Gingival hyperplasia around implants in the maxilla and jaw reconstructed by fibula free flap.

A recurring problem during prosthetic rehabilitation following reconstruction by means of a vascularized fibula flap, after ablation of tumors affecting the facial skeleton, is the hyperplastic granulomatous reactive tissue that forms around the prosthetic abutments of the implant. The features of this phenomenon seem to be directly related to the characteristics of the peri-implant tissue and to the material from which the prosthetic abutments are manufactured. Two main ways of avoiding this are proposed. 1) Skin grafts around implants seem to inhibit the overgrowth of granulomatous tissue. 2) Acrylic provisionals should be avoided and substituted with complete metal-ceramic restoration.

Short implants (6mm) vs. vertical bone augmentation and standard-length implants (≥9mm) in atrophic posterior mandibles: a 5-year retrospective study.

This retrospective study compared the 5-year clinical and radiographic outcomes of short implants (6 mm) (short group), and standard-length implants (≥9mm) placed after a vertical augmentation with autologous bone blocks (augmentation group), supporting partial fixed prostheses in the posterior mandible. Forty-five partially edentulous patients were enrolled in the study and evaluated after 5 years: 22 (51 implants) in the augmentation group and 23 (46 implants) in the short group. Eight surgical complications occurred in the augmentation group versus none in the short group (P=0.003). One short implant failed before loading and one standard-length implant failed after 4 years because of peri-implantitis (P=1.0). Eight biological and two prosthetic complications occurred in the augmentation group vs. three biological and three prosthetic complications in the short group (P=0.09 and P=1.0, respectively). A mean marginal bone loss of 1.61±1.12mm in the augmentation group and 0.68±0.68mm in the short group was found (P=0.002). Within the limitations of this study, both techniques resulted in successful clinical results after 5 years, but short implants exhibited less surgical complications and marginal bone loss than standard-length implants placed in augmented bone.

Bacterial concentration fluorescence immunoassay (BCFIA) for the detection of periodontopathogens in plaque.

A bacterial concentration fluorescence immunoassay (BCFIA) was developed to rapidly detect periodontopathic bacteria in human plaque samples. The BCFIA utilized fluorescent-tagged monoclonal antibodies (MAbs) directed against the lipopolysaccharide of selected Gram-negative bacteria. Microorganisms identified in plaque using the BCFIA included Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum. The immunoassay procedure involved combining a patient's plaque sample with a species-specific fluorescein isothiocyanate-labeled MAb and then incubating the mixture in a specialized microtiter plate allowing the MAb to bind to its homologous bacteria. Bound and unbound fluorescent-tagged MAbs were separated by filtration and total bound bacterial fluorescence was determined with a fluorimeter. The relative number of a bacterial species in a given plaque sample was estimated by reference to a standard curve carried through the BCFIA. The BCFIA had a lower detection limit of near 10(4) specific bacterial cells in a mixed bacterial preparation or plaque sample. When compared to cultivable flora procedures in detecting the 4 periodontopathogens, the BCFIA had high levels of statistical sensitivity, 97% to 100%, while statistical specificity ranged between 57% and 92%. There was a 71% to 82% agreement between BCFIA and DNA probe methodology in detecting periodontopathogens in plaque. The BCFIA, when compared to cultivable flora, offers the advantage of evaluating both live and dead bacterial cells in plaque. This may in part, if not fully, explain the lower specificity values of the BCFIA when compared to cultivable flora. Screening plaque samples for periodontopathic bacteria is considerably faster and results in a greater frequency of detection with BCFIA than cultivable flora based methods.

Granular cell ameloblastoma. An immunocytochemical study.

Granular cell ameloblastoma is characterized by nests of large, eosinophilic granular cells. These latter have long been the subject of debate. Two cases of granular cell ameloblastomas have been immunocytochemically stained with a panel of antibodies against human mitochondria, S-100 protein, CD 68, low molecular weight cytokeratins, chromogranin, laminin, vimentin, PCNA, bcl-2 and p-53. Granular cells exhibited a membranous positivity with cytokeratins while the non granular cells of the same tumors showed a diffuse cytoplasmic reactivity. Moreover, granular cells showed marked cytoplasmic positivity with CD68 antiserum only while human mitochondria, as well as S-100 protein antisera, were consistently negative. PCNA, bcl-2 and p-53 did not stain the granular cells. These results allow easy distinction of granular cell ameloblastomas from similar tumors exhibiting granular cell changes and indicate that the granularity in ameloblastoma cells is consequent to lysosomal overload.

[Clinical trial of the activity and therapeutic effectiveness of 3 drugs with diuretic and antihypertensive action]. / Sperimentazione clinica dell'attività e dell'efficacia terapeutica di tre farmaci ad azione diuretica ed antiipertensiva.

The Authors have examined, by statistical analysis of the variance for a three-period cross-over design, the effects of fenquizone, furosemide and chlorthalidone on 24 in-patients affected by hypertension, edematous cardiac, renal and liver diseases. The fenquizone, given at doses of 20 mg/die/os, has shown an hypertensive activity comparable to that of the other two diuretic compounds. Such an activity occurs without secondary effects on the heart rate, the electrolites and acid-base balance and on the other parameters taken into account among which the renal functionality test, uricemia and glycemia. At low doses fenquizone has an hypotensive action without showing the characteristics secondary effects of diuretics so that it can be employed for long-term treatments without any risk.

CAD-CAM prosthetically guided bone regeneration using preformed titanium mesh for the reconstruction of atrophic maxillary arches.

The protocol presented here is intended to minimise the intervention in bone reconstruction surgery when severe atrophy or deformity is present in the maxillary arches. A patient underwent augmentation of an atrophic maxillary arch using titanium mesh and particulate autogenous plus bovine demineralised bone. After computed tomography data elaboration, computer-aided design and computer-aided machining were used to plan the augmentation of bone volume to improve the implant position needed to support the final dental prosthesis. The augmented maxilla was rapidly prototyped in plastic, and the titanium mesh was tested on this model before the surgical intervention. Then, the preformed titanium mesh was implanted in the maxillary arch with bone grafting. The bone was augmented relative to the position of the implants for the definitive fixed implant-supported rehabilitation. The protocol presented here is a viable, reproducible way to determine the correct bone augmentation for the final implant-supported prosthetic rehabilitation.

Successful resolution of juvenile paradental cysts after marsupialization in five consecutive patients.

BACKGROUND: Juvenile paradental cysts typically occur on the buccal aspect of mandibular first and second molars in children aged 6 to 11 years. The cysts may be treated by enucleation, with or without extraction of the involved teeth, or by marsupialization. This report demonstrates the success of a conservative surgical technique (marsupialization) and good outcomes in five juvenile paradental cyst cases. METHODS: Five patients (two males, three females) with a mean age of 8.4 years, complaining of mandibular buccal swelling around the molars, underwent marsupialization of radiolucent lesions involving partially or fully erupted permanent first molars. Clinical, radiographic and histological characteristics led to diagnoses of juvenile paradental cysts. RESULTS: The surgical procedures were simple to perform and resulted in complete remission of the lesions with no complications. The mean follow-up time was 2.8 years. No recurrences were observed, the related teeth developed normally, and complete periodontal healing was achieved. CONCLUSIONS: The surgical marsupialization of juvenile paradental cysts achieved good outcomes without compromising the development of related teeth, and thus may be considered an appropriate treatment for paediatric patients.

Direct metal laser sintering (DMLS) of a customized titanium mesh for prosthetically guided bone regeneration of atrophic maxillary arches.

This study describes a protocol for the direct manufacturing of a customized titanium mesh using CAD-CAM procedures and rapid prototyping to augment maxillary bone and minimize surgery when severe atrophy or post-oncological deformities are present. Titanium mesh and particulate autogenous plus bovine demineralised bone were planned for patient rehabilitation. Bone augmentation planning was performed using the pre-op CT data set in relation to the prosthetic demands, minimizing the bone volume to augment at the minimum necessary for implants. The containment mesh design was used to prototype the 0.6 mm thickness customized titanium mesh, by direct metal laser sintering. The levels of regenerated bone were calculated using the post-op CT data set, through comparison with the pre-op CT data set. The mean vertical height difference of the crestal bone was 2.57 mm, while the mean buccal-palatal dimension of thickness difference was 3.41 mm. All planned implants were positioned after an 8 month healing period using two-step implant surgery, and finally restored with a partial fixed prosthesis. We present a viable and reproducible method to determine the correct bone augmentation prior to implant placement and CAD-CAM to produce a customized direct laser-sintered titanium mesh that can be used for bone regeneration.

[Ultrastructural observations of cat cortical neurons, labeled by the retrograde method, 8 days after injection of horseradish peroxidase]. / Osservazioni ultrastrutturali sui neuroni corticali di gatto marcati per via retrograda dopo 8 giorni dall'iniezione della HRP.

The ultrastructural characteristics of cat's cortical neurons labeled by retrograde transport of horseradish peroxidase (HRP) have been studied; the cats were sacrificed 8 days after the injection of the enzyme. The aim of this study was principally to observe the evolution of neurons in which HRP had been assumed in diffused as well as in granular form - "diffuse-granular HRP neurons" -, or only in diffused form - "Golgi-like neurons" -. The results obtained show the scanty presence of diffuse-granular HRP cells and the contemporary presence of two populations of Golgi-like cells. In this study is underlined the difference between the observations conducted on specimens from cats sacrificed 48 hours or 8 days after the injection of the HRP.

[Importance of sucking stimulation in lactation: ultrastructural aspects of mammary glands in the rat]. / Importanza dello stimolo suzionale nell'allattamento: quadri ultrastrutturali di ghiandola mammaria di ratto.

The Authors refer the results of a study concerning the mammary glands of lactating rats. We made use of rats Wistar subdivided in three groups. Group A: each rat lactates 8 pups. Group B: each rat lactates 4 pups. 8 days before delivery we provided to hide the nipples of a half of breasts with sutures. Group C: They do not lactate. In the 6th day of suckling, after a period of intense suction, we removed the mammary glands. This material was processed for electronic microscopy. Morphological aspects obtained show a difference in development of cytoplasmatic organs specially manifest in R.E.R. and Golgian apparatus.

Changes in the structure of somato-sensitive neurons in cat following retrograde uptake of HRP.

Neurons of cat cerebral cortex, area S1, labelled by retrograde transport of HRP, have been studied by electron microscopy; the animals were sacrificed 48 h after HRP injection. The cells studied are those in which the enzyme is found both in granular and in diffused form in the cytoplasm (diffuse-granular HRP neurons, DGN), or in diffused form in the cytoplasm (Golgi-like labelled neurons, GLN). The observations have shown that the certain recognition of DGN through electron microscopy, requires a comparison with a semithin section adjacent to the ultrathin section since the labelling granules are light-scattering in dark field. Instead the GLN are not light-scattering in dark field but are directly and unmistakably identifiable even by electron microscopy. The DGN are well preserved on the whole in all their organelles; the GLN show a highly damaged aspect in relation to both the Golgi apparatus and the smooth reticulum, to the cytoplasmic organelles and to the nucleus. Our hypothesis is that the latter neurons take on this appearance because of the combined action of: a) the peripheral mechanical lesions caused by the needle and b) the enormous amount of HRP that the cell is forced to take up (through these pathways) because of its lost integrity and because of the large quantity of marker around the axons. In conclusion intracellular HRP is identifiable by electron microscopy only when it is found in diffused form in the cytoplasm.

Establishment and characterization of two human small cell lung carcinoma cell lines.

Two human cellular lines of cancerous small lung cells obtained from biopsies specimens from two patients were characterized in vitro according to cellular morphology, growth modality, caryotype and antigenic profile. In vivo studies were carried out by inoculating the cells into nude mice of both sexes and various ages by different routes in order to study tumorigenicity and metastatic capacity and to identify a biological marker of the malignancy. Results obtained to date suggest that the two cellular lines have different biological properties similar to the classic and the variant form found in literature. A biological marker of the malignancy seems to be the antigenic profile of the cells.

[Intraparotid lesions in HIV infection]. / Lesioni intraparotidee in infezione da HIV.

HIV-related lesions of the parotid region. A case of parotid enlargement in a 43-year-old male with unsuspected HIV infection is reported. Lesions consisted in lymphonodal changes, epi-myoepithelial islands and cysts lined by squamous epithelium. It is suggested that it is possible to recognize an unsuspected HIV infection, when the first clinical involvement is in the parotid region.