Root coverage by coronally advanced flap with connective tissue graft and/or enamel matrix derivative: a meta-analysis.

BACKGROUND AND OBJECTIVE: Previous systematic reviews have reported that the use of a coronally advanced flap (CAF) combined with a connective tissue graft (CTG) or enamel matrix derivative (EMD) is more likely to achieve complete root coverage (CRC) than other modalities. However, the details of periodontal parameters and comparisons among a variety of combinations of CAF with CTG and/or EMD are left to be investigated. This study aimed to analyze the differences in periodontal parameters between these treatment modalities. MATERIAL AND METHODS: A literature search was performed using the Cochrane library and MEDLINE (PubMed) for studies focused on the treatment of gingival recession (Miller Class I, II and III) with CAF alone or combined with CTG, EMD or both up to December 2011. Randomized controlled clinical trials with a follow-up duration ≥ 6 mo were included. The outcome analysis included changes in periodontal probing depth (PPD), clinical attachment level, recession depth (RED) and keratinized tissue width (KTW). RESULTS: Thirteen randomized controlled clinical trials, including 529 Miller Class I-III defects from 321 patients were included. For an increase in KTW, CAF + CTG significantly improved more than CAF alone. CAF + EMD also gained more KTW than CAF alone. EMD reduced PPD, however, a significant difference was not found. Furthermore, the effects on changes of RED and clinical attachment level were not identified in the study. CONCLUSION: When combined with CAF, CTG contributed more in the increase of KTW, while EMD seemed helpful for wound healing by its potential in PPD reduction. However, further research is needed to clarify the effects on changes in RED and clinical attachment level.

Nrf-2 regulates cyclosporine-stimulated HO-1 expression in gingiva.

Cyclosporine-A (CsA) stimulates heme oxygenase-1 (HO-1) expression in the gingiva, but the regulation and the role of HO-1 in gingival overgrowth are not well-understood. HO-1 is regulated by several transcription factors, such as nuclear factor-κB (NF-κB) and nuclear factor erythroid-2-related factor 2 (Nrf-2). The aim of this study was to examine the role of Nrf-2 in the regulation of CsA-stimulated HO-1 expression in human gingival fibroblasts. Nrf-2 siRNA (siNrf-2), NF-κB, kinase inhibitors, and sulforaphane (SFN) were used to examine the nuclear translocation of Nrf-2 and expression of HO-1 and transforming growth factor-ß1 (TGF-ß1) in cells. Treatment with siNrf-2, but not with an NF-κB inhibitor, reduced CsA-stimulated HO-1 mRNA expression. ERK inhibition significantly decreased CsA-stimulated Nrf-2 nuclear translocation and HO-1 mRNA expression. Pre-treatment with SFN showed that HO-1 plays a role in attenuating CsA-mediated TGF-ß1 expressions. These findings suggest that CsA-stimulated HO-1 expression is mediated through the activation of ERK, and that Nrf-2 plays a protective role against CsA-induced gingival fibrosis by modulating collagen turnover-related genes.

Three-dimensional analysis of the root morphology of mandibular first molars with distolingual roots.

AIM: To determine the prevalence of distolingual roots in mandibular first molar teeth in Taiwanese Han Chinese, and its impact on root morphology. METHODOLOGY: The presence of distolingual roots in 375 subjects (521 molars) were assessed from 624 patients attending the dental clinics of medical centres around Taiwan island from August 2004 to April 2007 using computed tomography. The following observations were made: (i) numbers of roots and canals, (ii) mesial and distal root types and (iii) levels of furca in the molars presence or absence of distolingual root. RESULTS: The mean age of the subject was 45; 43% were women. Among all the examined molars, 56%, 27% and 18% were two-, three- and four-rooted, respectively. Two per cent, 72% and 26% of molars had two, three and four canals, respectively. All of the four-rooted molars had four canals, but all of the molars with four canals varied in the number of roots. All molars with distolingual roots had two mesial canals. Bilateral consistency in terms of distolingual root, root canal number, root number and root type was observed in subjects with bilateral molars. In molars with distolingual roots, a higher prevalence of two mesial roots and a shorter mesial root trunk were observed than in teeth without distolingual roots. CONCLUSIONS: A distolingual root was found in 22% of molars and in 24% of the subjects examined. Most subjects with a distolingual root had them bilaterally. The presence of a distolingual root was associated with variation in the root morphology, including the furcation level, the root type and the number of roots and canals.

Expression and bioactivities of endothelin-1 in gingiva during cyclosporine A treatment.

BACKGROUND AND OBJECTIVE: This study aimed to evaluate the expression and bioactivities of endothelin-1 (ET-1) in gingiva during cyclosporine A (CsA) treatment. MATERIAL AND METHODS: After establishing edentulous ridges, experimental rats were fed 30 mg/kg/day CsA while control animals received mineral oil for 4 weeks, after which a reverse transcription-polymerase chain reaction (RT-PCR) and/or immunohistochemistry was used to examine the expression of ET-1, its receptors, proliferating cell nuclear antigen (PCNA) and inducible nitric oxide synthase (iNOS) in gingivae. The roles of the endothelin receptors A and B (ET(A) and ET(B)) in CsA-enhanced expression of PCNA and iNOS were examined in cultured human gingival fibroblasts pretreated with receptor antagonists, by immunocytochemistry and RT-PCR, respectively. RESULTS: The mRNA expression of ET-1, ET(A) and ET(B), as well as of PCNA and iNOS, was significantly greater in edentulous gingiva that received CsA compared with control gingiva. Immunohistochemistry revealed more cells positively stained for ET-1 and its receptors in the tissues of CsA-treated rats than in those of control rats. In fibroblast cultures, enhanced mRNA expression of ET-1, ET(A) and ET(B) was observed after CsA treatment at the concentrations of 10 and 100 ng/mL. Cyclosporine A-enhanced PCNA expression was somewhat reduced by blockade of ET(A), but not ET(B), whereas iNOS expression was somewhat reduced by blockade of ET(B). CONCLUSION: Based on the present findings, we suggest that: (1) CsA upregulates the gingival expression of ET-1 and its receptors; and (2) ET(A) and ET(B) have different bioactivities, ET(A) being involved in cell proliferation and ET(B) being associated with iNOS expression.

Tetracycline release from tripolyphosphate-chitosan cross-linked sponge: a preliminary in vitro study.

BACKGROUND AND OBJECTIVE: The aim of this study was to design a tripolyphosphate-chitosan cross-linked tetracycline-containing (TPP-TC) sponge that slowly releases tetracycline, for future periodontal applications. MATERIAL AND METHODS: Chitosan sponge was made by freezing and drying 2.5% chitosan solution. Tripolyphosphate-chitosan cross-linked (TPP) sponge was made by immersing the chitosan sponge in tripolyphosphate solution and air drying it. Tetracycline-containing chitosan (TC) sponge was prepared by freezing and drying a mixture of chitosan and tetracycline. TPP-TC sponge was made by immersing the TC sponge in tripolyphosphate solution. The weight, thickness and diameter of the four chitosan sponges were recorded. Their surface microstructures were inspected using scanning electron microscopy. The amount of tetracycline released from the sponges was analyzed by spectrophotometry. Antimicrobial activities of the residual sponges were tested against Staphylococcus aureus and Escherichia coli. RESULTS: The topography of the scaffolds was intact after the addition of tetracycline. However, increased surface irregularities were noted. In sponges with tripolyphosphate, intensified surface folding was observed. The weight of the sponges increased after tripolyphosphate and tetracycline were added, but their thicknesses and diameters decreased after cross-linking. Tetracycline was detected in the solution containing TPP-TC sponges until day 11. On day 7, the tetracycline released from TC sponges was less than that released from TPP-TC sponges. Bacterial growth was inhibited by sponges containing tetracycline. The inhibitory effect of the TPP-TC sponges was detectable until day 11. CONCLUSION: Our data showed that TPP-TC sponge was suitable as a slow-release device for tetracycline and that it maintained antimicrobial effects against the bacteria tested for up to 11 d.

Dynamic recording of irrigating fluid distribution in root canals using thermal image analysis.

AIM: To investigate the influence of the size and the depth of insertion of irrigating needles, and the diameter of the master apical file on flow distribution during fluid irrigation in root canals. METHODOLOGY: Stepback canal instrumentation was employed on seven extracted human single canal teeth. The size of the master apical files ranged from sizes 25, 30, 35, 40, 45, 50 to size 80 within the seven teeth, respectively. A thermal imaging system (ThermaCAM; National Instruments Co., Austin, TX, USA) was used to record the dynamic fluid distribution following root canal preparation. The dynamic fluid distribution was analysed during irrigation by insertion of different irrigating needle tips (23, 25 and 27 gauge) at various depths (3, 6 and 9 mm) from the root apex. The whole process of irrigation was recorded by a video camera and analysed by two observers separately. The success of the irrigation process was defined when the irrigant was able to flow into to the apical region immediately after injection. RESULTS: The aqueous irrigant was flushed into the apical region when a size 27 gauge irrigating needle was placed into a size 30 canal at a point 3 mm from the apical stop. When the same needle tip was placed 6 mm from the root canal apex, successful irrigation was achieved only in the canals prepared to size 50 or larger. When a size 25 gauge irrigating needle was placed 3 mm from the working length, the canal size had to be no <45 to allow for successful irrigation. When a size 23 gauge needle was placed at the same position, the canal needed to be prepared to size 50 to allow thorough irrigation of the apex. At 9 mm from the apical stop, none of the irrigating needles could achieve successful irrigation of any canal size. CONCLUSION: The flow distribution of root canal irrigation can be affected adversely by large diameter irrigating needles, by greater distances between the needle tip and the apical stop, and by narrow root canals.

Healing following tooth extraction in cyclosporine-fed rats.

Healing after tooth extraction was studied in rats treated with cyclosporine-A (CSA) for four weeks. Sixty male Sprague-Dawley rats were assigned to one of three groups of 20 rats each. The maxillary right molars were extracted from two groups; the third group served as a non-extraction control. The non-extraction group and one extraction group (vehicle control) received the solvent mineral oil daily, and the other extraction group received 15 mg/kg CSA in mineral oil. Five rats from each group were killed 5, 10, 14 and 28 days after extraction and samples analyzed histologically. On days 5 and 10, bone volume was significantly lower and marrow volume significantly higher in both extraction groups than in the non-extraction group. The fractional-formation surfaces were significantly lower in the extraction groups than in the non-extraction group on day 5 only. Osteoid volume was significantly higher in the extraction vehicle control group than in the other two groups on days 10 and 14; however, the osteoid volume was higher in the CSA group than in the other two groups on day 28. On days 14 and 28, bone volume was lower and marrow volume higher in the CSA group than in the extraction vehicle control and non-extraction groups. On day 28, bony surface areas were significantly greater in the CSA group than in the extraction vehicle control and non-extraction groups. Soft-tissue evaluation showed significantly greater epithelial areas, connective tissue areas and total tissue areas in the CSA group than in the extraction vehicle control group on day 28, but not on day 14. These data suggest that CSA may influence healing of both the gingival tissue and the alveolar bony sockets in the tooth-extraction wound. Further detailed study is needed to identify the mechanisms responsible.

A histomorphological investigation of the effect of cyclosporin on trabecular bone of the rat mandibular condyle.

The effect of cyclosporin A (CSA) on the condylar trabecular bone was evaluated by microscopy. Twenty, 5-week-old male Sprague-Dawley rats were divided into a treated and a control group. Animals in the treated group received CSA, 15 mg/kg body weight, by gastric feeding daily for 4 weeks; controls received the vehicle only. Five animals from each group were killed at the end of weeks 2 and 4. After histological processing, 10 tissue sections from the mid-part of the mandibular condyle were examined. Generally, a histopathological osteopenia was observed around the condyle after CSA treatment, especially at the end of week 4. In the control animals, the trabecular bone volume steadily increased from weeks 2 to 4 (from 0.46+/-0.07 to 0.61+/-0.07 mm(3)/mm(3)). However, the bone volume was significantly less in the CSA group than in the control group at both times (0.33+/-0.02 vs 0.46+/-0.07 and 0.26+/-0.07 vs 0.61+/-0.07 mm(3)/mm(3) for CSA vs control group at the end of weeks 2 and 4, respectively). Conversely, an increased marrow volume was observed in the CSA group at both these times (0.60+/-0.02 vs 0.42+/-0.08 and 0.71+/-0.06 vs 0.31+/-0.06 mm(3)/mm(3) for CSA vs control group at the end of weeks 2 and 4, respectively). Decreases were also observed in trabecular thickness, osteoid seam width, osteoid volume and cortical bone width. Because trabecular bone mass, osteoid mass and cortical bone thickness all showed a decrease after CSA at both times, an inhibitory effect of CSA on trabecular bone formation in the mandibular condyle is proposed.

Cyclosporin-induced gingival overgrowth at the newly formed edentulous ridge in rats: a morphological and histometric evaluation.

BACKGROUND: Since cyclosporin A (CsA)-induced overgrowth seldom occurs at sites distant from teeth, the periodontal ligament has been considered significant. The aim of this study was to examine overgrowth occurrence at the edentulous ridge--the sites without the ligament--after CsA therapy in rats. METHODS: After extracting all right maxillary molars, 16 Sprague-Dawley rats underwent a 2-week healing period. The animals were separated into CsA and control groups. CsA rats received 15 mg/kg of CsA by gastric feeding for 4 weeks, while the control group received only mineral oil. At the end of study, all animals were sacrificed and stone models were immediately obtained by rubber-based impressions. The edentulous ridge morphology, including the bucco-lingual width and the vertical height, was measured on the models. For histometry, 10 sections were selected from the edentulous ridge of each animal after undecalcified tissue preparation. The soft tissue areas of the edentulous ridge and the trabecular bone morphology of the dental alveolus were measured. RESULTS: CsA therapy produced a significant increase of the ridge width and height, measured from the stone models, when compared to the control group. Under histometry, CsA resulted in a significant increase of the epithelium, connective tissue, and total soft tissue areas. The measured trabecular bone volume was affected by both examining factors: the drug therapy and the location of the dental alveolus. CsA therapy produced a significant loss of bone volume but a significant increase of the bone-specific surface area. Although the mean osteoid volume was similar between CsA and control groups, a significant decrease of the fractional formation surface in the CsA group was revealed. CONCLUSIONS: An enlarged edentulous ridge and an altered dental alveolar bone morphology were observed in CsA-treated animals at the end of the study; therefore, we suggest that CsA may induce not only a soft tissue overgrowth but also an alveolar bone alteration at the edentulous ridge. The hypothesis that tooth or periodontal ligament is an essential component for the overgrowth development is questioned.

Effects of cyclosporin A on dental alveolar bone: a histomorphometric study in rats.

BACKGROUND: We have previously reported cyclosporin A (CA)-induced osteopenia around the dental alveoli of the mandibular incisors of rats. The drug-induced tooth displacement and the regional anatomical complexity around the mandibular incisors might complicate the local effects of CA. Therefore, the purpose of this study was to evaluate the dental alveolar bone histomorphology around maxillary secondary molars in CA-treated rats and to further elucidate the effects of CA on the dental alveolus. METHODS: Twenty Sprague-Dawley rats were assigned to a CA and a control group. Animals in the CA group received CA (15 mg/kg) daily and the control rats received only mineral oil. At the end of weeks 2 and 4, five animals in each group were sacrificed. Dental alveoli around the maxillary second molar region were frontally sectioned and stained with toluidine blue by undecalcified histological processing. Ten serial tissue sections, 80 microm apart, were selected for histometric evaluation. Bone volume, bone-specific surface, and osteoid formation were measured at buccal, apical, and palatal locations in dental alveolus. RESULTS: Overall bone mass in dental alveolus decreased more in the CA group than in the control group at both observation intervals. All histometric measurements, except the bone-specific surface, were significantly affected by the alveolar location (palatal, apical, and buccal) and CA therapy (P= 0.004 and <0.001, 0.001 and <0.001, 0.004 and <0.001 for drug therapy and location of the dental alveolus in bone volume, marrow volume, and the ratio of bone surface to volume, respectively). Decreased bone volume, but increased marrow volume, were noted in the CA group compared to the control group. Although the alveolar bone surface area did not differ between the CA group and the control group, greater alveolar surface-to-volume ratio was noted in the CA group. For osteoid, more decreased volume, seam width, and fractional formation surface were observed in the CA group compared to the control group (P <0.001, <0.001, and = 0.046 in osteoid volume, seam width volume, and formation surface, respectively). CONCLUSIONS: Because the bone mass and the osteoid formation in the dental alveolus around the maxillary molar region showed a decrease after CA exposure, we conclude that this drug has inhibitory effects on the dental alveoli.

Mandibular second molar periodontal status after third molar extraction.

BACKGROUND: Extraction and treatment of third molars have been cited as causing periodontal problems. To evaluate the long-term effects of third molar extraction on the periodontal health of the mandibular second molar, a comparison of the periodontal status was performed around 2 groups of mandibular second molars, with and without third molar extraction. METHODS: A total of 312 sites in 57 adult periodontitis patients were examined and the buccal and lingual locations of the mesial and distal root surfaces around the second molars were recorded. Two-hundred and thirty-two sites were experimental teeth; i.e., third molars had been surgically removed more than 5 years ago, 80 sites served as control molars; i.e., congenitally missing third molars. Clinical periodontal parameters including probing depth, attachment loss, and gingival recession and radiographic intrabony level were measured. The effects of the surgery and the examination (buccal or lingual) locations on the measurements were statistically analyzed. RESULTS: Neither extraction history nor examination location affected the probing depth on mesial surfaces. However, significant effects of the surgical history on the probing depth were observed on the distal surfaces. Similar results of greater attachment loss and radiographic alveolar bone loss were observed only at the distal sites of the experimental group. In addition, the increased radiographic bone loss was only found at the distal sites (adjacent to the surgical location) and not at the mesial sites (distant from the surgical location) on the experimental group. CONCLUSIONS: In this study, greater periodontal breakdown, including probing depth, attachment loss, and radiographic alveolar bone loss, was found at the distal sites, but not at the mesial sites, of the experimental molars where the third molar was surgically extracted compared with the control teeth (no surgery). In the experimental molars, more radiographic bone loss was found at the sites adjacent to the surgical location than at the sites distant to the surgical location. Therefore, we suggest that the surgical removal of the mandibular third molar may lead to a periodontal breakdown on the distal surface of the second molar. Periodontal re-evaluation after the initial healing of third molar extraction is indicated.

7The yeast mRNA-binding protein Npl3p interacts with the cap-binding complex.

A number of RNA-binding proteins are associated with mRNAs in both the nucleus and the cytoplasm. One of these, Npl3p, is a heterogeneous nuclear ribonucleoprotein-like protein with some similarity to SR proteins and is essential for growth in the yeast S. cerevisiae. Temperature-sensitive alleles have defects in the export of mRNA out of the nucleus (1). In this report, we define a genetic relationship between NPL3 and the nonessential genes encoding the subunits of the cap-binding complex (CBP80 and CBP20). Deletion of CBP80 or CBP20 in combination with certain temperature-sensitive npl3 mutant alleles fail to grow and thus display a synthetic lethal relationship. Further evidence of an interaction between Npl3p and the cap-binding complex was revealed by co-immunoprecipitation experiments; Cbp80p and Cbp20p specifically co-precipitate with Npl3p. However, the interaction of Npl3p with Cbp80p depends on both the presence of Cbp20p and RNA. In addition, we show that Cbp80p is capable of shuttling between the nucleus and the cytoplasm in a manner dependent on the ongoing synthesis of RNA. Taken together, these data support a model whereby mRNAs are co-transcriptionally packaged by proteins including Npl3p and cap-binding complex for export out of the nucleus.

Effects of cyclosporin A on the mandibular condylar cartilage in rats.

Twenty, 5-week-old, male, Sprague-Dawley rats were divided into a control and a cyclosporin A (CSA) group for evaluating effects of the drug on condylar cartilage. Animals in the treatment group daily received CSA (15 mg/kg body wt) in mineral oil by gastric feeding over a 4-week observation interval. Control animals received mineral oil only. Five animals from each group were killed at weeks 2 and 4 of study. After histological processing, five tissue sections from the mid-region of the condyle were selected and examined. Three compositional zones (articular fibrous, proliferative, and hypertrophic) of the superior, posteriosuperior and posterior regions of the condylar cartilage were evaluated by light microscopy. At week 2, total condylar cartilage thickness was similar in the CSA and control groups, but the thickness of each zone was altered in CSA-treated animals, including a decrease of the fibrous and proliferative zones and an increase in hypertrophic zone compared to control (P<0.05). At week 4, CSA-treated animals exhibited overall decreased cartilage thickness, including decreased thickness of each zone compared to control (P<0.05). The results suggest that CSA has an inhibitory effect on the maturation of the mandibular condyle in rats.

Carious lesions in the heroin addicted patient. A case report.

Heroin abuse is destroying the health of many individuals in our society. Much of the information that has appeared in the literature has concerned itself with the general health of addicts; the oral health status of these individuals has not been studied to the same extent. This report will present and discuss the management of a case involving the effects of long-term heroin abuse on the dentition.

Nifedipine-induced gingival overgrowth in rats: brief review and experimental study.

The first case report of gingival overgrowth induced by nifedipine (NIF), a calcium-beta blocker, was in 1984. However, the association between gingival alterations and the drug therapy of sodium diphenyl hydantoinate was initially described in 1939. The purpose of the experimental study was to examine the effect of NIF on gingival morphology in an animal model. Forty-five male Sprague-Dawley rats were randomly divided into 3 groups. Animals in each group daily received NIF in dimethyl sulfoxide by gastric feeding at a dosage of 0 (control), 30, or 50 mg/kg body weight for 9 weeks. Gingival gross morphology was assessed tri-weekly from stone models obtained from the mandibular incisal region. Animals were sacrificed at the end of study and tissue blocks were processed for histopathologic and histometric evaluation. Histometric analysis was performed at 5 selected tissue levels. Macro- and microscopic significantly increased gingival dimensions were demonstrated in NIF-treated animals compared to control. Although a fibrovascular tissue was observed in the tooth-gingiva interface for both NIF-treated and control animals, it was thicker and appeared earlier in NIF-treated animals. The results of the present study suggest that gingival overgrowth can be induced by NIF in rats and that the gingival overgrowth appears dose dependent.

Arginine methylation facilitates the nuclear export of hnRNP proteins.

Eukaryotic mRNA processing and export is mediated by various heterogeneous nuclear ribonucleoproteins (hnRNPs). Many of these hnRNPs are methylated on arginine residues. In the yeast, Saccharomyces cerevisiae, the predominant enzyme responsible for arginine methylation is Hmt1p. Hmt1p methylates both Npl3p and Hrp1p, which are shuttling hnRNPs involved in mRNA processing and export. Here, we employ an in vivo nuclear export assay to show that arginine methylation is important for the nuclear export of these hnRNPs. Both Npl3p and Hrp1p fail to exit the nucleus in cells lacking Hmt1p, and overexpression of Hmt1p enhances Npl3p export. The export of a novel hnRNP-like protein, Hrb1p, which does not bind poly(A)+ RNA, however, is not affected by the lack of methylation. Furthermore, we find a genetic relationship between Hmt1p and cap-binding protein 80 (CBP80). Together, these findings establish that one biological role for arginine methylation is in facilitating the export of certain hnRNPs out of the nucleus.

Root planing following short-term pocket distention.

This study evaluated the effectiveness of root planing following short-term pocket distention. Seventy-five single-rooted teeth with probing depths > or = 5 mm and < or = 10 mm were selected. The teeth were randomly divided into three treatment groups. In groups 1 and 2 a gingival retraction cord (aluminum sulfate-impregnated in group 1 and non-impregnated cord in group 2) was packed subgingivally for 30 minutes. Following removal of the cord, the teeth were scaled and root planed. In group 3 the teeth were root planed only. Following instrumentation, the teeth were extracted and examined under a stereomicroscope. The residual calculus on the root surface of each tooth was measured using a computerized image analysis system. The quantities were compared using a two-way ANOVA and Chi-square test. The results showed that 46.3% of all root surfaces had detectable residual calculus and that the mean percentage of residual calculus per root surface was 4.41% following root planing. Forty percent of the root surfaces in group 1 had residual calculus, 38.0% in group 2, and 61.0% in group 3. There was a statistically significant difference (P < 0.01) between groups 1 and 2 compared to group 3. The mean calculus per root surface for groups 1, 2, and 3 was 3.03%, 3.04%, and 7.15%, respectively. Significant differences (P < 0.005) were found between groups 1 and 2 compared to group 3. These results indicate that subgingival calculus removal in deep pockets is enhanced with short-term pocket distention, and that there is no added benefit to having aluminum sulfate present in the retraction cord.

Treatment of intrabony defects by polylactic acid matrix barrier--a one-year follow-up study.

The present investigation was conducted to evaluate the effect of a polylactic acid-citric acid softened membrane barrier during guided tissue regeneration (GTR) surgery on human intrabony defects. Eighteen patients were treated in the study and 16 patients completed the 1-year follow-up. In all, 27 intrabony defects were treated and clinical soft tissue measurements, including probing depth (PD), probing attachment level (PAL), and recession, were recorded. Results of the investigation demonstrated a significant reduction in PD (3.7 mm), a significant gain in PAL (4.2 mm), and a slight increase in recession (1.2 mm).

Gingival overgrowth and dental alveolar alterations: possible mechanisms of cyclosporin-induced tooth migration. An experimental study in the rat.

The inter-incisal distance and dimension of the interdental papilla between the mandibular incisors were examined in cyclosporin A (CSA) fed rats over 6 weeks. Rats in the test group received CSA daily in mineral oil by gastric feeding (30 mg/kg body weight); the control group received mineral oil only. The inter-incisal distance and gingival dimensions, including bucco-lingual width and vertical height, were assessed biweekly from alginate impressed stone models. Animals were sacrificed at the end of the study and tissue sections were obtained from the anterior region of the mandible for histopathological evaluation. Both the inter-incisal distance and the dimension of the interdental papilla were significantly greater in CSA-exposed animals compared to control. The significant alteration appeared earlier in the papillary dimensions than that in the interdental distance. Particular histopathological alterations of the soft and hard tissues of the periodontium were observed in CSA-exposed animals. Within limitations of the study, we suggest that the CSA-induced gingival overgrowth may offer an active force contributing to observed tooth movement, however, remarkable alveolar remodeling should be considered as an undetermined factor for the movement.

Histometric analysis of epithelial alterations in bleeding and non-bleeding gingivae after probing and their corresponding stereomicroscopic findings of vasculature.

The present study was carried out to investigate and compare the thickness and number of rete pegs of the sulcular epithelium histometrically in bleeding and non-bleeding gingivae with special reference to comparisons of their relationship with corresponding stereomicroscopic findings. A total of 78 biopsies (40 bleeding and 38 non-bleeding gingival specimens) was obtained from 33 patients. Tissue sections with H&E stains were performed. Each gingival section was divided into three portions (coronal, middle and apical) along the gingival sulcular epithelium horizontally. The rete pegs were counted and the thickest and thinnest parts of the epithelium in three individual portions were also measured histometrically. The results show that the epithelial thickness of bleeding gingiva at the coronal and middle portions was significantly thinner than that of non-bleeding gingiva. There were also greater numbers of rete pegs of the sulcular epithelium in bleeding gingiva than of those in non-bleeding gingiva. However, there was no specific relationship between epithelial alterations of gingiva and the visibility of vasculature by stereomicroscopy. It is suggested that epithelial alterations of gingiva to some extent might be responsible for the gingival bleeding on probing clinically and highly associated with the volumetric density of underlying infiltrated connective tissue, but might not be related to the visibility of vasculature by stereomicroscopy.