Root surface smoothness or roughness in periodontal treatment. A clinical study

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.

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.

Diamond burs versus curettes in root planing: a randomized clinical trial

BACKGROUND

This study compares diamond burs and curettes by clinical, microbiological, biochemical and scanning electron microscopic parameters and treatment time data in the non-surgical periodontal treatment of patients with chronic periodontitis.

METHODS

Two quadrants of each of the 12 patients received root planing with diamond burs, whereas the other two quadrants were treated with curettes. Clinical periodontal measurements were recorded at baseline and then 1, 3 and 6 months after completion of non-surgical periodontal treatment. Subgingival plaque and gingival crevicular fluid samples were obtained at baseline and 1-month control. Twenty-one hopeless teeth received root planing with diamond burs or curettes or no treatment and then extracted for microscopic evaluations.

RESULTS

Clinical periodontal parameters improved similarly with both treatment modalities. Microbiological analyses revealed similar findings for the bacterial load (16S gene copy numbers) and ratio of each bacterium to the total bacterial count at baseline and 1-month control. Cytokine levels in the gingival crevicular fluid samples exhibited differences between the two treatments. Scanning electron microscopic analyses indicated that diamond burs were better in terms of calculus removal and loss of tooth substance indices but roughness index values were better for curettes.

CONCLUSIONS

Diamond burs provide findings comparable with curettes in root planing.

Characteristics of the molar surface after removal of cervical enamel projections: comparison of three different rotating instruments

Purpose

The aim of this study was to evaluate and compare tooth surface characteristics in extracted human molars after cervical enamel projections (CEPs) were removed with the use of three rotating instruments.

Methods

We classified 60 extracted molars due to periodontal lesion with CEPs into grade I, II, or III, according to the Masters and Hoskins’ criteria. Each group contained 20 specimens. Three rotating instruments were used to remove the CEPs: a piezoelectric ultrasonic scaler, a periodontal bur, and a diamond bur. Tooth surface characteristics before and after removal of the projections were then evaluated with scanning electron microscopy (SEM). We analyzed the characteristics of the tooth surfaces with respect to roughness and whether the enamel projections had been completely removed.

Results

In SEM images, surfaces treated with the diamond bur were smoothest, but this instrument caused considerable harm to tooth structures near the CEPs. The piezoelectric ultrasonic scaler group produced the roughest surface but caused less harm to the tooth structure near the furcation. In general, the surfaces treated with the periodontal bur were smoother than those treated with the ultrasonic scaler, and the periodontal bur did not invade adjacent tooth structures.

Conclusions

For removal of grade II CEPs, the most effective instrument was the diamond bur. However, in removing grade III projections, the diamond bur can destroy both adjacent tooth structures and the periodontal apparatus. In such cases, careful use of the periodontal bur may be an appropriate substitute.

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.

Rotary instruments in the treatment of chronic periodontitis: A randomized clinical trial

Background:

The study aimed at comparing the effectiveness of rotary instruments with hand instruments in non-surgical treatment of chronic periodontitis.

Materials and Methods:

Thirty-eight patients with chronic periodontitis, enrolled to this randomized, controlled clinical trial, were divided into two groups. Patients in the control group received scaling and root planing with hand instruments, whereas patients in the test group received treatment with rotary instruments. Clinical assessment by plaque index, bleeding on probing, probing depth, gingival recession, and clinical attachment level was made prior to and at 6 months after treatment. Differences in the clinical parameters were analyzed using the Wilcoxon signed rank test and Mann–Whitney U test.

Results:

Both treatments resulted in a significant improvement in all clinical recordings, but no differences in any of the investigated parameters were observed at baseline between the two groups.

Conclusion:

Non-surgical periodontal therapy with the tested rotary instruments may lead to clinical improvements comparable to those obtained with conventional hand instruments.

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.

Sonic and ultrasonic scalers in periodontal treatment: a review

Periodontal therapy aims at arresting periodontal infection and maintaining a healthy periodontium. The periodic mechanical removal of subgingival microbial biofilms is essential for controlling inflammatory periodontal disease. Mechanical periodontal therapy consists of scaling, root planing and gingival curettage. The sonic and ultrasonic scalers are valuable tools in the prevention of periodontal disease. The vibration of scaler tips is the main effect to remove the deposits from the dental surface, such as bacterial plaque, calculus and endotoxin. However, constant flushing activity of the lavage used to cool the tips and cavitational activity result in disruption of the weak and unattached subgingival plaque. The aim of the study was to review the safety, efficacy, role and deleterious side-effects of sonic and ultrasonic scalers in mechanical periodontal therapy.

A comparison of root surface instrumentation using two piezoelectric ultrasonic scalers and a hand scaler in vivo

BACKGROUND AND OBJECTIVE

This study compared the effectiveness of two piezoelectric ultrasonic scalers and a hand scaler for subgingival scaling and root planing in vivo.

MATERIAL AND METHODS

Fifteen patients with advanced periodontal disease and with teeth scheduled for extraction were selected for this study. Three experimental groups of 10 teeth each were treated with one of two piezoelectric ultrasonic scalers [Vector scaler and Enac scaler] or with a hand scaler. Instrumentation was continued until the root surface felt hard and smooth to an explorer tip. The root surface characteristics after instrumentation were examined using scanning electron microscopy, and the amount of remaining calculus, roughness and loss of tooth substance were estimated using the remaining calculus index and roughness loss of tooth substance index.

RESULTS

The remaining calculus index did not differ significantly among the three groups. The roughness loss of tooth substance index was significantly lower for the Vector scaler and Enac scaler groups than for the hand scaler group and also differed significantly between the Vector scaler and Enac scaler groups.

CONCLUSION

This study suggests that the Vector scaler produces a smooth root surface with minimal loss of tooth substance. It is a reasonable choice for gentle periodontal maintenance treatment.

Effect of Er:YAG and Diode lasers on the adhesion of blood components and on the morphology of irradiated root surfaces

OBJECTIVE

The aim of this study was to evaluate in vitro, by scanning electron microscopy (SEM), the adhesion of blood components on root surfaces irradiated with Er:YAG (2.94 microm) and GaAlAs Diode (808 nm) lasers and the effects on the morphology of irradiated root surfaces.

METHODS

One hundred samples of human teeth were obtained. They were previously planed and scaled with manual instruments and divided into five groups of 20 samples each: G1 (control group) - absence of treatment; G2--Er:YAG laser (7.6 J/cm2); G3--Er:YAG laser (12.9 J/cm2); G4--Diode laser (90 J/cm2) and G5--Diode laser (108 J/cm2). After these treatments, 10 samples of each group received a blood tissue but the remaining 10 did not. After laboratory treatments, the samples were obtained by SEM, the photomicrographs were analysed by the score of adhesion of blood components and the results were statistically analysed (Kruskall-Wallis and Mann-Whitney test).

RESULTS

In relation to the adhesion of blood components, the study showed no significant differences between the control group and the groups treated with Er:YAG laser (p = 0.9633 and 0.6229). Diode laser radiation was less effective than control group and Er:YAG laser radiation (p < 0.01).

CONCLUSIONS

None of the proposed treatments increased the adhesion of blood components in a significant way when compared to the control group. Although the Er:YAG laser did not interfere in the adhesion of blood components, it caused more changes on the root surface, whereas the Diode laser inhibited the adhesion.

Effect of Er:YAG Laser on Diseased Root Surfaces: An In Vivo Study

BACKGROUND

The aim of the present study was to observe in vivo the effects of two different power settings of an Er:YAG laser on pockets of periodontally involved root surfaces using a scanning electron microscope (SEM).

METHODS

Thirty-two teeth with severe periodontal disease scheduled for extraction were divided into three groups: group A was irradiated with an energy of 140 mJ, 10 Hz; group B with 160 mJ 10 Hz; group C was used as controls. Morphological changes on the treated root surfaces were evaluated using SEM observations to assess laser-induced ultrastructural changes.

RESULTS

All surfaces treated in both groups showed a homogeneous and smooth root surface morphology. The surface alterations were very similar with both energy values used.

CONCLUSION

Er:YAG laser irradiation performed with two different power settings of root surfaces in vivo showed at the SEM observation a complete absence of debris and smooth root surfaces.

Er:YAG Laser in Defocused Mode for Scaling of Periodontally Involved Root Surfaces: An In Vitro Pilot Study

BACKGROUND

The Er:YAG laser may be used on periodontally involved teeth in combination with conventional periodontal therapy in order to improve the efficacy of root instrumentation. The aim of this study was to compare the effect of hand instrumentation on root surfaces of periodontally involved teeth with Er:YAG laser application.

METHODS

Thirty freshly extracted, non-carious, single-rooted, periodontally diseased human teeth from adult humans with advanced periodontal disease were used in this study. The teeth were divided into three groups of 10 specimens each. Group A was treated with scaling and root planing (SRP) with curets only (control). In group B, the root surfaces were scaled with curets and then lased with an Er:YAG laser (wavelength 2.94 microm). A handpiece with a water spray was used in non-contact mode (defocused) at a distance of 1 cm from root surface. Laser parameters were set at energy of 100 to 200 mJ/pulse, with 10 Hz of frequency. In group C, the root surfaces were lased only with power settings 250 to 300 mJ/pulse and 10 Hz frequency. An epon-araldite plastic embedding technique was used for light microscopic investigation.

RESULTS

Histologic findings showed significant differences between the test and control sites. In control sites, after hand instrumentation, the surface was smooth, without a cementum layer, and the dentin layer presented opened tubules. Defects on the dentin layer were also present along root surfaces. In the test sites (B, C) root surfaces revealed no thermal damage; no cracking or tissue carbonization were observed. The superficial layers of lased surfaces appeared smooth and melted without alterations.

CONCLUSION

Based on these findings, it appears that it may be feasible to use the Er:YAG laser for root instrumentation without prior root planing if the proper parameters are followed.

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.

Effect of ER:YAG and diode laser irradiation on the root surface: morphological and thermal analysis

BACKGROUND

The aim of the present study was to compare the effects of Er:YAG and diode laser treatments of the root surface on intrapulpal temperature after scaling and root planing with hand instruments.

METHODS

Fifteen extracted single-rooted teeth were scaled and root planed with hand instruments. The teeth were divided into 3 groups of 5 each and irradiated on their buccal and lingual surfaces: group A: Er:YAG laser, 2.94 microm/100 mJ/10 Hz/30 seconds; group B: diode laser, 810 nm/1.0 W/0.05 ms/30 seconds; group C: diode laser, 810 nm/1.4 W/0.05 ms/30 seconds. The temperature was monitored by means of a type T thermocouple (copper-constantan) positioned in the pulp chamber to assess pulpal temperature during and before irradiation. Afterwards, the specimens were longitudinally sectioned, and the buccal and lingual surfaces of each root were analyzed by scanning electron microscopy.

RESULTS

In the Er:YAG laser group, the thermal analysis revealed an average temperature of -2.2 +/- 1.5 degrees C, while in the diode laser groups, temperatures were 1.6 +/- 0.8 degrees C at 1.0 W and 3.3 +/- 1.0 degrees C at 1.4 W. Electronic micrographs revealed that there were no significant morphological changes, such as charring, melting, or fusion, in any group, although the specimens were found to be more irregular in the Er:YAG laser group.

CONCLUSIONS

The application of Er:YAG and diode lasers at the utilized parameters did not induce high pulpal temperatures. Root surface irregularities were more pronounced after irradiation with an Er:YAG laser than with a diode laser.

Clinical evaluation of an Er:YAG laser combined with scaling and root planing for non-surgical periodontal treatment. A controlled, prospective clinical study

OBJECTIVES

The purpose of the present controlled clinical trial was to compare the treatment of advanced periodontal disease with a combination of an Er:YAG laser (KEY II, KaVo, Germany) and scaling and root planing with hand instruments (SRP) to laser alone.

MATERIAL AND METHODS

Twenty healthy patients with moderate to advanced periodontal destruction were randomly treated in a split-mouth design with a combination of an Er:YAG laser and SRP (test) or with laser (control) alone. The used energy setting for laser treatment was 160 mJ/pulse at a repetition rate of 10 Hz. Prior to treatment and 3, 6 and 12 months later the following parameters were evaluated by a blinded examiner: Plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR) and clinical attachment level (CAL). Subgingival plaque samples were taken at each appointment and analysed using darkfield microscopy for the presence of cocci,-non-motile rods, motile rods and spirochetes. No statistical significant differences in any of the investigated parameters between both groups were observed at baseline.

RESULTS

Initially, the plaque index was 1.0 +/- 0.6 in both groups. At the 3-month examination the plaque scores were markedly reduced and remained low throughout the study. A significant reduction of the GI and BOP occurred in both groups after 3, 6 and 12 months (P < 0.05, P < 0.05, respectively). The mean PD decreased in the test group from 5.2 +/- 0.8 mm at baseline to 3.2 +/- 0.8 mm after 12 months (P < 0.05) and in the control group from 5.0 +/- 0.7 mm at baseline to 3.3 +/- 0.7 mm after 12 months (P < 0.05). The mean CAL decreased in the test group from 6.9 +/- 1.0 mm at baseline to 5.3 +/- 1.0 mm after 12 months (P < 0.05) and in the control group from 6.6 +/- 1.1 mm at baseline to 5.0 +/- 0.7 after 12 months (P < 0.05). Both groups showed a significant increase of cocci and-non-motile rods and a decrease in the amount of motile rods and spirochetes.

CONCLUSION

In conclusion, the present results have indicated that: (i) non-surgical periodontal therapy with both an Er:YAG laser + SRP and an Er:YAG laser alone may lead to significant improvements in all clinical parameters investigated, and (ii) the combined treatment Er:YAG laser + SRP did not seem to additionally improve the outcome of the therapy compared to Er:YAG laser alone.

Clinical significance of non-surgical periodontal therapy: an evidence-based perspective of scaling and root planing

Analysis of Egyptian hieroglyphics and medical papyri indicate that non-surgical periodontal treatment was common 3000-4000 years ago. Even today, scaling and root planing (SRP) remains an essential part of successful periodontal therapy. The collective evidence from numerous clinical trials reveals a consistency of clinical response in the treatment of chronic periodontitis by SRP using manual, sonic, or ultrasonic instrumentation. Thus, SRP remains the 'gold standard' to which more recently developed therapeutic modalities must be compared. Inherent to the clinical evaluation of SRP are such concerns as manual versus sonic and ultrasonic instrumentation, control of sub-gingival bacterial populations, removal of calculus, root smoothness and changes in various clinical parameters, e.g. probing depth, attachment levels, bleeding on probing and gingival inflammation. Lastly, an abbreviated discussion is presented on a relatively new paradigm of complete mouth 'disinfection' in a compressed time-frame that includes SRP as a significant component of the treatment regimen.

Effect of an Er:YAG laser on periodontally involved root surfaces: an in vivo and in vitro SEM comparison

BACKGROUND AND OBJECTIVE

The recently introduced Er:YAG laser seems to be a promising alternative in periodontal treatment due to its thermo-mechanical ablation mechanism. The present study attempted to compare the effects of an Er:YAG laser on periodontally involved root surfaces at different power settings in vivo and in vitro using scanning electron microscopic (SEM) observations.

STUDY DESIGN/MATERIALS AND METHODS

Forty single rooted teeth (160 surfaces), with advanced periodontal destruction that were scheduled for extraction, were divided into two groups of 80 each which were treated in vivo (group A) and immediately after extraction in vitro (group B) using one of the following energy settings: 120, 140, 160, and 180 mJ at 10 Hz (71, 83, 94, and 106 J/cm(2)/pulse). The morphological changes on the treated root surfaces were evaluated using scanning electron microscopic (SEM) observations to assess the laser induced ultrastructural changes. The severity of the changes was evaluated according to an arbitrary scale in 7 degrees [1-7]. Untreated peripheral areas served as control.

RESULTS

All surfaces treated in vitro (group B) showed visible crater-like defects with notch-edged borders. The depth of the surface damages varied with the power applied and was localized into cementum at energy settings of 120-160 mJ but also reached dentine at 180 mJ. Compared to that, all in vivo (group A) treated surfaces showed a homogeneous and smooth root surface morphology. The surface alterations were not related to the used energy setting.

CONCLUSIONS

The results of the present study showed that the clinical use of an Er:YAG laser resulted in a smooth root surface morphology, even at higher energy settings. The results also seem to indicate that calculus removal can be selectively done in vivo.

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.

Subgingival polishing with a teflon-coated sonic scaler insert in comparison to conventional instruments as assessed on extracted teeth (II). Subgingival roughness

AIM

To assess the root surface roughness and topography on extracted teeth using different instruments.

MATERIAL AND METHODS

In the present study, laser profilometry was used to examine the 3-D roughness values Ra and Rz and topography of root surfaces of periodontally-involved teeth instrumented in vivo with curette, conventional ultrasonic device, conventional or teflon-coated sonic scaler insert, or the Periotor instrument (12 teeth per instrument type), and compare these with uninstrumented cementum surfaces.

RESULTS

The roughness values Ra and Rz of the roots treated with the different instruments showed a similar pattern: curettes and the Periotor instrument produced the smoothest surfaces (Ra about 1.5 microm, Rz 30 microm); the 4 other instruments created similar Ra values of approximately 2-3 microm and Rz roughness of about 50-70 microm, which equals the untreated root surface. For Ra, the difference between the curette or the Periotor instrument and the teflon-coated sonic insert or ultrasonic insert was significant, and for Rz, a significant difference was found between the curette or the Periotor instrument and ultrasonic insert. As opposed to surfaces debrided with the Periotor and teflon-coated sonic scaler, it appears that hand instruments markedly reconfigure surfaces.

CONCLUSION

The lowest root-surface roughness values were obtained with hand instruments. The teflon tubing on the sonic scaler insert effected no change of topography or roughness as compared to uninstrumented, control surfaces. However, it must be pointed out that hard-tissue removal was not investigated.

Periodontal treatment with an Er: YAG laser compared to scaling and root planing. A controlled clinical study

BACKGROUND

The aim of the present study was to compare the effectiveness of an Er:YAG laser to that of scaling and root planing for non-surgical periodontal treatment.

METHODS

Twenty patients with moderate to advanced periodontal destruction were treated under local anesthesia and the quadrants were randomly allocated in a split-mouth design to either Er:YAG laser using an energy level of 160 mJ/pulse and 10 Hz or scaling and root planing (SRP) using hand instruments. Clinical assessments of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were made prior to and at 3 and 6 months after treatment. Subgingival plaque samples were taken at each appointment and analyzed using darkfield microscopy for the presence of cocci, non-motile rods, motile rods, and spirochetes. Differences in clinical parameters and prevalence of bacterial species were analyzed using the paired t-test.

RESULTS

The PI remained nearly unchanged while a significant reduction of the GI occurred in both groups after 6 months (P < or =0.001, P< or =0.001, respectively). The mean value of BOP decreased in the laser group from 56% at baseline to 13% after 6 months (P < or =0.001) and in the SRP group from 52% at baseline to 23% after 6 months (P < or =0.001). The mean value of the PD decreased in the laser group from 4.9+/-0.7 mm at baseline to 2.9+/-0.6 mm after 6 months (P< or =0.001) and in the SRP group from 5.0+/-0.6 mm at baseline to 3.4+/-0.7 mm after 6 months (P < or =0.001). The mean value of the CAL decreased in the laser group from 6.3+/-1.1 mm at baseline to 4.4+/-1.0 mm after 6 months (P < or =0.001) and in the SRP group from 6.5+/-1.0 mm at baseline to 5.5+/-1.0 after 6 months (P < or =0.001). The reduction of the BOP score and the CAL improvement was significantly higher in the laser group than in the SRP group (P < or =0.05, P < or =0.001, respectively). Both groups showed a significant increase of cocci and non-motile rods and a decrease in the amount of motile rods and spirochetes.

CONCLUSIONS

An Er:YAG laser may represent a suitable alternative for non-surgical periodontal treatment.

Root substance removal with Er:YAG laser radiation at different parameters using a new delivery system

BACKGROUND

The recently introduced Er:YAG laser radiation appears to be a promising alternative in treating dental hard tissue due to its thermo-mechanical ablation properties and the lack of thermal side effects. The present in vitro study attempted to evaluate the use of Er:YAG laser radiation in combination with a specially developed delivery system in removing calculus from root surfaces.

METHODS

Fifty extracted anterior teeth, premolars and molars, were divided into 2 groups of 25 each with (group A) and without (group B) subgingival calculus. Source of radiation was an Er:YAG laser device with a wavelength of 2.94 microm, in the infrared optical spectrum, a pulse duration of 250 ns, and a pulse repetition rate of 15 pps. In each group, 6 teeth were irradiated with 300 laser pulses either at 60 mJ, 80 mJ, 100 mJ, or 150 mJ. The samples were continually moved linearly using a computer numeric controlled device. The volumetric evaluation of root substance removal was performed with a 3-dimensional laser scanning system (100,000 surface points per sample, accuracy: 5 microm) and special image analyzing software. A scanning electron microscopic (SEM) observation was performed to assess the laser induced ultrastructural changes on the root surfaces. Statistical analysis was carried out with ANOVA followed by the Scheff*e test and with regression analysis according to Pearson-Bravais at a level of significance of 5% (P <0.05).

RESULTS

The linear measurement of substance removal on calculus samples (group A) revealed average depths between 174.38 (+/-16.13) microm and 501.85 (+/-111.01) microm. Defect depths on the teeth without calculus (group B) ranged from 37.78 (+/-14.03) microm to 484.44 (+/-80.63) microm. The SEM observation of laser-treated root surfaces revealed no signs of thermal damage; e.g., melting, fusion, or cracking.

CONCLUSIONS

The results of the present study showed that a substance removal with Er:YAG laser radiation at lower energy densities is comparable, in effect, to that after conventional root surface instrumentation with curets. The results seem to indicate that calculus removal can be selectively done using lower radiation energies. Considering the favorable results of the SEM investigation, the use of the Er:YAG laser in periodontal therapy may be possible in the future.

The effectiveness of different root debridement modalities in open flap surgery

It is unclear what degree of roughness or smoothness result from use of hand instruments alone in comparison to the use of hand instruments in combination with other aids and how it may effect the grade of cleanliness. The aim of this study was to determine in vivo whether the combination of hand instruments with other aids can increase the effectiveness of root debridement. 11 patients with holpless 4 mandibular incisors were involved in this study. After elevating a lingual and buccal mucoperiosteal flap, the 4 incisors were randomly treated with either: (1) no treatment (control); (2) 5-min scaling (method 1); (3) 4-min scaling and 1 min instrumentation with a perio-diamond bur (15 microm) (method 2); (4) 3-min scaling, 1-min instrumentation with a perio-diamond bur (15 microm) and 1 min with an air abrasive system (method 3). The cleanliness of the surface was determined using the method of Eschler and -Rapley. The degree of roughness (Ra and Rt) were measured with a laser beam (computer supported optical surface sensor system). In addition, an SEM analysis was performed. With regard to the remaining calculus (surface cleanliness), method 3 yielded significantly better results than the other 2 methods. The roughness analyses also exhibited that method 3 is superior to methods 1 and 2. The qualitative results of the SEM investigations demonstrated the most homogeneous and smooth surfaces with method 3. Root debridement in vivo was most significant using a combination of different treatment modalities (i. e., curettes, perio-diamond bur and air abrasive system).

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.

Root surface removal with diamond-coated ultrasonic instruments: an in vitro and SEM study

Adequate root preparation in periodontal procedures includes the removal of plaque, calculus, and perhaps contaminated cementum and dentin. The purpose of this study was to evaluate and compare the amount of root surface removal and residual surface texture using similarly shaped regular (US) and both fine (FINDIAM) and medium (MEDDIAM) grit diamond-coated ultrasonic inserts. Forty-five (45) premolars extracted for orthodontic reasons were randomly divided into 3 groups of 15 teeth each. They were individually mounted in a jig and instrumented with a standardized 500 gram force while they were moved a precise horizontal distance of 12 mm over a 1.2 second period using specially designed and computer controlled instrumentation. Three measurements were made to the nearest 0.0005" at 3 points along the test area before instrumentation and after 10 and 20 strokes. The mean depth of root structure removed was US 5.8 +/- 6.6 microns, FINDIAM 50.1 +/- 14.2 microns, MEDDIAM 30.8 +/- 12.1 microns, after 10 strokes, and US 12.7 +/- 10.9 microns, FINDIAM 83.3 +/- 20.1 microns, MEDDIAM 58.7 +/- 17.9 microns after 20 strokes, respectively. All 3 instruments were different from each other (P < 0.001) in the 10 stroke group, while in the 20 stroke group FINDIAM and MEDDIAM were different from US (P < 0.001), but not from each other. Only FINDIAM showed a significant difference between 10 and 20 stroke values for depth of root removal. Modified loss of tooth substance index SEM scores indicated increasingly greater root surface roughness from US to FINDIAM to MEDDIAM. Substantially greater root surface removal and greater residual root surface roughness occurred with diamond-coated ultrasonic inserts under standardized in vitro conditions. These results suggest that caution should be used with diamond-coated ultrasonic instruments during periodontal root planing procedures.

Root surface smoothness or roughness following open debridement. An in vivo study

Consensus has not been reached on the desired characteristics of the root surface following cleaning. It is also not clear what degree of roughness or smoothness results from use of different instruments. In the present human clinical study, various instruments for root surface cleaning were evaluated. 18 teeth destined for extraction for periodontal reasons were utilized. After reflection of soft tissue flaps, the 72 root surface aspects of the 18 teeth were uniformally treated with one of the following instruments: Gracey curette (GC), piezo ultrasonic scaler (PUS), Perioplaner curette (PPC), sonic scaler (SS), 75 microns diamond (75 D) and 15 microns diamond (15.D). The degree of roughness of each surface was measured after extraction. A planimetry apparatus was used to establish the average surface roughness (Ra) and the mean depth of the roughness profile (Rz). It was demonstrated that hand- and machine-driven curettes as well as very fine rotating diamonds created the smoothest root surfaces, while "vibrating" instruments such as sonic and ultrasonic scalers, as well as coarse diamonds, tended to roughen the root surface. Whether the root surface should be rough or smooth in order to enhance tissue healing remains an open question.

Root cleaning or root smoothing. An in vivo study

The goal of the present study was to determine whether the clinical treatment results in terms of pocket probing depth reduction and attachment gain would be different following conventional periodontal flap surgery if, on the one hand, root surfaces were smoothed after plaque and calculus removal or, on the other hand, root surfaces were first thoroughly cleaned but then intentionally roughened. 13 adult patients with moderate periodontitis participated; the same patients acted as a unit of control. Evaluations were performed on a total of 224 sites on 81 anterior and premolar teeth. On the 41 test teeth (111 sites), a coarse diamond stone was used following traditional root planing to roughen the root surfaces. The 40 control teeth (113 sites) were cleaned and planed using Gracey curettes. Measurements performed 3 and 6 months post-surgery revealed significant reductions in probing depths at both "rough" and "smooth" sites. However, no differences between the 2 methods were detected. This was true also with regard to attachment gain. We conclude that striving for root surface smoothness during periodontal surgery appears unnecessary.

The influence of surface roughness and surface-free energy on supra- and subgingival plaque formation in man. A review of the literature

In the oral cavity, an open growth system, bacterial adhesion to the non-shedding surfaces is for most bacteria the only way to survive. This adhesion occurs in 4 phases: the transport of the bacterium to the surface, the initial adhesion with a reversible and irreversible stage, the attachment by specific interactions, and finally the colonization in order to form a biofilm. Different hard surfaces are available in the oral cavity (teeth, filling materials, dental implants, or prostheses), all with different surface characteristics. In a healthy situation, a dynamic equilibrium exists on these surfaces between the forces of retention and those of removal. However, an increased bacterial accumulation often results in a shift toward disease. 2 mechanisms favour the retention of dental plaque: adhesion and stagnation. The aim of this review is to examine the influence of the surface roughness and the surface free energy in the adhesion process. Both in vitro and in vivo studies underline the importance of both variables in supragingival plaque formation. Rough surfaces will promote plaque formation and maturation, and high-energy surfaces are known to collect more plaque, to bind the plaque more strongly and to select specific bacteria. Although both variables interact with each other, the influence of surface roughness overrules that of the surface free energy. For the subgingival environment, with more facilities for microorganisms to survive, the importance of surface characteristics dramatically decreases. However, the influence of surface roughness and surface-free energy on supragingival plaque justifies the demand for smooth surfaces with a low surface-free energy in order to minimise plaque formation, thereby reducing the occurrence of caries and periodontitis.

Influence of tooth instrumentation roughness on subgingival microbial colonization

This study evaluated microbial colonization of periodontal pockets subjected to root instrumentation with a curet or a rotating diamond. Ten maxillary and 10 mandibular subgingival pockets were established in the canines of 5 beagle dogs. The subgingival root surface areas were debrided by a sharp curet or a flame-shaped, fine-grained, rotating diamond point. The dogs were fed a plaque-inducing diet for 70 days. Specimens from both instrumentation groups were then harvested and prepared for stereomicroscopic and scanning electron microscopic evaluation. Grading of the extent of subgingival colonization was performed in coded specimens directly on the fluorescent screen of the scanning electron microscope in a grid-counting system. Error of the method was assessed by duplicate counts. The subgingival root surface areas were divided into 3 zones: cervical, middle, and apical, and statistical differences between these zones as well as between the 2 instrumentation groups were calculated. The results revealed that curet-treated surfaces were smoother and promoted less subgingival colonization than diamond-treated surfaces. The difference in amount of bacterial colonization between the 2 groups was statistically significant (P < 0.05) in all zones. Bacterial colonization decreased in apical direction in both instrumentation groups. For the diamond-treated specimens, this decrease was significant (P < 0.05) between each of the 3 zones. In the curet-treated specimens, the decrease was significant only between the cervical and the apical zone (P < 0.05). The present study has demonstrated that subgingival instrumentation roughness significantly influences the subgingival microbial colonization.

The periodontally-involved root surface

Recent years have seen much research on the periodontally-involved root surface. Many of these studies have produced results which suggest that plaque contaminants of the root surface are only superficially placed, and capable of being removed by gentle means. Further research has attested to the difficulties in rendering periodontally-involved root surfaces free of calculus deposits by instrumentation, yet clinical studies show that periodontal disease can be managed by root planing. It is concluded that root surface debridement is best assessed on the basis of the healing response and that it should aim to disrupt plaque on and remove plaque from the periodontally-involved root surface rather than to remove part of the root surface itself.

A preliminary study on the effects of the Nd:YAG laser on root surfaces and subgingival microflora in vivo

The purpose of this study was to examine the effects of root preparation using the pulsed Nd:YAG laser, either alone or in combination with manual instrumentation. Study specimens consisting of 18 teeth with associated periodontal pockets from 8 different patients were treated as follows: 5 specimens were root planed with curets followed by laser exposure for 3 minutes using energy settings of 3.0 W at 20 pps; 2 specimens were root planed and then laser treated for 3 minutes using settings of 2.25 W and 20 pps; 4 specimens were treated by laser for 1 minute at settings of 1.75 W and 20 pps followed by root planing; 4 specimens were treated by laser only for 1 minute using settings of 1.75 W and 20 pps; and the remaining 3 teeth served as untreated controls. Both prior to and after completion of the laser and root planing treatments, microbiological samples were obtained from the treated pockets and submitted to a commercial laboratory for analysis of levels of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia. With the exception of two 7-day specimens, all others were extracted immediately post-therapy and processed for SEM examination. All treated specimens, regardless of treatment sequence, exhibited some degree of laser-induced root surface alteration. Notably, laser-treated calculus deposits were free of their characteristic surface layer of microbial plaque. Microbial sampling indicated a post-therapy reduction in levels of all 3 putative microbial pathogens compared to pre-treatment samples and control specimens. However, SEM examination revealed residual deposits of plaque and calculus in all treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of ultrasonic debridement of calculus-associated periodontally-involved root surfaces by the limulus amoebocyte lysate assay. An in vitro study

This investigation assessed the effectiveness of an in vitro ultrasonic debridement regime on periodontally involved teeth with visually-detectable calculus deposits, using the LAL assay for lipopolysaccharides (LPS) as a marker of bacterial products. 34 single rooted teeth with extensive amounts of calcified accretions were selected, of which 10 served as uninstrumented controls for the estimation of existing LPS levels. The periodontally involved roots of the 24 experimental teeth were debrided with a Cavitron TF-10 tip for a limited time using light pressure and overlapping strokes which ensured complete surface instrumentation without reference to the presence of calculus. Marked reductions in root surface area coverage by calculus were nevertheless achieved as assessed planimetrically from photographic records of the teeth before and after debridement. The root surfaces of each tooth were then stripped away and the harvested material subjected to 'Westphal' extraction and LAL assay for LPS. The resulting LPS yields from the experimental teeth ranged from less than 0.08 to 22.387 ng compared to 1,900 to 29,200 ng from the uninstrumented controls. The extremely small residual LPS yields from the experimental teeth not only confirm the efficacy of ultrasonic debridement but, when coupled with the lack of a relationship with the widely varying amounts of the remaining calculus, support the contention that bacterial plaque rather than calculus has the greater pathogenic potential. These results reinforce the growing impression of the superficial location of bacterial toxic products associated with periodontally involved root surfaces.

A scanning electron micrographical study of root surfaces and subgingival bacteria after hand and ultrasonic instrumentation

The effects of hand and ultrasonic instrumentation on root surface topography and subgingival plaque were studied. One approximal subgingival root surface on each of two single rooted teeth of six patients was root planed. The opposing proximal surfaces were not treated and served as controls. On each patient, the two test surfaces were randomly treated by hand or ultrasonic instrumentation (Cavitron) until clinically smooth. The teeth were extracted, divided into mesial and distal sides, and processed for scanning electron microscopy (SEM). The observations were restricted to an area 2 mm by 3 mm just coronal to the plaque-free zone. The root surfaces were scanned by SEM, both at low (x 100) and at higher magnifications (x 5000). At low power, a photomontage was produced of the surface area of the test teeth. At low magnifications (x 100, x 500), the topography resulting from hand instrumentation appeared smooth with parallel scratches compared to scaly but flat surfaces with occasional deep gouges with the ultrasonic method. At high magnifications (x 5000), tooth surfaces were similar in topography when instrumented by either hand or ultrasonic methods. Root surfaces were covered in some areas by a fibrillar-like membrane that resembled fibrin. Individual bacteria were found on the surfaces of this material. On other areas not covered by this membrane, bacterial plaque was only observed when tooth surfaces had not been contacted by either hand or ultrasonic instrumentation.

The impact of research on scaling and root planing

The research expanding our knowledge of the periodontally involved root surface and its treatment is reviewed. To improve communication in the clinic and classroom, definitions are suggested for the terms "scaling" and "root planing." The objective and limitations of root planing procedures are discussed.

The effectiveness of hand versus ultrasonic instrumentation in open flap root planing

The primary purpose of the study was to determine if, with an open flap approach, ultrasonic or hand instrumentation could remove all calculus from previously untreated teeth with moderate to severe loss of attachment. To be included in the study, teeth had to have at least 5 mm of attachment loss, be scheduled for extraction and be graded 2 or 3 on the Calculus Index of the Periodontal Disease Index system. Under local anesthesia, full-thickness, envelope-type flaps were elevated apical to the crest of bone to allow access to the root surfaces which were then treated with hand or ultrasonic instrumentation until the roots felt hard and smooth to a Hartzell explorer. The teeth were then removed, rinsed, and lightly scrubbed to remove debris and a No. 14 wheel bur was used to place a groove along the coronal extent of the connective tissue attachment. A stereomicroscope at magnification X 4.6 was used to quantitate the percentage of residual calculus on 25 teeth treated by each method. Overall, hand-scaled root surfaces demonstrated less residual calculus (5.78%) than ultrasonically treated surfaces (6.17%). Twenty teeth treated by each method were then prepared for histologic evaluation and evaluated under the light microscope at magnification X 100 for residual calculus and relative smoothness. Residual calculus was found on four ultrasonically and 12 hand-treated teeth and was almost evenly distributed between anterior and posterior teeth for both methods. The finding of considerably less calculus on histologic than on stereomicroscopic examination may have been due to the loosening of deposits by instrumentation, especially ultrasonic vibration, and their subsequent release during histologic preparation.(ABSTRACT TRUNCATED AT 250 WORDS)