Root Surface Treatment Research Articles

Tetracycline at Subcytotoxic Levels Inhibits Matrix Metalloproteinase‐2 and ‐9 But Does Not Remove the Smear Layer

The antibacterial and anticollagenolytic properties of tetracycline (TCN) are valuable in periodontal therapy, and TCN treatment can remove the smear layer following root instrumentation. However, recent reports pointing to cytotoxic effects of several acids prompted this study to define TCN concentrations that are anticollagenolytic and remove the smear layer, but have low cytotoxicity. Human gingival (hGF) and periodontal ligament (hPDL) cells were treated short- (3 minutes) or long-term (24 hours) with TCN to determine concentrations yielding 50% (TD(50)) and 90% (TD(10)) cell survival. Activity assays measured TCN concentrations with half-maximal inhibition (IC(50)) of matrix metalloproteinase- 2 and -9 (MMP-2 and -9). Finally, we analyzed the effects of TCN with high (75 mg/ml) or low (1 mg/ml) cytotoxicity on the smear layer by scanning electron microscopy (SEM). The TD(50) for TCN after short-term treatment was 4 mg/ml for both hGF and hPDL. Ninety percent of the cells survived 0.2 mg/ml. With long-term treatment, the TD(50) for hGF and hPDL was 70 and 30 microg/ml, respectively, and the TD(10) was 20 and 5 microg/ml. HGF and hPDL recovered from the 3-minute treatment with 1 mg/ml, but not from concentrations exceeding 3 and 9 mg/ml, respectively. The IC(50) was 25 microg/ml for both MMP-2 and MMP-9. Whereas 75 mg/ml TCN removed the smear layer, 1 mg/ml TCN had no effects. Tetracycline has significant cytotoxicity on periodontal cells. Since non-cytotoxic concentrations of TCN inhibited MMP-2 and -9 but had no effects on the smear layer, TCN is not recommended for root surface treatment.

Use of vitamin C in delayed tooth replantation

This study evaluated microscopically the effects of root surface treatment with three different solutions in delayed rat teeth replantation. Central incisors from 30 rats (Rattus norvegicus, albinus Wistar) were extracted and left on a bench for 6 h. The pulps were extirpated and root canals were irrigated with 1% sodium hypochlorite. After endodontic treatment, the root surfaces of all teeth were submitted to a 10-min treatment with 1% sodium hypochlorite, changed every 5 min. The teeth were then rinsed with saline for 10 min and assigned to 3 groups with ten specimens each. Groups I, II and III were treated, respectively, with 2% acidulated-phosphate sodium fluoride, vitamin C solution and effervescent vitamin C (2 g, Redoxon. After root surface treatment, the teeth were filled with calcium hydroxide and replanted. The animals were sacrificed after 10 and 60 days. Group I (fluoride) presented the largest areas of replacement resorption and ankylosis. Comparing both vitamin C groups, Group III (effervescent vitamin C) yielded better results, showing more areas of ankylosis and replacement resorption than areas of inflammatory resorption.

Histologic Evaluation of Three Methods of Periodontal Root Surface Treatment in Humans

Removing subgingival plaque and calculus is a major goal of periodontal treatment. Few attempts have been made to evaluate the use of lasers for root surface debridement in periodontal therapy. The aim of the present study was to compare, histologically, the effects of hand instrumentation, ultrasonic instrumentation, and CO2 lasers on the root surfaces of teeth treated in situ. A total of 33 teeth scheduled for extraction due to severe periodontal disease were divided into three groups. In the first group, teeth were treated by ultrasonic bactericidal curettage (UBC) with an ultrasonic scaler; in the second group, teeth were treated by hand instrumentation; and in the third group, after hand instrumentation, roots were lased by a CO2 laser. The samples were then processed for histological examination. In the first and second groups, plaque and calculus were present in interradicular septa, lacunae, and surface concavities. In the third group, surfaces of specimens treated by a low-power defocused CO2 laser showed areas devoid of cementum, with completely sealed dentinal tubules, and no bacterial cell remnants. The CO2 laser treatment, used at low power and in the defocused mode, combined with traditional mechanical instrumentation, could improve root surface debridement of periodontally involved teeth. More extensive, long-term studies are needed to confirm this hypothesis.

Removal of root substance with the Vector™‐system compared with conventional debridement in vitro

The aim of the present study was to assess the removal of root substance with the Vector-system depending on different irrigation fluids and to compare the results with conventional methods for root debridement. Forty extracted human teeth were treated using four different methods: Vector-system with polishing fluid and metal curette (VP), Vector-system with abrasive fluid and metal curette (VA), conventional ultrasonic system (U) with insert tip "P" and hand instrument. Treatment of the calculus-free root surfaces was carried out for a total of 12 min. using an artificial periodontal pocket. At intervals of 120 s, the removal of dental hard tissues was assessed using a three-dimensional (3D) laser scanning device and the Match 3D software with an accuracy of 0.00001 mm(3). No difference in the removal of root substance with the hand instrument (0.0055 mm(3)/s) and the Vector-system using the abrasive fluid (0.0044 mm(3)/s) could be observed (p=0.51). Using these two systems, a larger amount of root substance (p<0.05) was removed compared with the other methods (U: 0.0023 mm(3)/s, VP: 0.0022 mm(3)/s), which did not differ from each other (p=0.76). The present study indicates that the Vector-system in combination with polishing fluid or conventional ultrasonics might be used for root debridement without extensive root substance removal.

Non‐Surgical Periodontal Therapy of Shallow Gingival Recession Defects: Evaluation of the Restorative Capacity of Marginal Gingiva After 12 Months

There is a large amount of data on surgical root coverage procedures for the treatment of gingival recessions but no controlled clinical trials on the behavior of marginal gingiva following non-surgical therapy. The aim of our study was to compare in terms of root coverage two different modalities of root surface treatment, root planing and polishing versus polishing alone, over a 12-month period. The study was conducted in a split-mouth design. Twenty-four non-smoking patients (14 females and 10 males, mean age 25.17 4.03 years) with high levels of oral hygiene (full-mouth plaque score <20%) and with two bilateral Class I buccal recessions up to 2 mm deep were selected for the study. In each patient one recession was randomly assigned to the test group and the contra-lateral one to the control group. In the test group the exposed root surface was gently debrided and polished with mini curets and mini rubber cups, while the control group was polished only. The root surface instrumentation was repeated twice a month during the first 2 months and at 2-month intervals over the next 10 months. Clinical measurements were taken at baseline and 12 months post-therapy. At baseline the mean recession depth in the test group was 1.64 +/- 0.37 mm and in the control sites 1.43 +/- 0.42 mm, which decreased at 12 months to 0.78 +/- 0.60 mm and to 1.34 +/- 0.45 mm, respectively. The difference between the two groups was significant (P <0.0001). No significant differences were observed in keratinized tissue width and probing depth improvements. The removal of microbial toxins from the exposed root surfaces by polishing prevents further progression of gingival recession; the reduction of root convexity by scaling and root planing promotes the coronal shift of the gingival margin.

Removal effects of subgingival calculus on root surface after Er:YAG laser irradiation at a high pulse rate

This aim of this study was to evaluate the clinical effectiveness of Er:YAG laser at a high pulse rate (ER-D1: HOYA continuum, Japan) for scaling of subgingival calculus and root planning. Sixty-one patients with calculus deposition were treated with the Er:YAG laser (panel setting 30–108 mJ/pulse, 30 Hz) using contact tips and the results were then subjected to clinical analysis. Clinical assessments of calculus index, pain, redness, swelling, discomfort, roughness of root surface, efficiency of scaling, PlI, PD, BOP and mobility were made prior to and at 1, 4 weeks and 3 months after treatment. Fifteen of the sixty-one patients were treated during the flap operation. The Er:YAG laser high-pulse-rate irradiation was capable of ablating the calculus on the root surface precisely and effectively. The roughness of root surface after debridement was evaluated to be adequately plane for 41 cases and still rough for 20 cases. BOP and PD were significantly improved throughout the 3-month examination of this study. No negative side effects or influences were observed on the healing of periodontal tissue following Er:YAG laser irradiation during this clinical study. In conclusion, the Er:YAG laser high-pulse-rate irradiation would be a safe and effective, alternative method for root surface treatment in both nonsurgical and surgical periodontal therapy.

Morphologic analysis, by means of scanning electron microscopy, of the effect of Er: YAG laser on root surfaces submitted to scaling and root planing

The purpose of this study was to morphologically evaluate, by means of scanning electron microscopy, the effects of Er:YAG laser on the treatment of root surfaces submitted to scaling and root planing with conventional periodontal instruments. Eighteen root surfaces (n = 18), which had been previously scaled and planed, were assigned to 3 groups (n = 6). The control Group (G1) received no further treatment; Group 2 (G2) was irradiated with Er:YAG laser (2.94 mum), with 47 mJ/10 Hz, in a focused mode with air/water spray during 15 s and with 0.57 J/cm of fluency per pulse; Group 3 (G 3) was irradiated with Er:YAG laser (2.94 mum), with 83 mJ/10 Hz, in a focused mode with air/water spray during 15 s and with 1.03 J/cm2 of fluency per pulse. We concluded that the parameters adopted for Group 3 removed the smear layer from the root surface, exposing the dentinal tubules. Although no fissures, cracks or carbonized areas were observed, an irregular surface was produced by Er:YAG laser irradiation. Thus, the biocompatibility of the irradiated root surface, within the periodontal healing process, must be assessed.

PERAWATAN KONSERVASI GIGI PADA PASIEN GOLONGAN USIA LANJUT

The need for conservative dentistry treatment for the elderly is different to the need of the other age group. Usually the main problem is root surface caries which in the future will increase in accordance with the demographic changes so that the aging population with longer retention of teeth wil also increase. Conservative treatment for the elderly especially endodontic treatment will be reviewed preceded by characteristics and treatment of root surface caries as well as the treatment of abrasion and erosion which often occur in the aging patients.

Effect of Root Surface Treatment Using EDTA on the Initial Attachment of Human Gingival Fibroblasts

Effect of Root Surface Treatment Using EDTA on the Initial Attachment of Human Gingival Fibroblasts

Morphologic changes following in vitro CO2 laser treatment of calculus‐ladened root surfaces

Background and Objective The purpose of this study was to compare morphologic changes following CO2 laser or manual curette treatment of calculus-ladened tooth root surfaces. Study Design/Materials and Methods Laser treatment consisted of repeated single passes with a 6 Watt focused beam at 20 pulses per second, a pulse length of 0.01 second, and a manufacturer's laser efficiency rating of 86% (i.e., the amount of total power delivered through the aperture). The rate of beam passage over the target surface was controlled at 4 mm/second using an 0.8 mm diameter tip. The calculated energy density was 240 J/cm2 for each pass of the beam. Scaled and root planed surfaces were treated with a standardized force of 600 grams using new curettes. Specimens were evaluated by scanning electron microscopy. Results Laser-induced surface changes included charring, meltdown and resolidification of calculus mineral, and ablation of microbial plaque. Laser-treated specimens also exhibited residual calculus and microbial plaque deposits in areas directly adjacent to the beam path. Scaled and root planed surfaces featured smooth and/or scalelike smear layers and islands of residual calculus and microbial plaque. Conclusion The rough surface topography resulting from laser treatment and residual calculus and microbial plaque deposits indicates that CO2 laser treatment of exposed root surfaces is, at best, an adjunct to traditional methods of therapy. © 1996 Wiley-Liss, Inc.

Effects of citric acid treatment on the Ca, P and Mg contents of human dental roots.

An electron microprobe analyser associated with a scanning electronic microscope was used to measure Ca, P and Mg contents of the human dental root hard tissues, before and after a citric acid treatment (pH = 1). The measurements were made on transverse sections through the cervical 1/3 of the molar roots. The measurements were performed at the following 8 levels: the internal cementum, the cementum-dentine junction, cementum-related dentine, 4 external dentine levels located at 220 microns, 420 microns, 620 microns and 820 microns from the cementum-dentine junction, and finally the juxta-pulpal dentine. After the citric acid treatment, the losses in Ca and P, but not in Mg, varied significantly with the level; an acid-resistant dentine layer of approximately 600 microns was found under the cementum-dentine junction. An increase in the Ca/P ratio was also observed in this layer. Since this external dentine zone is less demineralized by the citric acid than the underlying dentine, the collagen matrix in this region may also be less exposed. These differences in the response to citric acid that depend on the distance from the root surface may explain the unpredictability of periodontal healing after citric acid treatment of diseased root surfaces, because the amount of tissue removed during root planing is not constant.

Periodontal repair in dogs: effect of a composite graft protocol on healing in supraalveolar periodontal defects.

This study evaluated the effect of a composite graft as an adjunct to gingival flap surgery in induced chronic supraalveolar periodontal defects in the mandibular premolar region in beagle dogs. The vertical dimension of the defects, measured from the cemento-enamel junction to the alveolar bone, approximated 5 mm. Root surface treatment in quadrants receiving the graft protocol included conditioning with both critic acid and tetracycline. The composite graft (including: hydroxyapatite, freeze-dried decalcified bone, tetracycline, and fibronectin) was then fitted to the defects. Flaps were placed and sutured to cover most of the crowns of the teeth but the tips of the cusps. The root surfaces in contralateral jaw quadrants were conditioned with critic acid and the flaps similarly placed and sutured. Dogs were sacrificed 6 weeks after surgery and tissue blocks including teeth and surrounding structures processed for histometric analysis. Connective tissue repair to the root surface in teeth treated with the graft protocol approximated 60% of the defect height. Connective tissue repair in teeth treated with citric acid only was significantly greater and averaged 98% of the defect height (P less than or equal to 0.01). Cementum formation was limited following both treatments (approximately 6% of the defect height). Bone regeneration was significantly smaller in grafted sites than in sites treated with citric acid only (approximately 2% and 10% of the defect height, respectively; P less than or equal to 0.05). Root resorption was observed in almost all teeth. Ankylosis was present in two citric acid-treated specimens, both from the same dog.(ABSTRACT TRUNCATED AT 250 WORDS)

The Effect of Chlorhexidine Treatment of Root Surfaces on the Attachment of Human Gingival Fibroblasts In Vitro

Chlorhexidine mouthrinse is a widely used adjunct in periodontal therapy due to its bactericidal effects. The effect of this agent on chronic gingivitis and wound healing following surgical therapy in animals and humans has been favorable. The re-establishment of lost connective tissue attachment to the root surface following periodontal therapy is a desirable goal in which the ability of periodontal ligament fibroblasts to reattach to root surfaces of periodontally involved teeth is a critical event. Understanding the effect of chlorhexidine on fibroblast attachment will provide the rationale for its use during the healing phase of periodontal surgery. For this study, impacted third molars were sectioned into 4 pieces. Groups of 10 root pieces were exposed to 0.12% chlorhexidine or saline for 3 minutes followed by a distilled water rinse. The root pieces were incubated with human gingival fibroblasts (HGF) using standard tissue culture techniques for 1, 2, 4, 6, and 8 hours. HGF were prelabeled with 3H-thymidine to a standard specific activity. The surface area of each root piece was determined and the attached cells quantified by using scintillation spectroscopy. The number of cells per unit area was then calculated and the data expressed as cells/mm2. The repeated measures design was statistically analyzed by repeated measures analysis of variance. There was a significant difference between the number of attached cells in the chlorhexidine and the control groups (P less than 0.001). Exposure of root surfaces to chlorhexidine significantly inhibits subsequent fibroblast attachment which may interfere with regeneration of the periodontium. Hence, the data suggest that efforts should be made to minimize chlorhexidine contact with the root surface with physical barriers.

Periodontal Repair in Dogs: Effect of Root Surface Treatment With Stannous Fluoride or Citric Acid on Root Resorption

This study evaluated healing, with emphasis on root resorption, following root surface treatment with 1% aqueous stannous fluoride (SnF2), saturated citric acid (CA), or saline control (C) in conjunction with periodontal flap surgery. Supraalveolar periodontal defects were surgically created and immediately treated in the mandibular premolars in 6 beagle dogs. The defect height approximated 5 to 6 mm from the reduced alveolar bone to the cemento-enamel junction. Root treatments were rotated between experimental teeth within jaw quadrants and duplicated in left and right quadrants in the dogs. Flaps were raised to cover most of the crowns of the teeth and sutured. The dogs were sacrificed 12 weeks after surgery and tissue blocks with teeth and adjacent structures were processed for histometric analysis. SnF2-treated teeth healed with significantly longer junctional epithelium, less connective tissue repair to the root surface, and less bone regeneration than CA and C-treated teeth. New cementum formation was limited in all treatment groups. Root resorption was observed in almost all teeth exhibiting connective tissue repair, however to a lesser amount and not as frequent in SnF2 treated teeth due to limited connective tissue repair. No differences were found in amount and frequency of root resorption in CA and C-treated teeth. An inhibitory effect on root resorption of SnF2 could not be disclosed in this experiment, however, it may be concluded that CA treatment of the root surface in conjunction with reconstructive periodontal flap surgery does not seem to enhance root resorption.

Periodontal Repair in Dogs: Effect of Wound Stabilization on Healing

This study evaluated a biodegradable polylactic acid matrix as a wound stabilizing implant in reconstructive periodontal surgery. Supra-alveolar circumferential periodontal defects, 5 to 6 mm large, were surgically created around the mandibular premolars in 7 beagle dogs. The root surfaces in left and right jaw quadrants were treated with either heparin or saline. In this model, root surface treatment with heparin compromises periodontal repair and results in a long junctional epithelium and a reduced connective tissue repair to the root surface, whereas saline treatment results in almost complete connective tissue repair. Following heparin or saline treatment a polylactic acid implant was placed on 1 premolar in each quadrant. After 4 weeks of wound healing, the dogs were sacrificed and tissue blocks prepared for histometric analysis. Postoperatively, the implant became exposed and infected in 3 dogs and had to be removed. Therefore, the results reflect the 4 dogs in which healing progressed uneventfully. Connective tissue repair to the root surface in teeth treated with heparin averaged 82% of the defect height. Mean connective tissue repair in teeth treated with heparin and the implant was significantly greater and comprised approximately 99% of the defect height (P less than 0.05). Teeth treated with saline either with or without the implant also healed with almost complete connective tissue repair. The results support the importance of wound stabilization in periodontal wound healing. Development of biodegradable implant systems aimed at stabilizing and supporting the healing wound seems a desirable direction for future research in regenerative periodontal procedures.

Effect of stannous fluoride and tetracycline on repair after delayed replantation of root-planed teeth in dogs

Mandibular incisors were extracted and allowed to dry in air for 45 min. They were then root-planed extensively, leaving a cervical collar and the apical region uninstrumented, to prevent direct contact between root surface and alveolar bone after replantation while, at the same time, enabling precise and stable reseating of the tooth. Control teeth were replanted either without further treatment or after treatment with citric acid for 3 min. Experimental teeth were treated before replantation with 1% SnF2 for 5 min, 1% tetracycline HCl for 5 min, or 1% SnF2 followed by 1% tetracycline. Histometric analysis of healing in the root-planed areas showed minimal amounts of inflammatory resorption and ankylosis after 21 days in experimental teeth as compared with the control teeth. A persisting inflammatory reaction in the periodontal ligament without root resorption was, however, frequently seen. The observations confirm that the frequency of adverse healing reactions after delayed replantation of teeth from which nonvital soft tissue remnants have been removed can be reduced by demineralizing the root surface and preventing mechanical trauma to the root surface in the postoperative period. Root surface treatment with SnF2 followed by tetracycline resulted in complete absence of inflammatory resorption and ankylosis in this short-term experiment.

Effects of various root surface treatments on initial clot formation: A scanning electron microscope study.

A study was conducted to evaluate using SEM the earliest events of initial blood clot formation on periodontally diseased root surfaces given various treatments. Six teeth with periodontal disease were extracted from six different subjects and were studied in two individual groups. In the first group the root surfaces were divided into three individual treatment areas: (a) intact periodontal ligament, (b) planed, (c) planed and also treated with 1% citric acid. The root surfaces in the second group were likewise divided into three treatment areas: (a) intact periodontal ligament, (b) planed, (c) planed and topically conditioned with tetracycline HCl. All the roots were reinserted into the original extraction sites, and then removed at either "zero" (less than 5 s), one or 3 min and prepared for SEM evaluation. It was observed that organized clot formation occurred more rapidly in the treatment areas where both root planing and topical conditioning with tetracycline HCl had been done.

Total Calculus Removal: An Attainable Objective?

The primary purpose of this study was to determine if two sessions of scaling and root planing, one using a "closed" approach and the other using an "open" approach, would remove all calculus from teeth with severe periodontal disease. Fourteen teeth (8 single-rooted, 6 multi-rooted) were treated by closed scaling and root planing with an ultrasonic instrument, and 17 others (10 single-rooted, 7 multi-rooted) were treated with hand instruments. After a healing period of 4 to 8 weeks, anesthesia was secured, periodontal flaps were raised, and the teeth were treated a second time using the same instrumentation as before. The teeth were then extracted and prepared for light microscopic evaluation. Twelve of the 14 teeth treated by ultrasonics and 12 of the 17 treated by hand instruments retained calculus. The two types of instruments had similar scores in the treatment of proximal root surfaces, furcal walls, and furcal summits. Hand instrumentation appeared to be more effective than ultrasonics in removing cementum from proximal surfaces, although this is not based on a formal statistical comparison of the two methods. Neither instrument was effective in removing cementum from the furcal walls or summits. Five randomly selected blocks containing remaining root structure were deparaffinized and prepared for scanning electron microscopy. One hand-instrumented specimen, which had not shown calculus with light microscopy, displayed calculus at the SEM level. All five specimens displayed residual calculus at either the light microscope, the SEM level, or both. The results of this study indicate that complete removal of calculus from a periodontally diseases root surfaces is rare.

In-vitro formation of a new fibrous attachment to human dental roots in the presence of autologous serum.

Recent studies have accomplished the establishment of a collagenous fiber-fringe matrix upon dental root surfaces in vitro. The present study was undertaken to follow the development of such a matrix in vitro and to test the possible effects of root surface treatments upon this matrix. Periodontal ligament cells, 0.1 to 0.2-mm thick dental root discs, and alveolar bone cells were derived after extraction from four partially erupted third molars and the accompanying interradicular bony septa of 1 male patient. Autologous serum was obtained by venipuncture. Cultures were initiated by delivering a 1-ml suspension of 50,000 tritiated thymidine-labeled periodontal ligament cells and 50,000 alveolar bone cells onto each of 42 culture sets. The following day, demineralized or non-demineralized root discs treated with autologous serum, fibronectin or complete medium were placed in pairs, separated by a 0.1-1.0 mm gap, upon the initial cell layer. Representative cultures were terminated after 2, 3, 4, 5 and 6 weeks, and processed for light- and electron microscopy, morphometric analysis and autoradiography. An outstanding feature of the early cultures (2, 3 and 4 weeks) was a patchwise, random distribution of matrix making a precise developmental study impossible, although collagen fibrils were produced within the first 2 weeks. Some 3-week cultures already demonstrated a mature fiber-fringe characterized electron-microscopically as oriented, densely packed collagen fibrils closely abutting the cementum-lined root discs. The treatments (including autologous serum) used in this study had no appreciable morphologic or morphometric effect upon the fiber-fringe formed. Because none of the cultures in the present or past studies have demonstrated a true cementoid matrix, this model may not be suitable for the in-vitro study of cementum formation.

&lt;italic&gt;In Vitro&lt;/italic&gt; Interaction between Gingival Fibroblasts and Various Root Surfaces

The objective of the present in vitro study was to examine the effect of various root surface treatments on the initial attachment of gingival fibroblasts. Cultured fibroblasts were well spread and attached to demineralized dentin with citric acid, superficially curetted cementum, and root surface with periodontal ligament, while those on the planed dentin showed a poorly spread appearance. The first three root surfaces exhibited rough and irregular surface appearances with a well-developed filopodia and the latter root surface exhibited a smooth appearance, suggesting the texture of the root surface is closely associated with cell attachment. Interiorized collagen fibrils and numerous cytoplasmic vesicles were seen along the cell membrane of fibroblasts facing the root surfaces of the planed dentin, demineralized dentin, and superficially curetted cementum. Thus even the artificially exposed tooth surface with citric acid may be subjected to further alteration by fibroblasts.