Isolation and characterization of a human cementocyte-like cell line, HCY-23

Cementum is the mineralized tissue covering the tooth root that functions in tooth attachment and post-eruptive adjustment of tooth position. It has been reported to be highly similar to bone in several respects but remains poorly understood in terms of development and regeneration. Here, we investigate whether cementocytes, the residing cells in cellular cementum, have the potential to be protagonist in cementum homeostasis, responding to endocrine signals and directing local cementum metabolism. Cells from healthy erupted human teeth were isolated using sequential collagenase/EDTA digestions, and maintained in standard cell culture conditions. A cementocyte-like cell line was cloned (HCY-23, for human cementocyte clone 23), which presented a cementocyte compatible gene expression signature, including the expression of dentin matrix protein 1 ( DMP1 ), sclerostin ( SOST ), and E11/gp38/podoplanin ( E11 ). In contrast, these cells did not express the odontoblast/dentin marker dentin sialoprotein ( DSPP ). HCY-23 cells produced mineral-like nodules in vitro under differentiation conditions, and were highly responsive to inorganic phosphate (Pi). Within the limits of the present study, it can be concluded that cementocytes are phosphate-responsive cells, and have the potential do play a key role in periodontal homeostasis and regeneration33CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP304680/2014-12015/07232-0; 2015/06372-

Titanium Implants In Rabbit Femur: A Histologic Evaluation.

The success achieved by Scandinavian researchers in the development of long-term implants has stimulated many dentists to apply them worldwide. However, most of the implants did not have sufficient scientific support. The purpose of this study was to evaluate host tissue response to the insertion of an endosseous dental implant. Twenty adult New Zealand rabbits were used. Histological evaluation was prepared from the femurs. Results showed a hemorrhagic aspect and inflammatory infiltration which was subsequently substituted by granulation tissue, and later, formation of bone tissue. In the cortical bone, the presence of a necrotic area was observed which was later remodelled, and also an intense proliferation of endosteum and periosteum in the regions next to the implant, resulting in a thickening of the cortical bone surface close to the implant. Therefore, it was observed that titanium implants (Carbontec-Special Materials Ltda.) did not interfere with the bone healing process.8210511

Cigarette Smoke Inhalation Influences Bone Healing Of Post-extraction Tooth Socket: A Histometric Study In Rats

The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7th day, CSI affected negatively (p0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.233228234Evian, C.I., Rosenberg, E.S., Coslet, J.G., Corn, H., The osteogenic activity of bone removed from healing extraction sockets in humans (1982) J Periodontol, 53, pp. 81-85Meechan, J.G., McGregor, I.D., Rogers, S.N., Hobson, R.S., Bate, J.P., Dennison, M., The effect of smoking on immediate post-extraction socket filling with blood and on the incidence of painful socket (1988) Br J Oral Maxillofac Surg, 26, pp. 402-409Jones, J.K., Triplett, R.G., The relationship of cigarette smoking to impaired intraoral wound healing: A review of evidence and implications for patient care (1992) J Oral Maxillofac Surg, 50, pp. 237-240Yuhara, S., Kasagi, S., Inoue, A., Otsuka, E., Hirose, S., Hagiwara, H., Effects of nicotine on cultured cells suggest that it can influence the formation and resorption of bone (1999) Eur J Pharmacol, 383, pp. 387-393Tripton, D.A., Dabbous, M.K., Effects of nicotine on proliferation and extracellular matrix production of human gingival fibroblasts in vitro (1995) J Periodontol, 66, pp. 1056-1064Pinto, J.R., Bosco, A.F., Okamoto, T., Guerra, J.B., Piza, I.G., Effects of nicotine on the healing of extraction sockets in rats. A histological study (2002) Braz Dent J, 13, pp. 3-9Henemyre, C.L., Scales, D.K., Hokett, S.D., Cuenin, M.F., Peacock, M.E., Parker, M.H., Nicotine stimulates osteoclast resorption in a porcine marrow cell model (2003) J Periodontol, 74, pp. 1440-1446Cattaneo, V., Cetta, G., Rota, C., Vezzoni, F., Rota, M.T., Gallanti, A., Boratto, R., Poggi, P., Volatile components of cigarette smoke: Effect of acrolein and acetaldehyde on human gingival fibroblasts in vitro (2000) J Periodontol, 71, pp. 425-432Ward, K.D., Klesges, R.C., A meta-analysis of the effects of cigarette smoking on bone mineral density (2001) Calcif Tissue Int, 68, pp. 259-270Saldanha, J.B., Casati, M.Z., Neto, F.H., Sallum, E.A., Nociti Jr, F.H., Smoking may affect the alveolar process dimensions and radiographic bone density in maxillary extraction sites: A prospective study in humans (2006) J Oral Maxillofac Surg, 64, pp. 1359-1365Vanscheeuwijck, P.M., Teredesai, A., Terpstra, P.M., Verbeeck, J., Kuhl, P., Gerstenberg, B., Evaluation of the potential effects of ingredients added to cigarettes. Part 4: Subchronic inhalation toxicity (2002) Food Chem Toxicol, 40, pp. 113-131César-Neto, J.B., Duarte, P.M., Sallum, E.A., Barbieri, D., Moreno Jr, H., Nociti Jr, F.H., A comparative study on the effect of nicotine administration and cigarette smoke inhalation on bone healing around titanium implants (2003) J Periodontol, 74, pp. 1454-1459César-Neto, J.B., Benatti, B.B., Sallum, E.A., Casati, Nociti Jr, F.H., The influence of cigarette smoke inhalation and its cessation on the tooth-supporting alveolar bone: A histometric study in rats (2006) J Periodontal Res, 41, pp. 118-123César-Neto, J.B., Benatti, B.B., Sallum, E.A., Sallum, A.W., Nociti Jr, F.H., Bone filling around titanium implants may benefit from smoking cessation: A histologic study in rats (2005) J Periodontol, 76, pp. 1476-1481Benatti, B.B., César-Neto, J.B., Gonçalves, P.F., Sallum, E.A., Nociti Jr, F.H., Smoking affects the self-healing capacity of periodontal tissues. A histological study in the rat (2005) Eur J Oral Sci, 113, pp. 400-403Daftari, T.K., Whitesides Jr, T.E., Heller, J.G., Goodrich, A.C., McCarey, B.E., Hutton, W.C., Nicotine on the revascularization of bone graft. An experimental study in rabbits (1994) Spine, 19, pp. 904-911Giorgetti, A.P., Neto, J.B., Ruiz, K.G., Casati, M.Z., Sallum, E.A., Nociti Jr, F.H., Cigarette smoke inhalation modulates gene expression in sites of bone healing: A study in rats (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 110, pp. 447-452Lappin, D.F., Sherrabeh, S., Jenkins, W.M.M., McPherson, L.M.D., Effect of smoking on serum RANKL and OPG in sex, age and clinically matched supportive-therapy periodontitis patients (2007) J Clin Periodontol, 34, pp. 271-277Bandyopadhyay, A., Tsuji, K., Cox, K., Harfe, B.D., Rosen, V., Tabin, C.J., Genetic analysis of the roles of BMP2, BMP4 and BMP7 in limb patterning and skeletogenesis (2006) PLoS Genet, 2, pp. e21

Clinical Study Of Guided Bone Regeneration And/or Bone Grafts In The Treatment Of Ligature-induced Peri-implantitis Defects In Dogs.

This study evaluated, by clinical analysis, the hard tissue response following treatment of ligature-induced peri-implantitis defects in 5 dogs. The mandibular premolars were removed from both sides of the jaw. After 3 months of healing, two titanium implants were placed on each side of the mandible. Following abutment connection, 3 months later, experimental peri-implantitis was induced by the placement of cotton ligatures in a submarginal position. Ligatures and abutments were removed after one month and the bony defects were randomly assigned to one of the following treatments: debridement (DE), debridement plus guided bone regeneration (GBR), debridement plus mineralized bone graft (BG) and debridement plus guided bone regeneration associated with mineralized bone graft (GBR + BG). The peri-implant bone defects were clinically measured before and 5 months post-treatment. Results showed a higher percentage of vertical bone fill for GBR + BG (27.77 +/- 14.07) followed by GBR (21.78 +/- 16.19), BG (21.26 +/- 6.87), DE (14.03 +/- 5.6). However, there were no statistically significant differences between any of the treatments proposed (one way repeated measures analysis of variance, P = 0.265).12212713

Comparative In Vitro Study Of Root Roughness After Instrumentation With Ultrasonic And Diamond Tip Sonic Scaler

Objective: The purpose of this study was to evaluate the root surface roughness after instrumentation with hand curette and diamond-coated sonic and universal ultrasonic tips. Materials and Methods: Forty root surfaces of human teeth were randomly assigned to four treatment groups: control group (without instrumentation), curette instrumentation, ultrasonic instrumentation with universal tip and sonic instrumentation with diamond-coated tip. Each sample was instrumented with fifteen strokes. Before and after instrumentation, surface roughness was measured. In addition, the root surface topography was examined after treatment under the scanning electron microscope. Results: Significant statistical differences (p0.05). Conclusion: The diamond-coated tip with sonic scaler instrumentation and ultrasonic instrumentation produce similar root surface roughness, higher than curette instrumentation.142124129Auplish, G., Needleman, I.G., Moles, D.R., Newman, H.N., Diamond-coated sonic tips are more efficient for open debridement of molar furcations. A comparative manikin study (2000) J Clin Periodontol, 27 (5), pp. 302-307Axelsson, P., Lindhe, J., The significance of maintenance care in the treatment of periodontal disease (1981) J Clin Periodontol, 8, pp. 281-294Caffesse, R.G., Sweeney, P.L., Smith, B.A., Scaling and root planning with and without periodontal flap Surgery (1986) J Clin Periodontol, 13, pp. 205-210Chapple, I.L., Walmsley, A.D., Saxby, M.S., Moscrop, H., Effect of instrument power setting during ultrasonic scaling upon treatment outcome (1995) J Periodontol, 66 (9), pp. 756-760Copulos, T.A., Low, S.B., Walker, C.B., Trebilcock, Y.Y., Hefti, A.F., Comparative analysis between a modified ultrasonic tip and hand instruments on clinical parameters of periodontal disease (1993) J Periodontol, 64 (8), pp. 694-700Dragoo, M., A clinical evaluation of hand and ultrasonic instruments on subgigival debridment. Part I. With unmodified and modified ultrasonic inserts (1992) Int J Periodontics Restorative Dent, 12, pp. 311-323Drisko, C.L., Cochran, D.L., Blieden, T., Bouwsma, O.J., Cohen, R.E., Damoulis, P., Position paper: Sonic and ultrasonic scalers in periodontics (2000) J Periodontol, 71 (11), pp. 1792-1801. , Research, Science and Therapy Committee of the American Academy of PeriodontologyEschler, B.M., Rapley, J.W., Mechanical and chemical root preparation in vitro: Efficiency of plaque and calculus removal (1991) J Periodontol, 62 (12), pp. 755-760Flemmig, T.F., Petersilka, G.J., Mehl, A., Hickel, R., Klaiber, B., The effect of working parameters on root substance removal using a piezoelectric ultrasonic scaler in vitro (1998) J Clin Periodontol, 25 (2), pp. 158-163Jotikasthira, N.E., Lie, T., Leknes, K.N., Comparative in vitro studies of sonic, ultrasonic and reciprocating scaling instruments (1992) J Clin Periodontol, 19 (8), pp. 560-569Khatiblou, F.A., Ghodossi, A., Root surface smoothness or roughness in periodontal treatment. A clinical study (1983) J Periodontol, 54, pp. 365-367Kishida, M., Sato, S., Ito, K., Effects of a new ultrasonic scaler on.broblast attachment to root surfaces: A scanning electron microscopy analysis (2004) J Periodontal Res, 39, pp. 111-119Kocher, T., Fanghanel, J., Sawaf, H., Lits, R., Substance loss caused by scaling with different sonic scaler inserts - An in vitro study (2001) J Clin Periodontol, 28 (1), pp. 9-15Kocher, T., Gutshe, C., Plagmann, H.C., Instrumentation of furcation with modified sonic scaler inserts: Study on manikins, part I (1998) J Clin Periodontol, 25 (5), pp. 388-393Kocher, T., Plagmann, H.C., The diamond-coated sonic scaler tip. Part II: Loss of substance and alteration of root surface texture after different scaling modalities (1997) Int J Periodontics Restorative Dent, 17 (5), pp. 484-493Kocher, T., Plagmann, H.C., Root debridement of single-rooted teeth with a diamond-coated sonic scaler inserts during flap surgery - A pilot study (1999) J Clin Periodontol, 26 (4), pp. 201-205Kocher, T., Plagmann, H.C., Root debridement of molars with furcation involvement using diamond-coated sonic scaler inserts during flap surgery - A pilot study (1999) J Clin Periodontol, 26 (8), pp. 525-530Kocher, T., Tersic-Orth, Plagmann, H.C., Instrumentation of furcation with modified sonic scaler inserts: Study on manikins, part II (1998) J Clin Periodontol, 25 (6), pp. 451-456Lang, N.P., Indications and rationale for non-surgical periodontal therapy (1983) Int Dent J, 33 (2), pp. 127-136Leknes, K.N., Lie, T., Influence of polishing procedures on sonic scaling root surface roughness (1991) J Periodontol, 62, pp. 659-662Leknes, K.N., Lie, T., Boe, O.E., Selvig, K.A., A correlation study of inflammatory cell mobilization in response to subgingival microbial colonization (1997) J Periodontol, 68, pp. 67-72Leknes, K.N., Lie, T., Wikesjo, U.M., Boe, O.E., Selvig, K.A., Influence of tooth instrumentation roughness on gingival tissue reactions (1996) J Periodontol, 67 (3), pp. 197-204Leknes, K.N., Lie, T., Wikesjo, U.M., Bogle, G.C., Selvig, K.A., Influence of tooth instrumentation roughness on subgingival microbial colonization (1994) J Periodontol, 65, pp. 303-308Lie, T., Leknes, K.N., Evaluation of the effect on root surfaces of air turbine scalers and ultrasonic instrumentation (1985) J Periodontol, 56 (9), pp. 522-531Mierau, H.D., Relations between plaque formation, tooth surface roughness and self-cleaning (1984) Dtsch Zahnarztl Z, 39 (9), pp. 691-698Oberholzer, R., Rateitschak, K.H., Root cleaning or root smoothing. An in vivo study (1996) J Clin Periodontol, 23 (4), pp. 326-330Quirynen, M., Bollen, C.M., The influence of surface roughness and surface-free energy on supra- and subgingival plaque formation in man. A review of the literature (1995) J Clin Periodontol, 22 (1), pp. 1-14Rosenberg, R.M., Ash Jr., M.M., The effect of root roughness on plaque accumulation and gingival inflammation (1974) J Periodontol, 45 (3), pp. 146-150Rosling, B., Nyman, S., Lindhe, J., Jern, B., The healing potential of the periodontal tissues following different techniques of periodontal surgery in plaque-free dentitions. A 2-year clinical study (1976) J Clin Periodontol, 3 (4), pp. 233-250Schmidlin, P.R., Beuchat, M., Busslinger, A., Lehmann, B., Lutz, F., Tooth substance loss resulting from mechanical, sonic and ultrasonic root instrumentation assessed by liquid scintillation (2001) J Clin Periodontol, 28 (11), pp. 1058-106

Clinical Attachment Loss Produced By Curettes And Periodontal Files.

The aim of this study was to clinically evaluate the effect of immediate trauma from instrumentation after scaling and root planing with different instruments. Ten subjects with moderate chronic periodontitis, presenting probing depths of 3.5-6.5mm on anterior teeth, maxillary and/or mandibular, were selected. Teeth were randomly assigned to one of the following groups: PF group - scaled and planed with Hirschfeld periodontal files; CC group - scaled and planed with Gracey conventional curettes. The selected teeth were probed with a computerised electronic probe, guided by an occlusal stent and subjected to scaling and root planing. Immediately following instrumentation, teeth were probed again. The difference between relative attachment level (RAL) immediately before and after instrumentation was considered as trauma from instrumentation. Intra-group analysis revealed statistically significant differences between RAL immediately before and after instrumentation in both groups (1.28 +/- 1.13 for PF group; and 0.83 +/- 0.41 for CC group - p<0.05). However, inter-group analysis did not show statistically significant difference in trauma from instrumentation caused by the different instruments (p=0.063). Within the limits of this study, it was concluded that root instrumentation causes a mean immediate attachment loss of 1.06mm, with no differences between instrumentation with periodontal curettes or periodontal files.63768

Need Of Periodontal Treatment Evaluated With Cpitn And Its Relation To The Quality Of The Cervical Margin Of Restorations [necessidade De Tratamento Periodontal Avaliada Pelo Cpitn E Sua Relação Com A Qualidade De Acabamento Cervical Das Restaurações.]

Irregularities of the cervical margin of restorations facilitate the retention of bacterial plaque, hindering plaque control through the habitual procedures of oral hygiene and favoring the development of periodontal disease. The aim of this study was to evaluate the periodontal condition and treatment needs (applying CPITN) in relation to the cervical margin of dental restorations. Three hundred and sixty-seven teeth with class II and V cavities restored with amalgam, class III cavities restored with composite resin, cast metal restorations and unitary prostheses were examined. With a WHO periodontal probe, the position of the cervical margins of restorations was verified (supragingival, subgingival or at the gingival margin level); the presence of defects (lack or excess of restoring material) and the presence of score 2 of CPITN were also assessed. After the analysis of the data, it was possible to conclude that: 1) supragingival margins offered the best marginal adaptation and the lowest frequency of score 2; 2) both the lack and the excess of restoring material favor the development of score 2, despite the utilized material and 3) in subgingival margins, incorrect marginal adaptation was the most frequent event, mainly due to excess of restoring material, and in these cases there was higher frequency of score 2 of CPITN.151515

TiO2 nanotubes improve physico-mechanical properties of glass ionomer cement

The aim of this study was to determine the physico-mechanical properties of a high viscosity glass ionomer cement (GIC) reinforced with TiO2 nanotubes (TiO2-nt). Methods: TiO2-nt was incorporated into the GIC powder components (Ketac Molar EasyMix™) in concentrations of 0% (control group), 3%, 5%, 7% by weight. Compressive strength (n = 10/group), three point bending for flexural strength (n = 18/group), microshear bond strength to dentin and failure mode (n = 20/group), and surface roughness and weight loss before and after brushing simulation (30,000 cycles) (n = 8/group) were evaluated. Data were submitted to Shapiro-Wilk, ANOVA, Tukey and Chi-square tests (α ≤ 0.05). Results: Addition of 5% of TiO2-nt into GIC presented the highest values for compressive strength and differed from the control, 3% and 7% groups (p = 0.023). There were no significant differences in flexural strength (p = 0.107) and surface roughness before and after the dental brushing (p = 0.287) among the groups. GIC added with 5% TiO2-nt showed the lowest weight loss values (p = 0.01), whereas the control, 3% or 5% TiO2-nt groups presented similar microshear bond strength values (p ≥ 0.05). The 5% TiO2-nt group featured higher microshear bond strength than the 7% TiO2-nt group (p = 0.034). Cohesive in material was the most representative failure mode for all groups. Significance: The incorporation of TiO2-nt did not affect GIC's adhesiveness to dentin, but improved its compressive strength at 5%. Furthermore, TiO2-nt decreased the percentage of weight loss after GIC's surface wear363e85e9