Vitamin D Insufficiency/Deficiency in Patients with Recurrent Benign Paroxysmal Positional Vertigo.

BACKGROUND: The aim of this study is to verify if (1) there is a link between hypovitaminosis D and benign paroxysmal positional vertigo, (2) the number of benign paroxysmal positional vertigo relapses decreases after vitamin D supplementation; and (3) benign paroxysmal positional vertigo response to physical therapy improves after hypovitaminosis D correction. METHODS: We enrolled 26 patients with benign paroxysmal positional vertigo and 24 subjects, who never suffered from vertigo, as a control group. All benign paroxysmal positional vertigo patients underwent physical therapy, once a week, until benign paroxysmal positional vertigo resolution. All participants were subjected to a dosage of serum 25(OH) vitamin D. In patients with hypovitaminosis D, we prescribed cholecalciferol. After 3 months of therapy, all patients were asked to undergo a second dosage of serum 25(OH) vitamin D. For each patient, we counted the number of maneuvers required to resolve each episode of benign paroxysmal positional vertigo before and after vitamin D supplementation. RESULTS: Our results suggest that (1) there is a relationship between vitamin D deficiency and the onset of BPPV and (2) hypovitaminosis correction is able to reduce both the number of patients relapsing and the number of relapses per patient. CONCLUSIONS: We have not found a significant effect of vitamin D supplementation as regards the responsivity of benign paroxysmal positional vertigo to physical therapy.

A case of mandible hypoplasia treated with autologous bone graft from mandibular symphysis: Expression of VEGF and receptors in bone regeneration.

The vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) system plays an important role in angiogenesis and osteogenesis during both skeletal development and postnatal bone growth and repair. Indeed, protein expression changes of this system could contribute to craniofacial defects commonly associated with a variety of congenital syndromes. Similarly to other craniofacial bones, mandible arises from neural crest cells of the neuroectodermal germ layer, and undergoes membranous ossification. Here, we report a case of left mandibular hypoplasia in a 42-year-old man treated with autologous bone graft from mandibular symphysis. After 3 months from surgical reconstruction, the protein expression of VEGF and receptors (VEGFR-1, -2 and -3) in regenerated bone tissue was evaluated by immunohistochemistry. At variance with the mandibular symphysis bone harvested for graft surgery, we observed de novo expression of VEGF and VEGFRs in osteoblasts and osteocytes from post-graft regenerating mandible bone tissue. In particular, while VEGFR-1 and VEGFR-3 immunopositivity was widespread in osteoblasts, that of VEGFR-2 was scattered. Among the three receptors, VEGFR-3 was the more intensively expressed both in osteoblasts and osteocytes. These findings suggest that VEGFR-2 might be produced during the early period of regeneration, while VEGFR-1 might participate in bone cell maintenance during the middle or late consolidation period. VEGFR-3 might, instead, represent a specific signal for ectomesenchymal lineage differentiation during bone regeneration. Modulation of VEGF/VEGFR signaling could contribute to graft integration and new bone formation during mandibular regeneration.

Mesenchymal stem cells in post-surgical cavities of large maxillary bone lesions.

BACKGROUND: Recent studies have highlighted that MSCs are capable of regenerating large bone defects when used in combination with bone substitutes and increasing allo-graft osteointegration. We investigated the hypothesis that autologous MSCs may lead to increased bone regeneration and reduced healing time in post-surgical cavities of large maxillary bone lesions. METHODS: This study involved 10 patients (TEST GROUP) (6 males and 4 females). All patients had expansive mandibular lesions larger than 3 cm. From the surgical point of view, the 10 patients were treated with MSCs (withdrawal of the iliac crest bone marrow BMMSs) directly into the post-surgical cavity, without the addition of filler. RESULTS: and radiological data, in the postoperative, were compared to those of patients who did not receive any grafting of MSCs. The 7 patients with mandibular lesions showed a rapid and very good healing with an 85-90% ossification of the major defect at 12 months. CONCLUSIONS: Through the use of stem cells a greater ossification of the residual cavity (85-90%) was observed at 12 months after surgical enucleation in contenitive defects.

Bone graft and mesenchimal stem cells: clinical observations and histological analysis.

Autologous bone, for its osteoconductive, osteoinductive and osteogenetic properties, has been considered to be the gold standard for maxillary sinus augmentation procedures. Autograft procedures bring also some disadvantages: sometimes the limited amount of available intraoral bone makes necessary to obtain bone from an extraoral site, and this carries an associated morbidity. To overcome this problem we started using homologous freeze-dried bone in maxillary sinus augmentation procedures. This bone is industrially processed with γ-irradiation to eliminate its disease transmission potential and it's considered safe, but this treatment also eliminates the osteoinductive and osteogenetic properties, making it just an inert scaffold for regeneration. Mesenchymal stem cells are successfully used in and orthopedic surgery for their amplification potential of healing mechanisms. We assumed that mesenchymal stem cells can restore the osteogenetic and osteoinductive properties in homologous bone grafts. The aim of this study was an histological evaluation of bone regeneration in maxillary sinus elevation using: 1) mesenchymal stem cells engineered freeze-dried bone allografts; 2) freeze-dried bone allografts. Twenty patients (10M, 10F) with a mean age of 55.2 years affected by severe maxillary atrophy were treated with bilateral maxillary sinus floor elevation. For each patient were randomly assigned a "test" side and a "control" side, different from each other exclusively in the composition of the graft material. The "control" sides were composed by corticocancellous freeze-dried bone chips and the "test" sides were composed by corticocancellous freeze-dried bone chips engineered in a bone marrow mesenchymal stem cells concentrate. After three months bone biopsies were performed on the grafts and histological specimens were made in order to evaluate the healed bone from an histological point of view. Histologically all the specimens showed active remodelling signs and all the tissues were free of inflammatory cells. "Control" side specimens showed a substantial persistence of the grafted bone and, with the interposition of connective tissue, a considerable amount of newly formed bone. "Test" side specimens showed a much more represented cellular component compared to the "control" sides. The grafted bone trabeculae, when detectable, were completely imprisoned inside new formed bone, in direct contact with it and without interposition of connective tissue. Freeze-dried bone can be used successfully as graft material in the treatment of maxillary atrophy. The same bone engineered with stem cells showed a greater histological integration potential comparable with autografts histological morphology. Further studies are needed to confirm these hypotheses.

Differential expression of vascular endothelial growth factor in human fetal skeletal site-specific tissues: Mandible versus femur.

Vascular endothelial growth factor (VEGF) is a well-known mediator that signals through pathways in angiogenesis and osteogenesis. Angiogenesis and bone formation are coupled during either skeletal development or bone remodeling and repair occurring in postnatal life. In this study, we examined for the first time the expression of VEGF in human fetal mandibular and femoral bone in comparison with the respective adult tissues. Similarly to other craniofacial bones, but at variance with the axial and appendicular skeleton, during development mandible does not arise from mesoderm but neural crest cells of the neuroectoderm germ layer, and undergoes intramembranous instead of endochondral ossification. By quantitative real-time PCR technique, we could show that VEGF gene expression levels were significantly higher in fetal than in adult samples, especially in femoral tissue. Western blotting analysis confirmed higher protein expression of VEGF in the fetal femur respect to the mandible. Moreover, immunohistochemistry revealed that in both fetal tissues VEGF expression was mainly localized in pre- and osteoblasts. Differential expression of VEGF in femoral and mandibular bone tissues could be related to their different structure, function and development during organogenesis.

Maxillary sinus lift using fresh frozen bone chips in presence of sinus cyst: clinical and histological report.

The reconstruction of edentulous patients with adequate bone volume and density by the use of bone graft and, subsequently, the placement of dental implants has become a viable treatment option with high predictability. According to many authors, maxillary antral cysts are one of the most common benign pathologies of the maxillary sinus, and they also represent an important contraindication to sinus regenerative surgical technique. The authors report a case of maxillary atrophy which is augmented by fresh frozen bone chips in the presence of antral cysts.

Maxillary alveolar ridge reconstruction with monocortical fresh-frozen bone blocks: a clinical, histological and histomorphometric study.

BACKGROUND: This investigation is a clinical and histological assessment of fresh-frozen bone use in the reconstruction of maxillary alveolar ridges. The study evaluates the effectiveness of this material as a bone filler prior the placement of dental implants. PATIENTS AND METHODS: Sixteen patients with atrophic maxillary ridges underwent maxillary reconstruction with fresh-frozen tibial human block grafts prior to implant placement. Sampling procedures were carried out 4, 6 and 9 months later when a bone core was removed from the grafts for histological and histomorphometric analysis. RESULTS: Eighteen blocks were placed, and each patient received either 1 or 2 blocks. During the sampling procedures, all of the grafts were found to be firm in consistency, well-incorporated, and vascularized. A total of 34 implants were placed into the grafts with a minimum of 40-Newton-cm torque in all cases. The follow-up period ranged from 18 to 30 months. No implants were lost. The histological analysis revealed vital bone with mature and compact osseous tissue surrounded by marrow spaces. CONCLUSION: Bone allografts can be used successfully as graft material for the treatment of maxillary ridge defects. This type of bone graft can be used safely in the areas of implant placement as a suitable alternative to autogenous grafts.

Solitary plasmacytoma of the jaw.

BACKGROUND: There is a lack of consensus on the appropriate management of solitary plasmacytoma (SP) of the jaw. The aim of the present investigation was to provide scientific evidence for the optimal management of this disease through a systematic literature review. METHODS: The included articles are published in English from 1948 to March 2011 and describe the population affected by SP of the jaw with site, clinical and radiographic features, special findings, initial diagnosis, treatment, and follow-up. RESULTS: Fifty cases of SP of the jaw were identified. It typically presents as a single osteolytic lesion with no plasmocytosis involvement of bone marrow. Long bones and vertebrae are the most common sites of SP. Rarely, it involves the jaw occurring in only 4% of cases, mainly in the bone marrow-rich areas, angulus and ramus. Solitary plasmacytoma of the jaw has a worse prognosis than multiple myeloma (MM), and in half of the cases, it evolves in MM. CONCLUSIONS: Because SP of bones is an uncommon tumor that rarely involves the jaws, through this article we emphasize early diagnosis and appropriate management to avoid progression to MM.

Peri-implant squamous odontogenic tumor.

Squamous odontogenic tumor (SOT) is a benign, locally infiltrative intraosseous tumor composed of well-differentiated squamous epithelium in a fibrous stroma. It seems to derive from the epithelial rests of Malassez in the periodontal ligament space. It presents an odontogenic origin, involving both the upper and lower maxillary bone, mainly areas without teeth or connective tissue of the odontogenic cysts. Clinically, SOT could be asymptomatic (3 cases), notwithstanding it is mainly characterized by pain, swelling, and tooth/teeth mobility. The most typical presentation of SOT is a slowly growing endobony lesion arising within a single periodontal location. Frequent misdiagnosis concerns either ameloblastoma and squamous cell carcinoma and fibroma. Since its first description in 1975, less than 50 cases have been identified. In light of the few reported cases, there are no consistently recorded clinical and radiographic features of SOT, and there is no predictable sex or site predilection. Diagnosis is predicated on recognition of the histopathologic features of SOT to obviate possible misdiagnosis of malignancy or ameloblastoma.We report the first case of SOT that arose in the vicinity of an implant. Through a meticulous review of literature, we discuss current etiology, pathogenesis, and treatment.

Clinical, histological and histomorphometrical study of maxillary sinus augmentation using cortico-cancellous fresh frozen bone chips.

BACKGROUND: Insufficient bone volume in the posterior maxilla can be a major problem when placing dental implants. One of the goals of sinus augmentation procedures is the creation of sufficient volume of vital bone for the subsequent insertion and complete osseointegration of implants placed in the posterior maxilla. The aim of the present study was a clinical, histological and histomorphometrical analysis of maxillary sinus augmentation using human fresh frozen bone (FFB) allografts for maxillary sinus lift augmentation procedures. METHODS: Fifteen patients were treated with maxillary sinus augmentation using FFB. After three months, a bone biopsy was taken before implant placement in order to evaluate the healed bone from a histological and histomorphometrical point of view. After further three months, all implants were osseointegrated according to radiographic and clinical examinations. Abutment connection was performed and the patients received prosthetic restoration of the missing teeth. RESULTS: Histologically all the specimens showed signs of active remodelling and all the tissues were free of inflammatory cells. After 12 months of assessment, no implants had failed. CONCLUSION: Our findings suggest that FFB is a biocompatible material that can be successfully used for maxillary sinus augmentation.

Modified insertion technique for immediate implant placement into fresh extraction socket in the first maxillary molar sites: a 3-year prospective study.

BACKGROUND: Immediate implant placement after tooth extraction is a predictable solution in various clinical situations. The purpose of this study was to evaluate the predictability of a treatment, including the placement of implants, using a modified insertion technique at the time of maxillary molar extraction. MATERIALS: Sixty-eight patients with a total of 68 teeth scheduled for tooth extraction and immediate implant placement into fresh sockets were included in the study. Implants were positioned just after teeth removal and, in case of necessity, a regenerative therapy was performed at the same time. After a 3-month period of healing, implants were restored with single crown fixed prostheses. RESULTS: All implants restored with single crowns were monitored for 36 months; only, 3 implants failed with a cumulative survival rate of 97.96%. CONCLUSION: The combination of atraumatic extraction of maxillary molars, sufficient residual inter-radicular bone, and the use of appropriate regenerative material at the time of implant insertion, represents a predictable long-term treatment.

Clinical, histological and histomorphometric evaluation of the healing of mandibular ramus bone block grafts for alveolar ridge augmentation before implant placement.

BACKGROUND: Localized bone defects in the maxilla are commonly reconstructed with autologous mono-cortical bone blocks prior to the placement of dental implants. This study presents a clinical, histological and histomorphometric analysis on the use of mandibular ramus block grafts for ridge augmentation. MATERIALS AND METHODS: mono-cortical bone blocks from the mandibular ramus were grafted in 15 patients. The bone grafts were left to heal for period varying from 3 to 9 months. Afterwards, 30 implants were inserted and bone samples were removed for subsequent histological analysis. RESULTS: All the bone grafts were successful and resorption was minimal. There were no implant failures. At graft placement, mean lateral augmentation was 4.6+/-0.73mm, which, later, at the time of implant insertion, reduced to 4+/-0.77mm. Histological evaluation indicated signs of active remodelling in all specimens. However, the grafted bone contained substantial amounts of non-vital bone (NVB) and generally weak neo-vascularization regardless of the time of biopsies. CONCLUSIONS: The outcome of the study suggests that the larger part of osteocytes in mono-cortical bone do not survive grafting and neo-vascularization of non-vital grafted bone is difficult because of the slow remodelling process into new vital.