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Aims: To explore the influence of gender on periodontal treatment outcomes in a dataset of eight RCTs conducted in Brazil, United States, and Germany., Methods: Clinical parameters were compared between men and women with stages III/IV grades B/C generalized periodontitis at baseline and 1-year post-therapy, including scaling and root planing with or without antibiotics., Results: Data from 1042 patients were analyzed. Men presented a tendency towards higher probing depth (p = .07, effect size = 0.11) and clinical attachment level (CAL) than women at baseline (p = .01, effect size = 0.16). Males also presented statistically significantly lower CAL gain at sites with CAL of 4-6 mm at 1-year post-therapy (p = .001, effect size = 0.20). Among patients with Grade B periodontitis who took antibiotics, a higher frequency of women achieved the endpoint for treatment (i.e., ≤4 sites PD ≥5 mm) at 1 year than men (p < .05, effect size = 0.12)., Conclusion: Men enrolled in RCTs showed a slightly inferior clinical response to periodontal therapy in a limited number of sub-analyses when compared to women. These small differences did not appear to be clinically relevant. Although gender did not dictate the clinical response to periodontal treatment in this population, our findings suggest that future research should continue to explore this topic., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: The aim was to identify benefit thresholds for clinical variables. We hypothesize, if variables fall below or exceed these threshold levels, systemic amoxicillin/metronidazole may contribute to reducing progression of periodontitis., Material & Methods: This is an explorative per-protocol collective analysis (n = 345) conducted on the placebo-controlled, multi-centre ABPARO trial (ClinicalTrials.gov NCT00707369). Patients received debridement with systemic amoxicillin 500 mg/metronidazole 400 mg (3×/day, 7 days, n = 170) or placebo (n = 175) and maintenance therapy every three months. To identify thresholds, each of the following baseline characteristics was classified into two groups (≥threshold value/ 5 mm (5.2%) at baseline compared to the placebo (9.0%, 11.6%, and 12.5%, respectively; p < 0.005)., Conclusions: The clinical benefits of systemic amoxicillin/metronidazole may depend on periodontitis severity and patients' age., (© 2019 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.)

Background: Residual probing depth (PD) after subgingival scaling can be treated with repeated scaling or periodontal surgery. Ambiguous results about the additional clinical benefit of a second scaling procedure exist. Therefore, we performed a prospective study comparing the clinical results of repeated subgingival scaling versus periodontal surgery in 30- to 40-year-old subjects with generalized advanced periodontitis., Methods: Twenty-six subjects (mean age, 37 +/- 3 years) were treated after an initial examination (t(1)), initial subgingival scaling, and baseline examination (t(2)) with a randomly assigned second subgingival scaling (test) and periodontal surgery (control) in a split-mouth design. The final examination (t(3)) took place 6 months postoperatively. Intraindividual comparisons of mean PD and clinical attachment level (CAL) were analyzed., Results: PD was reduced from 4.1 +/- 0.2 mm initially (t(1)) to 3.1 +/- 0.1 mm at baseline (t(2)), and to 2.9 +/- 0.1 mm at the end of the study (t(3)) for the test sites; and from 4.5 +/- 0.2 mm (t(1)) to 3.5 +/- 0.1 mm (t(2)), and 3.1 +/- 0.1 mm (t(3)) for the control sites. The total PD decrease from t(1) to t(3) was significant (P <0.001) for both therapies. PD reduction from t(2) to t(3) was only significant (P <0.001) for control sites, resulting in a significant (P = 0.010) difference between test and control at the final examination. CAL increased 0.2 +/- 0.1 mm (t(2)) plus 0.3 +/- 0.1 mm (t(3)) for the test sites and 0.2 +/- 0.1 mm (t(2)) plus 0.2 +/- 0.1 mm (t(3)) for the control sites. Total CAL gain was statistically significant for the test and control sites. CAL gain from t(2) to t(3) was only significant (P = 0.022) for the test sites., Conclusions: Both treatments reduced PD and increased CAL. A second subgingival scaling resulted in significant additional CAL gain and reduced the need for surgery.

Aim: We have recently tested a surface detection system based on a conventional dental ultrasonic scaler in vitro. The aim of the present study was to investigate sensitivity and the specificity of the detection device in vivo., Material and Methods: Subgingival buccal surfaces of 63 arbitrarily selected periodontally compromised teeth were scanned intra-orally, while the supragingival positions of the insert, along with the corresponding signals of the detection system, were saved as separate files. After extraction, the surface detection results were evaluated by re-positioning the inserts' position on the tooth in vitro and comparing the detection results with visual findings., Results: On the scanned tooth surfaces, there were 44 calculus spots, which covered 22.3% of all scanned surfaces (prevalence). The calculus-free surface was divided into "spots" mathematically. The device correctly classified 40 calculus and 125 cementum spots, whereas four calculus and 28 cementum spots were classified incorrectly. Calculus and cementum were discriminated with a sensitivity of 91% and a specificity of 82%. The positive and negative predictive values were 0.59 and 0.97., Conclusion: The surface detection device was able to clinically differentiate cementum and calculus in vivo. Therefore, this method may support the decision of whether continued subgingival scaling could damage the cementum.

Study Objective: The objective of subgingival instrumentation of periodontally diseased root surfaces is to remove the adhering microbial biofilm and calcified deposits. Recently, we have described an automated calculus detection system under static conditions. Clinically however, the tip of the system has to be moved over tooth surfaces. It was thus necessary to study the entire system in motion., Methods: The detection device is based on a conventional dental piezoelectric ultrasonic handpiece with a conventional scaler insert. The impulse response of the mechanical oscillation system is analysed by a fuzzy logic-based computerized algorithm, which classifies various surfaces. The present study investigates dental surface recognition properties of the new system with the tip being moved over teeth surfaces in vitro. Following a training set of 7977 measurements (3960 calculus, 4017 cement) on 200 extracted teeth, 1363 measurements were conducted on 34 teeth unknown to the system., Results: The surfaces cementum and calculus were correctly classified in 78% within the training set and in 81% within the set unknown, with a kappa value of 0.68., Conclusion: It was shown that this method of automatic recognition of tooth surfaces is able to distinguish between different tooth surfaces in vitro independently from tip movements.

Objective: Previous studies have shown that endotoxins are located on the periodontally diseased root cementum and not within it. To what extent a Teflon-tubed sonic scaler was capable of removing bacterial deposits in comparison to conventional scaling instruments, and the resulting root surface roughness and root surface topography, were recently assessed. The objective of the present study was to evaluate how much root cementum is removed with these instruments., Methods and Materials: Eighty-two teeth were treated subgingivally on one approximal site either with a Teflon-coated sonic scaler insert (tSS), a Gracey curette, a conventional sonic scaler (SS), a piezoelectric ultrasonic scaler insert (US), or an oscillating Periotor insert (PT) before extraction. The untreated site served as control. The width and length of cementum removal were compared histomorphometrically. Nonparametric analyses were carried out for statistical comparison., Results: The US, PT, and tSS inserts removed less substance than the curettes or SS inserts. The cementum removed was 40 microm for root surfaces treated with the curette or SS, 30 microm for those treated with US, 20 microm for PT, and 17 microm for tSS., Conclusion: The Teflon-coated sonic scaler inserts can be a reasonable choice for gentle maintenance treatment of compliant patients with good plaque control, and little or no subgingival deposits.

Background: Sonic scalers have an elliptical and piezoceramic ultrasonic scalers a linear oscillation pattern. Thus, a sonic scaler "hammers" the tooth surface, irrespective of its alignment to the tooth, whereas a piezoceramic ultrasonic scaler may oscillate parallel to the tooth surface and gently remove calculus if the alignment is correct. The aim of this study was to measure pain on a visual analogue scale (VAS) during removal of supragingival calculus on mandibular incisors with a sonic or an ultrasonic scaler., Material and Methods: Seventy-four periodontally healthy subjects with supragingival calculus on the mandibular incisors were treated with both a sonic and a piezoceramic ultrasonic scaler in a split-mouth design. The sequence of instrument application and allocation of instruments to jaw side were randomized. Patient comfort was assessed with a VAS after treatment., Results: The VAS results did not show any difference between the two instrumentation modalities., Conclusion: For calculus removal during prophylaxis the type of power-driven instrument does not seem to have an impact on perceived pain. This means that the oscillation pattern does not influence the pain experience.

Background: A recently introduced piezo-driven ultrasonic device (Vector) generates longitudinal oscillations. As a result, the instrument tip moves parallel to the tooth surface. By avoiding vertical oscillations, maintenance treatment with the Vector device should be less painful than treatment with conventional systems. We investigated whether patients perceive treatment with the Vector device as less painful than with a conventional ultrasonic device, and whether the clinical efficacy of the Vector device is comparable with that of the conventional ultrasonic device in maintenance patients., Material and Methods: Thirty-eight maintenance patients with moderate to advanced periodontal disease took part in this prospective, randomized controlled clinical study. Each patients had to have at least two teeth with probing depths of >4 mm. They were treated either with Dentsply (n=22) at a reduced power setting or with the Vector device (n=16). The observation period was 6 months. Probing pocket depth, attachment level, and bleeding upon probing were assessed at six sites on each treated tooth by a blinded investigator Patient were asked to report perceived pain during instrumentation with a visual analog scale immediately after treatment, in the evening of the treatment day, and in the evenings 1 and 2 days after treatment., Results: Bleeding on probing, probing depth, and attachment level improved in both instrumentation groups from baseline to month 6; however, there was no difference between the two instrumentation modalities. The patients perceived treatment with neither instrument as unpleasant, and their perception of pain intensity both during instrumentation and on the following days did not differ., Conclusion: In maintenance therapy, clinical efficacy of the vector device is comparable with that of conventional ultrasonic device. It makes no difference whether the ultrasonic device at a reduced power setting or the Vector device is used, since patients perceive both instruments as causing very little pain.

Background, Aims: In a manikin study we recently assessed how effectively student operators were able to learn scaling with curettes (GRA) and power-driven instruments (PP). Calculating the debrided root area effectiveness was low in both groups without systematic training or without a motivational program. After 10 weeks (20 h) of training, operators reached a high effectiveness of 84.7% (GRA) and 81.6% (PP). The purpose of the present study was to evaluate the clinical outcome of nonsurgical treatment as performed by these student operators., Methods: In a clinical trial, 19 students trained in the use of Gracey curettes for 10 weeks (=20 h) (GRA10) and Periopolisher system for 1 week (=2 h) (PP1), and 20 students trained in the use of Gracey curettes for 1 week (GRA1) and the Periopolisher for 10 weeks (PP10) treated one patient each in a split-mouth design. At baseline and 6 months, we recorded probing depth (PD), probing attachment level (PAL) and bleeding on probing (BOP) by computer-assisted probing. Statistical analysis was carried out for moderate (category B) and deep sites (category C). Groups were compared using Student's t-tests (p<0.05)., Results: Category B sites showed a PD reduction of 1.2/1.0 mm (GRA10/GRA1) and 1.1 mm (PP10/PP1). PAL gain was 0.5/0.3 mm (GRA10/GRA1) and 0.4/0.2 mm (PP10/PP1). In category C sites, PD reduction was 2.1/2.3 mm (GRA10/GRA1) and 2.0 mm (PP10/PP1) with a PAL gain of 0.6/0.9 mm (GRA10/GRA1) and 0.4 mm (PP10/PP1). BOP was significantly lower in all groups., Conclusion: The results show that student operators who had received a systematical training on manikins and had attained different effectiveness results were able to treat periodontally diseased patients successfully using both Gracey and Periopolisher instruments.

The influence of systematic dummy-head training with Periopolishe (PP, group A) and Gracey instruments (GRA, group B) on the effectiveness of root debridement was evaluated by Rühling et al., 2002 (9). Their results indicate that independent of the instrument used, untrained operators were only able to debride root surfaces at low levels of effectiveness. It was possible to increase effectiveness to a high level through systematic training in both groups. The aim of the present study was to assess the role of operator motivation and self-assessment on scaling effectiveness. Before baseline, operators were asked to answer a questionnaire rating the expectation of the instrument performance. Four groups of inexperienced operators (n = 11 each) received 10 weeks dummy-head training. In groups A (GRA) and B (PP), training was combined with a motivational programme. Groups C (GRA) and D (PP) received the same training, but no additional motivational programme. In a dummy-head, 10 test teeth were debrided and operators were asked to estimate their effectiveness of debridement at each test day. Effectiveness was calculated as percentage of debrided root area on 10 test teeth at different time points with an image analysis programme (NIH Image) and ANOVA. Two groups were compared using the Mann-Whitney U-test (unpaired) and the Wilcoxon signed ranks test (paired). Motivated groups (A and B) reached about 25% higher debridement results (p < 0.001) and were able to estimate their effectiveness more precisely compared to groups C and D. In the low motivation groups (C and D), overestimation of more than 20% was evident (p < 0.001). The questionnaires revealed underestimation of the GRA instruments and overestimation of PP instruments. Operator motivation and self-assessment greatly influence learning of effective root debridement.

Background/aims: In a dummy-head trial, we assessed how effectively untrained operators were able to learn scaling with curettes and power-driven instruments., Methods: Two untrained operator groups (n = 11 each) received six 2-h lessons during a 10-week period following a training program. Subgingival scaling was performed with curettes (GRA) and a power-driven system (PP). At 6 test days each subject had to instrument 10 test teeth. The percentage of debrided area was assessed with an image analysis program. Learning success was measured as a percentage of debrided root area and scaling time. Furthermore, the effectivity was related to difficulty in anatomical situations and access to root surfaces. Statistical analysis was carried out with SPSS., Results: At baseline, effectivity was 63.1% (GRA) vs. 52.3% (PP). Between weeks 9 and 11, operators reached a plateau for group GRA at 84.7% and group PP at 81.3%. Scaling time did not differ between the two groups. Debridement of teeth with complex root shapes that were hard to access was less effective with the power-driven system., Conclusion: Independent of the instrument used, untrained operators were only able to debride root surfaces at low levels of efficacy. With systematical training, effective scaling with the power- driven system was as easy to learn as with hand instruments. On root surfaces with complicated shape and anatomy or difficult accessibility, the power-driven system works significantly less effectively.

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.

Background: Recently, we have developed teflon-coated sonic scaler inserts which remove plaque without removing tooth substance; they polish subgingivally. In a preclinical test, we showed that these modified inserts remove plaque nearly as effectively as do conventional sonic scaler inserts. The present investigation was intended as a proof-of-principle of subgingival polishing. The aim was to study the effect of subgingival polishing on the resolution of gingival inflammation in comparison to conventional scaling., Material and Methods: In 10 patients with moderate to advanced periodontal disease, who had at least 2 single-rooted teeth with a probing depth of >6 mm in each quadrant, all single-rooted teeth were subjected to one treatment regimen consisting of 2 instrumentation episodes (1st/2nd treatment): curette/curette, curette/teflon-coated sonic scaler, teflon-coated sonic scaler/teflon-coated sonic scaler, and an untreated control. The second treatment session was performed 3 months after the first instrumentation, and the final registration 3 months after the second instrumentation. Clinical measurements included probing depth, change of clinical attachment level, bleeding upon probing, and plaque scores., Results: Probing depth, attachment level, and bleeding scores were reduced in the 3 instrumentation groups versus the control group in the 1st period; in the 2nd period, no further change occurred. Subgingival polishing with teflon-coated sonic scaler inserts was slightly less effective than conventional scaling., Conclusion: Subgingival polishing with teflon-coated sonic scaler inserts seems to be nearly as effective as conventional scaling. Thus, it may be the instrumentation of choice for maintenance treatment of residual pockets.

Background, Aims: Depending on the phase of periodontal treatment, power-driven inserts with different power levels are necessary: during initial treatment and flap operations, it must be possible to remove calculus which firmly adheres to the root surface with great efficiency; in contrast, gentle root-surface instrumentation has a high priority during maintenance treatment. Recently, modified sonic scaler inserts have been introduced: diamond-coated inserts for open flap operations and slim probe-shaped sonic scaler inserts for deplaqueing during maintenance., Method: We compared the substance removal by these inserts to that of a conventional insert. In a bench system which allows application force, stroke height, and width and frequency of instrumentation to be monitored and also permits assessment of the topography before and after instrumentation (yielding depth removal and removed volume), we instrumented aluminum rods in triplicate and bovine roots in a 5-fold repetition., Results: With high application forces (1.0 N), the diamond-coated inserts removed 30 to 50% more substance than the conventional one. Except for the slim inserts, there was a significant linear relationship between increasing force and removed volume. Probe-shaped inserts do not remove considerable substance even with increasing pressures., Conclusions: Diamond-coated inserts remove tooth substance very effectively and must thus be handled with care: more pressure effects more removal. Probe-shaped inserts can be used without risk during maintenance visits.

Background: Recent studies have shown that endotoxins are located on the periodontally diseased root cementum and not within it. These studies led to the suggestion that the root surface could be treated less aggressively during periodontal therapy. Thus, we designed a teflon-tubed sonic scaler insert for subgingival polishing. It was our objective to assess to which extent this new instrument is capable of removing bacterial deposits in deep pockets in comparison with conventional scaling instruments., Method: We compared the extent to which plaque and calculus could be removed with a curette, a conventional sonic and ultrasonic scaler insert, a Per-io-tor insert, and a teflon-tubed sonic scaler insert. 84 teeth requiring extraction had been treated with one of these instruments. After extraction, the teeth were stained with Malachite green, and the following areas were assessed: area lacking plaque and calculus, calculus, and area only covered with plaque. For statistical comparison, nonparametric analyses were carried out., Results: Curettes and conventional ultrasonic and sonic-scaler inserts had more area lacking plaque and calculus (97.5%, 92.2%, 92.1%) than did the Per-io-tor (80.1%) or the teflon-coated sonic scaler insert (84.4%). A similar effectivity sequence was observed for residual soft deposits (curette: 1.9%, ultrasonic scaler: 6.1%, sonic scaler: 5.4%, teflon-coated sonic scaler: 5.1% and Per-io-tor: 9.5%)., Conclusions: The Per-io-tor and the teflon-coated sonic scaler insert seem to be suitable for the removal of soft deposits on the root surface, but not for the removal of calculus.

In our laboratory, we modified sonic scaler inserts to increase effectivity of root surface instrumentation of molars with furcation involvement during flap surgery. The working end of conventional sonic scaler inserts was thickened ellipsoidally and diamond coated. Inserts with variously angled shafts were designed in order to facilitate insertion into the furcation. A clinical, split-mouth study examined the debridement of molars with furcation involvement during flap surgery using either hand instruments or diamond-coated sonic scaler inserts with 15 patients. Average treatment time was cut by ca. 50%, using diamond-coated inserts as compared to hand instruments for root surface debridement during surgery. 2 years after surgery, the clinical parameters had not been influenced by type of instrument used.

In our laboratory, we modified inserts of a sonic scaler to increase effectivity of root surface instrumentation during flap surgery. The present clinical study investigates whether use of this diamond-coated, thickened insert facilitates more rapid root debridement compared to hand instruments and whether clinical wound healing is influenced by the type of instrument used. In 13 patients with moderate to advanced periodontal destructions, flap surgery was carried out on single rooted teeth with probing depth of > or =6 mm. The mean amount of time saved by root debridement with the diamond-coated insert was 60% over curets. Regardless of the used instrumentation method probing depths and attachment level changes were altered and remained unchanged for 2 years after surgery. In conclusion the newly-developed, diamond-coated sonic scaler insert facilitates more rapid root debridement during flap surgery than hand instruments without disadvantageously affecting clinical healing.

We developed a sonic scaler tip with an ellipsoid diamond-coated bud and contra-angulated shafts to overcome problems resulting from furcation anatomy. In this study, extracted molars were instrumented in a dummy model without any replicated soft tissues using 3 different instrumentation methods (i) curettes, (ii) diamond-coated sonic scaler tips with normal handle and (iii) diamond-coated sonic scaler tips in 2 handles with varying power levels. 15 extracted upper and lower molars were instrumented using each of the 3 instrumentation types. Following debridement, loss of substance and % of furcation area instrumented were assessed. In both upper and lower molars, significantly more surface area was instrumented in one instrumentation run with diamond-coated tips than with curettes. Substance loss was greater with diamond-coated tips than with hand instruments. In conclusion, an effective debridement of the furcation roof seems only possible with odontoplasty. Clinical evaluation of this approach to root debridement is needed.

The purpose of this study was to determine the suitability of different scaling instruments for the debridement of furcations. 12 upper and 12 lower replicated molars with through-and-through furcations were instrumented 3x with 5 different types of instruments: (i) hand instruments; (ii) hand instruments in conjunction with diamond burrs; (iii) a conventional ultrasonic scaler insert; (iv) a conventional sonic scaler insert; (v) a set of 2 modified diamond coated sonic scaler inserts with different angulated shafts. The plastic replicas were fixed in a manikin head without replicated soft tissues. Following debridement, weight loss and % of instrumented furcation area were assessed. In the case of lower molars, it made little difference whether they were treated with hand instruments, hand instruments combined with diamond burrs, or diamond-coated sonic scaler inserts. On upper molars, however, significantly more area was instrumented with the diamond-coated inserts than with the other instruments. Substance removal was greater with diamond-coated inserts than with the other devices. In conclusion, an effective debridement of the furcation seems possible only with an odontoplasty, in which a furcation is fitted to the instrument by means of intensive instrumentation, thus leading to substance loss. To improve results with these instruments, further research is necessary.

The authors have developed a set of four modified sonic scaler inserts with variously shaped shafts and diamond-coated budded inserts. The inserts are specially designed for the furcation area since instruments used hitherto have not been successful in completely preventing slow continuous periodontal breakdown in multirooted teeth. To improve understanding of their clinical effectiveness, instrumentation of dentin samples was done with a curette as well as conventional and modified sonic scaler inserts under standardized conditions. The results showed that significantly greater amounts of tooth substance were removed with the diamond-coated airscaler tips than with the conventional tip. The depth of substance removal was comparable to that obtained with hand instruments and increased with application force. Although differences in surface texture were found among the different modes of scaling, it remains to be determined whether they are of clinical significance.

The authors have developed a set of four modified sonic scaler inserts with variously shaped shafts and diamond-coated budded inserts. The inserts are specially designed for the furcation area since instruments used hitherto have not been successful in completely preventing slow continuous periodontal breakdown in multirooted teeth. To test their clinical effectiveness, the displacement amplitude of the different sonic scalers was measured under varying load applications. Each scaler insert generated different and characteristic displacement amplitudes from rest position. The conventional insert was continuously dampened under increasing load application, whereas the diamond-coated inserts showed only minor variations of oscillation pattern. In a clinical situation, both insert types should be used, with the least possible application load to maintain effectiveness and minimize removal of hard tissue.

Power instrumentation of periodontally-diseased root surfaces is gaining in significance as an alternative to conventional curette methods. In an experimental study employing manikins with simulated bone loss, we investigated whether inexperienced and experienced operators were able to achieve greater therapeutic success with power-driven devices than with hand instruments in subgingival scaling. 10 dentists experienced in periodontal treatment and 10 inexperienced dentists instrumented 7 teeth in the upper jaw, which had been covered with artificial deposits. Hand instruments, the Perioplaner system, a sonic and an ultrasonic scaler were used. The time required for treatment was measured and the % of residual deposits was calculated by means of image-processing techniques. Weight loss was also determined for the teeth that were scaled with the hand instruments and the Perioplaner system. Experienced operators left significantly less % of residual deposits on the teeth (18+/-7.6%) than the inexperienced (27+/-8.4%), regardless of the type of instrument selected. Both experienced and inexperienced operators left the smallest amounts of residual deposits with hand instruments (13+/-9.8%/24+/-9.5%). Both treatment groups removed more hard tooth structure with hand instruments than with the Perioplaner system (53+/-48mg versus 47+/-25.9 mg). Experienced operators needed somewhat more time for debridement than unexperienced. Use of the sonic/ultrasonic device required somewhat less time than hand instrumentation. Inexperienced operators are, however, unable to improve their treatment results by using the power-driven instruments included in the study.

The purpose of this study was to determine the suitability of different scaling instruments for surgical removal of hard and soft bacterial deposits and for the removal of soft accretions only for maintenance treatment within furcations. 12 upper and 12 lower plastic replicated molars, with through-and-through furcations, were instrumented 3 x with 4 different types of instruments: (1) hand instruments; (2) a conventional sonic scaler insert; (3) a set of 3 modified sonic scaler inserts with budded tips and different angulated shafts; (4) a set of 3 sonic scaler inserts with a plastic-coating and different angulated shafts. The plastic replicas were fixed in a dummy head without any replicated soft tissues. In the furcation area, an easily removable surface coating material was applied to the teeth to represent the "plaque" and a second, more stubborn lacquer layer representing "calculus/cementum". Following instrumentation, the following parameters were recorded to assess efficacy; time required for instrumentation, loss of weight, depth of substance removal at the furcation entrance, % of furcation area instrumented, whereby removal of these 2 layers was judged separately. Only minor differences were observed between hand instruments, conventional and budded sonic scaler inserts as to loss of weight, depth of substance loss and area instrumented. The plastic-coated sonic scaler inserts were just as effective in surface layer removal representing "plaque" as the 3 other instruments, but resulted in less loss of weight and less depth of substance removal. In conclusion, the more aggressive hand instruments, the conventional and budded sonic scaler insert, are preferably used for the surgical phase to increased ease of entry into the furcation dome. An effective debridement of the furcation roof seems only possible with an odontoplastic, for which a furcation is fitted to the instrument by means of an intensive instrumentation, thus leading to weight loss and pronounced substance removal. The plastic-coated sonic scaler inserts seems to be a reasonable choice for maintenance treatment within furcation, since this treatment phase is usually restricted to removal of soft bacterial deposits.

It is important to know how much heat is generated when a root surface is debrided with sonic scalers and if that heat can be released satisfactorily into the environment. The temperature changes that occurred in dentinal specimens treated with two different sonic scaler tips, used with and without coolant, were studied. Temperature increases of up to 4 degrees C were observed for both tips when a coolant was used. Heat propagation during instrumentation was dependent to a considerable degree on the temperature of the coolant. Sonic scalers should not be used without coolant, because the dentinal temperature may increase up to 35 degrees C, depending on the force of application. A high positive linear correlation was found between increase in temperature and force of application.

Removal of plaque and calculus by means of sonic and ultrasonic scalers causes considerable damage to implants. With a view to avoiding the aggressive effects of these instruments, an experimental study was carried out for which conventional sonic and ultrasonic scalers were coated with Teflon. The effects of these instruments on implant surfaces was then compared with that of plastic and metal implant curettes. Stereo-microscopy, scanning electron microscopy and surface profilometry were used to detect and record damage to implant surfaces and changes in surface roughness. Generation and propagation of heat in subgingival simulation of use of sonic and ultrasonic scalers were also recorded by means of temperature measurements at the implant surface. The results revealed that no discernible damage was caused by Teflon-coated sonic and ultrasonic scalers or implant curettes made of plastic on smooth titanium surfaces. Instrument material residues were found on rough implant surfaces. It was not the intention of this study to provide an analysis of the prerequisites for the cleaning of rough implant surfaces, but rather to determine what type of damage is to be expected when contact is made with smooth and rough surfaces unintentionally. Temperature measurements during the subgingival use of sonic and ultrasonic scalers indicated satisfactory functioning of the cooling system. Coating of sonic and ultrasonic scaler tips with Teflon thus facilitates the use of high-frequency instruments to achieve professional cleaning of implants.

The present status of root surface debridement is reviewed. Recently it was shown that the influence of root surface roughness and endotoxin-contaminated cementum was overestimated. The method of instrumentation (i.e., hand instrument, sonic or ultrasonic scaler) does not influence wound healing after periodontal surgery. The operator's technique is of utmost importance.

A clinical trial examined the effect of calculus removal on the enamel surface using a Gracey curette 5/6, an ultrasound unit, and three air scalers with five different tips, in terms of the rate of surface lesions and the extent and depth of the defects. A total of 140 teeth were copied to assess and measure the surface lesions. The hand-held instrument did not damage the tooth surface. For calculus removal with automatic instruments surface lesions were observed to be a function of the type of equipment and the tip configuration used, with sharp-edged instruments causing the more severe destruction. Therefore automatic calculus removal instruments should not be used for routine tooth cleaning. They should be reserved for first-time removal of old, hard, and very tough calculus.

Rühling A, Wulf J, Schwahn C, Kocher T: Surface wear on cervical restorations and adjacent enamel and root cementum caused by simulated long-term maintenance therapy. J Clin Periodontol 2004 doi: 10.1111/j.1600-051X.2004.00482.x.© Blackwell Munksgaard, 2004. 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. 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. The results showed that POL led to slight substance loss, which was greater using Cleanic® (27 μm) than Proxyt® (5 μm). CUR+POL produced a significantly greater substance loss than did US+POL, with 186 μm versus 35 μm on glass-ionomer cement, respectively, and 123 μm versus 18 μm, respectively, on root cementum, followed by composite (111 μm versus 27 μm, respectively), polyacid modified composite resin/compomer (89 μm versus 36 μm), amalgam (75 μm versus 19 μm), and enamel (32 μm versus 23 μm). 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. [ABSTRACT FROM AUTHOR]