Effect of Periodontal Treatment on Reducing Chronic Inflammation in Systemically Healthy Patients With Periodontal Disease.

BACKGROUND: We determined the effects and an accurate marker of periodontal treatment on serum interleukin (IL)-6 and high-sensitivity C-reactive protein (HsCRP) levels in systemically healthy individuals with periodontal disease. METHODS: This multicenter study included systemically healthy individuals with periodontal disease who received initial periodontal treatment and had no periodontal treatment history. Periodontal parameters, including periodontal inflamed surface area, masticatory efficiency, and periodontal disease classification; serum IL-6 and HsCRP levels; and serum immunoglobulin (Ig)G titers against periodontal pathogens were evaluated at baseline and after treatment. Subjects were classified as low or high responders (group) based on periodontal inflamed surface area changes. RESULTS: There were 153 participants. Only periodontal inflamed surface area changes were markedly different between low and high responders. Periodontal treatment (time point) decreased both serum IL-6 and HsCRP levels. The interaction between group and time point was remarkable only for serum IL-6 levels. Changes in serum immunoglobulin (Ig)G titers against periodontal pathogens were not associated with IL-6 changes in high responders. We analyzed the indirect effect of serum anti-Porphyromonas gingivalis type 2 IgG titer changes using mediation analysis and found no significance. However, the direct effect of group (low or high responder) on IL-6 changes was considerable. CONCLUSIONS: Periodontal treatment effectively decreased serum IL-6 levels, independent of periodontal pathogen infection, in systemically healthy individuals with periodontal disease.

Safety and Clinical Evaluation of a Sonic Tongue Brush.

BACKGROUND: Tongue coating consists of oral bacteria, desquamated epithelium, blood cells, and food residues and is involved in periodontal disease, halitosis, and aspiration pneumonia. Recently, a tongue brush with sonic vibration was developed to clean the tongue. This comparative study examined the extent of tongue coating, its effects on the tongue, bacterial count particularly on the posterior dorsum of the tongue, and the degree of pain using a manual tongue brush and the newly developed sonic tongue brush. MATERIALS AND METHODS: Patients' extent of tongue coating and the quantity of bacteria were analysed before and after brushing with a sonic or manual nylon tongue brush. Moreover, the impressions of the dorsum linguae were obtained before and after brushing to establish models that were observed under a stereo microscope to evaluate tongue trauma. Pain caused during the use of these brushes was evaluated based on the numerical rating scale (NRS). RESULTS: The extent of tongue coating and number of bacteria decreased in both the sonic and manual nylon brush groups after tongue cleaning; however, no significant differences were noted. Tongue trauma evaluation revealed that the tongue surface was significantly scratched in the manual brush group compared with the sonic brush group. NRS-based pain evaluation revealed no significant differences. CONCLUSIONS: The sonic brush was equally effective in removing tongue coating and bacteria compared with the manual brush. As the sonic brush does not cause tongue trauma, it may be considered a safe and effective cleaning tool of the tongue.

Effects of One-Stage Full-Mouth Scaling and Root Planing with Azithromycin on Diabetes and Periodontal Disease: A Randomized Controlled Trial.

Recent reports show that hemoglobin A1c (HbA1c) can be lowered by improving chronic inflammation in periodontal patients with diabetes mellitus and that full-mouth scaling and root planing (FM-SRP), in combination with azithromycin (AZM) treatment, can reduce early periodontal inflammation. However, the association of FM-SRP and AZM with periodontitis and HbA1c in patients with diabetes is largely unknown. This study investigated periodontitis and HbA1c in patients with diabetes after receiving FM-SRP and AZM to evaluate which clinical parameters most reflect the diabetic condition. Fifty-one periodontal patients with diabetes mellitus were included in this study. In total, 25 patients were assigned to the FM-SRP group in which patients were treated with FM-SRP in combination with AZM, and 26 patients were assigned to the control group in which only supragingival calculus removal was performed along with the provision of oral hygiene instructions. We evaluated periodontal parameters (probing pocket depth, periodontal inflamed surface area (PISA), bleeding on probing), and periodontal bacteria and biochemical parameters (HbA1c, high-sensitive C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1)) at baseline (BL) and 1, 3, 6, and 9 months after treatment. Compared with BL values, the FM-SRP group showed improved clinical parameters, reduced periodontal pathogens, and significantly lower HbA1c. Inflammatory cytokines (hs-CRP, TNF-α, IL-6) were significantly reduced one month after treatment and remained low thereafter. MCP-1 did not change significantly during the experimental period. PISA showed a strong correlation with HbA1c, hs-CRP, and TNF-α. FM-SRP, in combination with AZM, produced clinical, microbiological, and HbA1c improvements in periodontal patients with previously diagnosed diabetes mellitus. Additionally, PISA was shown to be a useful index for assessing the diabetic status of patients with periodontal disease.

Effect of Locally Delivered Minocycline on the Profile of Subgingival Bacterial Genera in Patients with Periodontitis: A Prospective Pilot Study.

This prospective pilot study aimed to evaluate the effect of minocycline-HCl ointment (MO), locally delivered as an adjunct to scaling and root planing (SRP), on subgingival microflora. A total of 59 periodontitis patients received SRP as an initial periodontal therapy. In the selected periodontal pockets with probing depths (PD) of 6−9 mm, the sites that exhibited a positive reaction following a bacterial test using an immunochromatographic device were subsequently treated with MO (SRP + MO group, n = 25). No additional treatment was performed at sites showing a negative reaction (SRP group, n = 34). In addition to subgingival plaque sampling, measurement of clinical parameters including PD, clinical attachment level (CAL), bleeding on probing (BOP), plaque index and gingival index (GI) were performed at baseline and 4 weeks after the initial periodontal therapy. The subgingival microflora were assessed by terminal restriction fragment-length polymorphism analysis. Relative to baseline values, the mean scores for PD-, CAL-, BOP-, and GI-sampled sites were significantly decreased post treatment in both groups (p < 0.01). The intra-comparisons showed a significant decrease in the counts of the genera Eubacterium, Parvimonas, Filifactor, Veillonella, Fusobacterium, Porphyromonas, Prevotella, and unknown species in the SRP + MO group (p < 0.05). Inter-comparisons indicated a significant decrease in the genera Veillonella in the SRP + MO group (p = 0.01). Combination therapy of SRP and local MO induced a change in the subgingival microbial community: particularly, the number of Veillonella spp. was markedly reduced.

Development and Characterization of Alkaline Phosphatase-Positive Human Umbilical Cord Perivascular Cells.

Human umbilical cord perivascular cells (HUCPVCs), harvested from human umbilical cord perivascular tissue, show potential for future use as an alternative to mesenchymal stromal cells. Here, we present the results for the characterization of the properties alkaline phosphatase-positive HUCPVCs (ALP(+)-HUCPVCs). These ALP(+)-HUCPVCs were created from HUCPVCs in this study by culturing in the presence of activated vitamin D3, an inhibitor of bone morphogenetic protein signaling and transforming growth factor-beta1 (TGF-ß1). The morphological characteristics, cell proliferation, gene expression, and mineralization-inducing ability of ALP(+)-HUCPVCs were investigated at the morphological, biological, and genetic levels. ALP(+)-HUCPVCs possess high ALP gene expression and activity in cells and a slow rate of cell growth. The morphology of ALP(+)-HUCPVCs is fibroblast-like, with an increase in actin filaments containing alpha-smooth muscle actin. In addition to ALP expression, the gene expression levels of type I collagen, osteopontin, elastin, fibrillin-1, and cluster of differentiation 90 are increased in ALP(+)-HUCPVCs. ALP(+)-HUCPVCs do not have the ability to induce mineralization nodules, which may be due to the restriction of phosphate uptake into matrix vesicles. Moreover, ALP(+)-HUCPVCs may produce anti-mineralization substances. We conclude that ALP(+)-HUCPVCs induced from HUCPVCs by a TGF-ß1 stimulation possess myofibroblast-like properties that have little mineralization-inducing ability.

Effect of Nd: YAG laser irradiation to the temporomandibular joint on taste threshold.

BACKGROUND/PURPOSE: The tissue absorption laser has been clinically applied to alleviate pain in various areas. It is used for pain relief from temporomandibular disease (TMD) in dentistry. Although the facial and trigeminal nerves are distributed around the temporomandibular joint, the effects of laser irradiation and absorption on the neural functions have not been directly studied. In this study, the Nd:YAG laser was applied to an area where the facial nerve passes with photonic radiation for the treatment of TMD. MATERIALS AND METHODS: Ten volunteers including seven males and three females were selected as subjects. Nd:YAG laser was irradiated area included several internal and external standard and associated acupuncture points. The chorda tympani nerve, a branch of facial nerve is distributed to the front two thirds of the tongue and is associated with the sense of taste. We evaluated the effect of laser irradiation and absorption on the taste function by means of an electric taste meter. RESULTS: No significant difference was identified in the values between before and after laser irradiation (Wilcoxon signed-rank test). CONCLUSION: It was confirmed that there was no effect on taste function while applying Nd:YAG laser irradiation around the TMD joint.

Effects of Antimicrobial Photodynamic Therapy on Organic Solution and Root Surface In Vitro.

Antimicrobial photodynamic therapy (a-PDT) is attracting attention as a new form of dental treatment. While it is primarily applied to produce an antibacterial effect, it decreases lipopolysaccharide (LPS) and protease activity. Here, we evaluated differences in the antibacterial activity of a-PDT on three types of bacteria and the effects on the organic substances (i.e., albumin and LPS). Furthermore, we investigated the effects of a-PDT on root surfaces. A FotoSan630® and toluidine blue were used to perform a-PDT in this study. We measured its antimicrobial activity against Porphyromonas gingivalis, Streptococcus mutans, and Enterococcus faecalis. Antimicrobial testing revealed strong antimicrobial action and P. gingivalis, E. faecalis, and S. mutans were almost undetectable after 50, 120, and 100 s, respectively. In organic resolution tests, albumin was significantly decreased from 1 min after a-PDT application onward, while LPS significantly decreased at 5 min after the application. The root surfaces after a-PDT were confirmed to be cleaner than the controls without suffering any damage. Depending on the bacterial species, a-PDT exhibited antimicrobial activity against various types of bacteria and sensitivity differed. Moreover, we reported that a-PDT resolves protein and LPS, enabling the formation of a healthy root surface without any damage.

Effects of Conditioned Medium from Bone Marrow Cells on Human Umbilical Cord Perivascular Cells.

Mesenchymal cells derived from human umbilical cord tissue are attracting increasing attention as a source for cell therapy. However, for applying the same in tissue engineering, it has been shown that the differentiation capacity of mesenchymal stromal cells (MSCs) is influenced by the tissue from which the cells are harvested. Thus, to explore the possibility of increasing the osteogenic capacity of MSCs derived from the perivascular tissue of the human umbilical cord (human umbilical cord perivascular cells, HUCPVCs), we cultured these cells using conditioned medium (CM) derived from cultures of human bone marrow-derived mesenchymal stromal cells (hBMMSCs). However, hBM-CM contains a wide variety of growth factors, the amounts and ratios of which are considered to vary with the cell culture stage. Thus, we aimed to evaluate the effects of hBM-CM derived from different stages of hBMMSC culture on the osteogenic capacity of HUCPVCs. The stages of hBMMSC culture were defined as follows: Stage 1 (mitogenic stage) represented the period from the start of hBMMSC culture to 70% cell confluence; Stage 2 (confluent stage) represented the period from 70% confluence to the initiation of calcified nodule formation; and Stage 3 (calcification stage) represented the period following the initiation of calcified nodule formation. An analysis of growth factors contained in the CM obtained at each stage by enzyme-linked immunosorbent assay showed that insulin-like growth factor 1 (IGF-1) was significantly elevated at Stage 2, whereas vascular endothelial growth factor (VEGF) was significantly elevated at Stage 3. HUCPVCs were cultured using the CM from each of the stages for 1, 2, or 3 weeks. RUNX2 expression was the most upregulated at week 1 and then downregulated in all the groups. The expression of collagen 1 was significantly elevated in Stage 2 HUCs at week 3. Alkaline phosphatase (ALP) activity, ALP, and alizarin staining were higher in Stage 2 HUCs and Stage 3 HUCs. The calcium content was the highest in Stage 2 HUCs. The calcium content of HUCPVC obtained by the method used in this study was six times higher than that reported in the previous study. Collectively, our results show that the CM obtained at Stage 2 was most effective in driving the osteogenic differentiation of HUCPVCs. Impact Statement Mesenchymal stromal cells (MSCs) derived from the perivascular tissue of umbilical cords are promising candidates for regenerative medicine. Because these are able to be differentiated into bone cells, cartilage cells, and adipocytes. The number of MSCs in perivascular tissue (HUCPVCs) is ∼1/300 but the number of HUCPVCs that differentiates into osteogenic cells is quite low. In order to promote osteogenic differentiation of HUCPVCs, we cultured HUCPVCs using conditioned medium collected from human bone marrow-derived mesenchymal stromal cells. Our study suggests that the use of conditioned medium can be effective on inducing osteogenic differentiation of HUCPVCs.

Effect of Azithromycin on Proinflammatory Cytokine Production in Gingival Fibroblasts and the Remodeling of Periodontal Tissue.

Previous reports have shown that azithromycin (AZM), a macrolide antibiotic, affects collagen synthesis and cytokine production in human gingival fibroblasts (hGFs). However, there are few reports on the effect of AZM on human periodontal ligament fibroblasts (hPLFs). In the present study, we comparatively examined the effects of AZM on hGFs and hPLFs. We monitored the reaction of AZM under lipopolysaccharide (LPS) stimulation or no stimulation in hGFs and hPLFs. Gene expression analyses of interleukin-6 (IL-6), interleukin-8 (IL-8), matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-2 (MMP-2), and Type 1 collagen were performed using reverse transcription-polymerase chain reaction (RT-PCR). Subsequently, we performed Western blotting for the analysis of the intracellular signal transduction pathway. In response to LPS stimulation, the gene expression levels of IL-6 and IL-8 in hGFs increased due to AZM in a concentration-dependent manner, and phosphorylation of nuclear factor kappa B (NF-κB) was also promoted. Additionally, AZM caused an increase in MMP-1 expression in hGFs, whereas it did not affect the expression of any of the analyzed genes in hPLFs. Our findings indicate that AZM does not affect hPLFs and acts specifically on hGFs. Thus, AZM may increase the expression of IL-6 and IL-8 under LPS stimulation to modify the inflammatory response and increase the expression of MMP-1 to promote connective tissue remodeling.

Organic resolution function and effects of platinum nanoparticles on bacteria and organic matter.

Rapid progress has been made in terms of metal nanoparticles studied in numerous fields. Metal nanoparticles have also been used in medical research, and antibacterial properties and anticancer effects have been reported. However, the underlying mechanism responsible for these effects has not been fully elucidated. Therefore, the present study focused on platinum nanoparticles (PtNPs) and examined their antibacterial properties and functional potential for decomposing organic matter, considering potential applications in the dental field. PtNPs were allowed to react with dental-related bacteria (Streptococcus mutans; Enterococcus faecalis, caries; Porphyromonas gingivalis, and endodontic and periodontal lesions). Antibacterial properties were evaluated by measuring colony formation. In addition, PtNPs were allowed to react with albumin and lipopolysaccharides (LPSs), and the functional potential to decompose organic matter was evaluated. All evaluations were performed in vitro. Colony formation in all bacterial species was completely suppressed by PtNPs at concentrations of >5 ppm. The addition of PtNPs at concentrations of >10 ppm significantly increased fragmentation and decomposition. The addition of PtNPs at concentrations of >125 pico/mL to 1 EU/mL LPS resulted in significant amounts of decomposition and elimination. The results revealed that PtNPs had antibacterial effects against dental-related bacteria and proteolytic potential to decompose proteins and LPS, an inflammatory factor associated with periodontal disease. Therefore, the use and application of PtNPs in periodontal and endodontic treatment is considered promising.

Potential function of TGF-ß isoforms in maturation-stage ameloblasts.

OBJECTIVES: To investigate potential functions of transforming growth factor-beta (TGF-ß) isoforms in maturation-stage ameloblasts during amelogenesis. METHODS: In vivo activation of TGF-ß was characterized by using matrix metalloproteinase 20 null (Mmp20-/-) and wild-type (Mmp20+/+) mice. Using mHAT9d cells cultured in the presence of each TGF-ß isoform, (1) cell proliferation was determined by MTS assay, (2) immunostaining with anti-cleaved caspase-3 monoclonal antibody was performed and apoptotic indices were measured, (3) gene expression was analyzed by RT-qPCR, and (4) the uptake of amelogenin into mHAT9d cells was directly observed using a fluorescence microscope. RESULTS: TGF-ß1 and TGF-ß3 were present in the enamel matrix of developing teeth which were activated by MMP20 in vivo. A genetic study revealed that the three TGF-ß isoforms upregulate kallikrein 4 (KLK4) mRNA levels but downregulate carbonic anhydrase II. Moreover, TGF-ß1 and TGF-ß2 significantly upregulated the mRNA level of amelotin, whereas TGF-ß3 dramatically downregulated the mRNA levels of odontogenic ameloblast-associated protein (ODAM), family with sequence similarity 83 member H (FAM83H), and alkaline phosphatase (ALP). Immunostaining analysis showed that the apoptosis of mHAT9d cells is induced by three TGF-ß isoforms, with TGF-ß3 being most effective. Both TGF-ß1 and TGF-ß3 induced endocytosis of amelogenin. CONCLUSIONS: We propose that TGF-ß is regulated in an isoform-specific manner to perform multiple biological functions such as gene expression related to the structure of basal lamina/ameloblasts, mineral ion transport, apoptosis, and endocytosis in maturation-stage ameloblasts.

The dynamics of TGF-ß in dental pulp, odontoblasts and dentin.

Transforming growth factor-beta (TGF-ß) is critical for cell proliferation and differentiation in dental pulp. Here, we show the dynamic mechanisms of TGF-ß in porcine dental pulp, odontoblasts and dentin. The mRNA of latent TGF-ß1 and TGF-ß3 is predominantly expressed in odontoblasts, whereas the mRNA expression level of latent TGF-ß2 is high in dental pulp. TGF-ß1 is a major isoform of TGF-ß, and latent TGF-ß1, synthesized in dental pulp, is primarily activated by matrix metalloproteinase 11 (MMP11). Activated TGF-ß1 enhances the mRNA expression levels of MMP20 and full-length dentin sialophosphoprotein (DSPP) in dental pulp cells, coinciding with the induction of odontoblast differentiation. Latent TGF-ß1 synthesized in odontoblasts is primarily activated by MMP2 and MMP20 in both odontoblasts and dentin. The activity level of TGF-ß1 was reduced in the dentin of MMP20 null mice, although the amount of latent TGF-ß1 expression did not change between wild-type and MMP20 null mice. TGF-ß1 activity was reduced with the degradation of DSPP-derived proteins that occurs with ageing. We propose that to exert its multiple biological functions, TGF-ß1 is involved in a complicated dynamic interaction with matrix metalloproteinases (MMPs) and/or DSPP-derived proteins present in dental pulp, odontoblasts and dentin.

Measurement accuracy of alveolar soft tissue contour using a laboratory laser scanner.

Steric analysis of morphological changes is important for evaluation of surgical techniques. This study was performed to assess the measurement accuracy of alveolar soft tissue contour with a laboratory laser scanner. The width of the maxillary alveolar soft tissue contour was evaluated in 20 volunteers. Measurement sites were established in the alveolar soft tissue contour of the maxillary incisor and canine areas. Each site was evaluated by direct measurement with a microcaliper for each subject (DMM) and image measurement using a laboratory laser scanner (IMS). The accuracy of measurement methods was evaluated. Additionally, two plaster models obtained from the same subjects were scanned and superimposed, and the nonoverlapping areas were measured. Each measurement method exhibited a strong correlation (r = 0.89). The interclass correlation coefficient (single measure) between examiners was also high for each measurement method (PMM 0.978; IMS 0.997). In the superimposed images of the two plaster models, the distance of the nonoverlapping region was only 0.06 ± 0.08 mm in the labial aspect and 0.07 ± 0.09 mm in the palatal aspect. The image measurement of the scanning data shows high accuracy in evaluation of the alveolar soft tissue contour. This technique is useful for evaluation of chronological changes in the alveolar contour after soft and hard tissue augmentation.

Effect of the Keratinized Mucosa Width on the Health Status of Periimplant and Contralateral Periodontal Tissues: A Cross-sectional Study.

INTRODUCTION: The purpose of this study was to examine whether the width of keratinized mucosa (WKM) is associated with the health status of tissue surrounding dental implants and the contralateral teeth. MATERIALS AND METHODS: Sixty patients who received implant-fixed unilateral prostheses in the premolar or molar region were recruited for the study. The following parameters were measured for each implant and contralateral tooth: WKM, gingival index (GI), probing pocket depth (PPD), bleeding on probing (BOP), pus discharge, plaque accumulation (PA), gingival recession (GR), and difficulty of brushing. The effect of the WKM on the health status of the surrounding tissue was evaluated by comparing the different WKM groups (WKM < 2 mm vs WKM ≥ 2 mm). RESULTS: Implants with a WKM <2 mm demonstrated significantly greater PPD, PA, and a higher rate of BOP compared with implants with a WKM ≥2 mm. There was significantly greater GR in contralateral teeth with a WKM <2 mm compared with a WKM ≥2 mm. In addition, implant sites had a higher rate of BOP compared with the contralateral teeth. CONCLUSIONS: Inadequate keratinized mucosa decreased cleansibility of implant sites and increased mucosal inflammation. There is a possibility that PA in implant sites caused more pronounced inflammatory response compared to contralateral tooth.

Clinical Usefulness of Novel Immunochromatographic Detection Device for Porphyromonas gingivalis in Evaluating Effects of Scaling and Root Planing and Local Antimicrobial Therapy.

BACKGROUND: The authors have previously reported development of a novel immunochromatographic device (DK13-PG-001) for specific detection of Porphyromonas gingivalis (Pg). In this study, clinical usefulness of the detection device during periodontal therapy is presented. METHODS: The multicenter study was conducted with 62 patients contributing 118 periodontitis sites with probing depth (PD) of 4 to 9 mm. Subgingival plaque samples were used for detection of Pg by DK13-PG-001 and the PCR-invader method at: 1) baseline (BL); 2) reevaluation (RE; after scaling and root planing); and 3) final evaluation (FE; after local drug delivery system). Periodontal examinations were performed concurrently with the test for Pg detection. Plasma immunoglobulin G (IgG) titers against Pg were also determined in patients using an enzyme-linked immunosorbent assay. RESULTS: DK13-PG-001 score and number of Pg by the PCR-invader method showed a strong correlation (r = 0.862) at three stages during periodontal therapy (n = 354). High sensitivity and specificity of DK13-PG-001, in comparison with the PCR-invader method, were shown. A significant correlation was found among device score, number of Pg by the PCR-invader method, and PD and clinical attachment level at BL and RE. Plasma IgG titers against Pg were significantly reduced at FE in comparison with BL. Weak but significant correlations between IgG titers and device scores were shown at BL and FE. CONCLUSION: Results suggest the DK13-PG-001 device is a useful tool for detection of Pg in dental offices and can aid clinical evaluation of the extent of periodontitis and therapeutic efficacy.

Differentiation potential of osteoblast from cultured C2C12 cells on zirconia disk.

We examined the adaptability of zirconia as a fixture for implants. A mouse myoblast cell line (C2C12) was seeded on Ce-TZP and titanium disks, and on poly-L-lysine-coated glass slides. Proliferation potency was determined by cell counting and mineral induction by BMP2 was studied. The osteoblastic differentiation potency was determined by alkaline phosphatase (ALP) and alizarin red (ARS) staining. ALP activity and calcium concentrations were colorimetrically measured. The number of cells on all materials was approximately equal. ALP and ARS staining showed densely-stained images, demonstrating the induction of C2C12 cells to express the osteoblastic phenotype. RT-PCR showed that mRNA expressions of type I collagen, osteocalcin, osterix and ALP were up-regulated. With regard to ALP activity and calcium concentration of C2C12 cells, no significant differences were observed between Ce-TZP and titanium disks. We conclude that Ce-TZP has the biological activity comparable to titanium and has the utility as fixture of dental implants.

Porcine dentin sialoprotein glycosylation and glycosaminoglycan attachments.

BACKGROUND: Dentin sialophosphoprotein (Dspp) is a multidomain, secreted protein that is critical for the formation of tooth dentin. Mutations in DSPP cause inherited dentin defects categorized as dentin dysplasia type II and dentinogenesis imperfecta type II and type III. Dentin sialoprotein (Dsp), the N-terminal domain of dentin sialophosphoprotein (Dspp), is a highly glycosylated proteoglycan, but little is known about the number, character, and attachment sites of its carbohydrate moieties. RESULTS: To identify its carbohydrate attachment sites we isolated Dsp from developing porcine molars and digested it with endoproteinase Glu-C or pronase, fractionated the digestion products, identified fractions containing glycosylated peptides using a phenol sulfuric acid assay, and characterized the glycopeptides by N-terminal sequencing, amino acid analyses, or LC/MSMS. To determine the average number of sialic acid attachments per N-glycosylation, we digested Dsp with glycopeptidase A, labeled the released N-glycosylations with 2-aminobenzoic acid, and quantified the moles of released glycosylations by comparison to labeled standards of known concentration. Sialic acid was released by sialidase digestion and quantified by measuring ß-NADH reduction of pyruvic acid, which was generated stoichiometrically from sialic acid by aldolase. To determine its forms, sialic acid released by sialidase digestion was labeled with 1,2-diamino-4,5-methyleneoxybenzene (DMB) and compared to a DMB-labeled sialic acid reference panel by RP-HPLC. To determine the composition of Dsp glycosaminoglycan (GAG) attachments, we digested Dsp with chondroitinase ABC and compared the chromotagraphic profiles of the released disaccharides to commercial standards. N-glycosylations were identified at Asn37, Asn77, Asn136, Asn155, Asn161, and Asn176. Dsp averages one sialic acid per N-glycosylation, which is always in the form of N-acetylneuraminic acid. O-glycosylations were tentatively assigned at Thr200, Thr216 and Thr316. Porcine Dsp GAG attachments were found at Ser238 and Ser250 and were comprised of chondroitin 6-sulfate and chondroitin 4-sulfate in a ratio of 7 to 3, respectively. CONCLUSIONS: The distribution of porcine Dsp posttranslational modifications indicate that porcine Dsp has an N-terminal domain with at least six N-glycosylations and a C-terminal domain with two GAG attachments and at least two O-glycosylations.

Porcine dentin sialophosphoprotein: length polymorphisms, glycosylation, phosphorylation, and stability.

Dentin sialophosphoprotein (DSPP) is critical for proper mineralization of tooth dentin, and mutations in DSPP cause inherited dentin defects. Dentin phosphoprotein (DPP) is the C-terminal cleavage product of DSPP that binds collagen and induces intrafibrillar mineralization. We isolated DPP from individual pigs and determined that its N-terminal and C-terminal domains are glycosylated and that DPP averages 155 phosphates per molecule. Porcine DPP is unstable at low pH and high temperatures, and complexing with collagen improves its stability. Surprisingly, we observed DPP size variations on SDS-PAGE for DPP isolated from individual pigs. These variations are not caused by differences in proteolytic processing or degrees of phosphorylation or glycosylation, but rather to allelic variations in Dspp. Characterization of the DPP coding region identified 4 allelic variants. Among the 4 alleles, 27 sequence variations were identified, including 16 length polymorphisms ranging from 3 to 63 nucleotides. None of the length variations shifted the reading frame, and all localized to the highly redundant region of the DPP code. The 4 alleles encode DPP domains having 551, 575, 589, or 594 amino acids and completely explain the DPP size variations. DPP length variations are polymorphic and are not associated with dentin defects.

Drug concentration in inflamed periodontal tissues after systemically administered azithromycin.

BACKGROUND: Azithromycin is an azalide antibiotic, effective against a wide range of oral bacteria including periodontopathic bacteria. Azithromycin is taken up by phagocytes and is released into inflamed tissue over time. The concentration of azithromycin in inflamed periodontal tissues over time has not been studied. In this study, we determined the azithromycin concentration in the gingiva and inflammatory connective tissue of the periodontal pocket in periodontal patients who had been administered azithromycin systemically. We also evaluated the clinical and microbiologic effects of azithromycin. METHODS: Thirty-four patients with periodontitis were prescribed azithromycin 500 mg once daily for 3 days. During the 14-day study, clinical parameters (probing depth, gingival index, bleeding on probing, and gingival crevicular fluid level) were recorded, subgingival plaque was collected for bacteriologic examination, and the azithromycin concentration in the tissues lining the periodontal pocket was measured by agar diffusion bioassay. RESULTS: Clinical parameters significantly improved after administration of azithromycin. The total number of cultivated bacteria also significantly decreased by day 4 but slightly increased after day 7. Sustained reduction in levels of six periodontopathic bacteria was not apparent until day 14. On day 7, the azithromycin concentration in the tissues lining the periodontal pockets was 50% of that on day 4, and on day 14 only 20%. CONCLUSION: Azithromycin is detectable in inflamed periodontal tissues >or=14 days after systemic administration; it is associated with clinical and microbiologic improvement.

Effects of full-mouth scaling and root planing in conjunction with systemically administered azithromycin.

BACKGROUND: One-stage full-mouth disinfection (FMD), in which full-mouth scaling and root planing (SRP) is performed with adjunctive use of chlorhexidine, was introduced in 1995. There have been several reports on the effectiveness of this treatment protocol. However, FMD was reported to induce pyrexia frequently. We examined the effects of full-mouth SRP in conjunction with azithromycin administered orally before SRP to control the number of bacteria. The purpose of this study was to compare the effects of full-mouth SRP using azithromycin with conventional SRP. METHODS: Thirty-four subjects (17 in the test group and 17 in the control group) with severe chronic periodontitis were selected. The subjects of the test group had azithromycin 3 days before full-mouth SRP. Clinical parameters (probing depth [PD], gingival index [GI], bleeding on probing [BOP], and gingival crevicular fluid [GCF]), total number of bacteria, and number of black pigment-producing rods (BPRs) were evaluated at baseline and 5, 13, and 25 weeks after baseline. RESULTS: All clinical parameters improved in the test group more than in the control group. In the bacteriologic examination, the total number of bacteria did not change during the examination. In the test group, BPRs were not detected until 13 weeks. However, BPRs were detected in the control group by 13 weeks. CONCLUSION: It was shown that full-mouth SRP using systemically administered azithromycin was a clinically and bacteriologically useful basic periodontal treatment for severe chronic periodontitis.