Influence of tooth instrumentation roughness on subgingival microbial colonization

Assessing the effect of piezoelectric ultrasonic scaler tip wear on root surface roughness under influence of various working parameters: A profilometric and atomic force microscopic study

Background

Assessing the effect of scaler tip wear on the root surface roughness using piezoelectric ultrasonic scaling device under influence of various working parameters, i.e. power setting, lateral force, and instrumentation time.

Materials and Methods

An experimental study was conducted using 160 single-rooted tooth samples divided into two groups of new (n = 80) and worn tips (n = 80). Samples were prepared to examine the root surface roughness after being instrumented by new and worn piezoelectric ultrasonic tips (8 new/8 worn) at different parameters. The erosion ratio (ER) of the new/worn tip was examined under an atomic force microscope and roughness over root surface was measured by a contact surface profilometer. One-way analysis of variance test, post hoc Tukey's test, and independent t-test were used for intragroup, pair-wise multiple comparisons and intergroup comparison of average roughness (Ra) value.

Results

A statistically significant difference was found between the ER of new and worn scaler tips (P < 0.001). Intragroup comparison between subgroups 1 and 8 showed a higher Ra value in both the groups (P < 0.005). There was a significantly higher Ra value of worn tips compared to new tips (P < 0.05). Significantly higher mean Ra value was shown when lateral force changed from 50 g to 100 g (P < 0.005).

Conclusions

Increasing value of power setting, lateral force, and instrumentation time caused more surface roughness in worn-out scaler tips compared to new scaler tips. Lateral force and instrumentation time proved to be a major factor influencing surface roughness.

Influence of Manual and Ultrasonic Scaling on Surface Roughness of Four Different Base Materials Used to Elevate Proximal Dentin-Cementum Gingival Margins: An In Vitro Study

AIM

To evaluate and compare the effects of both manual and ultrasonic scaling on surface roughness of four different base materials, used for elevating dentin/cementum gingival margins of proximal cavities.

METHODS AND MATERIALS

Eighty human upper molars with compound Class II mesial cavities, with gingival margins 1 mm below the cemento-enamel junction (CEJ), were divided into four different groups according to the type of the base material used; resin-modified glass ionomer (RMGI), glass hybrid (HV-GIC), flowable bulk-fill resin composite (Bulk Flow) and bioactive ionic resin (Activa). This was followed by completing the restorations with the same resin composite. All materials were used according to the manufacturers' instructions. All groups were further subdivided into two subgroups according to the scaling technique: manual (hand) or ultrasonic. All restorative and scaling procedures were performed after fixation of specimens with acrylic beside neighboring teeth to simulate natural contact. The mean surface roughness (Ra, μm) of all specimens was measured quantitatively and qualitatively by a three-dimensional (3D) surface analyzer system at two stages; (1) after thermal cycling for 5000 cycles without scaling and (2) after scaling. Data were statistically analyzed using analysis of variance (ANOVA), Tukey post hoc tests, and paired sample t-tests (at α=0.05).

RESULTS

For baseline readings, the Bulk Flow group had the lowest Ra values, while HV-GIC group had the highest. RMGI and Activa groups had no statistical significant difference between their Ra values (p>0.05). For post scaling readings, hand scaling had significantly lower Ra values than ultrasonic scaling in all the material groups (p<0.05), except in the Bulk Flow group, where both scaling methods were not significantly different from each other (p>0.05).

CONCLUSION

Bulk Flow had the smoothest surfaces when cured against a matrix band compared with the other tested base materials. When hand and ultrasonic scaling methods were compared, the latter technique had more detrimental effect on the surface texture of the four tested base materials.

Clinical comparison of instrumentation systems for periodontal debridement: A randomized clinical trial

OBJECTIVE

To compare clinical efficacy, chairside time and post-treatment hypersensitivity of four instruments used for subgingival periodontal debridement.

MATERIALS & METHODS

Seventeen patients with stage II and III periodontitis were enrolled in this randomized clinical trial using a split-mouth design. Quadrants were randomly divided into four treatment groups: Group A: Gracey curettes-Hu-Friedy^® ; Group B: piezoelectric ultrasonic (Satelec^® ) with No.1S insert; Group C: diamond burs 40 µm (Intensiv Perioset^® ); and Group D: piezosurgery ultrasonic (Mectron^® ) with PP1 insert. Clinical outcomes, chairside time and hypersensitivity were assessed at 1, 2, 4 and 8 weeks after treatment. The primary outcome variable was improvement in clinical attachment level.

RESULTS

At 8 weeks post-treatment, Gracey curettes, piezoelectric ultrasonic (Satelec^® ) and piezosurgery ultrasonic (Mectron^® ) were statistically more effective than diamond burs in increasing attachment level and reducing probing pocket depth. Comparison of piezoelectric ultrasonic (Satelec^® ) and piezosurgery ultrasonic (Mectron^® ) with the other instruments showed a statistical difference (p < 0.001) in chairside time. Regarding post-treatment hypersensitivity, no statistical differences were observed in any of the groups.

CONCLUSIONS

Gracey curettes, piezoelectric ultrasonic (Satelec^® ) and piezosurgery ultrasonic (Mectron^® ) were clinically more effective than diamond burs 40 µm. The ultrasonic instruments showed a significant reduction in chairside time.

Subgingival instrumentation for treatment of periodontitis. A systematic review

OBJECTIVES

To evaluate the efficacy of subgingival instrumentation (PICOS-1), sonic/ultrasonic/hand instruments (PICOS-2) and different subgingival instrumentation delivery protocols (PICOS-3) to treat periodontitis.

METHODS

Systematic electronic search (CENTRAL/MEDLINE/EMBASE/SCOPUS/LILACS) to March 2019 was conducted to identify randomized controlled trials (RCT) reporting on subgingival instrumentation. Duplicate screening and data extraction were performed to formulate evidence tables and meta-analysis as appropriate.

RESULTS

As only one RCT addressed the efficacy of subgingival instrumentation compared with supragingival cleaning alone (PICOS-1), baseline and final measures from 9 studies were considered. The weighted pocket depth (PD) reduction was 1.4 mm (95%CI: 1.0 1.7) at 6/8 months, and the proportion of pocket closure was estimated at 74% (95%CI: 64-85). Six RCTs compared hand and sonic/ultrasonic instruments for subgingival instrumentation (PICOS-2). No significant differences were observed between groups by follow-up time point or category of initial PD. Thirteen RCTs evaluated quadrant-wise versus full-mouth approaches (PICOS-3). No significant differences were observed between groups irrespective of time-points or initial PD. Five studies reported patient-reported outcomes, reporting no differences between groups.

CONCLUSIONS

Nonsurgical periodontal therapy by mechanical subgingival instrumentation is an efficacious means to achieve infection control in periodontitis patients irrespective of the type of instrument or mode of delivery. Prospero ID: CRD42019124887.

Development and initial testing of an in vitro model simulating class II furcation defects

Objective

To compare surface topography of porcine and human root dentin and to develop a new in vitro model for class II furcation defects. The hypothesis for this study was that porcine mandible blocks can function as a model for class II furcation defects.

Background

Treatment of mandibular class II furcation defects is unpredictable. There is a need for in vitro models to investigate new treatment methods.

Methods

A model to investigate the surface topography of porcine and human root dentin was developed and the two tissues compared by SEM imaging and profilometer. A novel method for studying class II furcation defects was then tested. Blocks of porcine mandibles with molar 3 were prepared. Buccal class II furcation defects were created. The furcation area was isolated and bioluminescent Staphylococcus epidermidis Xen43 was used to form a biofilm in the furcation area to test the functionality of the novel furcation model.

Results

Micromechanical damage caused by debridement on porcine and human root dentin showed similar pattern. No significant difference in the surface morphological parameters was observed between the corresponding porcine and human samples. The model allowed for assessment of the root surface inside the furcation area. While the number of viable bacteria in the furcation following debridement could be quantified, no significant difference between the treatment groups was detected, likely due to bacterial colonization within the periodontal ligament space.

Conclusion

Porcine and human root dentin show similar surface topography following surface debridement. Porcine mandible blocks can function as a model for class II furcation defects. However, further development and refinement of the novel in vitro model is warranted.

Comparison of Root Surface Wear and Roughness Resulted from Different Ultrasonic Scalers and Polishing Devices Applied on Human Teeth: An In-Vitro Study

The aim of the present study was to compare the root surface wear and roughness, resulted from the professional dental hygiene instruments, including ultrasonic dental scalers, rubber prophy cups, and nylon bristle brushes, on the extracted human mandibular incisor teeth. Teeth (n = 80) were randomly assigned into eight groups according to the applied scaler type (Ma = Magnetostrictive, Pi = Piezoelectric), degree of power (M = Medium, F = Full), and angulation (0° and 45°). In the second stage, the specimens (n = 40) were further divided into two groups according to the applied polishing device (nylon bristle brush or rubber prophy cup). Laser scanner and contact profilometer devices were used for the surface analysis. Both ultrasonic instruments tested in our study produced rougher surfaces when full power was used at a 0° angle (p < 0.01). The highest wear (0.82 ± 0.07 mm3) and roughness values (0.30 ± 0.01 µm) were detected in the PiF0 group. Polishing performed with a rubber prophy cup resulted in almost twice the wear as well as a smoother surface when compared to polishing performed with a nylon bristle brush (p < 0.001). Variations in the application parameters of ultrasonic scalers and the type of polishing instrument might lead to significantly different root-surface characteristics.

Calculus Removal and Root Surface Roughness When Using the Er:YAG or Er,Cr:YSGG Laser Compared with Conventional Instrumentation Method: A Literature Review

Objective: The purpose of this literature review was to evaluate the effectiveness of using Er:YAG (erbium-doped yttrium/aluminum/garnet) laser or Er,Cr:YSGG (erbium, chromium-doped yttrium/scandium/gallium/garnet) laser on calculus removal and their effect on the topography and roughness of root surface in comparison with the conventional instruments in the nonsurgical periodontal therapy. Background data: One of the most challenging problems in treatment of periodontal disease is the elimination of plaque and calculus, leaving a clean and smooth root surface to decrease plaque and calculus retention, and for good gingival reattachment. Materials and methods: PubMed and Google Scholar were searched for available literature. The electronic search was limited to articles published in the period between January 2007 and April 2017, in the English language. Results: A total of 47 publications fulfilled the inclusion criteria of this systematic review and screened according to the research questions. Calculus removal using the ultrasonic instrument showed remaining calculus compared with the hand instrument, whereas, on the contrary, erbium lasers revealed no remaining calculus or smaller amounts compared with the conventional instruments when used in appropriate settings. The results of this review showed that ultrasonic instrumentation produced effects on the root surface almost similar to that of hand instrumentation. Er:YAG laser and Er,Cr:YSGG laser clarify a little more surface roughness when compared with conventional instruments. Conclusions: The present systematic review indicates that a combination of scaling and root planing (SRP) using the erbium lasers as an adjunctive therapy at certain parameters can be appropriate to remove residual debris from the root surface and at the same time have little or no negative thermal effect on the root surface. The Er:YAG laser also seems to be the most suitable for nonsurgical periodontal therapy. Additional new good-designed studies are needed to evaluate the effectiveness of erbium lasers with SRP in nonsurgical periodontal therapy.

Clinical evaluation of ultrasonic subgingival debridement versus ultrasonic subgingival scaling combined with manual root planing in the treatment of periodontitis: study protocol for a randomized controlled trial

BACKGROUND

Periodontal diseases are regarded as the most common diseases of mankind. The prevalence rate of periodontal disease assumes a clear growth tendency, increasing by 57.3% from 1990 to 2010. Thereby, effective periodontal therapy is still a long-term task and a difficult problem. The goals of periodontal therapy are to eliminate the infectious and inflammatory processes of periodontal diseases. Root planing, in order to eliminate the "infected cementum," has been an important step in the treatment of periodontitis since the 1970s. However, along with the understanding of the effects of endotoxin on the root surface, the necessity of manual root planing has been gradually queried. Ultrasonic instruments, which are more recent innovations, would not remove the cementum excessively, and are also more time-saving and labor-saving compared to using hand instruments. Hence, an increasing number of dentists prefer to do scaling with ultrasonic instruments only. However, the necessity of root planing remains emphasized in the international mainstream views of periodontal mechanical treatment. Therefore, this study is devoted to compare the clinical effect of ultrasonic subgingival debridement and ultrasonic subgingival scaling combined with manual root planing, which takes the implementation of root planing as the only variable and is more in line with the current clinical situation, thus hoping to provide some valuable reference to dentists.

METHODS/DESIGN

Forty adult patients who fit the inclusion criteria are being recruited from the Peking University Hospital of Stomatology (Beijing, China). By means of randomization tables, one quadrant of the upper and lower teeth is the test group and the other is the control group. Test group: ultrasonic subgingival scaling combined with manual root planing.

CONTROL GROUP

ultrasonic subgingival debridement. In a 24-week follow-up period, plaque index, probing depth, clinical attachment loss, bleeding index, furcation involvement, mobility, and patient-reported outcome (Visual Analog Scale for pain and sensitivity) will be observed and documented.

DISCUSSION

This study evaluates the effectiveness of ultrasonic subgingival scaling combined with manual root planing and ultrasonic subgingival debridement alone in the nonsurgical treatment of periodontitis with a split-mouth design after 1, 3 and 6 months. The result of the trial should potentially contribute to an advanced treatment strategy for periodontitis with an ideal clinical outcome.

TRIAL REGISTRATION

International Clinical Trials Registry Platform (ICTRP), ID: ChiCTR1800017122. Registered on 12 July 2018.

The effect of miniaturized manual versus mechanical instruments on calculus removal and root surface characteristics: An in vitro light microscopic study

Objectives

The aim of this study was to evaluate by light microscopy analysis the effect of the use of miniaturised piezoelectric tips versus mini‐five area specific curets on calculus removal and postoperative root surface alterations.

Methods

A total of 20 extracted teeth were used. Two square surfaces (5×5 mm) were marked on each root surface with a diamond bur mounted on a high‐speed handpiece. Before and after instrumentation, a series of magnified images (4.2×) of each experimental surface were taken with a standardized approach. According to a randomization list, the two surfaces on each sample were instrumented in a standardised fashion either with a mine‐five curet or a slim piezoelectric tip. The images were processed using an imaging software. Data were summarised as means and standard deviations for the two outcomes (calculus and alterations.) at each time (pre and post) for both of the groups (manual and mechanical).

Results

Both manual and mechanical instrumentation significantly reduced the calculus deposits (p < .001) without significant differences between the two groups. Both manual and mechanical treatments significantly increased alterations (p < .01). There was a statistically significant evidence of a greater increase in alterations from mechanical treatment.

Conclusions

Slim mechanical piezoelectric tips and manual mini‐five area‐specific curets have similar effects on calculus removal. Manual instrumentation results in a more homogeneous postoperative root surface with less root alterations.

Nonsurgical and surgical treatment of periodontitis: how many options for one disease?

Treatment of periodontitis aims at preventing further disease progression with the intentions to reduce the risk of tooth loss, minimize symptoms and perception of the disease, possibly restore lost periodontal tissue and provide information on maintaining a healthy periodontium. Therapeutic intervention includes introduction of techniques to change behavior, such as: individually tailored oral-hygiene instructions; a smoking-cessation program; dietary adjustment; subgingival instrumentation to remove plaque and calculus; local and systemic pharmacotherapy; and various types of surgery. No single treatment option has shown superiority, and virtually all types of mechanical periodontal treatment benefit from adjunctive antimicrobial chemotherapy. Periodontal treatment, because of the chronic nature of periodontitis, is a lifelong commitment to intricate oral-hygiene techniques, which, when properly implemented, will minimize the risk of disease initiation and progression.

Comparison of clinical parameters, microbiological effects and calprotectin counts in gingival crevicular fluid between Er: YAG laser and conventional periodontal therapies: A split-mouth, single-blinded, randomized controlled trial

BACKGROUND

The erbium-doped yttrium, aluminum, and garnet (Er:YAG) laser is thought to be the most promising laser for periodontal treatment; however, its application is still under consideration. The aim of this study was to compare Er:YAG laser monotherapy with conventional scaling and root planing (SRP) for chronic periodontitis using clinical parameters, the detection rate of periodontal pathogens, and the calprotectin level in gingival crevicular fluid.

METHODS

Twenty-seven participants with moderate-to-advanced chronic periodontitis were included. In a split-mouth design, the 2 half-mouths of each participant were randomly assigned to Er:YAG laser or SRP (combination of ultrasonic and manual instruments) treatment. Clinical parameters were recorded at baseline, 6 weeks, and 3 and 6 months after treatment. At the same time points, gingival crevicular fluid was collected to analyze the detection rate of 6 periodontal pathogens by polymerase chain reaction and the levels of calprotectin by enzyme-linked immunosorbent assay.

RESULTS

Both treatment groups showed significant reductions in probing depth (PD), bleeding index (BI), and clinical attachment level (CAL) from baseline to 6 months. For sites with 4 mm ≤ PD ≤ 6 mm at baseline, SRP resulted in a greater reduction in PD and CAL than Er:YAG laser treatment, and the difference remained at 6 months post-treatment (P = .01 and P < .01, respectively). For sites with PD ≥7 mm at baseline, the clinical parameters showed similar results between the 2 groups. SRP resulted in a lower detection rate of Porphyromonas gingivalis at 6 months post-treatment. The levels of calprotectin were significantly decreased from baseline to 6 months in both groups, without a significant difference between the groups.

CONCLUSION

For mild pockets, conventional SRP may still be the preferred choice. For deep pockets, Er:YAG laser treatment could be an effective alternative. Studies are needed to explore more advanced instruments and new application methods for the Er:YAG laser for periodontal treatment in deep pockets.

Evaluating the Whitening and Microstructural Effects of a Novel Whitening Strip on Porcelain and Composite Dental Materials

AIMS

The aim of this project was to evaluate the effects of 2 different whitening strips on color, microstructure and roughness of tea stained porcelain and composite surfaces.

METHODS

54 porcelain and 72 composite chips served as samples for timed application of over-the-counter (OTC) test or control dental whitening strips. Chips were divided randomly into three groups of 18 porcelain and 24 composite chips each. Of these groups, 1 porcelain and 1 composite set served as controls. The remaining 2 groups were randomized to treatment with either Oral Essentials® Whitening Strips or Crest® 3D White Whitestrips™. Sample surface structure was examined by light microscopy, profilometry and Scanning Electron Microscopy (SEM). Additionally, a reflectance spectrophotometer was used to assess color changes in the porcelain and composite samples over 24 hours of whitening. Data points were analyzed at each time point using ANOVA.

RESULTS

In the light microscopy and SEM images, no discrete physical defects were observed in any of the samples at any time points. However, high-resolution SEM images showed an appearance of increased surface roughness in all composite samples. Using profilometry, significantly increased post-whitening roughness was documented in the composite samples exposed to the control bleaching strips. Composite samples underwent a significant and equivalent shift in color following exposure to Crest® 3D White Whitestrips™ and Oral Essentials® Whitening Strips.

CONCLUSIONS

A novel commercial tooth whitening strip demonstrated a comparable beaching effect to a widely used OTC whitening strip. Neither whitening strip caused physical defects in the sample surfaces. However, the control strip caused roughening of the composite samples whereas the test strip did not.

Effects of Root Debridement With Hand Curettes and Er:YAG Laser on Chemical Properties and Ultrastructure of Periodontally-Diseased Root Surfaces Using Spectroscopy and Scanning Electron Microscopy

Introduction: The efficacy of erbium-doped yttrium aluminum garnet (Er:YAG) laser for root debridement in comparison with curettes has been the subject of many recent investigations. Considering the possibility of chemical and ultra-structural changes in root surfaces following laser irradiation, this study sought to assess the effects of scaling and root planing (SRP) with curettes and Er:YAG laser on chemical properties and ultrastructure of root surfaces using spectroscopy and scanning electron microscopy (SEM). Methods: In this in vitro experimental study, extracted sound human single-rooted teeth (n = 50) were randomly scaled using manual curettes alone or in conjunction with Er:YAG laser at 100 and 150 mJ/pulse output energies. The weight percentages of carbon, oxygen, phosphorous and calcium remaining on the root surfaces were calculated using spectroscopy and the surface morphology of specimens was assessed under SEM. Data were analyzed using one-way analysis of variance (ANOVA). Results: No significant differences (P > 0.05) were noted in the mean carbon, oxygen, phosphorous and calcium weight percentages on root surfaces following SRP using manual curettes with and without laser irradiation at both output energies. Laser irradiation after SRP with curettes yielded rougher surfaces compared to the use of curettes alone. Conclusion: Although laser irradiation yielded rougher surfaces, root surfaces were not significantly different in terms of chemical composition following SRP using manual curettes with and without Er:YAG laser irradiation. Er:YAG laser can be safely used as an adjunct to curettes for SRP.

The effect of various ultrasonic and hand instruments on the root surfaces of human single rooted teeth: A Planimetric and Profilometric study

Background:

The purpose of this study was to compare the effectiveness of different ultrasonic scalers and a periodontal curette on the root surfaces for calculus removal and root surface roughness.

Materials and Methods:

40 single rooted teeth with subgingival calculus destined for extraction were assigned to one of three experimental groups (n = 10, in each group) and one control group (untreated, n = 10). Experimental groups were: Group 1: Piezoelectric ultrasonic group; Group 2: Magnetostrictive ultrasonic group; Group 3: Hand instrumentation group (Curette). After instrumentation, the teeth were extracted and the presence of residual deposits and root surface roughness were analyzed using Planimetric analyzing tool (Tool that measures the area of a plane figure as a mechanically coupled pointer traversing the perimeter of figure) and Surface Profilometer (Instrument used for profiling of an object). Root surface characteristics were evaluated qualitatively using SEM. Standardization of force, angulations and adaptation of instrument couldn’t be achieved in our study due to in vivo study design rather than in vitro design in previous studies where procedure was done on the extracted teeth samples.

Results:

The results of the study showed that residual deposits were similar in all experimental groups. With respect to roughness parameters, Rq (Root mean square roughness) and Rt (Total roughness) a significant difference was observed (P < 0.001) among hand instrumentation and ultrasonic devices. SEM analysis revealed a similar root surface pattern for the ultrasonic devices, but curette showed many instrument scratches, gouges, and removal of large amount of cementum.

Conclusions:

Curette produced the rougher root surfaces than two ultrasonic devices used in the study and caused more root surface removal. Piezoelectric devices produced minimum root surface roughness but caused more root substance removal and more cracks than Magnetostrictive ultrasonic devices.

Atomic force microscopy and scanning electron microscopy evaluation of efficacy of scaling and root planing using magnification: A randomized controlled clinical study

Aim:

A randomized controlled clinical study was undertaken to evaluate the effectiveness of scaling and root planing (SRP) by using Magnifying Loupes (ML) and dental operating microscope (DOM).

Materials and Methods:

A total of 90 human teeth scheduled for extraction from 18 patients aged between 25 and 65 years suffering from generalized chronic severe periodontitis were randomly assigned to three treatment groups. Group 1 consisted SRP performed without using magnification (unaided), Group 2-SRP with ML and Group 3-SRP with DOM. Following extractions, samples were prepared for (i) evaluation of surface topography by atomic force microscopy, (ii) presence of smear layer, debris by scanning electron microscopy (iii) elemental analysis by energy dispersive X-ray analysis. Data was subjected to statistical analysis using analysis of variance, post-hoc (Tukey-HSD) and Chi-square test.

Results:

Statistically significant (P < 0.001) difference was found among the different treatment groups. Group 3 was the best while Group 1 was the least effective technique for SRP. Order of efficacy in terms of the surface was found to be - Palatal < Lingual < Distal ≃ Mesial < Buccal. Efficiency in mandibular to maxillary teeth was found to be significant (P < 0.05), also anterior to posterior teeth (P < 0.05).

Conclusion:

Magnification tools significantly enhance the efficacy of supragingival and subgingival SRP.

A comparison of magnetostrictive and piezoelectric ultrasonic scaling devices: an in vitro study

Purpose

The effects of magnetostrictive and piezoelectric devices on tooth surfaces seem to differ with regard to the root surface roughness they produce. This study aimed to compare the results of scaling using magnetostrictive and piezoelectric devices on extracted teeth.

Methods

Forty-four human extracted teeth were assigned to four study groups (n=11). In two groups (C100 and C200), the teeth were scaled using a magnetostrictive device and two different lateral forces: 100 g and 200 g, respectively. In the other two groups (P100 and P200), the teeth were scaled with a piezoelectric device with 100 g and 200 g of lateral force, respectively. he teeth were scaled and the data on the duration of scaling and the amount of surface were collected and analyzed using the t-test.

Results

The mean time needed for instrumentation for the piezoelectric and magnetostrictive devices was 50:54 and 41:10, respectively, but their difference was not statistically significant (P=0.171). For root surface roughness, we only found a statistically significantly poorer result for the C200 group in comparison to the P200 group (P=0.033).

Conclusions

This study revealed that applying a piezoelectric scaler with 200 g of lateral force leaves smoother surfaces than a magnetostrictive device with the same lateral force.

Influence of tip wear of piezoelectric ultrasonic scalers on root surface roughness at different working parameters. A profilometric and atomic force microscopy study

Roughness on tooth surfaces is reported to facilitate the reestablishment of microbial dental plaque. Hence, the main goal of dental scaling is to remove bacterial plaque and obtain smoother tooth surfaces. This study was aimed to assess the influence of tip wear of ultrasonic scaler inserts on root surface roughness at different working parameters. Twenty piezoelectric ultrasonic scaler inserts (10 worn/10 new) were selected to examine the erosion ratio (ER) on the scaler tips and to assess the influence of tip wear on root surface roughness. Erosion on the tip surfaces was evaluated under atomic force microscopy (AFM). Root samples were prepared and instrumented by new (Group I) and worn (Group II) inserts at different working parameters. Roughness change (Rc) on root surfaces after instrumentation was examined under profilometer and compared between and within the groups. Statistically significant differences were found between the mean ERs of new and worn tips (P < 0.01). The results of this study showed that tip angulation and instrument power strongly influenced the Rc values on instrumented samples (P < 0.05). It was also revealed that tip wear influenced the Rc values on root surfaces especially at 45° tip angulation (P < 0.05). Therefore, tip wear should also be considered as much as the other parameters to minimize the surface roughness during ultrasonic treatment.

Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning

Objective

The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning.

Material and Methods

A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group). After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained.

Results

Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples.

Conclusion

Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning.

A morphological survey of root grooves and their influence on periodontal attachment loss

Periodontal health reflects a balance between harmful and protective elements in the gingival marginal area. The total plaque mass, specific periodontopathogens, the tooth morphology, and local environmental factors may challenge this balance. The periodontal ligament attachment loss shifts this balance adversely toward the periodontal disease.

OBJECTIVES

The aim of this retrospective study was to determine the significance of proximal root grooves as a risk factor in the periodontal attachment loss; the effect of their dimensions and locations has been evaluated.

MATERIALS AND METHODS

One hundred (100) extracted formalin stored single rooted permanent anterior teeth were studied by staining with 0.1% toludine blue to visualize attached periodontal ligament remnants. On each tooth, the loss of attachment was measured from the cemento-enamel junction to the most coronal level of the stained periodontal ligament remnants.

RESULTS

The prevalence of proximal root grooves was found to be 81% and a statistically significant greater loss of attachment was present on grooved than on non-grooved surfaces (p < 0.01).

CONCLUSIONS

Generally, there was direct relationship between groove location, its dimensions, and maximum loss of attachment. The results suggest that proximal root grooves should be considered in periodontal diagnosis, prognosis, and treatment planning.

Comparative in vitro study of root roughness after instrumentation with ultrasonic and diamond tip sonic scaler

Objective:

The purpose of this study was to evaluate the root surface roughness after instrumentation with hand curette and diamond-coated sonic and universal ultrasonic tips.

Materials and Methods:

Forty root surfaces of human teeth were randomly assigned to four treatment groups: control group (without instrumentation), curette instrumentation, ultrasonic instrumentation with universal tip and sonic instrumentation with diamond-coated tip. Each sample was instrumented with fifteen strokes. Before and after instrumentation, surface roughness was measured. In addition, the root surface topography was examined after treatment under the scanning electron microscope.

Results:

Significant statistical differences (p<0.05) were observed when comparing the control group (0.48±0.07mm) to the treated groups (hand - 1.246±0.279mm, ultrasonic - 1.468±0.177mm and sonic instrumentation - 1.576±0.20mm). The highest roughness was produced by diamond-coated sonic tip and by ultrasonic universal tip (p>0.05).

Conclusion:

The diamond-coated tip with sonic scaler instrumentation and ultrasonic instrumentation produce similar root surface roughness, higher than curette instrumentation.

Effects of sonic and ultrasonic scaling on the surface roughness of tooth-colored restorative materials for cervical lesions

This study investigated the effects of sonic and ultrasonic scaling on the surface roughness of five commonly used tooth-colored restorative materials for Class V cavities, including a flowable resin composite (Tetric Flow), a compomer (Compoglass F), a glass ionomer (Fuji II), a resin-modified glass ionomer (Fuji II LC Imp) and a resin composite (Z100). Twenty rectangular block specimens (16 x 6 x 1.5 mm) of each material were cured against matrix strips, then stored in artificial saliva for two months before performing the periodontal instrumentation. Each specimen was divided into two experimental zones, and both scaling treatments were performed on each sample. The surface roughness (Ra) of these materials was determined before and after the different instrumentations, and differences were evaluated with the use of a profilometer. Data were statistically analyzed using repeated measures of ANOVA with Tukey's multiple comparisons and paired t-tests at a significance level of 0.05. Significant increases in surface roughness of all test materials were recorded from both scaling treatments. With the exception of Tetric Flow, ultrasonic scaling had more adverse effects on the surface roughness of all test materials compared to sonic scaling. For the test materials Z100 and Tetric Flow, resin composites showed the least surface changes in both scaling treatments, while Fuji II glass ionomer demonstrated the greatest roughness after instrumentation. More importantly, the mean surface roughness values of several materials after instrumentation were above the critical threshold roughness of 0.2 microm.

Root surface removal and resultant surface texture with diamond-coated ultrasonic inserts: an in vitro and SEM study

BACKGROUND

A new diamond-coated ultrasonic insert has been developed for scaling and root planing, and it was evaluated in vitro for the amount of root surface removed and the roughness of the residual root surface as a result of instrumentation.

METHODS

48 extracted single-rooted human teeth were ground flat on one root surface and mounted (flat side up) in PVC rings of standard height and diameter with improved dental stone. Each tooth surface was treated with either a plain ultrasonic insert (PI), an ultrasonic insert with a fine grit diamond coating (DI) or sharp Gracey curettes (HI). The mounted teeth were attached to a stepper motor which drove the teeth in a horizontal, reciprocal motion at a constant rate. The thickness from the flattened bottom of the ring to the flattened tooth surface was measured before and after 10, 20, and 30 instrumentation strokes for each root surface with each of the experimental instruments. A number of treated teeth were randomly selected for examination with SEM and a profilometer. Statistical analysis (analysis of co-variance) was performed to compare the amounts of tooth structure removed among the 3 instruments and t-test was used to compare the roughness of the treated root surfaces.

RESULTS

The mean depth of root structure removed was PI 10.7 microm, HI 15.0 microm, and DI 46.2 microm after 10 strokes; and PI 21.6 microm, HI 33.2 and DI 142.0 microm after 30 strokes, respectively. On average, 0.9 microm, 1.3 microm, and 4.7 microm of root surface was removed with each stroke of PI, HI and DI, respectively. PI and HI were not different from each other for all the stroke cycles, while DI was significantly different from PI and HI for all the stroke cycles (p<0.0001). Analysis with the profilometer showed that the smoothest surface was produced by the PI followed by the HI. The DI produced a surface that was significantly rougher than the surface produced by the PI or HI.

CONCLUSION

These results suggest that diamond-coated ultrasonic instruments will effectively plane roots, and that caution should be used during periodontal root planing procedures. Additionally, the diamond-coated instruments will produce a rougher surface than the plain inserts or the hand curettes.

Influence of Parameters on Root Surface Roughness Following Treatment With a Magnetostrictive Ultrasonic Scaler: An In Vitro Study

BACKGROUND

This in vitro study aimed to evaluate the influence of different parameters, i.e., lateral force, instrument power setting, and the shape of the working tip, on the roughness of root surfaces following treatment with a magnetostrictive ultrasonic scaling device.

METHODS

The study sample comprised a total of 102 extracted human molars, premolars, canines, and incisors. The samples were randomly divided into 10 equal units of 10 each for treatment with the ultrasonic device at a lateral force of 0.5 N and 2.0 N, a low and high instrument power setting, and with a straight and angulated shaped working tip. Twenty samples were treated manually using curets at a lateral force of 0.5 N and 2.0 N. Two samples were left untreated as controls. The mean (Ra) and maximum (Rmax) surface roughness of each sample was recorded. The statistical analysis was performed using analysis of variance (three-way ANOVA) at a level of significance of 5% (P < 0.05).

RESULTS

The mean surface roughness (+/-SD) using different parameters ranged from 0.6 +/- 0.1 microm to 1.8 +/- 0.3 microm. The maximum surface roughness (+/-SD) was between 4.8 +/- 1.3 microm and 17.2 +/- 4.3 microm. The mean surface roughness (+/-SD) for samples treated with curets at a lateral force of 0.5 N was 0.5 +/- 0.0 microm and 0.4 +/- 0.1 microm at 2.0 N. The maximum surface roughness (+/-SD) was 3.7 +/- 0.8 microm at 0.5 N and 3.9 +/- 1.4 microm at 2.0 N.

CONCLUSIONS

The findings of the present study indicate that the shape of the working tip and the lateral force significantly influence the mean and maximum surface roughness of root surfaces treated with a magnetostrictive ultrasonic scaling device. At any specific parameter, the surface roughness was significantly higher for the ultrasonic scaling device as compared to the hand curet.

Surface wear on cervical restorations and adjacent enamel and root cementum caused by simulated long-term maintenance therapy

BACKGROUND

In an in vitro study, the surface wear on cervical restorations and adjacent enamel and root cementum caused by different tooth-cleaning methods in simulated long-term therapy was investigated.

METHODS

Cervical restorations of amalgam (Oralloy), modified composite resin (Dyract), glass-ionomer cement (ChemFill Superior), and composite (Tetric) were instrumented by POL (polishing), CUR+POL (curette and polishing), US+POL (ultrasonic device with polishing) and the polishing agents Cleanic and Proxyt in a computer-controlled test bench. Treatment time corresponding to a real-time period of 5 or 10 years. Substance loss from instrumented surfaces was measured with a digital gauge. A three-way anova was used in the statistical evaluation.

RESULTS

The results showed that POL led to slight substance loss, which was greater using Cleanic (27 microm) than Proxyt (5 microm). CUR+POL produced a significantly greater substance loss than did US+POL, with 186 microm versus 35 microm on glass-ionomer cement, respectively, and 123 microm versus 18 microm, respectively, on root cementum, followed by composite (111 microm versus 27 microm, respectively), polyacid modified composite resin/compomer (89 microm versus 36 microm), amalgam (75 microm versus 19 microm), and enamel (32 microm versus 23 microm).

CONCLUSIONS

As opposed to the use of US+POL or POL, substance loss on cervical restorations and especially root cementum must be expected to result from tooth-cleaning during long-term maintenance treatment using CUR+POL.

Efficacy of subgingival calculus removal with Er:YAG laser compared to mechanical debridement: an in situ study

OBJECTIVES

The aim of the present study was to compare the effectiveness of subgingival calculus removal from periodontally involved root surfaces with an Er:YAG laser compared to hand instrumentation in situ.

METHODS

The mesial and distal surfaces of 30 single-rooted teeth with untreated periodontitis were treated either by hand instrumentation (scaling and root planing (SRP)) or by Er:YAG laser irradiation with the aim of achieving a calculus-free root surface. Subgingival plaque samples were obtained before and immediately after treatment for microbiological evaluation by culture and DNA probe analysis. The teeth were extracted and the residual calculus was measured by means of digitized planimetry. The morphology of the root surface was evaluated by scanning electron microscopy, and undecalcified sections were analyzed to determine residual calculus and the extent of cementum removal following both treatments.

RESULTS

Following laser irradiation, 68.4+/-14.4% of the root surface was calculus free in contrast to 93.9+/-3.7% after SRP when both treatments were performed for the same time (2:15+/-1:00 min). If laser irradiation was allowed twice the time used for hand instrumentation, 83.3+/-5.7% of the root surface was devoid of calculus. The effectiveness of both treatments was not related to initial probing depth. The histologic evaluation showed that after SRP 73.2% of root dentin was completely denuded from cementum, while only a minimal cementum reduction was apparent after laser irradiation. Both treatment modalities resulted in a similar reduction of periodontopathogens.

DISCUSSION

The present investigation could demonstrate the in vivo capability of the Er:YAG laser to remove calculus from periodontally involved root surfaces, although the effectiveness did not reach that achieved by hand instrumentation. The lack of cementum removal in contrast to SRP may qualify the laser as an alternative approach during supportive periodontal therapy.

Tooth substance loss resulting from mechanical, sonic and ultrasonic root instrumentation assessed by liquid scintillation

AIMS

This study investigated the loss of tooth substance (microg) by means of liquid scintillation in combination with profilometric and SEM analyses in order to evaluate the roughness and morphological changes of the root surface before and after instrumentation.

METHOD

40 polished and irradiated bovine root surfaces were scaled in vitro while covered with 50 ml distilled water using a sonic prototype (Periosonic 1/2), a magnetostrictive ultrasonic (Cavitron with Slimline inserts) scaler and a hand curette. Pressures were applied for the Periosonic, Cavitron and hand curette at 500, 500 and 30 g respectively, for 30-s intervals, up to 120 s. Loss of apatite (microg) was determined from the decays/min (32P) of the water samples using the radiochemical method of liquid scintillation. Replicas were made of the specimens for SEM and profilometric analyses.

RESULTS

The least substance loss was noted significantly (p<0.01) at all time intervals after Slimline, followed by the fine sonic prototype Periosonic 2, then the Periosonic 1 and finally the hand curette. In contrast, profilometric and SEM analyses revealed the smoothest root surfaces after the hand curette, whereas Cavitron produced a less smooth surface.

CONCLUSION

It can be concluded that this method can reveal very precisely small quantities of substance lost and, in combination with SEM analysis and microroughness measurements, be of considerable value in evaluating the aggressiveness and efficacy of periodontal instruments.

Position paper: sonic and ultrasonic scalers in periodontics. Research, Science and Therapy Committee of the American Academy of Periodontology

Ultrasonic and sonic scalers appear to attain similar results as hand instruments for removing plaque, calculus, and endotoxin. Ultrasonic scalers used at medium power seem to produce less root surface damage than hand or sonic scalers. Due to instrument width, furcations may be more accessible using ultrasonic or sonic scalers than manual scalers. It is not clear whether root surface roughness is more or less pronounced following power-driven scalers or manual scalers. It is also unclear if root surface roughness affects long-term wound healing. Periodontal scaling and root planing includes thorough calculus removal, but complete cementum removal should not be a goal of periodontal therapy. Studies have established that endotoxin is weakly adsorbed to the root surface, and can be easily removed with light, overlapping strokes with an ultrasonic scaler. A significant disadvantage of power-driven scalers is the production of contaminated aerosols. Because ultrasonics and sonics produce aerosols, additional care is required to achieve and maintain good infection control when incorporating these instrumentation techniques into dental practice. Preliminary evidence suggests that the addition of certain antimicrobials to the lavage during ultrasonic instrumentation may be of minimal clinical benefit. However, more randomized controlled clinical trials need to be conducted over longer periods of time to better understand the long-term benefits of ultrasonic and sonic debridement.

The influence of anatomic and iatrogenic root surface characteristics on bacterial colonization and periodontal destruction: a review

PERIODONTITIS IS A MULTIFACTORIAL infectious disease affecting primarily a subset of subjects and a subset of sites. Recent microbiological data have acknowledged that before disease progression can occur, a susceptible host and site are required, in addition to the presence of pathogenic bacteria. This review discusses factors affecting periodontal disease progression and focuses in particular on the influence of anatomic and iatrogenic root surface characteristics. Retrospective studies clearly suggest a strong association between anatomic aberrations and periodontal attachment loss. Cemental tear seems to have the potential to initiate an aseptic, rapid, site-specific periodontal breakdown in a non-infected environment, illustrating the complexity of the attachment loss process. Recent experimental findings, furthermore, demonstrate a significant influence of root surface instrumentation roughness upon subgingival plaque formation and gingival tissue reactions, as well as a significant and positive relationship between subgingival plaque accumulation and inflammatory cell mobilization. These results indicate that subgingivally located irregularities may form stagnant sites or ecological niches which favor both retention and growth of organisms. Such events in addition to the progressive inflammatory changes may critically influence the subgingival environment by turning a stable site into an unstable or active periodontitis site. Thus, local anatomic and iatrogenic root surface characteristics may have a more profound effect on gingival health than previously assumed, particularly on a site level.

A correlation study of inflammatory cell mobilization in response to subgingival microbial colonization

This study evaluated site-by-site the relations between subgingival microbial colonization and gingival tissue reactions. Experimental, deep periodontal defects were established at buccal surfaces of mandibular and maxillary canine teeth in 5 beagle dogs. The root surfaces were instrumented by a flame-shaped, fine-grained, rotating diamond point, or by a sharp curet. Following a 10-day postsurgical healing period, the dogs were fed a plaque-inducing diet for 70 days. The animals were then sacrificed and tissue blocks of the experimental sites including teeth and periodontal tissues were secured. The buccal gingiva was removed and processed for histomorphometric analysis while the teeth were prepared for scanning electron microscopic evaluation of the extent of subgingival microbial colonization. The results revealed that inflammatory cell density in the junctional epithelium and in the connective tissue were positively correlated to subgingival microbial colonization (P < 0.01). Furthermore, the degree of significance decreased with increasing distance from the plaque. The present study demonstrates that a close relation may exist between the extent of subgingival microbial colonization and inflammatory gingival tissue reactions.

Cemental tear: a risk factor in periodontal attachment loss

The objective of this retrospective study was to evaluate the influence of cemental tear as a risk factor in periodontal attachment loss. Seventeen extracted, single-rooted teeth showing loss of attachment and having one cemental tear surface and one opposite intact surface were examined. The teeth were stained in 0.1% toluidine blue to visualize attached periodontal ligament remnants and examined in a light microscope under incident light. On each tooth, loss of attachment was measured along the long axis of the root from the cemento-enamel junction to the most coronal level of the periodontal ligament on intact as well as on defect surfaces. Cemental tear surfaces demonstrated a significantly greater loss of attachment than opposite intact surfaces (P < 0.0001). In one specimen, the cemental tear fragment was partially attached to the root after the extraction procedure. This specimen was processed for light microscopy to determine the location of the cemental tear fracture. Histological examination clearly revealed that the split between the root and the fragment had occurred along the cemento-dentinal border. The results indicate that cemental tear should be considered as a possible etiologic entity in localized rapid periodontal breakdown.

Influence of tooth instrumentation roughness on gingival tissue reactions

Histological studies have demonstrated a relationship between the amount of subgingival plaque and the magnitude and extension of gingival tissue reactions. The objective of the present study was to evaluate inflammatory reactions in the gingival tissues facing plaque accumulation at a diamond and curet-instrumented root surfaces. Experimental, deep periodontal defects were established at buccal surfaces of mandibular and maxillary canine teeth in 5 beagle dogs. The root surfaces were instrumented by a flame-shaped, fine-grained. rotating diamond point, or by a sharp curet. Next, the dogs were fed a plaque-inducing diet for 70 days. The animals were then sacrificed, and tissue blocks of the experimental sites including teeth, alveolar bone, and gingival tissues were secured. The gingival soft tissue was processed for histomorphometric analyses at 3 levels. Epithelium and connective tissue area measurements showed no differences between the two instrumentations. Junctional epithelium (JE) cell point counts exhibited a higher proportion of inflammatory cells (IC)in specimens facing diamond compared to curet-instrumented defects. A higher proportion of IC was present within the coronal compared to the apical aspect of the JE for both instrumentations (P < 0.05). A significant difference in IC density between instrumentations was detected for non-infiltrated (P < 0.05), as well as for infiltrated (P < 0.01) connective tissue. The infiltrated connective tissue (ICT) inflammatory cell density was significantly (P < 0.01) and positively correlated to the JE inflammatory cell density (r = 0.75), and to area measurements of ICT (r = 0.55). The overall results demonstrate that the character of subgingival root instrumentations significantly affects gingival inflammatory reactions, most likely by influencing subgingival plaque formation.

Root grooves: a risk factor in periodontal attachment loss

Periodontal health reflects a balance between harmful and protective elements in the gingival margin area. The total plaque mass, specific periodontopathogens, and local environmental factors may challenge this balance. The aim of this retrospective study was to evaluate the effect of proximal root grooves as a risk factor in periodontal attachment loss. One-hundred and three (103) extracted, formalin-stored, single-rooted teeth showing loss of attachment and having one non-grooved and one grooved proximal root surface were selected for the study. Following staining in 0.1% toluidine blue to visualize attached periodontal ligament remnants, the teeth were examined in a light microscope under incident light. On each tooth, loss of attachment was measured along the long axis of the root from the cemento-enamel junction to the most coronal level of the stained periodontal ligament remnants on mesial as well as on distal surfaces. Incisors and premolars were grouped separately. For both groups, a statistically significant greater loss of attachment was present on grooved than on non-grooved surfaces (P < 0.0001). Generally, there was a direct relationship between groove location and maximum loss of attachment. The results indicate that proximal root grooves should be considered in periodontal diagnosis, prognosis, and treatment planning.