Root surface texture and early cell and tissue colonization after different etching modalities

Root surface biomodification in periodontal therapy: Biological rationale and clinical applications

Regenerative periodontal therapy aims to form new cementum, periodontal ligament, and alveolar bone, all sealed by gingival tissue. The root surface acts as the wound margin during this regeneration process. Root surface biomodification (root conditioning/root decontamination), therefore, seems instrumental in promoting surface decontamination and enhancing tissue attachment by removing the smear layer, exposing collagen fibrils, and facilitating blood clot formation and stabilization. This review attempted to provide an all-encompassing, evidence-based assessment of the role of root surface biomodification in regenerative periodontal therapy, particularly in intrabony defects, furcation defects, and root coverage procedures. The reviewed evidence suggested that root conditioning agents, whether used independently or in conjunction with bone graft materials, biological agents, membranes, or connective tissue grafts, do not offer any clinical advantage regarding clinical attachment gain. Thus, integrating chemical methods with the mechanical root instrumentation process does not necessarily contribute to superior clinical outcomes.

Assessment of the Smear Layer Removal Efficacy of Three Different Agents on Periodontally Compromised Tooth: An In Vitro Study

AIM

The purpose of the present study was to evaluate the smear layer removal efficacy of three various agents on periodontally compromised tooth.

MATERIALS AND METHODS

The current study included 75 molar teeth that were extracted due to periodontal disease. After that, 25 samples were randomly assigned using a simple random technique to the three different agent groups, group A: Scaling and root planing (SRP) and application of SofScale agent, group B: SRP and application of QMix agent, group C: SRP and application of MTAD agent. Using a diamond circular saw, the treated portions were divided into horizontal and vertical halves. All samples were viewed under Scanning Electron Microscope. Every tooth was focused at the coronal third, middle third, and apical third portion with a magnification of 1000×. Data were recorded and statistically analyzed.

RESULTS

The smear layer removal efficacy was more in the QMix agent (3.06 ± 0.04) group followed by MTAD agent (3.28 ± 0.09) and SofScale agent (4.14 ± 0.10) group on the root surface. On intra group comparison, there was a statistically significant difference found in all the intra group agents with all the three levels. On inter group evaluation, at coronal third, there was no significant difference found between the different agents. There was a significant difference found between the different agents at middle and coronal third.

CONCLUSION

On conclusion, the current investigation found that, the root surfaces treated with QMix shown a greater ability to remove smear layers compared to tooth surfaces treated with MTAD and SofScale agent.

CLINICAL SIGNIFICANCE

Conventional therapies such as SRP effectively eliminate calculus, plaque, and necrosed cementum; nevertheless, they leave behind a smear layer that could impede normal healing. In an effort to overcome this, root conditioning agents were applied on the root surface to remove the smear layer. The traditional root conditioning agents such as citric acid have certain disadvantages, though, such as an acidic pH that could harm the root surface. As a result, researchers have been looking for biocompatible root conditioning treatments that are more effective. How to cite this article: Singh DK, BS Raj H, Soans CR, et al. Assessment of the Smear Layer Removal Efficacy of Three Different Agents on Periodontally Compromised Tooth: An In Vitro Study. J Contemp Dent Pract 2024;25(2):156-159.

Effect of EDTA Gel on Residual Subgingival Calculus and Biofilm: An In Vitro Pilot Study

BACKGROUND

Residual calculus, following scaling and root planing (SRP), is associated with persistent inflammation and the progression of periodontitis. This study examined the effects of a 24% neutral ethylenediaminetetraacetic acid (EDTA) gel on subgingival calculus and biofilms.

METHODS

Eleven single-rooted teeth extracted because of severe periodontal disease were randomly assigned to the following treatment groups: (1) three teeth served as untreated controls; (2) three teeth were treated by scaling and root planing (SRP) only; and (3) three teeth were treated by SRP + EDTA. The remaining two teeth, one SRP only and the other SRP + EDTA were designated for energy-dispersive X-ray spectroscopy (EDS) analysis. EDTA gel was placed on the SRP surface for 2 min and then burnished with a sterile cotton pellet.

RESULTS

SRP + EDTA treated specimens exhibited severely damaged biofilm and the disruption of the extracellular polymeric matrix. EDS scans of the smear layer and calculus featured reductions in the Weight % and Atomic % for N, F, Na, and S and increases in Mg, P, and Ca.

CONCLUSIONS

A 25% neutral EDTA gel was applied after SRP severely disrupted the residual biofilm and altered the character of dental calculus and the smear layer as shown by reductions in the Weight % and Atomic % for N, F, Na, and S and increases in Mg, P, and Ca.

A Scanning Electron Microscope Evaluation of the Adhesion of Fibrin Clot to the Periodontally Compromised Teeth after Exposed to Different Root-conditioning Agents: An In Vitro Study

AIM

The aim of this research was to assess the binding of fibrin clot to the teeth affected by periodontal disease following exposure to different root conditioning agents.

MATERIALS AND METHODS

A total of 60 human teeth with a solitary root that were subjected to extraction following severe periodontal disease were used as study samples in this research. Two analogous grooves were prepared on the proximal radicular surface of every sample employing a diamond-tapered fissure bur using an aerator handpiece beneath abundant irrigation. Every sample was assigned to one of the following groups: • Group I: Tetracycline hydrochloride solution • Group II: Ethylenediaminetetraacetic acid (EDTA) gel • Group III: Biopure MTAD™ Subsequent to conditioning, the samples were rinsed for 3 minutes with phosphate-buffered saline (PBS) and permitted to air-dry for 20 minutes. A drop of fresh human whole blood procured from a hale and hearty volunteer was coated onto the dentin blocks in all three groups. A scanning electron microscope under 5000× magnification at 15 kV was used to examine the samples. Kruskal-Wallis test and Mann-Whitney U test were performed to procure the inter- and intragroup assessments Results: The greatest fibrin clot union was noted in the EDTA gel group at 2.86 ± 0.14 in pursuit by Biopure MTAD™ group at 2.39 ± 0.08 as well as tetracycline hydrochloride solution group at 1.82 ± 0.10. A statistically significant difference was noted between the investigational groups (p < 0.001).

CONCLUSION

This research arrived at a conclusion that the dentinal surfaces subjected to conditioning with EDTA gel group as well as coated with human whole blood resulted in appreciably superior fibrin clot bonding to dentin vs Biopure MTAD™ as well as the tetracycline hydrochloride solution group.

CLINICAL SIGNIFICANCE

Connective tissue attachment subsequent to surgical procedures causing the adhesion of a fibrin clot to the radicular surface as a result of initial wound healing processes is directly related to periodontal regeneration. It depends on biocompatibility for the fibrin clot and the periodontal pathosis-affected radicular surface to stick together, which can be procured with the aid of a variety of root conditioning measures in course of periodontal treatment.

Decontamination and Biomodification of Periodontally Affected Root Surface for Successful Regeneration: Is There Room for Improvement?

Periodontitis is a multifactorial inflammatory condition associated with an oral microbiome dysbiosis that results in gingival inflammation and clinical attachment loss. Periodontal therapies are based on scaling and root planing to disturb the bacterial biofilm mechanically and remove calculus and contaminated cementum. Research does not support the use of root modifiers for decontamination and biomodification of periodontally affected root surfaces. Standardized clinical trials in large populations, assessing biological and patient-reported outcome measures, are necessary to evaluate candidate biomaterials for decontamination and biomodification of periodontally affected root surfaces.

Periodontal plastic surgery for the management of an ankylosed permanent maxillary lateral incisor: A clinical report with 5-year follow-up

Anterior maxillary tooth ankylosis disturbs the development of the alveolar bone process, leading to discrepancies between the cervical gingival margin and incisal edge position of the affected tooth, and therefore, the esthetics is compromised. Proposed treatments in adults and growing patients have been used successfully, but they have disadvantages and are contraindicated in some circumstances. This article proposes an alternative treatment for an ankylosed permanent maxillary anterior tooth with a slow replacement resorption rate in an adult patient, for whom a combination of a periodontal plastic surgery procedure and a fixed dental prosthesis was used to correct the esthetics. This treatment has less risk of complications, preserves the ankylosed tooth as long as possible, creates an optimal gingival contour, and maintains the alveolar bone for further treatment should the tooth be lost.

Dimensional evaluation of blood clot gap distances within intrabony defects following grafting and EDTA root surface treatment-experimental study in dogs

BACKGROUND

Because it is important to establish and maintain a firm blood clot to the surrounding tissues within the intrabony lesion; we have to investigate the potentials of different materials in resisting clot retraction that disrupt clot adhesion to the root surface. This study was designed to measure the gap distance created by clot retraction within the defect following intrabony defects grafting with and without root surface EDTA etching.

METHODS

Eight mongrel dogs with surgically created acute-chronic bilateral mandibular interproximal intrabony defects in the premolar-molar areas were enrolled in this study (total 8 defects per dog). Intrabony defects were divided into four groups, the first group (OFD): control open flap debridement, the second group, (EDTA treated defects) in which debridement of the defects was followed by two minute root surface etching with a neutral 24% EDTA gel followed by two minute copious saline irrigation, the third group (only grafted defects): defects received closely packed β-TCP of a particle size ranged from 150 to 500 mm, and the fourth group, (Graft + EDTA treated defects): defects were etched for 2 minutes with a neutral 24% EDTA gel and saline irrigation followed by intrabony defect fill of β-TCP. Twenty four hours post treatment, animal euthanasia was carried out for histomorphometric analysis of the tooth and root side gap distances.

RESULTS

EDTA treated group and EDTA + graft group showed statistically significant lower degree of clot shrinkage compared to both the control and only grafted group. Clot shrinkage in EDTA treated group showed no significant difference from that of the EDTA + graft group (p = 0.197). OFD and only grafted groups were found to show statistically higher clot retraction percnetage compared to both EDTA and EDTA+graft groups.

CONCLUSION

following intrabony defect debridement, blood clot undergoes clot retraction creating a micro gap with the root surface. EDTA root surface etching before graft application into the defect area significantly reduced the amount of gap distance.

The effect varied scanning electron microscopy desiccation techniques has on demineralized dentin

The study objective was to assess (a) the effect of a rubbing-application of ethylenediaminetetraacetic acid (EDTA) or citric acid (CA) has on the ultrastructure of surface dentin and (b) the effect of two scanning electron microscopy (SEM) desiccation preparation techniques have on the collagen surface produced. Treatment regions on proximal root surfaces of extracted human teeth were root planned to expose dentin. Cotton pellets soaked in either 30% CA or 24% EDTA solution were rubbed on the treatment region then processed for SEM using one of two desiccation techniques, that is, (a) critically point dried from liquid CO₂ (control) or (b) air-dried from tetramethylsilane (experimental). Specimens were coated with gold/palladium and viewed/photographed with an SEM. Specimens of the control groups displayed tufted fibrils (CA > EDTA) with many dentin tubules being partially obscured by overhanging fibrils. Air-dried specimens of both treatment groups displayed a flat intact monolayer devoid of a matted meshwork of fibrous collagen. Discrete fibril "sprigs," emanating from the surface monolayer, were characteristic of the EDTA group only. The rubbing-application of EDTA on dentin produces a tufted fibril surface somewhat similar to that produced by CA. Air-drying desiccation of both resulted in marked distortion with fibril collapse/coalescence of the tufted collagen matrix.

A Comparative Scanning Electron Microscopic Analysis of the Effect of QMix® and SofScale™ as an Adjunct to Scaling and Root Planing on Periodontally Compromised Root Surfaces: An In vitro Study

Aim:

This study aimed to comparatively analyze, under scanning electron microscope (SEM), the effect of the use of QMix^® and SofScale^™ as an adjunct to scaling and root planing (SRP) on periodontally compromised root surfaces.

Settings and Design:

This study was carried out in K. M. Shah Dental College and Hospital, Vadodara.

Methodology:

This was a single-blinded in vitro study which compared QMix^® and SofScale^™ as an adjunct to SRP on periodontally compromised root surfaces under SEM.

Statistical Analysis Used:

Statistical analysis was done using a nonparametric Mann–Whitney U-test to test the null hypothesis that there is no difference between the test and control groups.

Results:

The sum of ranks for QMix^® was 306.50 and the sum of ranks for SofScale^™ was 513.50. The group which was treated with QMix^® showed statistically significant results (P = 0.004) as compared to group which was treated with SofScale^™.

Conclusion:

Comparative analysis showed that QMix^® had significantly better smear layer removal ability as compared to SofScale^™. However, uniform root surface was achieved with both QMix^® and SofScale^™.

An in vitro scanning electron microscope study to evaluate the efficacy of various root conditioning agents

AIM

The purpose of present study was to investigate the scanning electron microscopic alterations produced on scaled and root planed dentin surfaces after application of different etching modalities namely citric acid, tetracycline hydrochloride and ethylenediaminetetraacetic acid (EDTA).

MATERIALS AND METHODS

Eighty specimens of teeth were collected and categorized into four groups. In group 1, control group specimens were treated with normal saline for 3 min, group 2 specimens were treated with citric acid, group 3 specimens were treated with tetracycline hydrochloride for 3 min and group 4 specimens were treated with 15% EDTA.

RESULTS

Opening of dentinal tubules was seen in all specimens except for control group that was treated with normal saline. The total number of tubules seen was highest in citric acid group as compared to tetracycline hydrochloride and EDTA Group. The total number of patent tubule opening was highest in citric acid as compared to EDTA and tetracycline. The diameter of patent dentinal tubules in citric acid group was more than EDTA and tetracycline.

CONCLUSION

The study showed that all the three agents were effective in removing the smear layer however number of patent and wider diameter dentinal tubules was seen in vitro best in citric acid than EDTA and then in tetracycline hydrochloride. Hence, citric acid group is more efficient than EDTA and tetracycline HCl group in removing the smear layer and in opening of number of patent dentinal tubules.

Evaluation of different irrigating solutions on smear layer removal of primary root dentin

AIM

To evaluate the efficacy of ethanolic extract of Salvadora persica (S. persica) and BioPure MTAD (a mixture of a tetracycline isomer, an acid, and a detergent) in removing the intracanal smear layer of primary teeth.

MATERIALS AND METHODS

The root canal of 40 extracted human primary anterior teeth were cleaned, shaped and grouped into experimental (n = 30) and control (n = 10). The root canals of the positive (n = 5) and the negative control (n = 5) were irrigated for 3 minutes with 5 ml of 17% ethylenediaminetetraacetic acid (EDTA) or saline respectively. The canals in the experimental groups were irrigated for 3 minutes with 5 ml of 1 mg/ml ethanolic extract of S. persica (n = 15) or BioPure MTAD (n = 15) and then flushed with 2 ml of saline. The presence or absence of smear layer at the coronal and middle portion of each canal were examined under a scanning electron microscope (SEM).

RESULTS

A significant difference (p = 0.004) in smear layer removal between S. persica and MTAD at the middle third of the canal was observed. MTAD solution was as effective as 17% EDTA in removing the smear layer.

CONCLUSION

MTAD was significantly more effective in smear layer removal than S. persica solution at the middle third of the canal wall.

CLINICAL SIGNIFICANCE

Both tested irrigant solutions have the ability to remove the intracanal smear from primary root dentin following cleaning and shaping of the root canal and could be an alternative to EDTA.

Combination of Root Surface Modification with BMP-2 and Collagen Hydrogel Scaffold Implantation for Periodontal Healing in Beagle Dogs

Objective : Biomodification of the root surface plays a major role in periodontal wound healing. Root surface modification with bone morphogenetic protein (BMP) stimulates bone and cementum-like tissue formation; however, severe ankylosis is simultaneously observed. Bio-safe collagen hydrogel scaffolds may therefore be useful for supplying periodontal ligament cells and preventing ankylosis. We examined the effects of BMP modification in conjunction with collagen hydrogel scaffold implantation on periodontal wound healing in dogs. Material and Methods: The collagen hydrogel scaffold was composed of type I collagen sponge and collagen hydrogel. One-wall infrabony defects (5 mm in depth, 3 mm in width) were surgically created in six beagle dogs. In the BMP/Col group, BMP-2 was applied to the root surface (loading dose; 1 µg/µl), and the defects were filled with collagen hydrogel scaffold. In the BMP or Col group, BMP-2 coating or scaffold implantation was performed. Histometric parameters were evaluated at 4 weeks after surgery. Results: Single use of BMP stimulated formation of alveolar bone and ankylosis. In contrast, the BMP/Col group frequently enhanced reconstruction of periodontal attachment including cementum-like tissue, periodontal ligament and alveolar bone. The amount of new periodontal ligament in the BMP/Col group was significantly greater when compared to all other groups. In addition, ankylosis was rarely observed in the BMP/Col group. Conclusion: The combination method using root surface modification with BMP and collagen hydrogel scaffold implantation facilitated the reestablishment of periodontal attachment. BMP-related ankylosis was suppressed by implantation of collagen hydrogel.

Root Surface Bio-modification with Erbium Lasers- A Myth or a Reality??

The objective of this literature review was to critically review the evidence available in the literature regarding the expediency of erbium family of lasers for root bio modification as a part of periodontal therapy. The literature search was performed on the Pubmed using MeSH words such as "lasers/therapeutic use, scaling, dental calculus, tooth root/anatomy and histology, ultrasonic therapy". The studies were screened and were grouped as follows: those evaluating a) efficacy for calculus removal with the Erbium family of laser b) root surface changes following Er YAG and Er Cr YSGG application c) comparative studies of the Er YAG, Er Cr YSGG lasers versus conventional methods of root surface modification d) Bio compatibility of root surface following Erbium laser treatment e) Studies on the combined efficacy of laser root modification with conventional methods towards root surface bio-modification f) Studies on effectiveness of root surface bio-modification prior to root coverage procedures. In conclusion, the erbium family has a proven anti-bacterial action, predictable calculus removal, minimal root substance removal, and appears to favor cell attachment. The Erbium family of lasers appears to be a useful adjunct for the management of periodontal disease.

Anti-infective therapy with an Er:YAG laser: influence on peri-implant healing

In addition to conventional treatment modalities (mechanical and chemical), the use of lasers has been increasingly proposed for the treatment of periodontal and peri-implant infections (i.e., cleaning and detoxification of implant surfaces). Preliminary results from basic studies have pointed to the high potential of the Erbium-doped: Yttrium, Aluminum and Garnet (Er:YAG) laser. Furthermore, preliminary clinical data indicate that treatment with this kind of laser may positively influence peri-implant healing. The aim of this research update is to evaluate, based on the currently available evidence, the use of an Er:YAG laser for the treatment of peri-implant infections and to indicate its potential as a new treatment modality.

Early root surface colonization by human periodontal ligament fibroblasts following treatment with different biomaterials

OBJECTIVES

The present in-vitro study examined the effects of different biomaterials on early root surface colonization by human periodontal ligament (PDL) fibroblasts using confocal-laser-scanning-microscopy (CLSM).

MATERIALS AND METHODS

Fifteen periodontally-diseased teeth were extracted, treated with scaling/root planing and longitudinally cut to obtain 30 root fragments. Fragments were treated either with 24% EDTA following application of enamel matrix derivative (EMD), 24% EDTA or EMD only, nanocrystalline hydroxyapatite (NHA) paste or oily calcium hydroxide suspension (OCHS) for 1 h each. The analogue untreated root specimens served as controls. Root fragments were incubated with human PDL fibroblasts and cellular proliferation and morphology were evaluated after 1, 3, 5 and 8 days using CLSM-visualization and image recognition software.

RESULTS

The rate of cellular proliferation was different among treatment modalities examined (p = 0.019). Except treatment with NHA paste all treatment modalities improved cellular proliferation on root surfaces at all different points of time compared with the control specimens. A significant difference between treatment modalities was observed between EMD and NHA paste (p = 0.008). No synergistic effect could be demonstrated comparing root surface conditioning with 24% EDTA and EMD application compared to 24% EDTA or EMD application only.

CONCLUSION

The present results suggest that initial root surface colonization by PDL fibroblasts may be enhanced by root surface conditioning with 24% EDTA and application of EMD, application of 24% EDTA or EMD alone and OCHS. The addition of 24% EDTA for root surface conditioning prior to EMD application provided no synergistic effects in terms of early root surface colonization by PDL fibroblasts.

Effect of the association between citric acid and EDTA on root surface etching

OBJECTIVE

This study aims to compare the clot stabilization on root surfaces conditioned with citric acid and ethylenediamine-tetraacetic acid (EDTA).

MATERIALS AND METHODS

Scaled root samples (n = 100) were set in fve groups: group I-control group (saline solution); group II (24% EDTA); group III (25% citric acid); group IV (EDTA + citric acid); group V (citric acid + EDTA). Fifty samples were assessed using the root surface modifcation index (RSMI). The other 50 received a blood drop after conditioning. Clot formation was assessed using blood elements adhesion index (BEAI). A blind examiner evaluated photomicrographs. Statistical analysis considered p < 0.05.

RESULTS

Groups-III and G-V attained the best results for RSMI and BEAI in comparison to control. The worst results for clot stabilization were seen in group-II. EDTA employment before citric acid (group-IV) reduced clot formation in comparison to citric acid use alone (group-III).

CONCLUSION

Root conditioning with citric acid alone and before EDTA had the best results for smear layer removal and clot stabilization. EDTA inhibited clot stabilization on root surface and must have a residual activity once it has diminished clot adhesion to root even after citric acid conditioning. Thus, EDTA can be used to neutralize citric acid effects on periodontal cells without affecting clot stabilization. Clinical signifcance: To demonstrate that citric acid use on root surfaces previously affected by periodontal disease may favor clot stabilization and may have a benefcial effect on surgical outcomes. Also, EDTA can be used to neutralize citric acid effects on periodontal cells.

Comparação in vitro da eficácia de diferentes formulações do gel de EDTA 24% no condicionamento da superfície radicular

INTRODUÇÃO: A biomodificação radicular visa a alterar a superfície radicular para auxiliar no reparo das estruturas periodontais de suporte destruídas pela doença periodontal. OBJETIVO: Avaliar por meio de microscopia eletrônica de varredura a eficácia do condicionamento químico com gel de EDTA 24% na remoção de smear layer e na exposição de fibras colágenas, verificando-se diferentes marcas comerciais, modos e tempos de aplicação. MATERIAL E MÉTODO: Um total de 225 amostras foram obtidas e distribuídas aleatoriamente em cinco grupos: soro fisiológico (controle); EDTA 24% (Farmácia Santa Paula); EDTA-T 24% (Farmácia Santa Paula); EDTA 24% (PrefGel; Straumann); EDTA 24% (Biodinâmica). As amostras de cada grupo foram redistribuídas aleatoriamente em subgrupos (n = 5) e condicionadas com os diferentes géis de EDTA nos tempos de 1, 2 e 3 minutos, e nos modos de aplicação tópica, fricção vigorosa e fricção suave. Os testes de Kruskal-Wallis e Dunn (p < 0,05) foram utilizados e aplicados separadamente para os fatores: marca comercial, tempo e modo de aplicação. RESULTADO: A análise estatística revelou que o gel de EDTA 24% da Biodinâmica promoveu a menor remoção de smear layer. Não foram detectadas diferenças estatísticas para os tempos de aplicação. O modo de aplicação fricção suave resultou em menor quantidade de smear layer residual. CONCLUSÃO: Todos os géis de EDTA 24% utilizados foram eficazes na remoção de smear layer e na exposição de fibras colágenas, independentemente do tempo de aplicação; no entanto, o modo de fricção suave foi mais efetivo. Na análise comparativa entre os produtos, o EDTA da Biodinâmica foi menos efetivo, já que promoveu menor remoção de smear layer e exposição de fibras colágenas.

EDTA-S: A novel root conditioning agent

BACKGROUND

To evaluate the efficacy of 15% ethylenediaminetetraacetic acid (EDTA)-S (EDTA with soft soap) preparation for the removal of smear layer at human root surfaces.

MATERIALS AND METHODS

Twenty teeth indicated for extraction due to periodontal disease were sectioned using high speed cylindrical bur under copious irrigation. The root surfaces were instrumented with Gracey 7-8 curette (Hu-Friedy), 12 times to induce an "experimental smear layer". Following root planning, the root surface was cut using diamond disc and separated from the crown. Samples were randomly distributed into five groups. One group was control, saline and test groups were EDTA 15% alone, by active and passive applications (groups 2 and 3), and EDTA 15%+soft soap, by active and passive applications (groups 4 and 5). Specimens were then subjected to scanning electron microscope study. Smear layer removal was evaluated according to Sampaio et al., index.

RESULTS

EDTA-S removed the smear layer better than plain EDTA and the control group, while active application of the root conditioning agent had significant difference than the passive application of the agent.

CONCLUSION

EDTA-S has favorable benefits over EDTA alone, and active application is better in comparison with passive application of root conditioning agent.

CLINICAL RELEVANCE

Removal of smear layer has been considered as an important step in periodontal regenerative therapy. Scaling and root planning alone with saline irrigation does not remove the smear layer. EDTA is a commonly used root conditioning agent in periodontal therapy. The addition of a detergent to EDTA proved to remove smear layer more efficiently than EDTA alone.

Comparison of fibrin clot adhesion to dentine conditioned with citric acid, tetracycline, and ethylene diamine tetra acetic acid: An in vitro scanning electron microscopic study

AIM

The purpose of this study was to evaluate and compare the root surface changes subsequent to the application of citric acid, tetracycline, Ethylenediaminetetraacetic acid (EDTA), and the combination of citric acid and tetracycline, and its influence on the adhesion of a fibrin clot with and without mild disruptive forces.

MATERIALS AND METHODS

A total of 100 periodontally diseased root specimens were grouped into Saline (control Group I), 24% EDTA gel (Group-II), Citric acid (Group-III), Tetracycline (Group IV), and Citric acid + tetracycline (Group V) treatment groups containing 20 in each. After root conditioning, fresh human blood was applied to each root specimen and was allowed to clot. Ten specimens in each group were rinsed in phosphate-buffered saline and designated as 'Non-agitated'. The remaining ten specimens from each group were rinsed in phosphate-buffered saline on a rotary shaker and designated as 'Agitated'. The roots were processed for scanning electron microscopy (SEM) to assess and compare the clot adhesion on them. The scores were compared through standard statistical packages.

RESULTS

The highest mean blood clot adhesion score was observed in roots treated with a combination of citric acid and tetracycline, whereas, the least score was observed in roots treated with saline.

CONCLUSION

The root specimens treated with the combination of citric acid and tetracycline as well as citric acid alone, best supported the fibrin clot. Tetracycline alone appeared to be less effective in supporting the clot. EDTA gel of 24% was least effective to promote the adhesion of a fibrin clot.

The efficacy of Salvadora persica extract in the elimination of the intracanal smear layer: A SEM study

AIM

To evaluate the efficacy of an ethanolic Salvadora persica extract in removing the smear layer following a root canal procedure.

METHODS

Sixty extracted, single-rooted human teeth were cleaned, shaped, and divided into four groups. Experimental groups 1 (n = 20) and 2 (n = 20) were irrigated with 1 mg/ml and 5 mg/ml of S. persica, respectively. The positive controls (n = 10) were irrigated with 17% ethylenediaminetetraacetic acid (EDTA), while the negative controls (n = 10) were irrigated with saline. Approximately 5 ml of the irrigating solution was delivered into the root canals for 5 min, and the final rinse was performed with 5 ml of 1% sodium hypochlorite. Scanning electron microscopy was used to evaluate the endodontic smear layer removal at the coronal, middle, and apical thirds of the specimens.

RESULTS

A significant difference in smear layer removal between groups 1 and 2 at the coronal and middle thirds of the canal was observed, and no significant difference was seen between group 2 and the positive control at the coronal third. At the apical third, both concentrations of S. persica had similar effects and were less effective than the positive control in removing the smear layer.

CONCLUSION

The 5 mg/ml S. persica solution was significantly more effective than the 1 mg/ml solution. In addition, the 5 mg/ml S. persica solution was as effective as 17% EDTA in removing the smear layer from the coronal third of the canal wall.

Comparison among four commonly used demineralizing agents for root conditioning: a scanning electron microscopy

Dental roots that have been exposed to the oral cavity and periodontal pocket environment present superficial changes, which can prevent connective tissue reattachment. Demineralizing agents have been used as an adjunct to the periodontal treatment aiming at restoring the biocompatibility of roots.

OBJECTIVE

This study compared four commonly used demineralizing agents for their capacity of removing smear layer and opening dentin tubules.

METHODS

Fifty fragments of human dental roots previously exposed to periodontal disease were scaled and randomly divided into the following groups of treatment: 1) CA: demineralization with citric acid for 3 min; 2) TC-HCl: demineralization with tetracycline-HCl for 3 min; 3) EDTA: demineralization with EDTA for 3 min; 4) PA: demineralization with 37% phosphoric acid for 3 min; 5) CONTROL: rubbing of saline solution for 3 min. Scanning electron microscopy was used to check for the presence of residual smear layer and for measuring the number and area of exposed dentin tubules.

RESULTS

Smear layer was present in 100% of the specimens from the groups PA and control; in 80% from EDTA group; in 33.3% from TC-HCl group and 0% from CA group. The mean numbers of exposed dentin tubules in a standardized area were: TC-HCl=43.8±25.2; CA=39.3±37; PA=12.1±16.3; EDTA=4.4±7.5 and CONTROL=2.3±5.7. The comparison showed significant differences between the following pairs of groups: TC-HCl and CONTROL; TC-HCl and EDTA; CA and CONTROL; and CA and EDTA. The mean percentages of area occupied by exposed dentin tubules were: CA=0.12±0.17%; TC-HCl=0.08±0.06%; PA=0.03±0.05%; EDTA=0.01±0.01% and CONTROL=0±0%. The CA group differed significantly from the others except for the TC-HCl group.

CONCLUSION

There was a decreasing ability for smear layer removal and dentin tubule widening as follows: AC>TC-HCl>PA>EDTA. This information can be of value as an extra parameter for choosing one of them for root conditioning.

Ultramorphology of the root surface subsequent to hand-ultrasonic simultaneous instrumentation during non-surgical periodontal treatments: an in vitro study

Objective

The purpose of this study was to investigate the ultramorphology of the root surfaces induced by mechanical instrumentation performed using conventional curettes or piezoelectric scalers when used single-handedly or with a combined technique.

Material and Methods

Thirty single-rooted teeth were selected and divided into 3 groups: Group A, instrumentation with curettes; Group B instrumentation with titanium nitride coated periodontal tip mounted in a piezoelectric handpiece; Group C, combined technique with curette/ultrasonic piezoelectric instrumentation. The specimens were processed and analyzed using confocal and scanning electron microscopy. Differences between the different groups of instrumentation were determined using Pearson’s χ ² with significance predetermined at α=0.001.

Results

Periodontal scaling and root planing performed with curettes, ultrasonic or combined instrumentation induced several morphological changes on the root surface. The curettes produced a compact and thick multilayered smear layer, while the morphology of the root surfaces after ultrasonic scaler treatment appeared irregular with few grooves and a thin smear layer. The combination of curette/ultrasonic instrumentation showed exposed root dentin tubules with a surface morphology characterized by the presence of very few grooves and slender remnants of smear layer which only partially covered the root dentin. In some cases, it was also possible to observe areas with exposed collagen fibrils.

Conclusion

The curette-ultrasonic simultaneous instrumentation may combine the beneficial effects of each instrument in a single technique creating a root surface relatively free from the physical barrier of smear layer and dentin tubules orifices partial occlusion.

Biological effects of a root conditioning agent for dentin surface modification in vitro

Purpose

Connective tissue reattachment to periodontally damaged root surfaces is one of the most important goals of periodontal therapy. The aim of this study was to develop a root conditioning agent that can demineralize and detoxify the infected root surface.

Methods

Dentin slices obtained from human teeth were treated with a novel root planing agent for 2 minutes and then washed with phosphate-buffered saline. Smear layer removal and type I collagen exposure were observed by scanning electron microscopy (SEM) and type I collagen immunostaining, respectively. Cell attachment and lipopolysaccharides (LPS) removal demonstrated the efficiency of the root conditioning agent.

Results

SEM revealed that the smear layer was entirely removed and the dentinal tubules were opened by the experimental gel. Type I collagen was exposed on the surfaces of the dentin slices treated by the experimental gel, which were compared with dentin treated with other root planing agents. Dentin slices treated with the experimental gel showed the highest number of attached fibroblasts and flattened cell morphology. The agar diffusion assay demonstrated that the experimental gel also has effective antimicrobial activity. Escherichia coli LPS were effectively removed from well plates by the experimental gel.

Conclusions

These results demonstrated that this experimental gel is a useful tool for root conditioning of infected root surfaces and can also be applied for detoxification of ailing implant surface threads.

A scanning electron microscopy study of diseased root surfaces conditioned with EDTA gel plus Cetavlon after scaling and root planing

In the present investigation, a scanning electron microscopy analysis was performed to evaluate the effects of the topical application of ethylenediaminetetraacetic acid (EDTA) gel associated with Cetavlon (EDTAC) in removing the smear layer and exposing collagen fibers following root surface instrumentation. Twenty-eight teeth from adult humans, single rooted and scheduled for extraction due to periodontal reasons, were selected. Each tooth was submitted to manual (scaling and root planing) instrumentation alone or combined with ultrasonic instruments, with or without etching using a 24% EDTAC gel. Following extraction, specimens were processed and examined under a scanning electron microscope. A comparative morphological semi-quantitative analysis was performed; the intensity of the smear layer and the decalcification of cementum and dentinal surfaces were graded in 12 sets using an arbitrary scale ranging from 1 (area covered by a smear layer) to 4 (no smear layer). Root debridement with hand instruments alone or combined with ultrasonic instruments resulted in a similar smear layer covering the root surfaces. The smear layer was successfully removed from the surfaces treated with EDTAC, which exhibited numerous exposed dentinal tubules and collagen fibers. This study supports the hypothesis that manual instrumentation alone or instrumentation combined with ultrasonic instrumentation is unable to remove the smear layer, whereas the subsequent topical application of EDTAC gel effectively removes the smear layer, uncovers dentinal openings and exposes collagen fibers.

Effects of basic fibroblast growth factor on density and morphology of fibroblasts grown on root surfaces with or without conditioning with tetracycline or EDTA

A study was conducted to evaluate in vitro the effect of root surface conditioning with basic fibroblast growth factor (b-FGF) on morphology and proliferation of fibroblasts. Three experimental groups were used: non-treated, and treated with 50 microg or 125 microg b-FGF/ml. The dentin samples in each group were divided into subgroups according to the chemical treatment received before application of b-FGF: none, or conditioned with tetracycline-HCl or EDTA. After contact with b-FGF for 5 min, the samples were incubated for 24 h with 1 ml of culture medium containing 1 x 10(5) cells/ml plus 1 ml of culture medium alone. The samples were then subjected to routine preparation for SEM, and random fields were photographed. Three calibrated and blind examiners performed the assessment of morphology and density according to two index systems. Classification and regression trees indicated that the root surfaces treated with 125 microg b-FGF and previously conditioned with tetracycline-HCl or EDTA presented a morphology more suggestive of cellular adhesion and viability (P = 0.004). The density of fibroblasts on samples previously conditioned with EDTA, regardless of treatment with b-FGF, was significantly higher than in the other groups (P < 0.001). The present findings suggest that topical application of b-FGF has a positive influence on both the density and morphology of fibroblasts.

Comparison of operative procedure variables on pulpal viability in an ex vivo model

AIM

To measure and compare the responses of pulp tissue to cavity preparation and restoration variables using a novel tooth slice culture model.

METHODOLOGY

Experimental cavities (265) were continuously cut, under carefully controlled conditions, into the dentine of the labial aspect of 28-day-old Wistar rat incisors, and slices of these teeth maintained in organ culture for up to 2 weeks. The experimental variables examined were: the preparation method, remaining dentine thickness, coolant, drill speed, conditioning with EDTA and filling materials. The reactions of the dentine-pulp complex to the experimental variables were measured using pathohistometric analysis and the correlations between variables were determined using analysis of variance statistical tests.

RESULTS

In rank order of surgically induced restorative pulpal injury, from the most to the least injurious were: remaining dentine thickness, absence of coolant during cavity preparation, bur speed, cavity conditioning treatments and the filling material.

CONCLUSIONS

To reduce pulp injury and to promote pulpal repair activity, the correct use of appropriate materials are important. However, of relatively greater importance is the operative technique adopted, the need to avoid the excess removal of dentine and to minimize trauma during preparation.

Histological analysis of effects of 24% EDTA gel for nonsurgical treatment of periodontal tissues

The aim of this study was to investigate, by means of histological and histomorphometric analysis, the effects of 24% ethylenediaminetetraacetic acid (EDTA) gel in periodontal tissue when used in combination with conventional periodontal treatment. Periodontitis was induced in the 2nd upper left permanent molars of 45 male Wistar rats by means of ligature. After 5 weeks, this was removed and debridement was performed. The animals were then randomly divided into 3 groups; group 1: mechanical treatment, group 2: mechanical treatment and EDTA gel application for 2 min, and group 3: mechanical treatment and placebo gel application for 2 min. After the treatment, rinsing was done with 0.9% saline solution for 1 min in all cases, followed by root notching in the deepest part of the pocket. After 4, 10, and 28 days the animals were sacrificed. The averages obtained were evaluated by means of test two-way analysis of variance (ANOVA) and Tukey statistical tests (P < 0.05). The results showed that with respect to the type of treatment employed, there were no statistically significant differences in the vitality of the periodontal tissue. It was concluded that 24% EDTA gel did not interfere with periodontal tissue repair when used in combination with conventional periodontal treatment.

Effect of Er:YAG Laser Combined With rhPDGF-BB on Attachment of Cultured Fibroblasts to Periodontally Involved Root Surfaces

BACKGROUND

The use of the erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser in periodontal therapy has been the focus of much research. Recombinant human platelet-derived growth factor-BB (rhPDGF-BB) is suggested as a potent stimulator and strong mitogen for human periodontal ligament cells. The present study tested the direct effects of Er:YAG laser irradiation, alone or with rhPDGF-BB application, on the biocompatibility of periodontally diseased roots through fibroblast attachment and proliferation.

METHODS

The study examined five healthy and 15 periodontally involved teeth, prepared from proximal surfaces, which were divided randomly into four groups (10 specimens each): group 1: healthy; group 2: untreated diseased; group 3: Er:YAG laser irradiation (60 mJ/pulse, 10 Hz); and group 4: Er:YAG laser irradiation (60 mJ/pulse, 10 Hz) plus rhPDGF-BB application (50 ng/ml). Three subgroups per group (three specimens each) were incubated for three periods (1, 3, or 7 days). The remaining specimen was used to determine surface topography. Fibroblasts were pooled on root specimens and incubated. Results were evaluated using scanning electron microscopy. Repeated cell counts were performed within a representative standard area.

RESULTS

Using paired t tests, all experimental groups (except group 2 diseased) showed statistically significant differences between 1- and 3-day and between 1- and 7-day incubation periods, but not between 3- and 7-day incubation periods. Using analysis of variance, the intergroup comparison showed significant differences favoring group 1 over groups 2 and 3 and group 4 over group 2 at the 1-day incubation period; group 1 was favored over groups 2, 3, and 4 and groups 3 and 4 were favored over group 2 at the 3- and 7-day incubation periods. Comparable effects were shown between groups 3 and 4 for all incubation periods and between groups 2 and 3 and groups 1 and 4 for the 1-day incubation.

CONCLUSIONS

Er:YAG laser used alone or in combination with rhPDGF-BB application may offer a promising periodontal therapy for conditioning root surfaces, although the combined application seemed to be slightly more effective. However, testing laser use in intervals and with parameters <60 mJ/pulse and 10 Hz is required to verify the minimum threshold values necessary to obtain complete root debridement and clarify optimal conditions for fibroblast cell attachment and growth. Further studies are needed to determine ideal parameters for creating the best environment for successful periodontal treatment.

Effects of citric acid and EDTA conditioning on exposed root dentin: An immunohistochemical analysis of collagen and proteoglycans

OBJECTIVE

Preservation of structural and biochemical properties of the root dentin matrix is crucial to favor healing and regenerative periodontal processes. Aim of this study was to evaluate the biochemical characteristics of collagen and chondroitin sulphate of root dentin surfaces exposed by periodontal disease after acid conditioning by means of an immunohistochemical technique.

DESIGN

Human teeth scheduled for extraction due to periodontal reason were submitted to: (A) scaling and root planning; (B) ultrasonic instrumentation; (C) no instrumentation. Teeth were then exposed to: (1) 10% citric acid; (2) 17% EDTA; (3) no etching. A double immunolabeling technique was performed to identify type-I collagen and proteoglycans and analyzed under FEI-SEM.

RESULTS

Use of 10% citric acid revealed intense labeling for collagen fibrils and proteoglycans; lower labeling was found after EDTA conditioning. Unetched specimens showed residual smear layer on the dentin surface resulting in no evident surface labeling.

CONCLUSIONS

This study supports the hypothesis that manual or ultrasonic instrumentation alone is not able to expose the sound dentin matrix, whereas a subsequent acidic conditioning exposes collagen fibrils and associated proteoglycans. The immunohistochemical technique revealed that despite their acidity, both citric acid and EDTA were able to preserve the structural and biochemical properties of the exposed dentin matrix.

Effect of EDTA Root Conditioning on the Healing of Intrabony Defects Treated With an Enamel Matrix Protein Derivative

BACKGROUND

Regenerative periodontal therapy with an enamel matrix protein derivative (EMD) has been shown to promote regeneration in intrabony periodontal defects. However, in most clinical studies, root surface conditioning with EDTA was performed in conjunction with the application of EMD, and, therefore, it cannot be excluded that the results may also be attributable to the effect of the root conditioning procedure. The purpose of this study was to determine the effect of root conditioning on the healing of intrabony defects treated with EMD.

METHODS

Twenty-four patients, each of whom exhibited one deep intrabony defect, were randomly treated with either open flap debridement (OFD) followed by root surface conditioning with EDTA and application of EMD (OFD+EDTA+EMD) or with OFD and application of EMD only (OFD+EMD). The following parameters were recorded at baseline and at 1 year: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL).

RESULTS

No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the OFD+EDTA+EMD group showed a reduction in mean PD from 9.3+/-1.3 mm to 4.0+/-0.9 mm (P<0.001), and mean CAL changed from 10.8+/-2.2 mm to 7.1+/-2.8 mm (P<0.001). In the OFD+EMD group, mean PD was reduced from 9.3+/-1.2 mm to 4.2+/-0.9 mm (P<0.001), and a change in mean CAL from 11.0+/-1.7 mm to 7.3+/-1.6 mm (P<0.001). There were no significant differences in any of the investigated parameters between the two groups.

CONCLUSION

In intrabony defects, regenerative surgery including OFD+EDTA+EMD failed to show statistically significant differences in terms of PD reduction and CAL gain compared to treatment with OFD+EMD.

A scanning electron microscopy study of root surface smear layer removal after topical application of EDTA plus a detergent

The aim of the present study was to compare root surface smear layer removal following topical application of EDTA and EDTA-T (Texapon). Extracted human teeth had their cementum removed and were mechanically scaled. A total of 220 root specimens were obtained and were randomly assigned to the following groups: I-saline solution (control), II-EDTA; III-EDTA-T. Groups II and III specimens were assigned to different EDTA gel concentrations: 5%, 10%, 15%, 20% and 24%. Smear layer removal score was assessed for each specimen by scanning electron microscopy. The results demonstrated that EDTA and EDTA-T gel led to a higher root surface smear layer removal when compared to the control group. The 5% EDTA gel also showed a higher smear layer removal than the 15%, 20% and 24% EDTA gels (p<0.05). No difference could be found between the different concentrations of EDTA-T gels tested (p>0.05). EDTA gels had statistically significantly lower smear layer scores than the EDTA-T gels for the 5% and 10% concentrations. The results suggested that topical application of EDTA or EDTA-T gel led to significant smear layer removal of the mechanically treated root surfaces. The addition of a detergent to the EDTA gel formula did not improve smear layer removal of the root surface.

Fibrin clot adhesion to dentin conditioned with protein constructs: an in vitro proof-of-principle study

OBJECTIVES

Periodontal regeneration is contingent on the adsorption, uninterrupted adhesion, and maturation of a fibrin clot to a periodontally compromised root surface. Clot adhesion appears vitally dependent on the formation of a resilient union between the clot and the root surface. Root surface demineralization will remove a root surface smear layer exposing dentin tubules and collagen matrix for enhanced clot adhesion. Recently, protein constructs have been introduced to condition the root during periodontal surgery. The effect of such root conditioning on clot adhesion has not been clarified. The objective of this study was to evaluate clot adhesion to protein conditioned dentin surfaces.

METHODS

Human dentin blocks (4 x 6 x 1 mm) were exposed to a saturated citric acid solution (CA) or a commercial ethylenediaminetetraacetic acid (EDTA) preparation using standardized protocols. Some dentin blocks were additionally conditioned with proteins, either bovine serum albumin (BSA) or an enamel matrix protein preparation (EMP). Fresh human whole blood was applied to the blocks. The blood was allowed to clot for 20 min. in a humidified chamber. The dentin blocks were rinsed 3 x 5 min. in phosphate-buffered saline under standardized conditions to test clot adhesion. They were then processed for scanning electron microscopy (SEM). Two masked examiners independently evaluated the SEM images.

RESULTS

CA removed the dentin smear layer, exposing dentin tubules and collagen. EDTA appeared less efficacious leaving smear layer residues. The BSA or EMP application resulted in a surface morphology similar to that of a smear layer. Fibrin clot adhesion was best supported by the CA-treated dentin surface. Forces produced by the rinse protocol partially removed the fibrin clot from EDTA-treated surfaces. BSA- or EMP-treated surfaces poorly retained the fibrin clot.

CONCLUSIONS

CA surface demineralization removes a dentin surface smear layer to promote adhesion of a fibrin clot. The EDTA gel appears less effective. Further conditioning of the dentin surface with protein constructs produces a surface morphology similar to that of the smear layer with poor fibrin clot retention.

Enamel matrix proteins and systemic antibiotics as adjuncts to non-surgical periodontal treatment: clinical effects

OBJECTIVES

The purpose of the present study was to evaluate the clinical effects of non-surgical periodontal treatment, supplemented with enamel matrix derivative (EMD) and/or systemic antibiotics, in deep periodontal pockets of patients with chronic periodontitis.

METHODS

This was a randomized, placebo-controlled longitudinal clinical trial of 12 months duration. Using a split-mouth design, 16 subjects were randomly assigned to scaling and root planing (SRP) with EMD or placebo in contra-lateral dentition areas. One half of the subjects received 250 mg metronidazole and 375 mg amoxicillin three times a day for 7 days and the other half received a placebo. One inter-proximal periodontal lesion was chosen as study site in each of the contra-lateral quadrants.

RESULTS

Subjects treated with systemic antibiotics yielded significantly better clinical results than those treated with placebo. In these cases, probing pocket depth was reduced significantly more after 6 months (3.0+/-2.1 mm versus 1.6+/-1.4 mm, p=0.05), and the mean clinical attachment gain was significantly greater after 6 months (2.3+/-1.9 mm versus 0.7+/-1.6 mm, p=0.02) and 12 months (2.3+/-3.5 mm versus 0.4+/-3.8 mm, p=0.02). Sites treated with the antibiotics plus EMD gained the largest amount of clinical attachment. There was no significant benefit of EMD adjunctive to SRP in subjects not treated with antibiotics.

CONCLUSIONS

The present study supports the notion that optimal repair and regeneration of the periodontium requires suppression of the microbiota causing periodontal disease.

Healing, post-operative morbidity and patient perception of outcomes following regenerative therapy of deep intrabony defects

AIM

This prospective multicenter randomized controlled clinical trial was designed to compare the clinical outcomes of papilla preservation flap surgery with or without the application of enamel matrix derivatives (EMD). This article reports on early healing events, post-operative morbidity and patient perceptions of the surgical outcomes.

MATERIAL AND METHODS

One hundred and seventy-two patients with advanced chronic periodontitis and at least one intrabony defect of > or =3 mm were recruited in 12 centres in seven countries (European Research Group on Periodontology (ERGOPERIO)). Papilla preservation flaps were used to obtain access and primary closure. After debridement, and root conditioning, EMD was applied in the test subjects, and omitted in the controls. Healing was monitored 1, 2, 3, 4, 6 and 12 weeks after surgery. During the first 12 weeks of healing, supracrestal soft-tissue density was evaluated with a computer-assisted densitometric image analysis system (CADIA) using underexposed radiographs taken on a subset of 34 patients. Patient perceptions were evaluated with a questionnaire immediately after the procedure, at suture removal 1 week later and at 1 year.

RESULTS

Subjects reported little intraoperative or post-operative pain or discomfort for both test and controls. Twenty-four percent of controls and 30% of tests (p=0.64) reported a degree of interference with daily activities for an average of 3 and 3.5 days, respectively. Post-surgical edema was noted in 25% of tests and 28% of controls. Wound dehiscence in the interdental portion of the flap was uncommon (14% of tests and 12% of controls at week 1) and of limited size. Root sensitivity was the most frequent post-operative adverse event: it affected 45% of test and 35% of controls (p=0.55). Up to 6 weeks post-operatively, soft-tissue densities were significantly higher in subjects treated with EMD with respect to controls. One year after completion of the surgery, patients reported high levels of satisfaction with the outcomes. The most frequently reported benefits included the ability to preserve a tooth/dentition and to maintain/improve chewing ability. The cost and need for frequent follow-ups were cited as significant drawbacks.

CONCLUSIONS

This study portrayed the early healing events, pain, discomfort and adverse events of papilla preservation flap surgery and the 1-year patient perceptions of the benefits and disadvantages of periodontal surgery in intrabony defects. Earlier gains in soft-tissue density were observed following application of EMD. In terms of patient-centered outcomes, however, both procedures performed in a similar manner.

Healing of intrabony defects following surgical treatment with or without an Er:YAG laser

AIM

The aim of this controlled, parallel design clinical study was to compare the healing of intrabony periodontal defects following treatment with access flap surgery with and without debridement with an Er:YAG laser.

METHODS

Twenty-three patients each of whom exhibited one deep intrabony defect were randomly treated with either access flap surgery followed by root surface and defect debridement using an Er:YAG laser (KEY3) (160 mJ, 10 Hz) (test), or with access flap surgery followed by root surface and defect debridement using hand and ultrasonic instruments (control). The following clinical parameters were recorded at baseline and at 6 months: plaque index; gingival index; bleeding on probing; probing depth (PD); gingival recession; and clinical attachment level (CAL). The primary outcome variable was CAL. No statistically significant differences between the groups were found at baseline.

RESULTS

No serious adverse events were observed after any of the treatments. The results have shown that in the test group the PD decreased from 7.8+/-1.3 to 4.1+/-1.3 mm (p<0.001) and the CAL changed from 9.8+/-2.9 to 7.2+/-2.5 mm (p<0.001). In the control group the PD decreased from 7.8+/-0.8 to 4.6+/-1.6 mm (p<0.001) and the CAL changed from 9.2+/-1.2 to 7.7+/-1.6 mm (p<0.01). The test group displayed a higher tendency for CAL gain, although this tendency did not prove to be statistically significant.

CONCLUSION

Within the limits of the present study, it can be concluded that: (i) at 6 months following treatment both therapies led to significant improvements of the investigated clinical parameters, and (ii) an Er:YAG laser may represent a suitable alternative for defect and root surface debridement in conjunction with periodontal surgery.

Treatment of intrabony defects with enamel matrix proteins or barrier membranes: results from a multicenter practice-based clinical trial

BACKGROUND

This prospective multicenter, randomized, controlled clinical trial compared the clinical outcomes of enamel matrix proteins (EMD) versus placement of a bioabsorbable membrane in conjunction with guided tissue regeneration (GTR).

METHODS

Seventy-five patients with advanced chronic periodontitis were recruited in seven centers in three countries. All patients had at least one intrabony defect of > or = 3 mm. Heavy smokers (> or = 20 cigarettes/day) were excluded. The surgical procedures included access for root instrumentation using the simplified papilla preservation flap and either the application of EMD or the placement of a GTR membrane. At baseline and 1 year following the interventions, clinical attachment levels (CAL), probing depths (PD), recession (REC), full-mouth plaque scores, and full-mouth bleeding scores were assessed. A total of 67 patients completed the study.

RESULTS

At 1 year, the EMD defects gained 3.1 +/- 1.8 mm of CAL, versus 2.5 +/- 1.9 mm for GTR defects. Probing depth reduction was 3.8 +/- 1.5 mm and 3.3 +/- 1.5 mm, respectively. A multivariate analysis indicated that the differences between EMD and GTR treatments were not significant while a center effect and baseline PD significantly influenced CAL gains. No significant differences in terms of frequency distribution of the outcomes were observed. All cases treated with GTR presented at least one surgical complication, mostly membrane exposure, while only 6% of EMD treated sites displayed complications (P < 0.0001).

CONCLUSIONS

The results of this trial failed to demonstrate superiority of one treatment modality over the other. GTR outcomes in this trial were lower than anticipated based on previous evidence. This was attributed to the high prevalence of post-surgical complications in the GTR group.

Effectiveness of EDTA and EDTA-T brushing on the removal of root surface smear layer

The purpose of this study was to compare the removal of root surface smear layer following active application of EDTA gel and EDTA-T (texapon) gel in different concentrations (5%, 10%, 15%, 20% and 24%), using scanning electron microscopy. A total of 220 dentin blocks obtained from the root surfaces of extracted teeth were divided into 3 groups: Group I - (control) application of saline solution (n = 20); Group II - EDTA gel (pH 7.0) was applied in the following concentrations: 5%, 10%, 15%, 20% and 24% (n = 100); Group III - EDTA-T gel (pH 7.0) applied in the same concentrations described above (n = 100). The photomicrographs were evaluated by one calibrated examiner using a smear layer removal index and following statistical analysis (Kruskal-Wallis test). The results demonstrated that the specimens treated with EDTA and EDTA-T gel presented a better smear layer removal than the control group (p < 0.01); no statistically significant differences were observed between the EDTA and EDTA-T groups and between the concentrations tested (Mann-Whitney, p > 0.05). Within the limits of this study, it can be concluded that all treatment modalities effectively removed the smear layer from the root surface. The addition of texapon into the EDTA gel formulation did not increase its effectiveness.

Clinical evaluation of the Er:YAG laser in combination with an enamel matrix protein derivative for the treatment of intrabony periodontal defects: a pilot study

OBJECTIVES

The aim of the present study was to compare the combination therapy of deep intrabony periodontal defects using an Er:YAG laser (ERL) and enamel matrix protein derivative (EMD) to scaling and root planing+ ethylenediaminetetraacetic acid (EDTA)+EMD.

MATERIAL AND METHODS

Twenty-two patients with chronic periodontitis, each of whom displayed 1 intrabony defect, were randomly treated with access flap surgery and defect debridement with an Er:YAG (160 mJ/pulse, 10 Hz) plus EMD (test) or with access flap surgery followed by scaling and root planing (SRP) with hand instruments plus EDTA and EMD (control). The following clinical parameters were recorded at baseline and at 6 months: plaque index, gingival index, bleeding on probing (BOP), probing depth (PD), gingival recession, and clinical attachment level (CAL). No differences in any of the investigated parameters were observed at baseline between the two groups.

RESULTS

Healing was uneventful in all patients. At 6 months after therapy, the sites treated with ERL and EMD showed a reduction in mean PD from 8.6 +/- 1.2 mm to 4.6 +/- 0.8 mm and a change in mean CAL from 10.7 +/- 1.3 mm to 7.5 +/- 1.4 mm (p < 0.001). In the group treated with SRP+EDTA+EMD, the mean PD was reduced from 8.1 +/- 0.8 mm to 4.0 +/- 0.5 mm and the mean CAL changed from 10.4 +/- 1.1 mm to 7.1 +/- 1.2 mm (p < 0.001). No statistically significant differences in any of the investigated parameters were observed between the test and control group.

CONCLUSION

Within the limits of the present study, it may be concluded that both therapies led to short-term improvements of the investigated clinical parameters, and the combination of ERL and EMD does not seem to improve the clinical outcome of the therapy additionally compared to SRP+EDTA+EMD.

Hard tissue formation on dentin surfaces applied with recombinant human bone morphogenetic protein-2 in the connective tissue of the palate

The purpose of this study was to evaluate whether hard tissue might be formed on dentin surfaces applied with recombinant human bone morphogenetic protein-2 (rhBMP-2) in palatal connective tissue. Fifty-eight dentin blocks were prepared from rat roots, demineralized with 24% EDTA (pH 7.0), applied with 0, 50 and 100 microgram/ml rhBMP-2, and labeled as groups 0, 50 and 100. The dentin blocks were then transplanted into palatal connective tissue of rats, and specimens were prepared at two and four weeks after surgery for histologic and histomorphometric examinations. The results showed that the percentage of newly formed hard tissue in relation to the total dentin block surface length in groups 0, 50 and 100 was 0.0%, 2.8% and 4.4% at two weeks, and 0.0%, 1.6% and 12.8% at four weeks, respectively. New hard tissue formation in groups 50 and 100 was significantly promoted as compared to group 0 (p < 0.01). These findings thus indicate that rhBMP-2 application to dentin enhanced new hard tissue formation on dentin surfaces in the connective tissue of the palate.

Enamel matrix proteins in the treatment of deep intrabony defects

BACKGROUND

The present study evaluated the healing of enamel matrix derivative (EMD) proteins in the treatment of periodontal lesions with deep intrabony defects.

METHODS

Ten deep intrabony defects in 7 periodontal patients were treated and followed for 1 year. The sites had a probing depth (PD) > or = 8 mm; clinical attachment level (CAL) > or = 9 mm, and intrabony component depth > or = 5 mm. All subjects received therapy prior to surgery and had a plaque score (PI) < or = 10%. Full thickness flaps were elevated buccally and lingually, granulation tissue was removed from the defects, and the root surfaces were planed. A 24% EDTA gel was applied followed by the enamel matrix protein preparation. The flaps were closed with interrupted sutures. The patients rinsed with a chlorhexidine solution twice a day for 6 weeks. They were recalled every 2 weeks for 6 months for professional tooth cleaning and then every 4 weeks for an additional 6 months. The experimental sites were re-examined 6 and 12 months after regenerative surgery.

RESULTS

At the 1-year examination, the mean CAL gain was 6.5 mm, the mean PD was 3.2 mm, and mean radiographic bone fill was 4.7 mm.

CONCLUSIONS

The application of enamel matrix proteins in combination with open flap curettage and root planing resulted in a gain of CAL and bone fill in deep intrabony defects.