Osteoimmune regulation underlies oral implant osseointegration and its perturbation.

In the field of biomaterials, an endosseous implant is now recognized as an osteoimmunomodulatory but not bioinert biomaterial. Scientific advances in bone cell biology and in immunology have revealed a close relationship between the bone and immune systems resulting in a field of science called osteoimmunology. These discoveries have allowed for a novel interpretation of osseointegration as representing an osteoimmune reaction rather than a classic bone healing response, in which the activation state of macrophages ((M1-M2 polarization) appears to play a critical role. Through this viewpoint, the immune system is responsible for isolating the implant biomaterial foreign body by forming bone around the oral implant effectively shielding off the implant from the host bone system, i.e. osseointegration becomes a continuous and dynamic host defense reaction. At the same time, this has led to the proposal of a new model of osseointegration, the foreign body equilibrium (FBE). In addition, as an oral wound, the soft tissues are involved with all their innate immune characteristics. When implant integration is viewed as an osteoimmune reaction, this has implications for how marginal bone is regulated. For example, while bacteria are constitutive components of the soft tissue sulcus, if the inflammatory front and immune reaction is at some distance from the marginal bone, an equilibrium is established. If however, this inflammation approaches the marginal bone, an immune osteoclastic reaction occurs and marginal bone is removed. A number of clinical scenarios can be envisioned whereby the osteoimmune equilibrium is disturbed and marginal bone loss occurs, such as complications of aseptic nature and the synergistic activation of pro-inflammatory pathways (implant/wear debris, DAMPs, and PAMPs). Understanding that an implant is a foreign body and that the host reacts osteoimmunologically to shield off the implant allows for a distinction to be drawn between osteoimmunological conditions and peri-implant bone loss. This review will examine dental implant placement as an osteoimmune reaction and its implications for marginal bone loss.

[Myxoid liposarcoma of the retroperitoneum. Presentation of a clinical case]. / Liposarcoma mixoide del retroperitoneo. Presentazione di un caso clinico.

Of all the soft tissue sarcomas, those localised in the retroperitoneum represent a particular challenge to the surgeon. Diagnosis is often late, when the tumour has already reached considerable proportions, creating particular problems for its removal. Liposarcomas are the most common histological form of retroperitoneal tumour. The authors report the case of a patient with retroperitoneal myxoid liposarcoma and use their analysis as the starting point for a review of the literature focused on the diagnosis and treatment of retroperitoneal tumours. They underline that modern imaging techniques (Eco, CT, NMR) are essential during the preoperative stage for a complete and detailed study of the neoplasm, as well as during follow-up. With regard to treatment, surgery is still the most effective approach in cases where this is feasible. The current trend towards aggressive surgery is backed by the improved results in terms of survival. An improved prognosis for patients with retroperitoneal tumours is linked to an early diagnosis and the development of more efficacious complementary therapies.

In vitro dentin pretreatment: surface roughness and adhesive shear bond strength.

The aim was to define the morphology and roughness of dentin from different tooth areas after various pretreatments to identify the effect of hybrid layer, resin tags, and mineralised dentin surface on shear bond strength. Thirty-eight extracted molars were used, each providing two sections of cervical (c) and lateral (l) dentin. Five pretreatments were performed: A) 0.2% EDTA; B) abrasion with Al2O3 particles, 0.2% EDTA; C) 10% H3PO4; D) 10% H3PO4 and immersion in a collagenase solution; E) control: no treatment. Z100 composite resin cylinders were bonded to the specimens with All Bond 2 bonding resin and tested for shear bond strength. Twelve other specimens from each group were analysed with an optical profilometer and an atomic force microscope, and four were further examined by scanning electron microscopy (SEM). Mean shear strength values in MPa were: Ac: 8.36 +/- 4.23; Al: 8.77 +/- 3.68; Bc: 6.05 +/- 3.62; Bl: 8.39 +/- 4.60; Cc: 6.87 +/- 3.45; Cl: 9.00 +/- 5.62; Dc: 13.30 +/- 5.45; Dl: 8.44 +/- 4.47; Ec: 4.10 +/- 1.54; El: 6.09 +/- 4.34. No statistically significant difference for cervical versus lateral dentin was found within treatments except for group D. Treatments performed on lateral dentin did not differ significantly. In cervical dentin, A differed from E; C from E; and D from A, B, C and E. An increased surface roughness was found in group D. Shear bond strength to dentin did not seem to depend on a hybrid layer formation, but on the direct contact of the adhesive with the mineralised dentinal surface and partly on the orientation of the dentinal tubules.

[Hepatic incidentaloma. A case report of cholangiocarcinoma]. / Incidentaloma epatico. Osservazione di un caso di colangiocarcinoma.

The finding of incidentalomas is becoming increasingly frequent during the course of routine diagnostic tests. At the hepatic level, the preclinical diagnosis of primary tumours has enabled a growing number of patients to undergo surgery with reduced operating trauma and greater oncological radicality. The authors report a case of cholangiocarcinoma whose pre-clinical diagnosis enabled its resection in spite of the patient's advanced age.

[Mucinous cystadenocarcinoma (malignant mucocele) of the cecal appendix]. / Cistoadenocarcinoma mucinoso (mucocele maligno) dell'appendice cecale.

Mucinous cystadenocarcinoma of the cecal appendix is a very rare malignant neoplasia. The majority of these tumours are discovered during surgery performed for other pathologies or as a chance finding in the histological analysis of surgically removed inflamed appendix. There is no characteristic symptomatology of this neoplasia which requires oncologically correct surgery, such as right hemicolectomy. The authors report a case study o peritoneal recidivation of a mucinous cystadenocarcinoma of the appendix.

[Primary gastric lymphoma. Survey of 5-years surgical cases]. / Linfomi gastrici primitivi. Revisione di 5 anni di casistica operatoria.

The incidence of gastric lymphoma, unlike that of carcinoma, is increased in these last years. In spite of all that, until today, there isn't codified therapeutic trend. There are many reasons: different patterns of histological classification, the importance of the different adjuvant therapies. Personal experience in ten case of primitive gastric lymphoma over a total of 63 operations of gastric neoplasms in five years (1989-1993) is presented. The analysis of personal results and a review of the literature suggest guideline (surgery, chemotherapy) according to the study of the disease, underlining that in every case the most important therapeutic approach.

In vitro marginal leakage around Class II resin composite restorations with glass-ceramic inserts.

The aim of the study was to evaluate in vitro the marginal seal in Class II resin composite restorations reinforced with glass-ceramic inserts. Forty Class II cavities, with the gingival margins located at the cementoenamel junction, were restored with Palfique Estelite light-cured resin composite and one of two different bonding agents, All Bond 2 and Tokuso Light Bond, with or without the inclusion of glass-ceramic inserts. The extent of dye penetration along the tooth-restoration interface was measured under an optical microscope. The marginal seal of composite restorations placed with All Bond 2 was significantly better than that of restorations placed with Tokuso Light Bond. There was significantly less microleakage in All Bond 2 restorations without glass-ceramic inserts than in All Bond 2 restorations containing glass-ceramic inserts. No significant difference in marginal seal was demonstrated between Tokuso Light Bond restorations with glass-ceramic inserts and those without inserts.

[Short term assessment of anthropometric indices and metabolic parameters in obese subjects treated with acarbose]. / Valutazione (a breve termine) del comportamento degli indici antropometrici e dei parametri bioumorali in soggetti obesi trattati con acarbosio.

Acarbose represents the first of a new class of oral antidiabetic drugs: the alpha-glucosidases inhibitors. This drug in fact delays the production of monosacchtarides inhibiting the alpha-glucosidases of the small bowel, that are responsible of digestion of complex polysaccharides and sucrose. In patients with insulin dependent diabetes mellitus (IDDM) acarbose, significantly reduces the postprandial blood glucose levels, and improves the symptoms associated with nocturnal hypoglycaemia reducing the daily insulin dosage. Furthermore acarbose ameliorates the glycemic control of obese patients when associated with hypocaloric diet. The aim of our study has been to value the effectiveness of acarbose 300 mg/day for 12 weeks in patients affected by moderate obesity (30 < - BMI < 40) and with impaired glucose tolerance (IGT). We have studied 12 patients, 6 have been treated with acarbose and hypocaloric diet, while the other 6 have been treated only with diet, these last formed the control group. Before and after the treatment, anthropometric indexes and haematologic parameters have been observed. Patients treated with acarbose presented a significative decrement of body weight, BMI, fat free mass, fat mass and of basal and peak glycaemic values after oral glucose tolerance test (OGTT). Serum lipid values, insulin levels during OGTT and blood pressure presented a not significative improvement. Gastrointestinal symptoms such as flatulence and borborygmus have been reported only in the patients treated with acarbose. The incidence of these reactions usually decreases with time.

Contraction gaps in Class II restorations with self-cured and light-cured resin composites.

PURPOSE: To evaluate in vitro the cervical gap formation in composite restorations in which an increment of autopolymerizing composite was interposed between the light-cured filling material and the dentin bonding system. Two different self-cured materials and two different adhesives were used and compared. MATERIALS AND METHODS: In 40 Class II cavity preparations with the gingival margins in dentin or cementum, an increment of either of two different autopolymerizing composites, Palfique or Bisfil 2B, was interposed between the light-cured filling material (Palfique Estelite) and either of two different dentin bonding systems, All-Bond and Superbond D (20 restorations each). The specimens were immersed in toluidine blue dye. A section was taken from each specimen and examined under an optical microscope. The extent of dye penetration was measured. The specimens were then stored in water for 1-4 months and replicas of the sections were examined by SEM. RESULTS: Good marginal adaptation was observed for All-Bond/Bisfil 2B in all the restorations. All-Bond/Palfique showed good adaptation in 7 out of 10 cases, the failures occurring between bonding agent and composite. Superbond D/Palfique and Superbond D/Bisfil 2B showed marginal gap formation in 8 out of 10 and in all the restorations respectively. In the latter, four gaps occurred between bonding agent and dentin. As a consequence, a very significant difference (P<0.001) was found between All-Bond and Superbond treatments; no significant difference was found between Bisfil 2B and Palfique in each group treated with either All-Bond or Superbond. After 1-4 months storage in water, hygroscopic expansion of the restorative materials reduced the total number of gaps and the efficacy of the treatments was no more significantly different.

Microleakage in Class 2 composite resin restorations.

Using the dye penetration method, the effect on the microleakage of class 2 resin restorations of two dentin bonding systems that use 10% citric acid-containing dentin conditions was studied. These results were then compared to the results obtained when the manufacturer's conditioner was replaced by a mild surface-active detergent containing 0.2% EDTA and 1% NaF. The cavities that were treated with the 0.2% EDTA-containing conditioner in place of the manufacturer's conditioner showed similar results: Neither of the two bonding systems could totally prevent cervical gap formation.

The marginal adaptation of four different bonding agents in Class II composite resin restorations applied in bulk or in two increments.

Class II cavities with two retention grooves at the cervical wall, situated at the cemento-enamel junction, were restored with Palfique Light Cured composite resin and one of four different bonding agents and one of two composite resin application techniques. In 80 restorations, any gap present was disclosed by the penetration of a fluorescent resin into the air-filled gap. In another 80 restorations a toluidine blue solution was used to reveal gaps. Tokuso Light Bond and Superbond C&B had poor marginal adaptation: gap formation was observed in 90.0% and 57.5% of those restorations, respectively. In contrast, All-Bond had a 20.0% rate and Superbond D-liner had a 12.5% rate of restorations with failures, represented by very thin gaps in the outer part of the cervical wall. Bulk application of the composite resin material and light curing from the cervical and axial walls through a plastic matrix strip gave results comparable to those of a two-stage horizontal application technique with light curing from the occlusal area and a metal matrix band.

The influence of lining techniques on the marginal seal of Class II composite resin restorations.

Various sealing techniques using a light-curing dental adhesive (Scotchbond 2) and bulk application of a light-curing resin-bonded ceramic were examined in 203 Class II cavities. Different pretreatment procedures and lining materials were used, and in one series resin impregnation of the contraction gap was included. The presence of gaps or leakage was disclosed either by a dye or a fluorescent resin penetration technique. In many restorations, Scotchbond 2 and a light-curing glass-ionomer lining did not prevent gap formation at the cervical wall. The gap usually occurred between the liner and the dentin, with dye penetration into the dentin. Three liners, one containing polytrifluorethylene sodium fluoride and calcium fluoride, one containing polyamide resin, and one containing calcium hydroxide, did not prevent dye penetration to the dentin at all; good dentinal protection was frequently observed, however, in cavities treated with a hydrophilic shellac film prior to placement of a polystyrene liner. The best results were observed when dentinal treatment with this lining system was followed by resin impregnation of the contraction gap after the composite resin had set.

The effect of cervical grooves on the contraction gap in class 2 composites.

The extent and the width of the cervical contraction gap in class 2 composite resin restorations were examined using a fluorescent resin-penetrating technique. In all restorations Scotchbond 2 bonding system and P-50 were used. The cervical wall was prepared either with no groove or with one or two grooves. The results indicated that the extent of the contraction gap was reduced when two retention grooves were prepared. The difference between no groove and two grooves was statistically significant. The width of the gap was also reduced, but not with statistical significance. A statistical difference was also found when one retention groove was compared with no groove.

Effect of tooth storage and cavity cleansing on cervical gap formation in Class II glass-ionomer/composite restorations.

Class II cavities with the cervical margin just below the C-E junction and with two cervical retention grooves were prepared in intact human premolars, 31 cavities in teeth stored frozen and 29 cavities in teeth stored in 1% chloramine solution. The teeth from both storage conditions were assigned to two groups; in one group, the cavities were cleaned with a water spray, in the other group, with a cleaner containing 0.2% EDTA and 1% NaF. All cavities were lined with Vitrebond and restored with P50. Cervical contraction gaps were disclosed by a fluorescent resin penetration technique. The length and width of each gap were analysed. A contraction gap was revealed in 17 of the 31 cavities in teeth stored frozen (54.8%) and in 22 of the 29 restorations in the teeth stored in chloramine (75.8%). The width of the gap was significantly greater in teeth stored in chloramine (p = 0.0004). No statistical difference in gap formation was found between cavities cleaned with water or with the detergent containing 0.2% EDTA and sodium fluoride. Since the cavity cleansing procedure was not a significant factor in gap formation, apparently removing the superficial smear layer with the cavity cleaner does not impair the bonding of Vitrebond to the dentin. However, gap formation appeared to be significantly affected by the storage conditions of the extracted teeth. It is suggested that teeth to be used in bond strength and leakage experiments should be stored frozen rather than stored in 1% chloramine solution.