Roberto Sacco

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.

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.

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.

Implant-supported restoration of congenitally missing teeth using cancellous bone block-allografts

BACKGROUND AND OBJECTIVE Patients with congenitally missing teeth may present with undeveloped alveolar bone morphology, making implant reconstruction a challenge. The aim of the present study was to evaluate the outcome of dental implants after ridge augmentation with cancellous freeze-dried block bone allografts in patients with congenitally missing teeth. STUDY DESIGN Twelve patients with a mean age of 21 ± 4 years, were included. Congenitally missing teeth included maxillary lateral incisors, a maxillary canine, and mandibular central and lateral incisors. A bony deficiency of ≥3 mm horizontally and ≤3 mm vertically according to computerized tomography served as inclusion criteria. Twenty-one implants were inserted after a healing period of 6 months. Five out of 21 implants were immediately restored. Bone measurements were taken before bone augmentation, during implant placement, and at second-stage surgery. RESULTS Nineteen cancellous allogeneic bone-blocks were used. The mean follow-up time was 30 ± 16 months. Bone block and implant survival rates were 100% and 95.2%, respectively. Mean bone gain was statistically significant (P < .001): 5 ± 0.5 mm horizontally and 2 ± 0.5 mm vertically. All of the patients received a fixed implant-supported prosthesis. Soft tissue complications occurred in 4 patients (30%). Complications after cementation of the crowns were seen in 1 implant (4.8%). All implants remained clinically osseointegrated at the end of the follow-up examination. There was no crestal bone loss around the implants beyond the first implant thread. CONCLUSION Cancellous bone block-allografts can be used successfully for implant-supported restorations in patients with congenitally missing teeth.

A systematic review of microsurgical reconstruction of the jaws using vascularized fibula flap technique in patients with bisphosphonate-related osteonecrosis

OBJECTIVE The aim of this systematic review was to assess the role of microsurgical reconstruction of the jaws in patients with bisphosphonate-related osteonecrosis, and biological complications after an observation period of at least 12 months. MATERIAL AND METHODS An electronic MEDLINE search supplemented by manual searching was conducted to identify studies reporting data of at least 12 months observation on the microsurgical reconstruction of the jaws in patients with bisphosphonate-related osteonecrosis. RESULTS Four studies resulted eligible for the analysis yielded. Three out of five studies were free of complications, with a success rate of 100% as no recurrence of osteonecrosis was registered. CONCLUSIONS Microsurgical reconstruction of the jaws represents a valid treatment modality in patients with bisphosphonate-related osteonecrosis at 3rd stage of the disease.

Full-mouth rehabilitation with immediate loading of implants inserted with computer-guided flap-less surgery: a 3-year multicenter clinical evaluation with oral health impact profile.

Objective:The purpose of this report is to present the clinical outcomes and patients’ satisfaction of full-mouth rehabilitation using computer-aided flapless implant placement and immediate loading of a prefabricated prosthesis. Materials and Methods:The study included 30 consecutive fully edentulous patients who received 312 implants. Mandible and maxilla were treated in the same surgical session with computer-guided flapless approach using the NobelGuide protocol. Prefabricated screw-retained fixed prostheses were inserted at the end of surgery. Clinical and radiographic evaluations were assessed at 6, 12, and 36 months. At baseline and 6 months after surgery, patients answered Oral Health Impact Profile in Edentulous Adults questionnaire to assess satisfaction. Results:The implant survival rate was 97.9%, whereas the average marginal bone loss was 1.9 ± 1.3 mm after 3 years. At 6 months, patients showed significantly greater satisfaction with their fixed rehabilitation when compared with conventional dentures. Conclusions:The results of this study confirm that rehabilitation with a prefabricated fixed prosthesis supported by implants placed with NobelGuide protocol is a viable and predictable treatment and increases patients’ satisfaction and improves oral health-related quality of life.

Post-Traumatic Implant-Supported Restoration of the Anterior Maxillary Teeth Using Cancellous Bone Block Allografts

PURPOSE To prospectively evaluate the outcome of dental implants placed in the post-traumatic anterior maxilla after ridge augmentation with cancellous freeze-dried block bone allografts. MATERIALS AND METHODS Patients presenting with a history of anterior dentoalveolar trauma with bony deficiencies in the sagittal (≥3 mm) and vertical (<3 mm) planes according to computed tomography were included. The recipient sites were reconstructed with cancellous bone block allografts. After 6 months of healing, implants were placed. The primary outcomes of interest were 1) bone measurements taken before grafting, at the time of implant placement, and at stage 2 operations; 2) implant survival; and 3) complications. RESULTS The sample was composed of 20 consecutive patients with a mean age of 25 ± 7 years. We used 28 cancellous allogeneic bone blocks, and 31 implants were inserted. Of the 31 implants, 12 were immediately restored. The mean follow-up was 42 ± 15 months. Graft and implant survival rates were 92.8% and 96.8%, respectively. Mean bone gain in the sagittal and vertical planes was 5 ± 0.5 mm horizontally and 2 ± 0.5 mm (P < .001). Successful restoration was achieved in all patients with fixed implant-supported prostheses. Soft tissue complications occurred in 7 patients (35%). Complications after cementation of the crowns were seen in 3 implants (9.6%). All implants remained clinically osseointegrated at the end of the follow-up examination. There was no crestal bone loss around the implants beyond the first implant thread. CONCLUSION Cancellous block allograft can be used successfully for post-traumatic implant-supported restoration in the anterior maxilla.

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.

Solitary plasmacytoma of the jaw.

BackgroundThere 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. MethodsThe 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. ResultsFifty 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. ConclusionsBecause 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.