Longitudinal analysis of microcirculatory parameters in gingival tissues after tooth extraction in patients with different risk profiles for wound healing disorders - a pilot study.

OBJECTIVES: We aimed to establish a risk profile for intraoral wound healing disorders based on measurements of microcirculation in gingival tissues. MATERIALS AND METHODS: Oxygen saturation (SO2) and blood flow in gingival tissues were measured with tissue spectrometry and laser doppler spectroscopy in 37 patients before/after tooth extractions. Patients were assigned to four groups: anamnestically and periodontally healthy patients (n = 7), anamnestically healthy but suffering from periodontitis (n = 10), anamnestically healthy but smoking and suffering from periodontitis (n = 10) and suffering from diabetes and periodontitis (n = 10). Measurements were performed at three different time points: Baseline measurement (T0), one day post extractionem (p.e.) (T1) and seven days p.e. (T2). RESULTS: Baseline SO2 values were higher in control patients (p = .038). This effect was most evident in comparison to smokers suffering from periodontitis (p = .042), followed by diabetics suffering from periodontitis (p = .09). An opposite trend was seen for blood flow. Patients suffering from periodontitis demonstrated higher blood flow values (p = .012). Five patients, which belonged to the group of smokers suffering from periodontitis, showed clinically a delayed wound healing. CONCLUSION: Differences in SO2 and blood flow of gingival tissue could be detected in different groups of patients with existing periodontitis compared to control patients. CLINICAL RELEVANCE: Lower baseline SO2 values could be a warning signal for possible wound healing disorders after oral surgery.

Evaluating the association between gingival crevicular blood glucose levels and finger capillary blood glucose levels according to periodontal status.

OBJECTIVES: The aim of this study was to evaluate the association between gingival crevicular blood glucose levels (GCBG) and finger capillary blood glucose levels (FCBG) according to the periodontal status of patients. MATERIALS AND METHODS: In this case-control study, 80 patients were divided into 4 groups according to their periodontal status. In these patients, an area of the maxillary gingiva with the highest probing depth was selected for blood sampling. Blood glucose obtained from this area and the right fingertip was measured with a glucometer. Data were analyzed using ANOVA and Pearson correlation coefficient with a significance threshold of 0.05. RESULTS: The groups studied were matched in regard to their sex and age (P > 0.05). The average FCBG and GCBG were not significantly different according to periodontal status (P > 0.05). The correlation between the FCBG and the GCBG showed a significant positive correlation in the total number of participants (P < 0.05, r = 0.531). CONCLUSION: The study observed a positive association between GCBG and FCBG. However, the relationship with periodontal status appeared to be relatively weak. Further research may be needed to determine the potential efficacy of GCBG in diabetes screening during periodontal examinations. CLINICAL RELEVANCE: Most patients with diabetes do not have proper periodontal health, so it may be helpful to screen for diabetes during periodontal examinations.

Assesment of radiotherapy effects on the blood flow in gingiva and dental pulp - a laser Doppler flowmetry study.

OBJECTIVE: This study aims to determine and compare the dental pulp and gingival blood flow in patients referred for oropharyngeal radiotherapy (RT) at three different time points: before the start, immediately after, and six months following the completion of RT. The aim is also to evaluate the dependence of the pulp and gingival blood flow on the radiation dose. METHODOLOGY: A prospective study included 10 patients referred for intensity-modulated RT (IMRT) in the oropharyngeal region, with at least one intact tooth surrounded by a healthy gingiva. The dose received by each selected tooth and adjacent gingiva was determined according to the map of treatment planning and computer systems. The blood flow measurements were performed using the laser Doppler flowmetry (LDF) method. RESULTS: Comparing vascular flows at three different time points, the median blood flow in the dental pulp showed no statistically significant difference (p=0.325), contrary to gingiva (p=0.011). Immediately after RT completion, the gingival flow significantly increased compared to its starting point (p=0.012). The pulp flow correlated negatively with the radiation dose, whereas a strong correlation was noted 6 months following the RT completion. CONCLUSIONS: RT caused a significant acute gingival blood flow increase, followed by a long-term (over six months) tendency to return to the starting levels. The dental pulp blood flow is differently affected by higher radiation doses (over 50Gy) in comparison to lower doses (below 50Gy). During RT planning, considering the possibility of protecting the teeth localized near the Gross Tumor Volume as a sensitive organ is recommended.

PDLSCs Regulate Angiogenesis of Periodontal Ligaments via VEGF Transferred by Exosomes in Periodontitis.

Abnormal angiogenesis is one of the significant features in periodontitis leading to progressive inflammation, but angiogenic changes of periodontal ligaments under inflammatory condition were rarely reported. Periodontal ligament stem cells (PDLSCs) were a kind of dental stem cells associated with vascularization. Here we investigated the alteration of angiogenesis of periodontal ligament in periodontitis, and revealed an exosome-mediated pathway to support the effect of PDLSCs on angiogenic improvement. Vascular specific marker CD31 and VEGFA were found to be highly expressed in periodontal ligaments of periodontitis. The VEGFA expression was up-regulated in inflamed PDLSCs compared to control, meanwhile the tube formation of HUVECs was improved when co-cultured with inflamed PDLSCs. Exosomes secretion of PDSLCs was augmented by inflammation, and promoted angiogenesis of HUVECs, whereas blocking secretion of exosomes led to degenerated angiogenesis of HUVECs. Exosome-trasferred VEGFA was proven to be the crucial communicator between PDLSCs and HUVECs. Inflammation inhibited miR-17-5p expression of PDLSCs and relieved its target VEGFA. However, overexpression of miR-17-5p blocked the pro-angiogenic ability of inflamed PDLSCs. In conclusion, the findings indicated that vascularization of periodontal ligaments was enhanced, and inflammatory micro-environment of periodontitis facilitated pro-angiogenesis of PDLSCs through regulating exosome-mediated transfer of VEGFA, which was targeted by miR-17-5p.

Microcirculation changes in gingival tissue after ultrasonic tooth preparation in beagle dogs

Abstract Ultrasonic wave technology is widely used during dental treatments. We previously demonstrated that this method protects the gingival tissue. However, the physiological change on the gingival microvasculature caused by this method remains unclear. Objective The aim of this study was to investigate the relationship between the morphological and physiological effects on gingival microcirculation when preparing teeth, using the conventional dental turbine or ultrasonic method. Methodology The lower premolar teeth of beagle dogs were prepared along the gingival margin by using a dental turbine or ultrasonic wave instrument. Gingival vasculature changes were investigated using scanning electron microscopy for corrosion resin casts. Gingival blood flow at the preparation site was determined simultaneously by laser Doppler flowmetry. These assessments were performed immediately (Day 0), at 7 days and 30 days after tooth preparation. Results At day 0, in the turbine group, blood vessels were destroyed and some resin leaked. Furthermore, gingival blood flow at the site was significantly increased. In contrast, the ultrasonic group demonstrated nearly normal vasculature and gingival blood flow similar to the non-prepared group for 30 days after preparation. No significant alterations occurred in gingival circulation 30 days after either preparation; however, the turbine group revealed obvious morphological changes. Conclusions Based on multiple approach analyses, this study demonstrated that ultrasonic waves are useful for microvascular protection in tooth preparation. Compared with a dental turbine, ultrasonic wave instruments caused minimal damage to gingival microcirculation. Tooth preparation using ultrasonic wave instruments could be valuable for protecting periodontal tissue.

A Novel Approach to Monitoring Graft Neovascularization in the Human Gingiva.

Laser speckle contrast imaging (LSCI) is a novel method for measuring superficial blood perfusion over large areas. Since it is non-invasive and avoids direct contact with the measured area, it is suitable for monitoring blood flow changes during wound healing in human patients. Vestibuloplasty is periodontal surgery to the oral vestibule, aiming to restore vestibular depth with simultaneous enlargement of the keratinized gingiva. In this special clinical case, a split thickness flap was elevated at the first upper premolar and a xenogenic collagen matrix was adapted to the resulting recipient bed. LSCI was used to monitor the re- and neovascularization of the graft and the surrounding mucosa for one year. A protocol is introduced for the correct adjustment of microcirculation measurement in the oral mucosa, highlighting difficulties and possible failures. The clinical case study presented demonstrated that - following the appropriate protocol - LSCI is a suitable and reliable method for following up microcirculation in a healing wound in the human oral mucosa and gives useful information on graft integration.

Immunohistochemical study of CD34 and podoplanin in periodontal disease.

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the angiogenesis and lymphangiogenesis in gingival tissue biopsy specimens of individuals with clinically healthy gingiva, chronic gingivitis, and chronic periodontitis (n = 30 per clinical condition). MATERIAL AND METHODS: Histological sections were stained using hematoxylin and eosin as well as immunohistochemically with hematopoietic progenitor cell antigen CD34 and podoplanin (PDPN) antibodies to evaluate the microvascular count, area, and perimeter of blood and lymphatic vessels, respectively. RESULTS: The results revealed a correlation between the microvascular count of blood and lymphatic vessels (P = 0.03; however, in individuals with chronic periodontitis, fewer lymphatic vessels were present than in the clinically healthy gingival tissue (P = 0.01), which was not observed in the case of microvascular area and perimeter. Podoplanin labeling was present in the epithelium, and the intensity of labeling was positively correlated to the intensity of the inflammatory infiltrate (P = 0.03). CONCLUSION: In this study, we concluded that an increase in the number of blood and lymphatic vessels was not observed in bouth gingivitis and periodontitis samples. Podoplanin expression is highly associated with an increased inflammatory infiltration suggesting that PDPN might play an additional role in periodontal disease, other than solely as a lymphangiogenesis marker.

A mixed form of intravascular papillary endothelial hyperplasia in an uncommon location: case and literature review.

Intravascular papillary endothelial hyperplasia (IPEH) is an unusual benign, non-neoplastic vascular lesion that usually occurs in skin, but is uncommon in the oral cavity. Herein, we review the pertinent literature of oraiiPEH and report a new mixed form. A 61-year- old man presented with an ulcerated nodule in the lingual portion of the gingiva related to the left mandibular canine. An excisional biopsy was performed presuming the clinical diagnosis of pyogenic granuloma. Histopathological analysis showed areas of granulation tissue consistent with pyogenic  granuloma. But in  addition, there  were thin-wall dilated vessels with papillary projections of endothelial cells producing vascular channels, associated with  an area of  organizing  thrombus. These microscopic findings led to the diagnosis of pyogenic  granuloma  associated with  IPEH. The immunohistochemical  reactions revealed a diffuse positivity of the vascular cells for CD-34 and smooth muscle actin antibodies.In addition,there was partial positivity for podoplanin and negativity for CD-1OS in the IPEH areas. No signs of recurrence were observed after 6 months of follow-up. The most prevalent site of IPEH in the oral region is the lower lip. IPEH is slightly more common in women and exhibits peaks of prevalence between the fourth and sixth decades of life.

Gingival Perfusion and Tissue Biomarkers During Early Healing of Postextraction Regenerative Procedures: A Prospective Case Series.

BACKGROUND: Postextraction alveolar bone loss, mostly affecting the buccal plate, occurs despite regenerative procedures. To better understand possible determinants, this prospective case series assesses gingival blood perfusion and tissue molecular responses in relation to postextraction regenerative outcomes. METHODS: Adults scheduled to receive bone grafting in maxillary, non-molar, single-tooth extraction sites were recruited. Clinical documentation included the following: 1) probing depth (PD); 2) keratinized tissue width (KT); 3) tissue biotype (TB); and 4) plaque level. Wound closure was clinically evaluated. Gingival blood perfusion was measured by laser Doppler flowmetry (LDF). Wound fluid (WF) and gingival biopsies were analyzed for protein levels and gene expression, respectively, of relevant molecular markers. Bone healing outcomes were determined radiographically (cone-beam computed tomography). Healing was followed for 4 months. RESULTS: Data from 15 patients are reported. Postoperatively, neither complications nor changes in PD, KT, or TB were observed. LDF revealed decreased perfusion followed by hyperemia that persisted for 1 month (P ≤0.05). WF levels of angiopoietin-2, interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α), and vascular endothelial growth factor peaked on day 6 (P ≤0.05) and decreased thereafter. Only IL-8 and TNF-α exhibited increased gene expression. Linear bone changes were negligible. Volumetric bone changes were minimal but statistically significant, with more bone loss when membrane was used (P = 0.05). CONCLUSIONS: Gingival blood perfusion after postextraction bone regenerative procedures follows an ischemia-reperfusion model. Transient increases in angiogenic factor levels and prolonged hyperemia characterize the soft tissue response. These soft tissue responses do not determine radiographic bone changes.

Vascularization after treatment of gingival recession defects with platelet-rich fibrin or connective tissue graft.

OBJECTIVE: The aim of this study was to evaluate histologically the following treatment of bilateral localized gingival recessions with coronally advanced flap (CAF) combined with platelet-rich fibrin (PRF) or subepithelial connective tissue graft (SCTG). MATERIALS AND METHODS: Tissue samples were harvested from 14 subjects either 1 or 6 months after the surgeries. The 2-mm punch biopsies were obtained from the mid-portion of the grafted sites. Neutral buffered formalin fixed, paraffin-embedded 5-µm thick tissue sections were stained with hematoxylin eosin and Masson's trichrome in order to analyze the collagen framework, epithelium thickness and rete-peg length. Multiple sequential sections were cut from paraffin-embedded blocks of tissue and immunohistochemically prepared for detection of vascular endothelial growth factor, CD31 and CD34, for the assessment of vascularization. RESULTS: Rete peg formation was significantly increased in the sites treated with PRF compared to the SCTG group after 6 months (p < 0.05). On the contrary, the number of vessels was increased in the SCTG group compared to the PRF group after 6 months (p < 0.05). No statistically significant differences were observed in the collagen density. Staining intensity of CD31 increased in submucosal area of PRF group than SCTG group after 1 month. Higher staining intensity of CD34 was observed in the submucosal area of PRF group compared with SCTG group after 6 months. CONCLUSIONS: The results of the present study suggest that in histological evaluation because of its biological compounds, PRF results earlier vessel formation and tissue maturation compared to connective tissue graft. CLINICAL RELEVANCE: PRF regulated the vascular response associated with an earlier wound healing.

Immunohistochemical Evaluation of Angiogenesis Related Markers in Pyogenic Granuloma of Gingiva.

BACKGROUND: Pyogenic granuloma is a common non-neoplastic connective tissue proliferation. ICAM-1 and VCAM-1 are vascular adhesion molecules and CD34 is a marker for evaluation of angiogenesis. The purpose of this study was to compare the immunohistochemical expression of ICAM-1, VCAM-1 and CD34 in oral pyogenic granuloma and normal gingiva. MATERIALS AND METHODS: This study was performed on thirty five formalin-fixed, paraffin embedded samples of gingival pyogenic granuloma. Also we used thirty five paraffined blocks of normal gingiva as control group which were taken from crown lengthening surgery. We employed immunohistochemistry staining for our prepared microscopic slides using monoclonal mouse anti-human antibodies against ICAM-1 (CD54), VCAM-1 (CD106) and CD34. Slides were examined under light microscope and then the mean amount of stained vessels also known as microvascular density (MVD) in highly vascularized areas (hot spots) was measured. Paired t-test and repeated measures ANOVA were used to compare the difference between quantitative variables and Chi-square test for qualitative variables in different groups. Pearson correlation coefficient was used to compare relations between quantitative variables. P<0.05 was considered significant. RESULTS: The mean of MVD for ICAM-1, VCAM-1 and CD34 was significantly higher in pyogenic granuloma than normal gingiva (p<0.001 and p<0.001 and p<0.001, respectively). Expression of CD34 in pyogenic granuloma was significantly higher than ICAM-1 and VCAM-1 (P<0.001). Besides, expression of ICAM-1 in normal gingiva, was significantly lower than two other markers (p<0.001). CONCLUSIONS: Regarding the results, it seems that ICAM-1, VCAM-1 and CD34 are useful biomarkers in evaluation of vascular and inflammatory lesions such as gingival pyogenic granuloma and the results indicate the role of these biomarkers in pathogenesis of oral pyogenic granuloma.

Transglutaminase 2 May Be Associated with Peri-implant Gingival Overgrowth: Preliminary Assessments.

UNLABELLED: Tissue transglutaminase 2 (TG2) is ubiquitously expressed in normal tissues and plays an important role in the pathophysiology of wound healing. An increase in periodontal tissues has been previously reported in cyclosporine-induced gingival overgrowth. PURPOSE: The aim of this study was to explore associations between TG2 expression and the vascularization and maturation processes of peri-implant soft tissues over time. MATERIALS AND METHODS: Edentulous patients proposed for mandibular implant-retained overdentures were included in the study. Biopsies of the peri-implant mucosa were performed at the first surgical stage and at 4, 8, and 12 months after prosthetic load. A follow-up program was directed to record plaque indexes, bleeding on probing data, and pocket probing depth around implants. An evaluation of the vessels' density was carried out by digital virtual microscopy and using an immunohistochemistry approach (antibodies anti-CD31, anti-TG2). A robust multivariable regression model was implemented. RESULTS: According to model results, blood vessel count and probing (as a marker of gingival overgrowth in absence of plaque) significantly decrease over time and are associated with TG2, particularly for values above the median. CONCLUSION: The association of an increased TG2 expression in the extracellular matrix might have a significant impact in the development of gingival overgrowth around a loaded implant.

Microvessel Density Evaluation of the Effect of Enamel Matrix Derivative on Soft Tissue After Implant Placement: A Preliminary Study.

Enamel matrix derivative (EMD) is commonly used in periodontal therapy and has been used successfully for periodontal regeneration. In addition, this material has a possible angiogenic effect that has been associated with enhanced wound healing. The aim of this study was to evaluate the effect of EMD on microvessel density (angiogenesis) on the soft tissues surrounding newly placed implants after 14 days. Five patients were selected, each requiring at least one implant on each side of the maxilla, in a split-mouth experimental design. The implants were placed in a two-stage procedure. Each side was then randomized as test or control. On the test side, 0.1 mL of EMD was topically applied to the soft tissues surrounding the implants, while the control side did not receive any treatment. Second-stage surgery was performed after 14 days. A 6-mm punch biopsy was performed for each implant, with the samples subsequently prepared for histology and immunohistochemistry. Quantitative vascularization analysis was performed, which involved counting three areas or "hotspots" containing vessels strongly positive for CD34 and CD105, a pan-endothelial and new vessel marker, respectively. There was no significant difference between test and control groups when evaluating the formation of new blood vessels. The total number of blood vessels, however, was significantly higher in the group treated with EMD (test group). Within the limits of the present study, it can be concluded that topical application of EMD on the soft tissues surrounding newly placed implants resulted in an increased number of blood vessels at 14 days, suggesting that EMD may play a beneficial role in this aspect of wound healing.

Assessment of heat provocation tests on the human gingiva: the effect of periodontal disease and smoking.

UNLABELLED: Periodontal inflammation is associated with morphological changes in the blood vessels which may influence the regulation of gingival blood flow (GBF). Our aim was to adapt the heat provocation test to the human gingiva to assess vascular reactivity in periodontal inflammation. METHOD: GBF was recorded by Laser Doppler Flowmetry before and after heat provocation in healthy volunteers (n = 50). Heat was generated either by warm saline or a halogen lamp. The latter method was also utilized for a heat test in non-smoking and smoking patients with periodontal inflammation. The circulatory parameters were correlated to the inflammatory marker, i.e. gingival crevicular fluid (GCF) production measured by Periotron. RESULTS: Local application of heat caused a rapid, significant and transient increase in GBF regardless of the method used. The increase in the speed and not in the concentration of moving blood cells was responsible for increased GBF. Higher GCF values were correlated with increased peak flow, flux pulse amplitude and faster restoration of GBF after the test in non-smokers, but not in smokers. CONCLUSIONS: The heat test could be a valuable tool to check the vascular reactivity of gingival vessels. Moderate periodontal inflammation may facilitate gingival vascular responsiveness which can be suppressed by smoking.

A rat model of radiation injury in the mandibular area.

BACKGROUND: Radiation technology focuses on delivering the radiation as precisely as possible to the tumor, nonetheless both acute and long-term damage to surrounding normal tissue may develop. Injuries to the surrounding normal tissue after radiotherapy of head and neck cancer are difficult to manage. An animal model is needed to elucidate good treatment modalities. The aim of this study was to establish a rat model where a certain radiation dose gives reproducible tissue reactions in the mandibular area corresponding to injuries obtained in humans. METHOD: The left mandible of male Sprague Dawley rats was irradiated by external radiotherapy (single fraction 15 Gy, total dose 75 Gy) every second week five times. Endpoint was six weeks after last radiation treatment, and the test group was compared to non-irradiated controls. Morphological alterations of the soft tissues, bone and tooth formation, as well as alterations of salivation, vascularity and collagen content were assessed. An unpaired, non-parametric Mann-Whitney test was used to compare the statistical differences between the groups. RESULTS: Analysis of the soft tissues and mandible within the radiation field revealed severe unilateral alopecia and dermatitis of the skin, extensive inflammation of the submandibular gland with loss of serous secretory cells, hyperkeratinization and dense connective fiber bundles of the gingival tissue, and disturbed tooth development with necrosis of the pulp. Production of saliva and the vascularity of the soft tissues were significantly reduced. Furthermore, the collagen fibril diameter was larger and the collagen network denser compared to non-irradiated control rats. CONCLUSION: We have established an animal model of radiation injury demonstrating physiological and histological changes corresponding to human radiation injuries, which can be used for future therapeutic evaluations.

In vitro study on regeneration of periodontal tissue microvasculature using human dedifferentiated fat cells.

BACKGROUND: Human dedifferentiated fat cells (HDFATs) may be a new cell type suitable for regenerative therapies. The aim of this study is to assess the potential of HDFATs for vascular regeneration of periodontal tissue. To do this, HDFATs and human gingival endothelial cells (HGECs) were cocultivated, and vascular regeneration was examined in vitro. METHODS: HDFATs were isolated from subcutaneous adipose tissue, and HGECs were isolated from gingival cells using anti-cluster of differentiation 31 antibody-coated magnetic beads. HDFATs were cocultured with HGECs in microvascular endothelial cell growth medium-2 (EGM-2MV) for 7 days. Expression of endothelial cell (EC) markers, the formation of capillary-like tubes, and the expression of pericyte markers were determined. RESULTS: HDFATs, cultured in EGM-2MV or cocultured with HGECs, expressed EC markers. HDFATs in both conditions initiated tube formation within 5 hours of seeding and formed extensive capillary-like structures within 12 hours. These structures disintegrated within 24 hours when cells were cultured in EGM-2MV alone, whereas cocultured HDFATs maintained tubes for >24 hours. Cocultured HDFATs significantly increased expression of pericyte markers, a cell type associated with microvasculature. CONCLUSION: HDFATs possess the ability to express EC markers, and coculture with HGECs promotes differentiation into pericytes involved in the maturation and stabilization of the microvasculature.

A comparative assessment of maxillary perfusion between two different Le Fort I osteotomy techniques.

Compromised maxillary perfusion following Le Fort I osteotomy is a potentially serious complication resulting in hard and/or soft tissue loss. The aim of this study was to compare the change in perfusion between two techniques of posterior maxillary disjunction by intraoperative measurement of maxillary gingival blood flow (GBF). Further, we sought to correlate the association of the movement of the maxilla and estimated blood loss as factors. The study population comprised 38 individuals, divided equally into two groups: a pterygoid disjunction group and a third molar socket disjunction group. GBF was measured using Doppler flowmetry. A P-value of <0.05 was considered significant. There was a significant drop in GBF in both groups. However, there was no significant difference between the groups based on magnitude of blood flow drop. Superior repositioning of the osteotomized maxilla caused the greatest drop in GBF, which was statistically significant. There was significantly less blood loss in the pterygoid disjunction group. In conclusion, Le Fort I osteotomy causes a significant decrease in GBF. The technique used for posterior maxillary disjunction does not influence the magnitude of drop in perfusion. There is a significant correlation of other factors such as the effect of superior repositioning of the maxilla and blood loss with the osteotomy techniques.

Histological evaluation of oral maintenance programs upon gingival condition in orthodontic patients.

The aim of the study was to conduct a histological evaluation of gingival condition in patients under orthodontic treatment with fixed appliances, according to different oral hygiene maintenance programs. We performed a randomized prospective study on 36 patients with fixed orthodontic appliances (17-25 years of age) divided in three study groups. The investigations were represented by measurements of plaque index and sulcular bleeding index, followed by pathological examination of specimens from gingival tissue. Treatment of orthodontic patients must follow an interdisciplinary approach. All modalities of oral hygiene procedures and their effect on the periodontal tissues must be explained to the patient prior to fixed orthodontic treatment. Fixed orthodontics do not induce periodontal disease if basic principles of oral hygiene are followed in compliant patients, which are correctly instructed to deal with real challenge, represented by complete elimination of debris and bacterial accumulation.

Comparative evaluation of the marginal gingival epithelium in smokers and nonsmokers: a histomorphometric and immunohistochemical study.

Smoking is one of the strongest predictors of attachment and bone loss. Smokers demonstrate reduced inflammatory clinical signs, which could be due to local vasoconstriction and increased gingival epithelial thickness. The byproducts originating from tobacco oxidation modify the clinical characteristics and progression of periodontal disease. The aim of this study was to investigate the relationship between the thickness of marginal gingival oral epithelium, sulcular bleeding, and vascular caliber and density of the microvessels in smokers and nonsmokers with and without periodontitis and to better understand the role of smoking in relation to periodontal disease. One hundred twenty individuals were enrolled in this study and divided into four groups comprising 30 participants each. The clinical measurements carried out included probing depth, clinical attachment loss, and bleeding index, along with gingival biopsy specimens, which were subjected to immunohistochemical and histomorphometric analysis. Correlation of the clinical and histologic features revealed that smokers presented with fewer inflammatory signs, had fewer vascular elements in the subepithelial connective tissue layer, and showed a resultant increase in epithelial thickness irrespective of the presence of periodontitis. There was a mean increase of epithelial thickness of 181.3 µm (suprapapillary epithelial thickness [SET]) to 380.2 µm (maximal epithelial thickness [MET]) in smokers with periodontitis as compared to 157.4 µm (SET) to 325.3 µm (MET) in nonsmokers with periodontitis. The mean microvascular density in smokers with periodontitis was 325.4 per mm, which was found to be statistically significantly less than that of nonsmokers with periodontitis, who had a mean value of 412.13 per mm. The vessel caliber also was reduced in smokers, with a mean value ranging from 4.7 to 6.1 µm compared with a mean of 6.2 to 9.2 µm in nonsmokers, irrespective of the presence of periodontitis. Statistically significant differences were found in vascular density and thickness of gingival epithelium between smokers and nonsmokers with and without periodontitis. These differences may impact the progression of periodontal disease.