Use of fractal analysis in dental images for osteoporosis detection: a systematic review and meta-analysis

Fractal dimension (FD) calculated on oral radiographs has been proposed as a useful tool to screen for osteoporosis. This systematic review and meta-analysis firstly aimed at assessing the reliability of FD measures in distinguishing osteoporotic patients (OP) from healthy controls (HC), and secondly, to identify a standardized procedure of FD calculation in dental radiographs for the possible use as a surrogate measure of osteoporosis. A comprehensive search was conducted up to September 2020 using PubMed, Web of Science, and SCOPUS databases. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Meta-analysis was performed on FD values calculated for HC and OP. Overall, 293 articles were identified. After a three steps screening, 19 studies were included in the qualitative appraisal and 12 were considered for meta-analysis. The methodological quality of the retrieved studies was generally low. Most of the studies included used White and Rudolph and box counting to process the images and to calculate FD, respectively. Overall, 51% of the studies found a meaningful difference between HC and OP groups. Meta-analyses showed that to date, FD measures on dental radiographs are not able to distinguish the OP from HC group significantly. From the current evidence, the use of FD for the identification of OP is not reliable, and no clear conclusion can be drawn due to the heterogeneity of studies. The present review revealed the need for further studies and provided the fundamentals to design them in order to find a standardized procedure for FD calculation (regions for FD assessment; images processing technique; methods for FD measurement). More effort should be made to identify osteoporosis using dental images which are cheap and routinely taken during periodic dental examinations.

Response of periodontium to mineral trioxide aggregate and Biodentine: a pilot histological study on humans

BACKGROUND

The aim of this study was to investigate for the first time the histological response of human periodontium to mineral trioxide aggregate (MTA) and Biodentine.

METHODS

Six patients scheduled for implant full-arch rehabilitation were randomly assigned to one of the two test groups: MTA or Biodentine treatment. For each patient, two teeth scheduled for strategic extraction were randomly assigned either to the test or to the control treatment. A lateral perforation was drilled on the root and either repaired with MTA/Biodentine or filled with gutta-percha(control). Three months later, the teeth were extracted along with the coronal third of the alveolar bone and a portion of gingival tissue, while performing implant placement, and processed for histological analysis.

RESULTS

Biodentine resulted in less extrusion into the periodontal environment. All the materials showed good biocompatibility. A new mineralized cementum-like tissue incorporating periodontal fibres was visible in all cases treated with MTA. A small amount of new mineralized tissue was found in two Biodentine cases but not in control cases. Biodentine resulted in less damage to the periodontal ligament.

CONCLUSIONS

Bioactivity and biocompatibility of MTA were confirmed in human models. Biodentine proved to be biocompatible, but it seems not to induce cementum regeneration.

Factors Associated with Apoptosis in Symptomatic and Asymptomatic Carotid Atherosclerotic Plaques

The aim of this study was to investigate the differences that are present between apoptosis in symptomatic (with symptoms of cerebral ischemic attack) and asymptomatic carotid atherosclerotic plaques. The apoptotic process in macrophages and smooth muscle cells was evaluated. Cellular markers and products of immune cells in symptomatic and asymptomatic atherosclerotic plaque and endoarterectomy specimen were analyzed by immunohistochemistry. No statistically significant differences were present regarding the mean SMC actin-positive area. Using double staining of α-smooth muscle actin and TUNEL techniques, the number of smooth muscle cells in apoptosis was statistically higher in symptomatic plaque as compared with asymptomatic plaque. Statistically significant differences (p=0.009) were also found in the CD45-positive cells in the inflammatory infiltrate. The CD68-positive macrophages showed statistically significant differences (p=0.0001). Similarly, the double staining with CD68 and TUNEL revealed that apoptotic macrophages were mainly present in asymptomatic plaques rather than symptomatic plaques. Statistically significant differences (p<0.001) were found in the Bcl-2 expression, with higher values in asymptomatic plaques. Our data showed that the increase of the inflammatory cells contributes to plaque instability and that death due to apoptosis of smooth muscle cells in symptomatic plaques could contribute to their destabilization and explains their tendency to fracture.

Vascular Endothelial Growth Factor Expression (VEGF) in Salivary Glands of Young and Old Hyperoxic Rats

The aim of this study is to evaluate whether hyperoxia and age can influence the expression of vascular endothelial growth factor (VEGF) in the salivary glands of rats. Our study was carried out on four groups of male Wistar rats (total 24 rats). One group was composed of 6 young rats (3 months old); another group by 6 old rats (24 months old). The rats belonging to the first two groups were exposed to hyperoxia (98–100% O2) for a period of 60–65 hours in a large Plexiglas chamber; the other two groups were control groups. The rats were then anaesthetized with Nembutal (30 mg/kg) intraperitoneally and then killed. The submandibular glands were removed and processed for immunohistochemical analysis of VEGF. The exposure to hyperoxia decreased salivary gland VEGF expression in rats. The tissues analyzed (nervous tissue, vascular endothelium, myoepithelial cells, ductal endothelium, mucinous glands) always expressed VEGF, thus demonstrating that not only vascular endothelial cells, but also the other elements evaluated, have a role in the neoangiogenesis. Only in the serous glands, in both normoxic and hyperoxic young and old rats, was the VEGF expression constantly negative and it did not influence the neoangiogenesis. The vascular growth is a fundamental part of normal salivary gland development, so we speculated that strategies aimed at preservation or promotion of salivary gland VEGF expression may mitigate or attenuate hyperoxia-induced gland microvascular injury. Further studies specifically aimed at investigating these prospects are warranted.

Micro-topography and reactivity of implant surfaces: an in vitro study in simulated body fluid (SBF)

The creation of micro-textured dental implant surfaces possessing a stimulating activity represents a challenge in implant dentistry; particularly, the formation of a thin, biologically active, calcium-phosphate layer on their surface could help to strengthen the bond to the surrounding bone. The aim of the present study was to characterize in terms of macrostructure, micro-topography and reactivity in simulated body fluid (SBF), the surface of titanium (Ti) implants blasted with TiO2 particles, acid etched with hydrofluoric acid, and activated with Ca and Mg-containing nanoparticles. Sandblasted and acid-etched implants were analyzed by ESEM-EDX (environmental scanning electron microscope with energy dispersive X-ray system) to study the micromorphology of the surface and to perform elemental X-ray microanalysis (microchemical analyses) and element mapping. ESEM-EDX analyses were performed at time 0 and after a 28-day soaking period in SBF Hank's balanced salt solution (HBSS) following ISO 23317 (implants for surgery—in vitro evaluation for apatite-forming ability of implant materials). Microchemical analyses (weight % and atomic %) and element mapping were carried out to evaluate the relative element content, element distribution, and calcium/phosphorus (Ca/P) atomic ratio. Raman spectroscopy was used to assess the possible presence of impurities due to manufacturing and to investigate the phases formed upon HBSS soaking. Micro-morphological analyses showed a micro-textured, highly rough surface with microgrooves. Microchemical analyses showed compositional differences among the apical, middle, and distal thirds. The micro-Raman analyses of the as-received implant showed the presence of amorphous Ti oxide and traces of anatase, calcite, and a carbonaceous material derived from the decomposition of an organic component of lipidic nature (presumably used as lubricant). A uniform layer of Ca-poor calcium phosphates (CaPs) (Ca/P ratio <1.47) was observed after soaking in HBSS; the detection of the 961 cm⁻¹ Raman band confirms this finding. These implants showed a micro-textured surface supporting the formation of CaPs when immersed in SBF. These properties may likely favor bone anchorage and healing by stimulation of mineralizing cells.

Immunoexpression of angiogenesis and proliferation markers in patients treated with cyclosporin A

AIM

In the present immunohistochemical study, the expression of vascular endothelial growth factor, nitric oxide synthase 1 and 3, and Ki-67 in the gingival tissues of renal transplant patients treated with cyclosporin A was assessed. Gingival overgrowth (GO) frequently occurs in transplant patients receiving immunosuppressive drugs such as cyclosporine and this gingival inflammation might play an important role in the pathogenesis of drug-induced GO.

METHODS

Twenty-eight human gingival biopsies were taken from healthy patients with chronic periodontitis (N.=14 control group), and from renal transplant recipients treated with cyclosporin A (N.=14 test group). The retrieved specimens were immunohistochemically processed and stained for vascular endothelial growth factor, nitric oxide synthase 1 and 3, and Ki-67.

RESULTS

The levels of vascular endothelial growth factor, nitric oxide synthase 1 and 3, and Ki-67 were found to be significantly different among groups (P>0.001), with patients treated with cyclosporin A showing higher levels of all the analyzed markers compared to control group.

CONCLUSION

In summary, the data from this pilot study suggests that the investigated factors have a role in the inflammation processes associated to immunosuppressive therapy. However, further studies with a larger sample population need to be conducted for an exhaustive knowledge of the mechanisms leading to GO.

Bucco-Lingual Crestal Bone Changes Around Implants Immediately Placed in Fresh Extraction Sockets in Association or not With Porcine Bone: A Non-Blinded Randomized Controlled Trial in Humans

Background: The aim of the present randomized controlled clinical trial was to assess the bucco-lingual bone changes of implants immediately placed in fresh extraction sockets in association or not with porcine bone. Methods: Forty patients were included in the present study, and were randomly assigned to the control (n = 20) and test (n = 20) groups. Each patient received a single implant placed into an immediate extraction site of a molar or a first upper premolar with a flapless approach. In the control sites no grafting material was placed, while in the tests a deantigenated collagenated bone substitute of porcine origin was used to fill the gaps between the implant and the extraction socket. The bucco-lingual bone width was measured at different time points: at the time of surgery (T0), at 90 days (T1), at 110 days (T2) and after 6 months of masticatory function (T3). The values were statistically analyzed between and within the treatment groups (p>0.05). Results: All the implants were osseointegrated. Four control implants were excluded from the analysis due to the exposure of the coronal portion of the fixture. At T1, T2 and T3, statistically significant differences were found by comparing the mean width of the bucco-lingual bone between control and test groups. The mean values decreased during the observation period in both groups; statistically significant differences within controls were detected at T1, T2 and T3, and at T2 and T3 within tests. Conclusions: The outcomes of present study suggested that porcine bone enabled to avoid bucco-lingual crestal bone changes in implants immediately placed in fresh extraction sockets.

Management of compound odontoma in a 10-year-old girl preserving the associated impacted permanent tooth

AIM

Compound odontoma has been reported to be the most common of all odontogenic neoplasms and tumor- like lesions. Only rarely the treatment of this lesion in association with an impacted tooth has been reported.

CASE REPORT

A compound odontoma in a 10-year-old girl, associated with an impacted permanent incisor is described, focusing on the diagnosis and the importance of early treatment of this lesion. The patient underwent surgical excision of the lesion and it was decided to wait for the spontaneous eruption of the impacted tooth. After 6 months no eruption was observed and thus the orthodontic treatment was deemed necessary. At the one-year follow-up, the tooth was brought into the maxillary arch.

Patients with Peri-Implantitis, unlike Those with a Healthy Peri-Implant Microenvironment, Display Antibodies to More Than One Heat Shock Protein (HSP 27, HSP 65 and HSP 90) Linear Epitope

The success of a dental implant treatment requires hard and soft tissue integration and osseointegration, mechanisms that entail a direct anchorage of the implant in the bone without interposition of soft tissue. Peri-implantitis is defined as an inflammatory reaction of the tissues surrounding a functioning dental implant. During inflammation, a high incidence of autoantibodies has been reported. The hypothesis of the present study is that the occurrence of autoantibodies to self-antigens including extracellular matrix (ECM) molecules and heat shock proteins (HSPs) might affect the dental implant outcome. Therefore, we evaluated the occurrence of antibodies to ECM molecules (Collagen (C) I, III, IV, V, fibronectin, laminin) and HSPs (HSP 27, HSP 65, HSP 90) in subjects with a healthy peri-implant microenvironment (n=29) as compared to patients with peri-implantitis (n=13). We also evaluated the HSP 27 expression in gingival fibroblasts grown in an inflammatory microenvironment. Antibodies to conformational ECM epitopes of CI, CIII and laminin were observed both in subjects with healthy peri-implant conditions and peri-implantitis. Antibodies to more than one HSP linear epitope were found in patients with peri-implantitis but not with healthy peri-implant conditions (p=0.024). Gingival fibroblasts grown in an inflammatory microenvironment showed increased HSP 27 cytoplasmic and plasma membrane expression as compared to fibroblasts grown in normal conditions. Immunity to multiple linear HSPs epitopes in patients with peri-implantitis and not in patients with a healthy peri-implant microenvironment might be relevant for monitoring the implant outcome and help to understand the role of subsets of autoantibodies in implant osseointegration.

Wear of dental sealing materials using the replication technique

AIM

The aim of the present study was an in vivo evaluation of the wear of different sealing materials using the replication technique.

MATERIALS AND METHODS

Four different sealing materials were randomly applied on 2 out of 4 caries-free permanent first molars of each patient. Impressions were taken at T0: before the sealing material was applied; T1: right after the application; T2: 6 months after the application, and T3: 1 year after the application. The impressions were then processed for scanning electron microscopy analysis of the wear of the examined materials. Statistical analysis was used to evaluate differences among and within the 4 groups.

RESULTS

At T2, the average ratio of residual material in all the groups was 62.37% ± 1.21%, while at T3 it was 49.63% ± 1.11%. At both T2 and T3 there were no statistically significant differences among the 4 groups examined (p=0.76 and p=0.50 respectively). Comparison within the same group at T2 and T3 showed that statistically significant differences were only detected in group D (p=0.015).

CONCLUSION

Sealing materials do not undergo a complete loss after 1 year of application, thus indicating that they are suitable for caries prevention.

VEGF and MVD expression in sinus augmentation with autologous bone and several graft materials

OBJECTIVE

The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential.

METHODS

Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer (n = 5 patients) and control group--autogenous bone only (n = 13 patients).

RESULTS

In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA (P < 0.001) and CP in relation to control (P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups (P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP (P < 0.001).

CONCLUSION

Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized.

Vascular endothelial growth factor expression (VEGF) in salivary glands of diabetic rats

This study is aimed at evaluating vascular endothelial growth factor (VEGF) expression in the salivary glands of diabetic rats. Our study was carried out on 1 group of male Wistar rats and 1 group of male Bio Breeding Wistar (BB/W) pre-diabetic rats. The first group (control) was composed of 11 rats (4 months old), and the other (test) of 11 rats (4 months old) which showed diabetes at day 85 of life. This kind of diabetes can be compared to human diabetes mellitus type 1. The submandibular glands were removed and processed for immunohistochemical analysis of VEGF. Diabetes increased salivary gland VEGF expression in the rats. The tissues analyzed (vascular endothelium, ductal endothelium, mucinous glands) always expressed VEGF, thus demonstrating that not only vascular endothelial cells, but also the other elements evaluated, have a role in the neoangiogenesis process. In both control and diabetic rats, the VEGF expression was constantly negative only in serous acini; thus demonstrating that serous acini are not involved in the neoangiogenetic processes. The vascular growth is a fundamental part of normal salivary gland development, therefore we speculate that strategies aimed at preservation or promotion of salivary gland VEGF expression may mitigate or attenuate diabetic-induced gland microvascular injury.

Microvessel density and vascular endothelial growth factor expression in sinus augmentation using Bio-Oss

AIM

The aim of this study was to evaluate microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in sinus augmentation with Bio-Oss.

METHODS

Twenty patients participated in this study. The sinuses were filled with 100% Bio-Oss. Implants were inserted after 3 months in group A, and 6 months in group B. A trephine was used to harvest bone cores. As control, the pre-existing subantral bone was used.

RESULTS

The mean MVD in control bone was 23.6 +/- 1.8. In the sites augmented with Bio-Oss, at 3 months, the MVD was 23.3 +/- 2.1, while in the sites retrieved at 6 months the MVD was 29.5 +/- 2.4. The difference in MVD between the control bone and group A was not statistically significant. The difference between the control bone and group B was statistically significant (P < 0.05). The statistical analysis showed that the difference in MVD between group A and group B was statistically significant (P < 0.05).

CONCLUSIONS

Bio-Oss seemed to induce an increase in MVD that reached a higher value after 6 months. The percentage of vessels positive to VEGF was higher in group A than in group B. Our data also showed a higher percentage of vessel and stromal cells positive to VEGF and higher MVD values in areas where there was newly formed bone compared with areas where maturation processes were occuring, and this fact could point to a close spatial relationship between angiogenesis and osteogenesis.

Effects of Emdogain on osteoblast gene expression

OBJECTIVE

Emdogain (EMD) is a protein extract purified from porcine enamel and has been introduced in clinical practice to obtain periodontal regeneration. EMD is composed mainly of amelogenins (90%), while the remaining 10% is composed of non-amelogenin enamel matrix proteins such as enamelins, tuftelin, amelin and ameloblastin. Enamel matrix proteins seem to be involved in root formation. EMD has been reported to promote proliferation, migration, adhesion and differentiation of cells associated with healing periodontal tissues in vivo.

DESIGN

How this protein acts on osteoblasts is poorly understood. We therefore attempted to address this question by using a microarray technique to identify genes that are differently regulated in osteoblasts exposed to enamel matrix proteins.

RESULTS

By using DNA microarrays containing 20,000 genes, we identified several upregulated and downregulated genes in the osteoblast-like cell line (MG-63) cultured with enamel matrix proteins (Emd). The differentially expressed genes cover a broad range of functional activities: (i) signaling transduction, (ii) transcription, (iii) translation, (iv) cell cycle regulation, proliferation and apoptosis, (v) immune system, (vi) vesicular transport and lysosome activity, and (vii) cytoskeleton, cell adhesion and extracellular matrix production.

CONCLUSIONS

The data reported are the first genome-wide scan of the effect of enamel matrix proteins on osteoblast-like cells. These results can contribute to our understanding of the molecular mechanisms of bone regeneration and as a model for comparing other materials with similar clinical effects.

Pleomorphic lipoma of the oral cavity. Report of a case

Pleomorphic lipoma (PL) is a rare benign tumor mainly located in the upper back, upper shoulders, and back of the neck in elderly men. More rarely it is located in the head and neck region and in the oral cavity. The differential diagnosis should be made with sclerosing liposarcoma and well-differentiated liposarcoma. A 59-year-old male patient was referred for the presence of a lesion involving the marginal and adherent gingiva of teeth # 5; this lesion extended into the vestibular mucosa. The lesion had a 2 cm diameter, showed no tenderness, had a hard-parenchymatous consistency, was mobile on the underlying tissues and was covered by normal appearing mucosa. Under local anesthesia, the lesion was completely removed. A free gingival graft from the palate was used to cover the defect. Microscopically, it was possible to observe mature adipocytes, spindle cells and rare ''floret-like'' cells. Lipoblasts and mitoses were absent. The definitive pathologic diagnosis was pleomorphic lipoma. No recurrences were present after a 5 years follow-up. Local excision is adequate for PL and the tumor does not recur.

CD10 expression in stromal cells of oral cavity squamous cell carcinoma: a clinic and pathologic correlation

OBJECTIVE

CD10 is expressed on the majority of follicle-center lymphomas and Burkitt lymphomas. CD10 has also been shown to be present in a variety of other neoplasms.

DESIGN

The aim of this study was a correlation of CD10 and several parameters: age, tumor size, presence of lymph node metastases, clinic stage, histologic grading, presence of local recurrences.

MATERIALS AND METHODS

The tissues of 77 consecutive patients with oral cavity squamous cell carcinoma were evaluated using immunostaining with monoclonal antibody for CD10.

MAIN OUTCOME MEASURES

Highly significant correlations were found with the lymph node status, the presence of local recurrences and the histologic grading. The presence of CD10-positive cells was not correlated with the age of patients, tumor size and clinic stage.

RESULTS

The results of the present study show that in oral squamous cell carcinoma CD10 positivity is an indicator of worse prognosis. Another strong correlation was found with the presence of local recurrences. Also the histologic grade was significantly correlated with the CD10 positivity.

CONCLUSION

Our results point to the fact that CD10 expression can, perhaps, have an important role in tumor invasion, probably facilitating the occurrence of metastases.

[Rare manifestation of nasal polyposis in the Peutz-Jeghers syndrome]

We are relating a case of the Peutz-Jeghers syndrome, a disease characterized by hamartomatous polyposis and by mucocutaneous melanic pigmentation, in a rare variant identified by the presence of nasal polyposis. At the objective E.N.T. examination, the patient's nasal fossae were completely obstructed by translucid masses of a polypoid appearance and, moreover, a melanic pigmentation of the cutis, of the perilabial mucosa and of the oral cavity was encountered. At the X-ray examination and, later, during the operation, also the right maxillary sinus appeared completely obstructed by polypoid masses. At the histologic examination, such polypoid neoformations were quite similar to common polyps of an inflammatory nature and, so, absolutely without any peculiar structural features. The nasal polyposis in patients suffering from the Peutz-Jeghers syndrome has been mentioned by Peutz since his first observation but it has been seldom described in the subsequent publications, even in relation to the presentation of rare causes to Congresses and Magazines of an exclusively gastroenterological interest, in which the main concern was that of identifying both the clinical and histological aspects of gastrointestinal hamartomatous polyposis and the correlation between the syndrome and the formation of malignant neoplasias in other organs to the prejudice of the secondary manifestations of the disease. Nevertheless, the nasal polyposis and, at any rate, the tendency to the formation of polyps in other districts (urinary tract, bronchi) are described among the less important features also in gastroenterological treatises of most recent publication. Clinical observations, even occasional, are completely missing in the E.N.T. ambit.(ABSTRACT TRUNCATED AT 250 WORDS)