Rehabilitation of the severely atrophied dentoalveolar ridge in the aesthetic region with corticocancellous grafts from the iliac crest and dental implants

Background

The aim of this study was to assess changes in bone volume after block bone augmentation and placement of dental implants and further evaluate the aesthetic outcome of the treatment.

Material and Methods

9 Patients with atrophied anterior maxilla were included in this study. They received total of 21 implants. Dimensions of the alveolar ridge were measured from cone-beam computed tomography x-rays. The bone level at the implant sites was analysed from intraoral x-rays and the aesthetic outcome was assessed from clinical photographs using a pink aesthetic score (PES) scaling.

Results

The mean gained horizontal bone width at the marginal crest and 5 mm apically was accordingly 2.7mm and 5.0 mm. The mean PES rating was 9.8/14. The survival rate of.

Conclusions

Reconstruction of the atrophied anterior maxilla with bone blocks and dental implants is a safe procedure with high survival rate and acceptable aesthetic outcome.

Key words:Dental implants, aesthetic region, corticocancellous bone grafts, pink aesthetic score, survival rate.

The use of anatomically drop-shaped bioactive glass S53P4 implants in the reconstruction of orbital floor fractures--A prospective long-term follow-up study

An isolated fracture of the orbital floor needs reconstruction if there is a clear herniation of adipose tissue or of the rectus inferior muscle into the maxillary sinus. A prospective study was carried out treating 20 patients with an isolated blow-out fracture of the orbital floor or with a combined zygomatico-orbito-maxillary complex fracture, using a newly designed anatomically drop-shaped implants made of bioactive glass (BAG) S53P4. Computed tomography (CT) was performed immediately postoperatively to confirm the correct position of the plate. The patients were followed up for an average of 32 months clinically and radiologically with magnetic resonance imaging (MRI) for an average of 31 months. None of the patients had any signs of complications related to the implant and the clinical outcome was very good. None of the patients had persisting diplopia. The level of the pupillas was normal in 15 of 20 patients. Minor hypo-ophthalmos ranging from 0.5 to 1.0 mm was observed in three patients, and moderate hypo-ophthalmos of 2.0 mm was seen in one patient. Hyperophthalmos of 1.0 mm was seen in one patient. Minor enophthalmos on the operated side ranging from 0.5 to 1.0 mm was seen in eight patients. Mild to moderate paraesthesia of the infraorbital nerve was observed in six patients. The immediate postoperative CT and the long term follow-up MRI revealed that the drop-shaped BAG implants retained their correct position in the orbital floor and did not show any evidence of losing their original shape or material resorption. No adverse tissue reaction was associated with the material. Due to the anatomical drop shape, the implants could successfully maintain the orbital volume and compensate for the retrobulbar adipose tissue atrophy.

Anti-tumor necrosis factor treatment in cherubism--clinical, radiological and histological findings in two children

Cherubism is a rare and disfiguring genetic disorder with excessive bone resorption and multilocular lesions in the mandible and/or maxilla. The disease-causing gain-of-function mutations in the SH3-binding protein 2 (SH3BP2) gene result in increased myeloid cell responses to macrophage colony stimulating factor and RANK ligand, formation of hyperactive osteoclasts (giant cells), and hyper-reactive macrophages that produce excessive amounts of the inflammatory cytokine tumor necrosis factor α (TNF-α). Recent findings in the cherubism mouse model suggest that TNF-α plays a major role in disease pathogenesis and that removal of TNF-α prevents development of the bone phenotype. We treated two children with cherubism with the TNF-α antagonist adalimumab for approximately 2.5 years and collected extensive clinical, radiological and histological follow-up data during the treatment. Histologically the treatment resulted in a significant reduction in the number of multinucleated giant cells and TNF-α staining positivity in both patients. As evaluated by computed tomography and magnetic resonance imaging, the lesions in Patient 1 showed either moderate enlargement (mandibular symphysis) or remained stable (mandibular rami and body, the maxilla). In Patient 2, the lesions in mandibular symphysis showed enlargement during the first 8 months of treatment, and thereafter the lesions remained unchanged. Bone formation and resorption markers remained unaffected. The treatment was well tolerated. Based on our findings, TNF-α antagonist may decrease the formation of pathogenic giant cells, but does not result in lesion regression or prevent lesion expansion in active cherubism. TNF-α modulator treatment thus does not appear to provide sufficient amelioration for patients suffering from cherubism.

Local primary (AL) amyloidosis in the palate

Oral amyloidosis is usually presented in the tongue and is often regarded as a paraneoplastic phenomenon. We present a rare case of primary local amyloidosis in the palate of an 80-year-old male. No simultaneous general illnesses or malignancies were detected in spite of extensive assessments by specialists in internal medicine.

Bioactive glass S53P4 in repair of septal perforations and its interactions with the respiratory infection-associated microorganisms Haemophilus influenzae and Streptococcus pneumoniae

Interpositional grafts between mucoperiosteal flaps are commonly used in the repair of septal perforations. We studied the use of bioactive glass (BAG) S53P4 as an interpositional graft in 11 patients suffering from septal perforations. In aqueous environments, ions are released from the BAG and the pH rises in its vicinity, both of which may influence the growth and adhesion of microorganisms. Thus, we also studied the effects of the BAG S53P4 as granules or discs on the respiratory infection-associated microorganisms Haemophilus influenzae and Streptococcus pneumoniae. Growth inhibition was studied using an agar plate test and adhesion was analyzed both with and without serum precoating of the BAG S53P4. The perforations were successfully closed in 10 of 11 patients. One patient had a near total septum perforation, which could not be closed. No BAG-associated infections were seen during the follow-up. The BAG S53P4 did not show any clear growth inhibition of the microorganisms, which showed low adhesion to the material. Serum precoating increased the adsorption. Thus, uncoated BAG S53P4 seems to be a good graft in the repair of septal perforations.

Interactions between the bioactive glass S53P4 and the atrophic rhinitis-associated microorganism klebsiella ozaenae

In an aqueous environment, ions are released from a bioactive glass (BAG) and the pH rises in its vicinity. This may influence both growth and colonization of microorganisms. We studied the effects of the BAG S53P4 on the atrophic rhinitis-associated microorganism Klebsiella ozaenae. The glass was used in the form of granules or discs. Growth inhibition was studied using an agar plate test. Adhesion was studied by incubating bacterial suspension with the glass. The effect of the presence of the bacteria on the formation of the Si-rich layer on the bioactive glass was also analyzed. Furthermore, a follow up study of 19-74 months with ozena patients surgically treated with the BAG S53P4 was performed. The bioactive glass showed no clear growth inhibition of K. ozaenae in the agar plate test. K. ozaenae showed low adherence to the BAG S53P4. No growth of the microbe was seen on the glass during the 8 h incubations and the Si-rich layer was formed normally. The clinical follow-up study showed no infections of the implants and the symptoms of the patients were markedly reduced. Thus, the BAG S53P4 did not favor adhesion and colonization of K. ozaenae, in vitro, which is supported by the in vivo findings showing no BAG-associated infections or reinfections.

Antibacterial effects of a bioactive glass paste on oral microorganisms

Bioactive glasses contain oxides of calcium, sodium, phosphorus, and silicon in a proportion that provides the material with surface activity and concomitantly with the property of forming a strong bond with bone. Bioactive glasses have been tested as bone substitutes in different clinical situations. In an aqueous environment, Ca2+, Na+, PO4(3-) , and Si4+ are released from the glass, resulting in a rise in pH and in osmotic pressure in its vicinity. Since these are factors that potentially influence the viability of oral microorganisms at the dentogingival margin, we studied the effects of bioactive glass S53P4 on the oral microorganisms Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Actinomyces naeslundii, Streptococcus mutans, and Streptococcus sanguis. This was done by incubating each microbe in a suspension, in the presence of bioactive glass S53P4 in powder form. A. naeslundii was found to lose its viability within 10 min under the experimental conditions. A. actinomycetemcomitans, P. gingivalis, and S. mutans lost their viability within 60 min. Also for S. sanguis a significant loss of viability was seen within 60 min, but it was the only microbe that had any viable cells left after 60 min. Thus, in aqueous solutions the powdered bioactive glass S53P4 appears to have a broad antimicrobial effect on microorganisms of both supra- and subgingival plaque. Consequently, it could be useful as an ingredient in tooth-care products that may have beneficial effects on oral health both from a cariologic and a periodontal point of view.