Heritability of myopic refractive errors in identical and fraternal twins

The existence of a visual feedback control of eye growth in humans is controversal, as the contributions of genetic and environmental factors are still unknown. To evaluate the heritability of refractive defects, we measured ocular refraction in 19 monozygote and 20 dizygote twin pairs (mean age 5 years). Monozygosity was ascertained by a common chorion, similarity of somatic traits, and identical dermatogliphes and was confirmed in myopes by blood marker diagnosis. Ocular refractive defects and axial length were evaluated by eye-loplegic autorefractometry and biometry. By comparing identical and fraternal twins heritability of refractive defects was estimated to be 0.08–0.14; this low value indicates that the observed variability in refractive errors is nongenetic in origin. Three monozygote pairs were anisomyopic; differences between eyes in identical twins were related to the increased axial length of myopic eyes. In one eye, myopia was attributed to visual deprivation induced by a congenital cataract, while in five eyes it was correlated directly to the degree of astigmatic defects. The discordant axial length observed in monozygote twins is nongenetic. In agreement with previous findings reported in the literature, it is proposed that visual impoverishment of retinal images may play an early regulatory role in postnatal eye growth.Deceased     

Immunoreactivity for interleukin 1-beta and tumor necrosis factor-alpha and ultrastructural features of monocytes/macrophages in periapical granulomas.

Interleukin 1 (IL-1) and tumor necrosis factor (TNF) have recently been shown to be involved in bone resorption, and because macrophages constitute a significant part of human periapical granulomas, it is reasonable to suspect that they may secrete IL-1 and TNF. The purpose of our investigation was to detect and characterize IL-1 beta- and TNF-alpha-producing cells in human periapical granulomas. Fresh tissue samples obtained during surgery from 10 patients with previously untreated teeth and histologically established periapical granulomas were studied with light and electron microscopy and with immunohistochemical analysis with monoclonal antibodies against IL-1 beta and TNF-alpha. There were very few IL-1 beta + and TNF-alpha + cells present in periapical granulomas, and the positive cells had monocyte/macrophage morphology. The IL-1 beta + cells were located mainly in areas of active exudation and were surrounded by and/or were in close contact with lymphoid cells, whereas TNF-alpha + cells were scattered and in contact with or near other inflammatory cells at the periphery of active granulation tissue. This suggests that the IL-1 beta + cells may act in a paracrine manner to activate lymphoid cells. The ultrastructural findings showed that only some macrophages are adapted to extracellular secretion rather than phagocytosis. These modified macrophages could be the major producers of interleukins in tissues. Occasionally, they have plasmacytic or plasmacytoid features resembling the so-called "plasmacytoid monocytes". Only a minor fraction of the monocytes/macrophages (representing about 40% of the inflammatory cells) is in an active cytokine-producing state.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immunohistochemical analysis of a dentinogenic ghost cell tumour

A dentinogenic ghost cell tumour in an 80-year-old male patient is presented. It is an extremely rare tumour and only 10 cases have been reported in the English literature. The lesion showed odontogenic epithelium, ghost cells, dentinoid, giant cells. The immunohistochemical analysis for Mib-1 and bcl-2 showed a strong positivity of the cells of the odontogenic epithelium, while with p53 only a rare positivity was observed. Completely negative were the ghost cells, giant cells and dentinoid material. In this tumour the cells expressing Mib-1 and bcl-2 could be the cells that proliferate, and that could undergo malignant transformation.     

Nuclear fractal dimension in oral squamous cell carcinoma: a novel method for the evaluation of grading,staging, and survival

Fractal dimension (FD) in tissue specimens from patients with oral squamous cell carcinoma (OSCC) was evaluated. FD values in different stages of OSCC, and the correlations with clinicopathological variables and patient survival were investigated. Histological sections from OSCC and control non‐neoplastic mucosa specimens were stained with hematoxylin–eosin for pathological analysis and with Feulgen for nuclear evaluation. FD in OSCC groups vs. controls revealed statistically significant differences (P < 0.001). In addition, a progressive increase of FD from stage I and II lesions and stage III and IV lesions was observed, with statistically significant differences (P = 0.003). Moreover, different degrees of tumor differentiation showed a significant difference in the average nuclear FD values (P = 0.001). A relationship between FD and patients' survival was also detected with lower FD values associated to longer survival time and higher FD values with shorter survival time (P = 0.034). These data showed that FD significantly increased during OSCC progression. Thus, FD could represent a novel prognostic tool for OSCC, as FD values significantly correlated with patient survival. Fractal geometry could give insights into tumor morphology and could become an useful tool for analyzing irregular tumor growth patterns.     

Multivariate analysis of the influence of peri-implant clinical parameters and local factors on radiographic bone loss in the posterior maxilla: a retrospective study on 277 dental implants

Clinical Oral Investigations - The aim of the present study was to investigate whether peri-implant clinical parameters (modified plaque index (mPI), bleeding and/or suppuration on probing (B/SOP))...     

A torque-measuring micromotor provides operator independent measurements marking four different density areas in maxillae

PURPOSE

Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them.

MATERIALS AND METHODS

A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data.

RESULTS

The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement.

CONCLUSION

The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it.     

10‐Year Follow‐Up of Immediately Loaded Implants with TiUnite Porous Anodized Surface

Background: The immediate loading of implants with a porous anodized surface is a well‐described technique. Few data are however available on the long‐term outcomes. Purpose: The aim of this prospective study was to assess the 10‐year performance of TiUnite implants supporting fixed prostheses placed with an immediate loading approach in both postextractive and healed sites. Materials and Methods: All patients received a fixed provisional restoration supported by immediately loaded parallel design, self‐tapping implants with a porous anodized TiUnite surface, and an external‐hexagonal connection. Both healed and postextractive cases were included. Success and survival rate for restorations and implants, changes in marginal peri‐implant bone level, probing depth measurements, biological or technical complications, and any other adverse event were recorded at yearly follow‐up up to 10 years after surgery. Results: A total of 210 implants fulfilled the inclusion criteria and were consecutively placed in 59 patients. Forty‐seven (22.38%) implants were lost because of the recalled patient refused to attend the planned 10‐year follow‐up. Five over 210 (2.38%) implants were lost. At the final follow‐up, the accumulated mean marginal bone loss and probing depth were, respectively, 1.93 mm (SD 0.40) and 2.54 mm (SD 0.44) for the implants placed in healed sites (n = 84); 1.98 mm (SD 0.37) and 2.63 mm (SD 0.39) for the implants placed in postextractive sites (n = 74). The restorations examined achieved a cumulative 65.26% success rate and 97.96% survival rate. The implants placed in healed and postextractive sites, respectively, achieved a 98.05% and a 96.52% cumulative survival rate. Conclusions: Positive results in terms of bone maintenance in the long‐term perspective are to be expected using immediately loaded implants with a TiUnite porous anodized surface in both postextractive and healed sites when adequate levels of oral hygiene are kept.     

Bone‐to‐Implant Contact Around Immediately Loaded Direct Laser Metal‐Forming Transitional Implants in Human Posterior Maxilla

Objective: Direct laser metal forming (DLMF) is a procedure in which a high‐power laser beam is directed onto a metal powder bed and programmed to fuse particles according to a computer‐aided design file, generating a thin metal layer. This histologic study evaluated the bone‐to‐implant contact (BIC%) around immediately loaded DLMF transitional implants retrieved after 2 months from posterior human maxillae. Methods: Twelve totally edentulous individuals (mean age, 66.14 ± 2.11 years) received DLMF transitional implants divided in twelve immediately loaded (IL) and twelve unloaded (UI) implants. These transitional implants were placed between conventional implants to support the interim complete maxillary denture during the healing period. After 8 weeks, the transitional implants and the surrounding tissue were removed and prepared for histomorphometric analysis. Results: Mature woven preexisting bone lined by newly formed bone in early stages of maturation were found around all retrieved implants. Histometric evaluation indicated that the mean BIC% was 45.20 ± 7.68% and 34.10 ± 7.85% for IL and UI, respectively (P <0.05). Conclusion: The present data obtained in humans showed that, although both IL and UI presented good BIC%, IL DLMF implants had a higher BIC% in the posterior maxilla.