Specially designed and CAD/CAM manufactured allogeneic bone blocks using for augmentation of a highly atrophic maxilla show a stable base for an all-on-six treatment concept: a case report.

BACKGROUND: In terms of a highly atrophic maxilla, bone augmentation still remains very challenging. With the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) for allogeneic bone blocks, a new method for the treatment of bone deficiencies was created. This case report demonstrates the successful use of two specially designed and CAD/CAM manufactured allogeneic bone blocks for a full arch reconstruction of a highly atrophic maxilla with an all-on-six concept. CASE PRESENTATION: We report the case of a 55-year-old male patient with a highly atrophic maxilla and severe bone volume deficiencies in horizontal and vertical lines. In order to treat the defects, the surgeon decided to use a combination of two allogeneic bone blocks and two sinus floor augmentations. The bone blocks were fabricated from the data of a cone beam computed tomography (CBCT) using CAD/CAM technology. After the insertion of the two bone blocks and a healing period of 7 months, six dental implants were placed in terms of an all-on-six concept. The loading of the implants took place after an additional healing time of 7 months with a screw-retained prosthetic construction and with a milled titanium framework with acrylic veneers. CONCLUSION: The presented procedure shows the importance of the precise design of CAD/CAM manufactured allogeneic bone blocks for the successful treatment of a highly atrophic maxilla. Proper soft-tissue management is one of the key factors to apply this method successfully.

Interantral alveolar ridge splitting for maxillary horizontal expansion and simultaneous dental implant insertion: A case report.

INTRODUCTION: Dental implants present an advanced technique for the rehabilitation of partial or edentulous patients. Tooth loss caused by caries, periodontal disease or systemic factors often results in a decline of the bucco-lingual alveolar ridge dimension. Within one year the initial bone width can be resorbed up to 50%. As a consequence dental implants may be limited for rehabilitation and cannot be performed in a conventional manner because of the risk of dehiscence and fenestrations. Bone blocks, guided bone regeneration (GBR), horizontal osteogenic distraction and bone grafts may be used for augmentation procedures. In case of sufficient vertical bone dimension, an alveolar ridge splitting and augmentation technique (ARST) can be conducted. This case has been reported in line with PROCESS criteria [1]. CASE PRESENTATION: We present a 51-year old female patient, who has had a full denture for about 30 years. The reason for consultation was the demand for a fixed prosthesis. Dental implants in combination of the ARST with GBR allowed us to correct horizontal deformities of the alveolar ridge. DISCUSSION: We discuss the possibility of using the ARST in the interantral region for a full arch rehabilitation of the maxilla with simultaneous dental implant placement in a narrow alveolar ridge. CONCLUSION: The ARST in addition to simultaneous implant placement with a GBR can be successfully used for a full arch rehabilitation of the maxilla in a narrow alveolar ridge.

Evaluation of mandibular calcification on 3D volume images.

OBJECTIVES: Bone and soft-tissue calcifications are often coincidentally diagnosed on digital panoramic radiographs (DPRs). As the use of three-dimensional (3D) images has increased in the past decade for diagnostics in the mandibular region, we evaluated 3D volume images derived from 2D panoramic images to determine if this method is suitable for early detection of calcifications in this region. METHODS: In this study, three investigators retrospectively and independently evaluated 822 DPRs. If one or more calcifications were present, the 3D volume image from that patient was retrospectively evaluated to confirm the incidental findings. A radiographic system with a low-dose mode and a high-resolution 3D-image function was used. The investigators focussed on the most common calcifications, including tonsilloliths (TL), idiopathic osteosclerosis (IO) of the mandible, carotid artery calcifications (CAC), calcified submandibular lymph nodes (hereafter, CSL), and sialoliths of the submandibular salivary gland (SSG). RESULTS: One or more calcifications were identified in 415 (50.5%) DPRs. In total, 718 calcifications were detected, 30.2% of which were TL, 16.3% IO, 11.3% CAC, 8.8% CSL, and 1.7% SSG. Only 287 (39.97 %) of the calcifications were confirmed on 3D volume images; of these, 29.2% were TL, 58.5% IO, 0.2% CAC, and 1.4% SSG. No CSLs were detected. CONCLUSIONS: Not all areas shown on the DPRs were visible in the retrospectively obtained 3D volume images. Whereas DPRs are used to diagnose calcifications such as IO, TL, SSG, CAC, and CSL, the 3D volume images were only useful for confirming the existence of IO, TL, and SSG calcifications.

Undesirable course of an oral implant rehabilitation in a patient with a long history of bulimia nervosa: case report and review of the literature.

BACKGROUND: Bulimia nervosa is an eating disorder resulting in an intended weight loss due to decreased food intake, induced vomiting, or hyperactivity, and is observed frequently between 12 and 25 years of age. One of the complications is early tooth loss. Moreover, since bulimia nervosa patients suffer from increased atrophy of the alveolar processes, oral rehabilitation even with short dental implants may be impossible. In these cases, lateralization or transposition of the inferior alveolar nerve (IAN) followed by implant placement can be useful. CASE PRESENTATION: A 40-year-old woman with a long-lasting history of bulimia nervosa requested a fixed rehabilitation of her partially edentulous mandible. In 2012, a bilateral IAN transposition approach was performed using piezosurgery, and without any postoperative neurosensory alterations. Two years later, bilateral insertion of each two implants was followed by an inflammatory destabilization of the lower left mandible; subsequent to the implant removal, a fracture occurred, and the latter was stabilized by osteosynthesis plates. In 2017, three additional implants were placed, finally providing the patient with a fixed restoration on five implants. CONCLUSION: Eating disorders may have a tremendous impact on both physical condition and oral health, resulting in early tooth loss and severe bone atrophy. IAN transposition is a viable treatment option to enable installing fixed prostheses via dental implants, but the latter will clearly increase the risk of inflammation and interruption of mandibular continuity. Close clinical and radiologic monitoring is mandatory to adequately respond to complications such as peri-implant mucositis, peri-implantitis, osteomyelitis, or concomitant fractures.

Sensory disturbance along the inferior alveolar nerve as a first clinical sign of multiple florid cemento-osseous dysplasia of the mandible-A case report.

INTRODUCTION: Florid cemento-osseous dysplasia (FCOD) is a rare, benign, slow growing, multifocal fibro-osseous tumour originating from the periodontal ligament. The lesion is characterised by regular bone-structure replacement with fibrous tissue and dysplastic bone. The initial characteristics of FCOD, depending on localisation, resemble those of periapical lesions of inflammatory origin, potentially leading to misdiagnosis. In the absence of infection signs, the treatment of choice is conservative therapy with antibiotics and regular follow-up examinations. PRESENTATION OF CASE: We report the case of a 39-year-old Caucasian woman with sensory disturbance along the inferior alveolar nerve for >2 weeks. The involved teeth were vital and the digital orthopantomogram indicated multiple bilateral periapical brightening. Biopsy was indicated to exclude malignancy and to confirm the FCOD diagnosis with predominantly reactive calcification and cell-rich connective-tissue reaction. The sensory disturbances disappeared after the biopsy. Further conservative therapy included regular radiological examinations every 2 years to prevent surgical intervention due to infection risk. DISCUSSION: Sensory disturbances around the nervus alveolaris inferior are well-known complications of dental and maxillofacial operations and of malignant tumours. Sensitivity disorder as a first symptom of fibro-osseous dysplasia has not been previously described. Although uncommon in its clinical behaviour, FCOD was finally diagnosed after thorough clinical, radiological, and histological examinations. CONCLUSION: Paraesthesia combined with FCOD has not been previously described. Correct diagnosis is essential for proper treatment and to avoid further complications even when the clinical symptoms appear unrelated.

Cross-sectional study on the prevalence of carotid artery calcifications, tonsilloliths, calcified submandibular lymph nodes, sialoliths of the submandibular gland, and idiopathic osteosclerosis using digital panoramic radiography in a Lower Austrian subpopulation.

OBJECTIVE: Bone and soft tissue calcifications can often be visualized on panoramic radiographs, thus leading to presumptive diagnoses requiring further examinations. This cross-sectional study determined the prevalence of suspected carotid artery calcifications, tonsilloliths, calcified submandibular lymph nodes, sialoliths of the submandibular glands, and idiopathic osteosclerosis in a Lower Austrian subpopulation. METHOD AND MATERIALS: Digital panoramic radiographs (DPR) taken from 1,042 subjects for other clinical purposes between the years 2013 and 2015 were evaluated, using a standardized template. Chi-square tests and Fisher's exact test were used to evaluate the relationship between the detected calcifications and patient age as well as sex. RESULTS: Radiographic data from 490 men and 552 women (mean age of 49.2 [range 21 to 87] years) were analyzed. Two hundred and twenty calcifications were recorded in 198 subjects (19.0%), of which 100 (50.5%) were female. The mean age of participants with calcifications was 55.8 [SD 14.1] years. Radiopaque structures included carotid artery calcifications (5.7%), tonsilloliths (5.7%), calcified submandibular lymph nodes (3.6%), sialoliths of the submandibular gland (0.9%), and idiopathic osteosclerosis (5.3%) as presumptive diagnoses. In total, 196 calcifications (89.1%) were recorded in patients older than 40 years; no gender-dependent relationship could be revealed. Multiple calcification types were detected in 20 patients (11 women, 9 men). CONCLUSIONS: With a prevalence of 19.0% in the study population, calcifications observed on DPR are more spread than previously reported. Thus, with patients of increasing age, DPR should be regarded as an important tool for basic screening of suspicious calcifications necessitating further diagnostic assessments.

Long-term clinical and radiologic documentation of a maxillary odontogenic myxoma from early clinical signs to implant-supported prosthodontic rehabilitation: Case report and review of the literature.

Odontogenic myxoma (OM) is a non-metastasizing neoplasm of mesenchymal origin, arising in the tooth-bearing areas of the jaws. When regarding the whole spectrum of differential diagnoses for osteolytic jaw lesions, OM constitutes a benign tumor rarely located in the maxilla. Radiographically, displacement of teeth and frequent involvement of the sinus will be found with advanced maxillary OM. The tumor can be removed by means of several techniques, ranging from conservative measures to extended surgical procedures that differ according to type of bone resection and reconstruction of the defect. This report documents 10 years of follow-up in a patient suffering from a Type IV lesion of maxillary OM; with a radiographically proven growth extending into the right maxillary sinus, the patient underwent a segmental maxillectomy. After a tumor-free period of 5 years, the alveolar ridge splitting technique (ARST) was modified to insert dental implants into the horizontally deficient alveolar ridge of the maxilla, and final rehabilitation by means of a conditionally removable prosthetic reconstruction followed. In this paper, the most striking clinical signs of OM with which the dentist should be familiar are reviewed, and we discuss the advantages of segmental maxillectomy in case of an OM, along with the possibility of using ARST, aiming at prosthetic rehabilitation by placement of dental implants in cases of moderate alveolar ridge deficiency after tumor resection.

Long-term observation of a large keratocystic odontogenic tumour of the mandible treated by a single enucleation procedure: A case report and literature review.

INTRODUCTION: Keratocystic odontogenic tumours (KCOTs) are benign lesions of the jaw that are characterised by expansive growth and high rates of recurrence. Herein, we present a novel minimally invasive method for the surgical treatment of KCOTs. CASE PRESENTATION: We present a 49-year-old woman with a rare, large KCOT of the mandible extending from tooth 37 to tooth 47. A single enucleation procedure was selected as the surgical technique combined with a titanium plate. Teeth interfering with the cystic lumen were preserved. The bone surrounding the cyst was partially removed and rinsed with Carnoy's solution. Recurrence was observed 1year later between teeth 43 and 45, and was treated by single enucleation with Carnoy's solution. After the second operation, the teeth interfering with the KCOT still elicited a positive response to dental pulp testing. No further signs of recurrence were observed after a total observation period of 7 years. DISCUSSION: Various surgical interventions have been described for KCOTs. However, a general guideline for a specific surgical intervention has not yet been established owing to the heterogeneity of these tumours. CONCLUSION: Immediate enucleation in combination with a titanium plate offers an effective surgical approach for the treatment of large KCOTs of the mandible without the need for radical tooth removal or resection of the afflicted side.

Large mandibular central odontogenic fibroma documented over 20 years: A case report.

INTRODUCTION: Central odontogenic fibroma (COF) is a rare, benign, slow-growing intraosseous odontogenic tumor, and accounts for 0.1% of all odontogenic tumors. It is often confused with other entities, such as keratocysts, ameloblastomas, and odontogenic myxomas. Complete enucleation followed by curettage is the treatment of choice for COF to ensure the lowest possible chance of recurrence. CASE PRESENTATION: We report the case of a young Caucasian woman with COF that went undiagnosed for several years despite repeated radiologic examinations. Finally, a massive tumor was surgically removed and the wound was curetted. The specimen was histologically confirmed to be a COF. The patient remains under regular follow-up, and thus far there have been no clinical or radiologic signs of recurrence. DISCUSSION: This rare case of COF, which was documented over a period of 20 years, has helped us to describe the features of this tumor. It also confirms that adequate surgical treatment can lead to impressive bone regeneration in healthy individuals, as evident from the radiologic findings acquired before, during, and after enucleation of the COF in our patient. Our findings also confirm the view that COF has a favorable prognosis regardless of its final size. CONCLUSION: Early diagnosis is key to successful treatment of COF. The slow but steady increase in the size of a COF with no accompanying symptoms has not been reported previously. To our knowledge, this is the only documented case of a COF that has been under continuous radiologic observation for over 20 years.

Effect of different biomaterials on the expression pattern of the transcription factor Ets2 in bone-like constructs.

Tissue engineering offers an exciting prospect for reconstructive surgery by replacing missing natural scaffolds with artificial ones. For optimal success the artificial scaffold should provide an environment closely resembling the natural tissue. Little is known about the direct influence of the scaffold on the expression of regulators of bone development, such as transcription factors. The aim of this study was to investigate the influence of the scaffold material on the expression of V-ets erythroblastosis virus E26 oncogene homolog 2 (avian) (Ets2), a key transcription factor in bone biology. Human primary bone precursor cells were seeded in three-dimensional constructs consisting of hydroxyapatite (HA) or poly (lactic-co-glycolic acid) (PLGA). Cells grown on tissue culture polystyrene dishes served as controls. After cultivation for up to 21 days the expression of Ets2 and other important bone-specific genes was assessed by reverse transcription polymerase chain reaction (RT-PCR) and Western Blotting. Ets2 mRNA showed significantly higher expression in controls than in bone-like constructs, and more Ets2 mRNA was expressed in cells grown in HA than in PLGA constructs. At protein level however, Ets2 expression was higher in constructs than in controls after prolonged culture. Our study showed for the first time a differential expression of Ets2 in tissue engineered bone constructs in vitro, demonstrating that scaffold chemistry has an influence on the expression of genes regulating osteogenesis.

Phenothiazine chloride and soft laser light have a biostimulatory effect on human osteoblastic cells.

OBJECTIVE: Low-level laser therapy (LLLT) is a well accepted tool to accelerate wound healing and to reduce inflammation after oral implant insertion. Since there are no in vitro data on a combination of LLLT with prior photosensitization, it was the aim of this study to investigate if photosensitization with phenothiazine chloride results in an alteration of the biostimulatory effect of low-level laser irradiation. BACKGROUND DATA: LLLT and antimicrobial photodynamic therapy are well established for the treatment of peri-implantitis. In vitro studies have shown a biostimulatory effect of LLLT on various cell types, including osteogenic cells. MATERIALS AND METHODS: SaOS-2 cells were treated with the photosensitizer phenothiazine chloride before irradiation with matched laser light. At 24-h intervals the viability and differentiation were analyzed in treated and untreated cells. RESULTS: While the biostimulatory effect of the LLLT could be observed for the lower irradiation dose, the pretreatment with phenothiazine chloride did not significantly affect the growth and differentiation of the SaOS-2 cells. CONCLUSION: It can thus be concluded that combined treatment with phenothiazine chloride and LLLT does not result in a synergistic enhancement of the biostimulatory effect of LLLT, but there was also no evidence for antagonizing effects on growth and differentiation of human osteoblasts.

Potential involvement of MYC- and p53-related pathways in tumorigenesis in human oral squamous cell carcinoma revealed by proteomic analysis.

Oral squamous cellular carcinoma is a malignant tumor with poor prognosis. Discovery of early markers to discriminate between malignant and normal cells is of high importance in clinical diagnosis. Subcellular fractions from 10 oral squamous cell carcinoma and corresponding control samples, enriched in mitochondrial and cytosolic proteins, as well as blood from the tumor were analyzed by proteomics, two-dimensional gel electrophoresis, followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Three-hundred and fifty different gene products were identified. Twenty proteins showed deranged levels in oral squamous cell carcinoma in comparison with the control samples and are potentially involved in tumor growth and metastasis. Of these, 16 proteins were upregulated. By applying pathway analysis, we found 8 of the upregulated gene products to be linked to three main locus genes, p53, MYC, and MYCN, and could be candidate biomarkers for OSCC. The findings of this pilot study show that OSCC gene ontology combined with proteomic analysis is a powerful tool in systems biology for the elucidation of the complexity of expression profiles in cellular processes. Application of such pathway analysis has the potential to generate new insights into complex molecular mechanisms underlying disease related processes and could therefore significantly contribute to the efficient performance of the entire discovery process.

Initial effects of low-level laser therapy on growth and differentiation of human osteoblast-like cells.

Low-level laser therapy is a clinically well established tool for enhancement of wound healing. In vitro studies have also shown that low level laser therapy has a biostimulatory effect on cells of different origin. The aim of this in vitro study was to investigate the initial effect of low-level laser therapy on growth and differentiation of human osteoblast-like cells. SaOS-2 cells were irradiated with laser doses of 1 J/cm2 and 2 J/cm2 using a diode laser with 670 nm wave length and an output power of 400 mW. Untreated cells were used as controls. At 24 h, 48 h and 72 h post irradiation, cells were collected and assayed for viability of attached cells and alkaline phosphatase specific activity. In addition, mRNA expression levels of osteopontin and collagen type I were assessed using semi-quantitative RT-PCR. Over the observation period, cell viability, alkaline phosphatase activity and the expression of osteopontin and collagen type I mRNA were slightly enhanced in cells irradiated with 1 J/cm2 compared with untreated control cells. Increasing the laser dose to 2 J/cm2 reduced cell viability during the first 48 h and resulted in persistently lower alkaline phosphatase activity compared with the other two groups. The expression of osteopontin and collagen type I mRNA slightly decreased with time in untreated controls and cells irradiated with 1 J/cm2, but their expression was increased by treatment with 2 J/cm2 after 72 h. These results indicate that low-level laser therapy has a biostimulatory effect on human osteoblast-like cells during the first 72 h after irradiation. Further studies are needed to determine the potential of low-level laser therapy as new treatment concept in bone regeneration.

Expression patterns of Ets2 protein correlate with bone-specific proteins in cell-seeded three-dimensional bone constructs.

The transcription factor Ets2 and its transcriptional targets osteopontin (OPN) and osteocalcin (OC) are expressed in tissue-engineered bone constructs in vitro. Up to now little is known about the role of Ets2 in tissue-engineering applications. This study was intended to investigate the hypothesis that protein expression of Ets2 is correlated with the expression of bone-specific proteinsin tissue-engineeredbone constructs. Cell-seeded three-dimensional bone constructs manufactured with osteoblastic cells and poly(lactic-co-glycolic acid) polymer fleeces over a period of 21 days were analyzed by SDS-PAGE and Western blotting. The protein expression of OPN, OC, osteonectin and collagen type I was analyzed. Cellularity, alkaline phosphatase-specific activity and histology confirmed the osteoblastic phenotype of the constructs. Correlations between Ets2 expression and OPN and Ets2 and collagen type I expression could be detected during the phase of late osteoblastic differentiation between days 9 and 21. The correlation between OC and collagen type I was significant in this late stage of osteoblastic differentiation. These results suggest that there is a strong interplay of Ets2 with bone-specific proteins in cell-seeded three-dimensional bone constructs. This study is a crucial step to elucidate the complex interplay of bone-related proteins in the application of bone tissue engineering.