Antimicrobial effects of mechanical debridement Gregor J Petersilka
Antimicrobial effects of mechanical debridement Gregor J. Petersilka, Benjamin Ehmke, Thomas F. Flemmig
Patient-Performed Plaque Control
Manual and powered toothbrushing 1. The cleaning efficacy of a toothbrush correlates with brushing time and is significantly enhanced by the use of toothpaste. 2. There is, however, only a low correlation between applied pressure and brushing effectiveness.
Manual and powered toothbrushing 3. Although minor differences in the effectiveness of various toothbrushes were found, the clinical relevance of these findings is unclear. 4. Though designed primarily for the removal of supragingival plaque, the use of both powered and manual toothbrushes may allow penetration of the subgingival area to a maximum depth of about 0. 9 to 1. 5 mm.
Manual and powered toothbrushing 5. Patient motivation and oral hygiene instruction are claimed to be a major factor influencing the degree of plaque control. 6. To achieve clinically relevant reductions in plaque levels, as much as 3. 5 hours of instruction and motivation are needed.
Manual and powered toothbrushing 7. While toothbrushing may reduce the levels of periodontopathogenic bacteria such as Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis, Eikenella corrodens and Treponema denticola in supragingival plaque, it does not significantly reduce the percentage of subgingival sites infected with these pathogens even when toothbrushing is combined with supragingival scaling.
Fig 1. Effectiveness of supragingival plaque removal using manual or powered toothbrushes
Interdental hygiene 1. Interdental (directly under the contact area) or interproximal areas (visible spaces between the teeth, which are not under the contact area) cannot be cleaned by toothbrushing alone. 2. It is therefore necessary to carry out interdental cleaning on a regular basis, such as by using dental floss, interdental brushes, wooden sticks or powered interdental cleaning devices.
Interdental hygiene 3. Both waxed and unwaxed dental floss may be effective in narrow interdental spaces or the interproximal area, while dental tape, wooden sticks or interdental brushes have been shown to be more effective in wider interdental spaces. 4. Interdental cleaning with interdental brushes was shown to extend to 2. 5 mm below the gingival margin, while interdental floss may penetrate to a depth of up to 3. 5 mm.
Interdental hygiene 5. Approximately 85% of interdental surfaces exhibit plaque when oral hygiene is performed without interdental cleaning. 6. The absolute plaque levels in this area may be reduced by 30% to 40% after interdental cleaning, irrespective of the type of product used , in comparison to oral hygiene without interdental cleaning.
Fig 2. Mean range of penetration depths of toothbrushes and interdental hygiene devices
Supragingival irrigation 1. If applied supragingivally, the irrigant may penetrate up to 71% in shallow and up to 68% in moderately deep pockets. 2. However, with water or saline used as an irrigant, supragingival irrigation as a monotherapy was shown to be inferior to mechanical plaque control by conventional oral hygiene techniques, and its effect on supragingival plaque to be limited.
Supragingival irrigation 3. Also, the effect of supragingival irrigation on the subgingival microflora was reported to be negligible. 4. Thus, the overall antimicrobial effect of irrigation using tap water or saline on the oral microflora is limited.
Supragingival irrigation 5. Despite its poor efficacy in supragingival plaque control, irrigation was reported to lead to a marked reduction of gingival inflammation, such as bleeding on probing, possibly by diluting or washing away bacterial toxins.
Fig 3. Effectiveness of supragingival plaque removal using interdental hygiene devices
Professionally Performed Plaque Removal
Rubber cup and air powder polishing devices 1. Plaque and stain removal and to some degree also a polishing effect, are achieved by the mechanical action of the accelerated particles within a jet of water. 2. The efficacy of the instrument may be influenced by the powder and water setting, the distance of the jet from the treated surface and the shape and size of the particles used.
Rubber cup and air powder polishing devices 3. Supragingival plaque removal is considered to be more efficient with air powder polishing devices than with conventional rubber cup and polishing paste systems. 4. However, air powder polishing devices with conventional sodium bicarbonate powder may result in some clinically relevant loss of tooth substance, especially if applied to denuded root surfaces or dentin.
Hand instruments, sonic and ultrasonic scalers 1. All these instruments operate by pulling and pushing a sharp or cutting edge across the surface to be cleaned, thereby disrupting and dislodging the bacterial biofilm and calculus and removing stains. 2. The main plaque-removing effect of powder-driven scalers is, as in hand instrumentation, solely the mechanical action of the scaler tip.
Hand instruments, sonic and ultrasonic scalers 3. Antimicrobial effects are unlikely to result from disruption of bacterial cell walls, as in vitro studies have shown a clear lack of bactericidal effect on periodontopathogenic bacteria by ultrasonic and sonic scalers even after 150 seconds of exposure. Schenk et al. JCP 2000
Lasers 1. Their effectiveness and safety depend on the laser wavelength and the absorbing characteristics of the tissue to be treated. 2. The effectiveness of lasers in calculus removal is lower than that of ultrasonic scalers; also, higher surface roughness may occur after laser application. Aoki et al. JPR 2000
Lasers 3. Antimicrobial effects of lasers have been shown in vivo for diode (Lasers Surg Med 1998) and Nd: YAG lasers (Cobb et al. JP 1992; Liu et al. JP 1999) without any clinically relevant superiority of lasers over traditional debridement procedures being demonstrated.
Supragingival debridement 1. Professional supragingival debridement in conjunction with personal oral hygiene may result in plaque levels being reduced by adult half compared with baseline values. Bellini et al. JCP 1981; Katsanoulas et al. JCP 1992; Lavanchy et al. JCP 1987; Mc. Nabb et al. JCP 1992
Supragingival debridement 2. Lower plaque accumulations recorded in patients receiving frequent professional supragingival debridement may reflect a positive influence on oral hygiene compliance. Cugini et al. JCP 2000; Haffajee et al. JCP 1997; Harper JCP 1987; Hellstrom et al. JCP 1996; Kho et al. JCP 1985; Mueller et al. JCP 1986; Ximenez-Fyvie et al. JCP 2000
Supragingival debridement 3. Most studies examining the effects of supragingival plaque removal on the plaque in pockets deeper than approximately 3 mm find no significant alterations in the subgingival microbiota. Al-Yahfoufi et al. JCP 1995; Beltrami et al. JCP 1987; Dahlén et al. JCP 1992; Westfelt et al. JCP 1998
Supragingival debridement 4. In contrast, some authors claim that professional supragingival debridement has relevant effects on subgingival microbiota such as a lowering of total viable counts, increased proportions of gram (+) cocci and rods, and a decrease in periodontal pathogens such as A. actinomycetemcomitans, B. forsythus, P. gingivalis and T. denticola. Hellstrom et al. JCP 1996; Mc. Nabb et al. JCP 1992; Ximenez-Fyvie et al. JCP 2000
Supragingival debridement 5. Healing of the marginal gingiva with a concomitant reduction in probing depth may result from supragingival scaling, thus inducing changes in subgingival ecology. Kaldahl et al. JP 1996 6. It is supported by clinical studies that supragingival scaling alone is insufficient for the treatment of periodontitis. Kaldahl et al. JP 1996
Fig 4. Effectiveness of patient performed oral hygiene (OH) in comparison to adjunctive professional supragingival debridement (OH + Deb. )
Subgingival debridement and effectiveness 1. A critical review of studies evaluating the effectiveness of subgingival debridement procedures by a variety of assessment methods shows that a wide range of approximately 5% to 80% of treated roots have residual plaque or calculus deposits.
Subgingival debridement and effectiveness 2. Up to 30% of the total surface area of these roots may be covered with residual calculus following subgingival scaling. 3. Scaling efficacy is reduced with increasing pocket depth and furcation involvement. 4. The most important factors underlying improved scaling efficacy appear to be operator experience, skill and training.
Fig 5. Diagram showing the reduction and recolonization pattern in subgingival debridement
Bacterial regrowth and recolonization 1. Bacterial regrowth and recolonization of the pocket occur, with subgingival bacterial counts being restored almost to pretreatment values 3 to 7 days after treatment. Harper et al. JCP 1987 2. However, the change induced in the composition of the microflora lasts longer.
Bacterial regrowth and recolonization 3. A significant decrease in mean counts, site specific prevalence and proportions following therapy was found for B. forsythus, P. gingivalis and T. denticola. 4. In contrast, a significant increase occurs in the mean proportion of Actinomyces spp. Veillonella parvula, Capnocytophaga spp. and non-periodontopathogenic streptococci, with the dynamics of subgingival recolonization appearing to play a major role in this context.
Bacterial regrowth and recolonization 5. Following the removal of the bacterial biofilm, parts of the early colonizers, which are predominantly nonpathogenic, may be faster in occupying the “vacant” habitat, and thus inhibit the establishment of pathogens. 6. This means that, in clinically successful treatment, subgingival scaling and root planing will lead to reduced counts of periodontal pathogens.
Bacterial regrowth and recolonization 7. To prevent rebound to pretreatment levels of periodontal pathogens in subgingival plaque, repeated reinstrumentation and mechanical removal of subgingival plaque ie essential. 8. This underlines the importance of regularly performed supportive periodontal therapy including subgingival debridement of pockets deeper than 3 to 4 mm.
Immune response induced by subgingival debridement 1. The inoculation of periodontal pathogens during debridement and the resulting bacteremia may also cause systemic effects. 2. As a result of the increased exposure of the immune system to periodontal pathogens following scaling, seroconversion in patients previously seronegative to periodontal pathogens or a significant increase in antibody titers in patients seropositive before therapy has been shown to occur.
Immune response induced by subgingival debridement 3. For example, an increase in serum antibody titers against A. actinomycetemcomitans and P. gingivalis was found after scaling. Ebersole et al. Infect. Immun. 1985 4. Thus, mechanical therapy may induce a humoral immune response, and this may be one of the reasons for clinical improvement after therapy. Sjöström et al. Infect. Immun. 1994.
Immune response induced by subgingival debridement 5. However, the influence of subgingival debridement on patients diagnosed as seropositive for different periodontal pathogens before treatment is not yet fully understood and data are equivocal. 6. Besides an increase in antibody titers, slightly decreased or unchanged serum antibody titers against specific periodontal pathogens following treatment have also been reported.
Periodontal flap surgery 1. As thoroughness of debridement has been shown to decrease with increasing pocket depth and inaccessibility, periodontal flap surgery is often considered a valuable adjunct to subgingival debridement in deep pockets. Jones & O’Leary JP 1978; Lövdal et al. Acta Odontol. Scand. 1961; Rabbani JP 1981; Waerhaug JCP 1975, JP 1978
Periodontal flap surgery 2. The need for surgery is reduced with increasing levels of operator experience and skill. 3. The influence of operator skill is, however, limited in multirooted teeth, as furcation anatomy has been found to have a substantial impact on debridement ability. Bower JP 1979
Periodontal flap surgery 4. Overall, the attainable percentages of calculus-free surfaces after both nonsurgical and surgical techniques appear to be much lower in molars compared with single rooted teeth, especially for pockets exceeding 6 mm probing depth. Fleischer et al. JP 1989; Parashis et al. JCP 1993 a, b
Pocket depth and treatment efficacy 1. In single-rooted teeth with pockets exceeding 4 mm of pocket depth, it has been documented that well-trained operators achieve a greater percentage of calculus-free root surfaces with both nonsurgical or surgical techniques compared with untrained operators. Brayer et al. JP 1989
Pocket depth and treatment efficacy 2. In pockets exceeding 6 mm, the amount of undebrided root surfaces left behind after closed scaling by experienced operators were even similar to those left by less experienced operators using the open debridement technique. Brayer et al. JP 1989
Periodontal surgery and subgingival microflora 1. No significant differences in mean counts and sitespecific prevalence rates of various periodontal pathogens were observed between subgingival scaling and access flap surgery. Pedrazzoli et al. JCP 1991; Renvert et al. JCP 1990
Periodontal surgery and subgingival microflora 2. Compared with pretreatment levels, modified Widman surgery failed to induce profound microbiological changes and to readicate A. actinomycetemcomitans, P. gingivalis, Prevotella intermedia and B. forsythus (Haffajee et al. JCP 1995), and recolonization of the subgingival environment occurred after a 2 - to 4 -week period (Mayfield et al. JCP 1998).
Periodontal surgery and subgingival microflora 3. Overall, the shift in the composition of the subgingival microflora following access surgery is similar to what is found following subgingival debridement. Haffajee JCP 1995, JCP 1997
Residual pocket depth and microbiota 1. The physicochemical characteristics of the physiological sulcus differ substantially from those found in deep pockets. 2. The oxygen partial pressure and the redox potential in shallow and deep periodontal sites differ significantly. Kenney JP 1969; Mettraux et al. JP 1984
Residual pocket depth and microbiota 3. Therefore, anaerobic conditions are more likely to occur in deep pockets, which in turn may favor colonization with suspected periodontal pathogens. 4. As a consequence, one aim of surgical interventions may be to alter the subgingival environment by reducing pocket depths.
Residual pocket depth and microbiota 5. For example, after converting deep pockets into shallow sites by means of apically positioned flap surgery and osseous recontouring without deliberate root debridement, significant decreases in the proportion of gram (-) anaerobic rods were observed. Mombelli et al. JCP 1995
Residual pocket depth and microbiota 6. The clinical and microbiological outcomes were similar to those achieved by concomitant scaling and root planing during surgery, so that these microbiological changes may be attributed primarily to morphological alterations of the subgingival ecological niche.
Residual pocket depth and microbiota 7. Other studies detecting reduced counts and decreased proportions of pathogens in the subgingival microflora after resective periodontal surgery confirm the relevant role of pocket elimination techniques in periodontal therapy. Levy et al. IJPRD 1999; Nowzari et al. JP 1996
Fig 6 Palatal aspect of upper left quadrant before (left) and after (right) resective flap procedure with osseous recontouring. Arrows indicate previous subgingival root surfaces.
Summary and conclusion 1. Self-performed plaque removal using manual or powered toothbrushes and interdental cleaning devices is improved in subjects that have received oral hygiene instructions. 2. Personal oral hygiene coupled with regular professional supragingival debridement may further improve the level of plaque control but still fails to achieve a completely plaque-free dentition.
Summary and conclusion 3. Both patient-performed and professional supragingival plaque removal has an effect on subgingival microbiota that is limited to the marginal 3 mm of the periodontal pocket. 4. At sites with 4 mm or more of probing depth, only subgingival scaling leads to a significant reduction of the bacterial load.
Summary and conclusion 5. The subgingival microflora can be further reduced by pocket elimination surgery. 6. Due to the sequence of bacterial recolonization that occurs following mechanical debridement, the level of periodontal pathogens such as B. forsythus, P. gingivalis and T. denticola may be reduced for several months.
Summary and conclusion 7. Mechanical debridement also influences the patient’s immune system response, resulting in antibody titers and avidity against periodontal pathogens. 8. As a basis for the restoration and maintenance of periodontal health repeated subgingival debridement, as performed in supportive periodontal therapy, can reduce the number and proportions of periodontopathogenic bacteria in subgingival plaque.
Summary and conclusion 9. However, intensive subgingival scaling and root planing should be avoided in sites that probe less than 3 mm, as this is likely to traumatize the periodontium and cause attachment loss.
- Slides: 57