Dental implants with locking taper connection versus screwed connection: microbiologic and scanning electron microscope study.

The aim of this study is to carry out an analysis of the Fixture-Abutment Interfaces (FAI), comparing different connection systems, to evaluate the role of geometric discrepancy, which is present between the abutment and the fixture, in favoring the permeability to bacterial colonization. Two types of commercially available FAI were studied, 16 screwed FAI (Sweden-Martina Italia) (4 of Ø 3.8 mm diameter, 4 of Ø 4.7 mm diameter, 4 of Ø 5.7 mm diameter and 4 of Ø 6.7 mm diameter) and 4 FAI (Bicon) (Ø 3.5mm diameter). The assays were carried out in vitro, placing the different dental implants in contact with broth culture of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Streptococcus pyogenes to test the infiltration inside the FAI. Furthermore, scanning electron microscope (SEM) analysis was carried out to evaluate the gap at the fixture-abutment interface. In all the locking taper FAI and in the screwed FAI with a diameter of 3.8 mm there was no trace of bacterial infiltration of the species examined. In the screwed FAI with a diameter of 4.7 mm, 5.7 mm and 6.7 mm there was an increasing level of bacterial infiltration in relationship to the diameter. Therefore, this paper shows that there exists an important correlation between the diameter of the screwed implant and the permeability to microbic infiltration that is directly proportional to the diameter of the implant.

Gingival overgrowth in renal transplant recipients induced by pharmacological treatment. Review of the literature.

Patients who undergo a renal transplant also require a pharmacological immunosuppressor therapy with cyclosporine (CsA) as well as anti-hypertensive calcium channel-blockers (CCBs); the former suppresses interferon and interleukin-2 production thus interfering with T cell cell-mediated activity, while the latter are used in order to counteract the nephrotoxicity of CsA which causes the local release, of thromboxane A2 with vascular vasoconstriction in the kidney. The use of both these drugs, particularly if used in association, leads to the onset of a clinical picture of variable entity, characterized mainly by a hypertrophy originating usually at the level of interdental papillae, and more pronounced in the anterior maxillary areas and the vestibular surfaces of the teeth, in a more or less symptomatic manner. The therapy is above all preventive, with an appropriate oral hygiene program, both professionally as well as at home, and with the use of substitutive drugs that do not present such side effects.

Local delivery of antimicrobial drugs in the treatment of chronic adult periodontitis.

AIM: The aim of this study was to evaluate the clinical and microbiologic results of local delivery of adjunctive antimicrobials in the treatment and management of patients with periodontitis. METHODS: The study population included 33 patients (age range, 37-49 years), with chronic adult periodontitis. Eleven of 33 received local treatment with 10% doxycycline injected directly into the periodontal pocket; 11 received local treatment with a chlorhexidine-based gel (1.5%) in situ; 11 received mechanical treatment with scaling and root planing. The crevicular fluid of the doxycycline-treated group was analyzed using high performance liquid chromatography over a period of 1 month. RESULTS: In the 11 patients treated with an antibiotic we observed a reduction in attachment loss and a reduction in probing depth of 1.4 mm; in the 11 chlorhexidine-treated patients we observed a reduction in attachment loss and a reduction in probing depth of 0.9 mm; in the remaining 11 patients the reduction in attachment loss and probing depth was less than those measured in the other two treatment groups. CONCLUSIONS: Our results suggest that direct delivery of antimicrobial agents to the infection site may be a useful adjunctive to conventional periodontal treatment.

Implant surface and osseointegration.

Oral rehabilitation by means of osteointegrated implants is gaining more and more importance, in particular due to the improved characteristics of the fixture: among these, the superficial microscopical morphology plays a role of primary importance, since it can influence the evolution of the osteointegrative process. Therefore, this led to many surface treatments which can improve the quality and the speed of formation of the bony tissue. The aim of this paper is a review of the literature on this topic in order to find out which processes of characterization of the surface implant are now available and which results can be obtained.

Drugs in oral surgery. Brief guidelines for adult patients.

Drugs administrable in oral surgery for adult patients are antiseptics-antibiotics, antiinflammatory-analgesics and sedative-hypnotics. Such drugs can be administered before, during or after oral surgery. Sedative-hypnotics can be administered before or during oral surgery in order to control the patient's anxiety. Anti-inflammatory-analgesics, on the other hand, can be administered before or after oral surgery to lower edema and pain. For this purpose, FANS are the most commonly used drugs but, in more traumatic oral surgery, the administration of a single pre-surgery dose of corticosteroids is suitable. As regards, antibiotics have to be given from 15 min to 1 h before oral surgery and continued or otherwise for 24-48 h depending on the dosage. post-surgery infection onset, in fact, is higher within 3 h after oral surgery.

[Alveolar ridge augmentation by means of onlay grafts harvested from mandibular symphysis]. / Correzione di creste ossee edentule mediante prelievi a onlay dalla sinfisi mentoniera.

AIM: Prosthestic-implant rehabilitation in subjects partially, or totally, endentulous is the method of choice for the considerable advantages involved from an aesthetic as well as functional point of view, besides preventing the physiological reabsorption that is established in the edentulous area. However, it is necessary to have an adequate quantity, as well as quality, of bone in order to support the fixture and the masticating load, conditions that up to now could often prove inferior for various reasons. Such a randomized research programme was proposed, in order to increase the bone volume by means of grafted onlays in the mandibular/chin area, with implant positioning 6 months after the operation, as a valid solution to the prosthestic problems found in the bone deficiency area. METHODS: Twenty patients with partial edentulism in the incisor-canine area were chosen. They showed no signs of periodontal diseases, bruxism or parafunctions. They underwent an autogenesis bone graft with the bone being taken from the mandibular/chin area, with positioning of the implant 6 months after the first operation, thus obtaining an increased bone height of 5 to 7 mm. RESULTS: Check ups were carried out in the 1(st) week after surgery, once a month for the first 3 months and then every 6 months and showed a minimal degree of bone reabsorption and an excellent osteo-integrative process. CONCLUSION: The use of onlay autogenous bone, compared to the other methods for increasing bone volume, is a valid solution for prosthetic-implant rehabilitation in edentulous areas.