteria were tested first as mixed cultures and again as pure isolates (n = 138) for resistance to one of five antibiotics (ampicillin/AM, ampicillin + sulbactam/AB, azithromycin/AZ, penicillin/PG, moxifloxacin/MX) using the Etest. The resistance o…

The number of intratumoral dendritic cells and ?-chain expression in T cells as prognostic and survival biomarkers in patients with oral carcinoma

BACKGROUND Dendritic cells (DCs) are antigen-presenting cells with a unique ability to cross prime T cells and generate strong antitumor responses. This study evaluates the presence and prognostic significance of DCs as well as functional T cells, which accumulate in the microenvironment in patients with oral squamous cell carcinoma (OSCC). METHODS Immunohistochemistry for S-100 positive or p55 positive DCs and for T-cell receptor (TcR)-associated ζ-chain expression in tumor-infiltrating lymphocytes (TILs) was performed in 132 paraffin embedded specimens from patients with primary OSCC. The median clinical follow-up for the patients was 50 months. The numbers of intratumoral DCs or TILs exp…

Clinicopathologic conference: Multiquadrant expansile fibro-osseous lesion in a juvenile

This paper intends to present clinical, radiologic, and histopathologic features of a case of gigantiform cementoma manifesting in a 14-year-old boy, without any familial involvement. He has been followed for 3 years. Further cases from the literature have been reviewed that confirm a similar clinicopathologic picture. This is the first case report that describes "non-familial gigantiform cementoma" after the World Health Organisation's classification of 2005.

A prospective, randomized pilot study on the safety and efficacy of recombinant human growth and differentiation factor-5 coated onto β-tricalcium phosphate for sinus lift augmentation

Objectives: The aim of this prospective, randomized clinical trial was to investigate the potential of recombinant human growth and differentiation factor-5 (rhGDF-5) coated onto β-tricalcium phosphate (β-TCP) (rhGDF-5/β-TCP) to support bone formation after sinus lift augmentation. Material and methods: In total, 31 patients participated in this multicenter clinical trial. They required a two-stage unilateral maxillary sinus floor augmentation (residual bone height <5 mm). According to a parallel-group design, the patients were randomized to three treatment groups: (a) augmentation with rhGDF-5/β-TCP and a 3-month healing period, (b) augmentation with rhGDF-5/β-TCP and a 4-month healing per…

Implant supported dental rehabilitation following segmental mandibular reconstruction- quality of life outcomes of a prospective randomized trial.

Abstract Purpose The primary objective of this study was to assess the difference in quality of life (QoL) in patients with dental rehabilitation using two or four implant-supported overdentures following segmental mandibulectomy defect reconstruction with fibula free flap. Material and methods This prospective, parallel designed, randomized clinical study was conducted with a 1:1 ratio. At baseline, all participants already had fibula flap reconstruction for segmental defects of the mandible and rehabilitation with conventional (non-implant supported) removable partial dentures. The participants were then randomized into two groups. Group I received implant supported overdentures on two im…

Effect of platform switching on crestal bone levels around implants in the posterior mandible: 3 years results from a multicentre randomized clinical trial.

Objective Evaluation of differences in the clinical performance and crestal bone levels between implants restored with single crowns with platform-matched or platform-switched abutments after 3 years. Material and Methods The study enrolled adult patients missing two or more adjacent teeth in the posterior mandible with natural teeth mesial to the implant site. Randomization followed open-flap implant insertion and the corresponding matching or switching healing abutments placed at surgery. Conventional loading was made with cemented crowns. Clinical follow-up took place annually after loading up to 3 years. Bone level changes were measured in standardized radiographs as the variation in cr…

Promotion of osteogenic cell response using quasicovalent immobilized fibronectin on titanium surfaces: introduction of a novel biomimetic layer system.

Purpose Despite the undeniable potential of cell adhesion molecules such as fibronectin to support osteogenic cell responses and consecutive dental implant healing, the most beneficial mode of application onto titanium implant surfaces still requires investigation. Unspecific fibronectin adsorption on titanium dioxide (TiO2) surfaces can result in low-loading, high-desorption rates and protein–metal interactions with impaired biologic activity. The aim of the present study was to monitor the osteogenic cell responses (cell adhesion, proliferation, and differentiation) specifically to fibronectin biofunctionalized TiO2. Materials and Methods An innovative biomimetic streptavidin-biotin layer…

Der Oberkiefer – das schlechtere Implantatlager?

In the maxilla, it is sometimes necessary to use implants to achieve a good prosthetic result. However, an increased failure rate of maxillary implants seems to be a common clinical experience. This experience was investigated in a retrospective statistical analysis. In a retrospective study of 665 patients between 1987 and 1997, 2484 implants were examined. The implants in the upper jaw were compared to those in the lower jaw. Implants with and without autogenous bone grafts and fixtures in patients with alveolar ridge atrophy, tumor, or trauma were explored. In particular, the data obtained from the orthopantomograms after completion of the prosthetic superstructures were controlled for p…

Clinical and esthetic outcome with immediate insertion and provisionalization with or without connective tissue grafting in presence of mucogingival recessions: A retrospective analysis with follow-up between 1 and 8 years

Background Recessions following immediate implant insertion are frequently reported in the literature. Data regarding implant installation in presence of mucogingival recessions are rare. Purpose This study observes soft tissue level changes following immediate implant insertion and provisionalization of implants with or without connective tissue grafts in the anterior maxilla in patients with initial mucogingival recession within a follow-up period between one and eight years. Materials and methods Twenty-six patients with marginal gingival recessions, which were designated for extraction and immediate implant insertion in the anterior zone of the maxilla (13-23), were included. Out of a l…

Primary loading of palatal implants for orthodontic anchorage--a pilot animal study.

Summary Objectives This study aimed at evaluating the clinical performance and osseointegration of short orthodontic implants immediately loaded with orthodontic forces. Material and methods The investigation was designed as an experimental animal study. Eight palatal implants of the Ortho-system® were immediately loaded with 100 cN after palatal insertion in 4 female german shepherd dogs. Xylene orange and calcein green were used for polychrome sequential labelling. Histological preparation utilized the cutting and grinding technique. Outcome variables were clinical implant success, histological osseointegration and bone-to-implant contact rates. Results All (8/8) implants were clinically …

Soft Tissue Healing at One-Piece Zirconia Implants Compared to Titanium and PEEK Implants of Identical Design: A Histomorphometric Study in the Dog

This study aimed to histomorphometrically evaluate the soft tissue reactions of one-piece zirconia implants versus titanium implants in regard to their insertion depth. Four one-piece implants of identical geometry were inserted on each side of six mongrel dogs: an uncoated zirconia implant, a zirconia implant coated with a calcium liberating titanium oxide, a titanium implant, and an experimental implant made of a synthetic material. Using a split-mouth design, they were inserted in both submerged and nonsubmerged healing modes. After 4 months, dissected blocks were stained with toluidine blue to histologically assess the marginal portion of the implant mucosa, apical extension of the barr…

Clinical and Radiological Long-Term Outcome of a Tapered Implant System with Special Emphasis on the Influence of Augmentation Procedures

Background and Purpose: Tapered implant designs aim to improve primary stability and implant survival in soft bone. However, respective clinical long-term data are scarce. Therefore, a clinical and radiological evaluation of the long-term success of a transgingival-supracrestal inserted tapered implant system with special emphasis on the influence of augmentation procedures was conducted. Material and Methods: In a retrospective study design, all in the Department of Oral and Maxillofacial Surgery of the University Medical Centre, Mainz, Germany, between May 2002 and March 2012, placed tapered implants (Straumann TE®, Basel, Switzerland) were analyzed. In this time period, a total of one hu…

Bone Marrow Concentrate and Bovine Bone Mineral for Sinus Floor Augmentation

Purpose: The purpose of this work was to evaluate the potential of substituting autogenous bone (AB) by bone marrow aspirate concentrate (BMAC). Both AB and BMAC were tested in combination with a bovine bone mineral (BBM) for their ability of new bone formation (NBF) in a multicentric, randomized, controlled, clinical and histological noninferiority trial.Materials and Methods: Forty-five severely atrophied maxillary sinus from 26 patients were evaluated in a partial cross-over design. As test arm, 34 sinus of 25 patients were augmented with BBM and BMAC containing mesenchymal stem cells. Eleven control sinus from 11 patients were augmented with a mixture of 70% BBM and 30% AB. Biopsies wer…

Acoustic monitoring of the artificial airway — experimental results

Non-invasive acoustic airway-monitoring was evaluated in an experimental study. Recording amplitude and travel time of acoustic pulse response, an acoustic pattern of airway's geometry was then calculated. Measurements on models and excised human cadaver lungs were performed to discover whether displacement or obstruction of the artificial airway could be detected by its acoustic equivalent. Regression analysis revealed a close correlation between displacement of tracheostomy tubes and the shifting of the acoustic area-distance function (corr. coeff.: 0.97-1) and an adequate correlation between acoustic and planimetrical determination of cross-sectional area within the tubes (corr. coeff.: …

Veränderungen des nasalen Atemwegs durch transversale Distraktion des Oberkiefers

Fragestellung: In dieser Untersuchung sollten die Auswirkungen der transversalen Distraktion des Oberkiefers auf den nasalen Atemweg durch ein nichtinvasives Untersuchungsverfahren beschrieben werden. Es wird damit untersucht, ob die chirurgische Gaumennahterweiterung eine Weitung auch der posterioren Oberkieferbasis erreicht und durch Vergroserung des Nasenklappenquerschnitts eine Normalisierung der nasalen Ventilation gelingen kann. Material und Methode: Bei 8 Patienten mit hochgradigem Schmalkiefer wurde eine transversale Distraktion des Oberkiefers vorgenommen. Vor der Osteotomie und nach Abschlus der Distraktion wurde das Querschnittprofil des nasalen Atemwegs unter lokaler Schleimhaut…

Implants in free fibula flap supporting dental rehabilitation - Implant and peri-implant related outcomes of a randomized clinical trial.

Abstract Objectives The objective of this study was to assess the difference in success rates of implants when using two or four implant-supported-overdentures following segmental mandibular reconstruction with fibula free flap. Methods and designs This prospective, parallel designed, randomized clinical study was conducted with 1:1 ratio. At baseline, all participants already had segmental reconstruction of mandible with free fibula flap. The participants were randomized into two groups: Group-I received implant-supported-overdentures on two tissue-level implants and Group-II received implant-supported-overdentures on four tissue-level implants. Success rates of the implants were evaluated…

Quantification of thrombocyte growth factors in platelet concentrates produced by discontinuous cell separation.

Platelet concentrates (PC) are increasingly used to increase bone regeneration in pre-prosthetic surgery. Although it is generally appreciated that certain growth factors (PDGF, TGF, EGF, and ECGF) are present in thrombocyte preparations, relatively little is known about these components in quantitative terms. The study reported here analysed the amounts of growth factors in PC produced under standard conditions from healthy volunteers. All the blood samples (237 in total) were analysed using Quantikine ELISA kits (R and D). The mean +/- SD platelet count in whole blood from these donors was 262,000+/-58,000/microl, while in PC produced by discontinuous cell separation it was 1.419,000+/-33…

Immediately provisionalized OsseoSpeed(™) Profile implants inserted into extraction sockets: 3-year results.

Objectives A sloped shoulder might improve the congruence between extraction socket and dental implant and may add to a better circumferential support of the peri-implant structures. Therefore, this study evaluates the 3-year clinical outcome (survival and success rates, marginal bone levels, and Pink Esthetic Score (PES)) of immediately inserted and provisionalized OsseoSpeed(™) Profile implants in the anterior maxilla. Material and methods Twenty-one implants were inserted in 16 patients. All implants were immediately placed into extraction sites with and without facial bone deficiencies. A flapless procedure was utilized, and the implants were provisionalized immediately. Facial gaps wer…

Influence of soft tissue grafting, orofacial implant position, and angulation on facial hard and soft tissue thickness at immediately inserted and provisionalized implants in the anterior maxilla.

Background Resorption of hard and soft tissues following immediate implant insertion is frequently reported. Data regarding the influencing factors on facial tissue thickness are rare. Purpose This retrospective study investigated the impact of connective tissue grafting, the orofacial angulation and position of immediately inserted and provisionalized implants on the facial hard and soft tissue thickness in the anterior maxilla within a 1- to 5-year follow-up. Material and methods Implants with the prerequisite of having preoperative and postoperative cone beam computed tomography (CBCT) and a follow-up of 1 to 5 years were included. Facial bone deficiencies were grafted flaplessly with au…

Using ultrasound transmission velocity to analyse the mechanical properties of teeth after in vitro, in situ, and in vivo irradiation.

Ultrasound transmission velocity (UTV) in isotropic material as a measure for the modulus of elasticity was correlated to mechanical properties. Changes in micromechanical properties of radiated teeth and influence of the oral cavity were to be evaluated nondestructively. UTV was measured in extracted teeth after 36 Gy and 62 Gy of in situ (enorally, with no contact to the oral cavity) and in vitro irradiation. Relative to controls, teeth subjected to 62 Gy in vivo showed higher UTV values for dentine and enamel. Sound teeth irradiated with 60 Gy in situ also showed higher UTV values for enamel, whereas dentine values were not significantly different from those of control. The mechanical pr…

Peri-implant parameters in head and neck reconstruction: influence of extraoral skin or intraoral mucosa.

Objective: This study is designed to assess dental implants supporting overdentures in edentulous patients with operated head and neck malignancies using parameters to detect peri-implant disease. Material and methods: Thirty-four implants supporting overdentures in 34 oral cancer patients were examined. Clinical parameters [plaque index, probing depth, bleeding on probing (BOP), origin of peri-implant soft tissue, and amount of irradiation] were recorded, and microbiological identification of periodontal pathogens was carried out by DNA–DNA hybridization. To identify yeast species, the samples were cultivated on Sabouraud agar plates and subsequently identified by API 20C AUX plates. An im…

Comparison of platelet, leukocyte, and growth factor levels in point-of-care platelet-enriched plasma, prepared using a modified Curasan kit, with preparations received from a local blood bank

Abstract The potential use of autologous thrombocytic growth factors to accelerate bone regeneration requires improved methods of isolating platelet-rich plasma (PRP). In addition to discontinuous cell separation, a second method by which PRP is produced at the point-of-care has now become available. In this study, growth factor levels in PRP from these two sources were compared. Whole blood was drawn from 115 healthy donors (73 males, 42 females) aged 21 - 62 years (mean 36, SD 10). The PRP was separated by the blood bank (BB) using the discontinuous cell separation method or at the 'point-of-care' by the so-called 'buffy coat' method (analogous to the Curasan PRP Kit). Growth factor conte…

A Double-Blind Randomized Controlled Trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV Small-Diameter Bone Level Implants in Edentulous Mandibles - Results from a 1-Year Observation Period

Background: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two-implant overdenture has been recommended as the standard of care. The use of small-diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. Purpose: This randomized, controlled, double-blind, multicenter study investigated in a split-mouth model whether small-diameter implants made from Titanium-13Zirconium alloy (TiZr, Roxolid™) perform at least as well as Titanium Grade IV implants. Me…

Ten-Year Retrospective Follow-Up Study of the TiOblast™ Dental Implant

Purpose: Long-term results in the clinical outcome of different implant systems, including high patient numbers and a long follow-up time, are rare. This retrospective study evaluated the cumulative survival rate of a self-tapping, cylindrical implant system with a conical implant-abutment connection after 10 years of prosthetic loading. Materials and Methods: A total of 516 TiOblast™ implants (Astra Tech AB, Molndal, Sweden) were placed in 108 patients. The patients were treated in the Department of Oral and Maxillofacial Surgery, Johannes Gutenberg University, Mainz, Germany, between September 1994 and May 2005. The main indications for implantation were the treatment of edentulous mandib…

BMP-2 and bFGF release and in vitro effect on human osteoblasts after adsorption to bone grafts and biomaterials.

Objectives Combination of scaffolds and growth factors is a promising option for several clinical problems in bone biomaterials. Simplified growth factor loading by adsorption from aqueous solution is one important option for this technology. We evaluated the adsorption followed by PBS rinsing, release and biological effect of transient loading with basic fibroblast growth factor (bFGF) and bone morphogenic protein 2 (BMP-2) on fresh frozen bone, processed bone matrix, collagen, and a ceramic material with immunofluorescence, enzyme-linked immunosorbent assay (ELISA), and qRT-PCR. Materials and methods The study consisted of three in vitro experiments (immunofluorescence, ELISA, and qRT-PCR…

Severe third molar complications including death-lessons from 100 cases requiring hospitalization.

Purpose In this study we investigated patients that were hospitalized due to third molar (M3) complications. Specifically we analyzed frequency, age distribution, and outcome with respect to the M3 clinical status. Patients and Methods We set up a prospective cohort study and included 100 subjects admitted for management of acute M3-associated complications. The clinical status of the M3 was defined as 1 ) prophylactic M3 removal, 2 ) therapeutic (nonelective) M3 removal, or 3 ) M3 present at the time of admission. Outcome variables were clinical infection markers (C-reactive protein, leukocyte counts) and economic parameters (treatment costs, length of hospital stay, and days of disability…

Treatment of injuries to the inferior alveolar nerve after endodontic procedures.

Overextension of filling material into the mandibular canal after root treatment in the lower jaw is a rare but serious complication. Mechanical compression, chemical neurotoxicity and local infection may cause irreversible nerve damage. A report on 11 patients with neurological complaints of the inferior alveolar nerve after endodontic treatment is summarised. The neurological findings are dominated by hypaesthesia and dysaesthesia. Half of the patients reported pain. Hyperaesthesia is found much more rarely. Nearly all the patients had a combination of one or more symptoms. Initial X-rays showed root filling material in the area of the mandibular canal. Nine cases were treated with apicec…

Bone Augmentation in Dental Implantology Using Press-Fit Bone Cylinders and Twin-Principle Diamond Hollow Drills: A Case Series

Background: Bone transplants are mostly prepared with cutting drills, chisels, and rasps. These techniques are difficult for unexperienced surgeons, and the implant interface is less precise due to unstandardized preparation. Cylindrical bone transplants are a known alternative. Current techniques include fixation methods with osteosynthesis screws or the dental implant. Purpose: A new bone cylinder transplant technique is presented using a twin-drill principle resulting in a customized pressfit of the transplant without fixation devices and combining this with the superior grinding properties of a diamond coating. Materials and Methods: New cylindrical diamond hollow drills are used for cu…

Case report: Noonan syndrome with multiple giant cell lesions and review of the literature.

Noonan syndrome with multiple giant cell lesions (NS/MGCL) was recently shown to be a phenotypic variation within the syndromes of the Ras/MAPK pathway and not an independent entity as previously thought. Here we report on a 13-year-old boy with a typical phenotype of NS including atrial septal defect, pulmonic stenosis, short stature, and combined pectus carinatum/excavatum, pronounced MGCL of both jaws, and a de novo mutation in PTPN11, c.236A>G (which predicts p.Q79R). Mutations in PTPN11 are the most frequent cause of NS and p.Q79R is a recurrent mutation in exon 3. Including this patient, 24 patients with molecularly confirmed NS, LEOPARD, or CFC/MGCL syndrome have been reported to dat…

Das basaloide Plattenepithelkarzinom (BSC) der Mundschleimhaut

The basaloid-squamous carcinoma (BSC) that was first described in 1986 by Wain et al. for the head and neck region is a rare distinct variant of squamous cell carcinoma (SCC). The cardinal histopathologic feature is a biphasic cellular pattern of basaloid and squamous components. BSC has been confused with solid adenoid cystic carcinoma (ACC). Although the number of reported cases is small, BSC appears biologically virulent, with a propensity to aggressive local behavior, early regional and distant metastasis, and subsequent poor survival. We report the clinicopathological characteristics of 4 new cases and compare their immunohistochemical features with those of solid ACC and conventional …

Long-term bony integration and resorption kinetics of a xenogeneic bone substitute after sinus floor augmentation: histomorphometric analyses of human biopsy specimens.

In this case series, a systematic histomorphometric analysis of two human bone biopsy specimens was conducted 1 and 5 years after grafting with a xenogeneic bovine bone substitute material (BSM). While the 1-year specimen still showed extensive signs of an active desmal ossification, the specimen after 5 years mainly showed mature lamellar bone without bone turnover or remodeling. A completed bony integration without extensive resorption of the BSM particles could be detected. Altogether, a good integration in the bone with osteoconduction and a high biocompatibility was seen.

Therapiemonitoring mittels 2-[18F]-FDG-Positronenemissionstomographie nach neoadjuvanter Strahlenbehandlung des Mundhöhlenkarzinoms

Die Kombination strahlentherapeutischer und chirurgischer Behandlungsschritte beim Mundhohlenkarzinom erfordert eine fruhe, objektive Bewertung des Bestrahlungserfolgs. Schlechtes radiotherapeutisches Ansprechverhalten verlangt die moglichst umgehende chirurgische Sanierung auch bei hohem Operations- und Narkoserisiko. Eine deutliche Remission unter Strahlentherapie kann dagegen die Fortsetzung der Bestrahlungsbehandlung begrunden. Die vorliegende Studie untersucht daher die Bewertung des Bestrahlungserfolgs anhand der durch Positronenemissionstomographie (PET) bestimmten Glukosestoffwechselaktivitat.

Radiographic evaluation of conical tapered platform‐switched implants in the posterior mandible: 1‐year results of a two‐center prospective study

Abstract Objective Long‐term success of dental implants depends on healthy peri‐implant soft tissues and adequate bone levels. This prospective study aims to assess bone level changes around implants with internal conical connection and platform‐switching abutments in the posterior mandible. Material and methods Adult patients missing at least two teeth in the posterior mandible and with a natural tooth mesial to the implant site received two or three adjacent internal conical connection implants. After a minimum transmucosal healing period of 8 weeks, single crown restorations were cemented over platform‐switching abutments. Changes in marginal bone levels were measured in standardized per…

Peri‐implant marginal bone loss reduction with platform‐switching components: 5‐Year post‐loading results of an equivalence randomized clinical trial

Abstract Aim To compare the clinical performance and marginal bone levels of implants restored with platform‐switching (PS) or platform‐matching (PM) abutments. Materials and Methods Adult patients missing two or more adjacent teeth in the posterior mandible received 2–4 CAMLOG SCREW‐LINE implants and were randomly allocated to the PM or PS group, receiving the corresponding prosthetic components from surgery onwards. Implants were conventionally loaded with single cemented crowns. Patients were followed annually for 5 years. Outcome measures were marginal bone level changes, implant survival, performance of the prosthetic components and clinical parameters plaque index, sulcus bleeding ind…

Neue Erkenntnisse zur Ätiologie der sogenannten Strahlenkaries

Fragestellung Die Atiologie der Strahlenkaries wird trotz vieler Untersuchungen kontrovers diskutiert: Die These einer direkten radiogenen Lasion des Zahnhartgewebes steht der einer indirekten Pathogenese uber die Radioxerostomie gegenuber.

Prevalence and risk factors of bisphosphonate-associated osteonecrosis of the jaw in prostate cancer patients with advanced disease treated with zoledronate.

Abstract Background In addition to other treatments, patients with prostate cancer (pCA) and bone metastasis receive bisphosphonates. Since 2003, a previously unknown side-effect of bisphosphonates—bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ)—has been described, and frequency has since increased. An exact incidence is still unknown. Objectives The aim of this study was to assess the incidence and additional factors in the development of BP-ONJ. Design, setting, and participants From July 2006 to October 2007, patients with advanced pCA and osseous metastasis receiving bisphosphonate therapy in the Department of Urology or Haematology and Oncology at the Johannes-Gutenberg-Un…

Sealing ability of five different retrograde filling materials.

The sealing ability of Amalgam, Harvard-Cement, Diaket, gold-leaf, and Ketac-Endo as retrofilling materials was investigated. Paper cones were fixed with Harvard-Cement in the instrumented roots of 100 extracted human incisors. Apicectomy was performed and a 2-mm-deep retrograde cavity was prepared. Teeth were assigned to five groups (n = 20); each group received a different filling material. Surfaces of the roots were isolated with nail polish. Teeth, were stored in 1% methylene blue dye for 72 h. Roots were sectioned, and the depth of dye penetration was evaluated through a stereomicroscope. Retrofills with Ketac-Endo showed significantly less leakage compared with amalgam. There was no s…

A comparison of three different attachment systems for mandibular two-implant overdentures: one-year report.

Background: There is a lack of clinical studies on the self-aligning attachment system (Locator®; Zest Anchors, Inc. homepage, Escondido, CA, USA) for two-implant-retained overdentures in the edentulous mandible. Therefore, a comparison of the Locator with two traditional designs (a rotational gold matrix and a rubber O-ring type) in clinical 1-year use was conducted. MaterialsandMethods: From 2003 to 2007, 60 patients received two Osseotite® TG Standard implants (BIOMET 3i Implant Innovations, Palm Beach Gardens, FL, USA) in the intraforaminal area of the edentulous mandible. The implants were left unloaded for 3.5 months, randomized to three different attachment systems, and loaded throug…

Infected osteoradionecrosis of the mandible: follow-up study suggests deterioration in outcome for patients with Actinomyces-positive bone biopsies.

Abstract Infected osteoradionecrosis (IORN) is one of the major complications of oral cancer radiotherapy. Recent studies showed a high prevalence of Actinomyces in IORN. In this study, the clinical follow up of IORN patients ( n  = 25; 20 male, 5 female) with regard to Actinomyces detection in the mandible was analyzed. Within 1.6–119 months of follow up, disease control was achieved in almost 90% of the patients with Actinomyces -negative bone biopsies, but only in 25% of the Actinomyces -positive group. The presence of Actinomyces was associated with a significantly higher risk of treatment failure ( P  = 0.004; Fisher's exact test). This held true when the data were controlled for ‘exte…

Reply to Athanassios Kyrgidis, Zisis Teleioudis and Konstantinos Vahtsevanos’ Letter to the Editor re: Christian Walter, Bilal Al-Nawas, Knut A. Grötz, et al. Prevalence and Risk Factors of Bisphosphonate-Associated Osteonecrosis of the Jaw in Prostate Cancer Patients with Advanced Disease Treated with Zoledronate. Eur Urol 2008;54:1066–72

Reflexionsakustische Lagebestimmung von Trachealkanülen

Non-invasive acoustic airway monitoring was evaluated in an experimental study. Recording amplitude and travel time of acoustic pulse response, an area-distance function of the cross sectional dimensions of the endotracheal tube and the adjacent airway was calculated to obtain an acoustic pattern of the airway. Measurements on models and excised human cadaver lungs were performed to discover whether displacement or obstruction of the artificial airway can be detected in the acoustic equivalent. Regression analysis revealed a close correlation between displacement of tracheostomy tubes and the shifting of the acoustic area-distance function (corr. coeff. 0.97-1). Dispersion analysis confirme…

Prevalence of bisphosphonate associated osteonecrosis of the jaws in multiple myeloma patients

Abstract Background Bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ) is an adverse effect of bisphosphonate treatment with varying reported incidence rates. Methods In two neighboring German cities, prevalence and additional factors of the development of BP-ONJ in multiple myeloma patients with bisphosphonates therapy were recorded using a retrospective (RS) and cross-sectional study (CSS) design. For the RS, all patients treated from Jan. 2000 - Feb. 2006 were contacted by letter. In the CSS, all patients treated from Oct. 2006 - Mar. 2008 had a physical and dental examination. Additionally, a literature review was conducted to evaluate all articles reporting on BP-ONJ prevalen…

Zoledronate, ibandronate and clodronate enhance osteoblast differentiation in a dose dependent manner – A quantitative in vitro gene expression analysis of Dlx5, Runx2, OCN, MSX1 and MSX2

Bisphosphonates are widely used in the clinical treatment of bone diseases with increased bone resorption. In terms of side effects, they are known to be associated with osteonecrosis of the jaw (BONJ). There are two groups of bisphosphonates: the nitrogen-containing bisphosphonates, e.g. zoledronate and ibandronate, and the non-nitrogen-containing bisphosphonates, e.g. clodronate. Their impact on bone metabolism seems to differ. The objective of this study was to compare the osteogenic differentiation potency of these two pharmacologic groups. Human osteoblasts were stimulated with zoledronate and ibandronate at concentrations of 5×10(-5) M, 5×10(-6) M and 5×10(-7) M over the experimental …