Efficacy of scaling and root planing

Numerous investigations support the efficacy of scaling and root planing in the treatment of periodontal disease. Typically studies show that posttreatment pocket depth reduction is directly related to the initial pocket depth, with the greatest reduction noted for the deepest pockets. A consistent relationship is also found between changes in the attachment levels and initial pocket depth. In a thorough review of the literature, the mean probing pocket reduction and mean attachment gain following scaling and root planing were determined for shallow, deep, and moderately deep sites. Shallow pockets (1–4 mm) and moderately deep sites (4–7 mm) had a mean pocket reduction of 0.03 mm and 1.29 mm, respectively, whereas deep sites (>6 mm) showed the greatest pocket depth reduction of 2.16 mm. The mean attachment gain for shallow, moderately deep, and deep sites was –0.34 mm, 0.55 mm, and 1.19 mm, respectively. This study also showed a mean reduction in bleeding on probing of 57% post-therapy.

Thus, the data highlight the magnitude of the effects of nonsurgical mechanical therapy on periodontal clinical indices and also demonstrate that attachment loss is to be expected when shallow periodontal pockets are scaled and root planed.

Efficacy of periodontal surgery

Most of the longitudinal studies demonstrate that scaling and root planing and surgical approaches are similarly effective. Meta-analyses by Antczak-Bouckoms and colleagues, Berkley and colleagues, and Heitz-Mayfield and colleagues evaluated reduction in probing pocket depth (PPD) and gain in clinical attachment levels as primary outcome measures. The reviews are highly consistent in that scaling and root planing alone and scaling and root planing combined with flap procedure are accepted as effective methods for the treatment of chronic periodontitis in attachment level gain and gingival inflammation reduction.

Heitz-Mayfield and co-workers concluded that sites with initial PPD of 1 to 3 mm treated with open flap debridement resulted in significantly greater loss in clinical attachment levels compared with scaling and root planing. When sites with initial PPD of 4 to 6 mm were treated with open flap debridement, there was significantly less clinical attachment level (CAL) gain compared with scaling and root planing. The PPD reduction was significantly greater following the open flap debridement procedure. Finally, when sites with initial PPD greater than 6 mm were treated with surgical procedures, there was significantly more CAL gain than with the standard procedures of scaling and root planing. Open flap debridement resulted in significantly more PPD reduction than did the nonsurgical scaling and root planing approach in these deep pockets.

Lindhe and colleagues demonstrated that in a well-controlled oral hygiene regime, thorough scaling and root planing was equally effective when used alone or in combination with the modified Widman procedure in the treatment of advanced periodontitis. A high frequency of probing depths less than 4 mm was noted following both treatment modalities, and the investigators speculated that the attachment gain after treatment reflected a reduction in the degree of gingival inflammation rather than a true gain of connective tissue attachment. The clinical improvements after mechanical debridement remained unchanged during an 18-month maintenance period. During this period, recurrence occurred, but it was a rare finding and when it did develop it was related to either ineffective prophylactic measures or inadequate debridement during active treatment.

Efficacy of periodontal surgery

Most of the longitudinal studies demonstrate that scaling and root planing and surgical approaches are similarly effective. Meta-analyses by Antczak-Bouckoms and colleagues, Berkley and colleagues, and Heitz-Mayfield and colleagues evaluated reduction in probing pocket depth (PPD) and gain in clinical attachment levels as primary outcome measures. The reviews are highly consistent in that scaling and root planing alone and scaling and root planing combined with flap procedure are accepted as effective methods for the treatment of chronic periodontitis in attachment level gain and gingival inflammation reduction.

Heitz-Mayfield and co-workers concluded that sites with initial PPD of 1 to 3 mm treated with open flap debridement resulted in significantly greater loss in clinical attachment levels compared with scaling and root planing. When sites with initial PPD of 4 to 6 mm were treated with open flap debridement, there was significantly less clinical attachment level (CAL) gain compared with scaling and root planing. The PPD reduction was significantly greater following the open flap debridement procedure. Finally, when sites with initial PPD greater than 6 mm were treated with surgical procedures, there was significantly more CAL gain than with the standard procedures of scaling and root planing. Open flap debridement resulted in significantly more PPD reduction than did the nonsurgical scaling and root planing approach in these deep pockets.

Lindhe and colleagues demonstrated that in a well-controlled oral hygiene regime, thorough scaling and root planing was equally effective when used alone or in combination with the modified Widman procedure in the treatment of advanced periodontitis. A high frequency of probing depths less than 4 mm was noted following both treatment modalities, and the investigators speculated that the attachment gain after treatment reflected a reduction in the degree of gingival inflammation rather than a true gain of connective tissue attachment. The clinical improvements after mechanical debridement remained unchanged during an 18-month maintenance period. During this period, recurrence occurred, but it was a rare finding and when it did develop it was related to either ineffective prophylactic measures or inadequate debridement during active treatment.

Advances in nonsurgical treatment protocols

Quirynen and colleagues introduced the one-stage full-mouth disinfection, including adjunctive use of chlorhexidine (mouth rinsing and disinfection of all intraoral niches), and they compared the clinical and microbiological effects of this treatment strategy with the more traditional treatment of quadrant scaling and root planing at 2-weekly intervals with no adjunctive use of chlorhexidine. The one-stage protocol included full-mouth scaling and root planing under local anesthesia using hand and ultrasonic instruments, completed over 2 sessions within 24 hours. Time spent for treating one quadrant was approximately 1 hour. The disinfection of the oral cavity also involved an extensive application of chlorhexidine to all intraoral niches, such as periodontal pockets, tongue dorsum, tonsils, and oral mucous membranes, chairside and at home, for 2 months. The rationale behind the full-mouth disinfection was to prevent reinfection of the instrumented sites from the remaining untreated pockets and from other intraoral niches.

Thereafter, the Leuven research group conducted a series of clinical trials and consistently demonstrated a superior clinical outcome for the one-stage full-mouth disinfection treatment modality. This treatment strategy evolved such that the clinical protocol of the full-mouth scaling and root planing was completed in 24 hours or less, with no adjunctive use of antiseptic agents. However, these reported gains in clinical and microbiological indices achieved for the full-mouth approach by the Leuven group have not been found by subsequent researchers, which has generated an ongoing debate as to whether the full-mouth clinical protocol should be the treatment of choice.

Data from other studies provide concurrence that chlorhexidine does not augment the beneficial outcome of periodontal therapy, and when this does occur, it is a transient phenomenon rather than a long-term effect. However, it should be stressed that in the quoted studies, chlorhexidine was used as a single measure of disinfection in contrast to the treatment protocol of multiple chlorhexidine applications used in the Leuven studies. Nevertheless, there is a general agreement in the literature that clinical trials with a lack of meticulous plaque control gave misleadingly promising results for the adjunctive use of chlorhexidine.

A later study by the Leuven research group examined patients with moderately advanced periodontitis and concluded that the benefits of the full-mouth treatment protocol were partially due to the antiseptics and partially, the shorter time for completion of the therapy; this conclusion contradicts earlier findings that questioned the role of the antiseptics in this treatment strategy. The earlier study demonstrated that the full-mouth treatment with chlorhexidine was superior to all other treatment strategies in patients with advanced periodontitis. Although the full-mouth group showed greater improvements in pocket depths and attachment levels compared with the quadrantwise treated group, with antiseptics used in neither group, this failed to reach statistical significance at 8 months ( P ≤.10). The group that received the quadrantwise treatment in this study scored considerably better in pocket depth reductions than in the earlier study, and this discrepancy may explain the differences in the 2 studies from the same research group.

Apatzidou and Kinane randomized 40 patients into 2 treatment groups (one-day full-mouth root planing versus quadrantwise root planing) and followed these subjects over 6 months. Although the one-day group was mechanically treated on the same day, they were still seen every second week to receive the same amount of oral hygiene instruction and motivation as the quadrantwise group. This resulted in similar plaque indices between the treatment groups throughout the study; this result disagrees with the findings of Vandekerckhove and colleagues, who showed higher plaque indices for the one-stage full-mouth disinfection group after the first month, possibly due to lack of frequent sessions of oral hygiene reinforcement. Periodontitis is a chronic multifactorial inflammatory disease process, which requires the commitment of the patient and the therapist in achieving long-term periodontal stability. Although the full-mouth treatment is completed within hours, patients with periodontitis, especially advanced cases, should be monitored closely and frequently by the therapist until the time of the initial reassessment to optimize the oral hygiene, establish a relationship between patient and therapist, and consolidate the long-term commitment. Considering this argument and in contrast to the conclusions of the Leuven group, full-mouth scaling and root planing, which requires approximately 1 hour of instrumentation per quadrant completed in 1 day or on 2 consecutive days, offers no additional economic advantages over the classic quadrantwise treatment. On the other hand, recent studies point out that single-visit, full-mouth or quadrantwise ultrasonic debridement with or without the adjunctive use of antiseptics is less laborious and time-consuming, yet equally efficacious clinically as the standard periodontal therapy of scaling and root planing. Koshy and colleagues reanalyzed the effects of full-mouth and quadrantwise treatment by using ultrasonics rather than hand instrumentation. Their protocol, briefly stated, was to complete full-mouth ultrasonic debridement in 2.5 hours or less with either povidone-iodine or water as irrigant for the ultrasonic device and to compare the clinical outcome and polymerase chain reaction findings of this treatment with the quadrantwise ultrasonic debridement. Their results demonstrated that the single-visit debridement had limited additional benefits over the partial treatment, except that, from a practical perspective, less time was required overall to complete treatment in one visit than over 4 consecutive sessions.

Wennström and co-workers reduced the time frame of periodontal therapy of patients with moderately advanced chronic periodontitis to 1 hour with the use of ultrasonics solely under local anesthesia, if requested by the patient. The reported data demonstrated that the 1-hour treatment resulted in a smaller percentage of “closed” pockets (PPD <5 mm) compared with the classical treatment of quadrant-by-quadrant scaling and root planing with hand instruments on a weekly basis, but it also demonstrated that the efficiency of the initial treatment phase (baseline to 2 months), defined as the time spent for instrumentation divided by the number of closed pockets, was significantly higher for the full-mouth ultrasonic debridement. In this study, oral hygiene instructions were given on 3 occasions in a similar manner for both treatment groups. The investigators highlighted the practical benefits of this treatment approach over the quadrantwise or full-mouth treatment of scaling and root planing, which is either performed over 2 sessions within 24 hours or over 4 sessions at biweekly intervals. Their results suggest that the 1-hour debridement may be a justifiable initial treatment approach for the patient with chronic periodontitis, and they emphasize that fewer appointments and less chair time are required for this treatment that has less postoperative discomfort compared with the traditional approach of quadrant scaling and root planing.

Rationale for ultrasonic debridement

There has been extensive discussion on whether power-driven devices/ultrasonics are as effective as hand instruments in debriding the root surface. Randomized controlled clinical trials confirmed by other studies showed no significant differences between power-driven and hand instrumentation in nonsurgical periodontal treatment. The systematic review by Walmsley and colleagues essentially reiterates that power-driven and conventional hand instrumentation techniques are equally efficacious, and despite extensive research and refinement in the power-driven field, showing substantial clinical improvements with these new methodologies is still some way off. Promising future developments in tip designs and in the generators used to develop power may provide clinical superiority; however, clinical verification of the utility of these advances is still needed. Advantages associated with power-driven instruments include better access to deep lesions by way of well-designed long tips, and similarly improved tips may provide advantages in furcation areas. Some studies suggest less postoperative discomfort and less cementum removal with ultrasonics, but these findings are not universally demonstrated and devices in common use outside rigid study protocols are typically used suboptimally. Clearly, more research is needed in this area.

Although mechanical therapy, hand instrumentation or ultrasonic debridement, is the most common therapy for periodontitis of varying severity and has well-documented efficacy, there is a price to pay for this successful therapy, that is, the considerable amount of time and cost involved, the high level of operator skill needed, and some unavoidable discomfort for the patient. Based on these considerations, the short treatment regimes, which include full-mouth ultrasonic debridement that is completed within a few hours, may constitute a significant paradigm shift in periodontal practice.

Initially, the objective of scaling and root planing was to remove soft and hard deposits, such as microbial biofilm and calculus, from the periodontal pocket and considerable amounts of infected cementum or even dentin from the root surface. The rationale behind this treatment was to eliminate bacterial endotoxins penetrating into the cementum and thus establish local conditions ideal for soft-tissue healing. However, recent data point out that endotoxins do not penetrate into the cementum, but on the contrary, they loosely adhere to the surface of the root cementum. Although, the necessity for removal of root substance is questioned, a fairly smooth root surface does not retain microbial plaque and is thus a useful goal following instrumentation, but intentional and focused removal of root cementum is not necessary. On this basis, the use of instruments that disrupt the biofilm and remove deposits from a periodontal pocket, while causing minimal mechanical trauma to the structure of the root, is considered highly advantageous and ultrasonic devices are effective to this end.

There are no categorical reports that newer designs of powered instruments are more advantageous than the conventional ultrasonic devices or that slimmer tip designs improve clinical outcomes compared with the traditional inserts. Despite slimmer tip designs having better access to the narrow and deep periodontal pocket and minimizing soft tissue trauma during debridement, in vitro studies suggest that mechanical inefficiencies result from variations in the load applied to the tip and the flow rate of the irrigant. Walmsley and co-workers (in 2008) reported that there is a need for manufacturers to use quality control programs and undertake clinical assessment studies before promoting these new technologies. Such studies would help instruct clinicians in their use and selection of power driven designs.

Host response changes following periodontal therapy

Many studies have sought to determine the changes in antibody titers to putative periodontal pathogens following treatment. These changes can provide criteria on which to evaluate periodontal treatment and prognosis. Quirynen and colleagues observed that 7 out of 11 patients, whose body temperature rose to more than 37°C after the second day of the one-stage full-mouth scaling and root planing, with or without the use of chlorhexidine treatment, had an overall pocket depth reduction exceeding 3.5 mm, whereas this was noted for only 4 of the remaining 13 patients that did not have an increase in temperature. Patients with an increase in body temperature on the evening after the second day of the full-mouth treatment had the more impressive clinical improvements, which was considered by the investigators to be due to an increased immunologic reaction. The investigators speculated that this might be the beneficial aspect of this treatment strategy.

One study investigated this hypothesis and frequent blood samples were taken from patients (biweekly intervals) over a longer period (overall 6 months) than had previously been done. The data showed that although full-mouth instrumentation was completed in a shorter period (12 rather than 24 hours), no significant differences in the IgG antibody titers against 5 putative periodontal pathogens were detected compared with the standard quadrant root planing at biweekly intervals over a period of 6 months. Fortnightly sessions of quadrant root planing probably result in a similar host immune response to 12- or 24-hour full-mouth treatment, even though the latter treatment approach would be expected to have a greater potential for repeated inoculation of bacteria into the host tissues, thus eliciting a stronger immune response. Although IgG antibody titers were similar for both treatment groups, a significantly greater reduction in the antibody levels for Prevotella intermedia and Treponema denticola was seen between baseline and the initial reassessment (6 weeks after the completion of the instrumentation) for the full-mouth treated group compared with the quadrant group. When the changes in the serum antibody response over the course of treatment were considered within each treatment group, significant reductions in the IgG antibody levels for P intermedia and T denticola were seen between baseline and the initial reassessment for the full-mouth group, but this was not found for the quadrantwise group. These findings imply that same-day full-mouth treatment seems to have a stronger short-term effect on the systemic antibody response compared with the classical therapy of quadrant root planing at biweekly intervals, which complies with later data by Wang and colleagues. However, the clinical significance of this finding is difficult to assess. The authors experience is that short-term perturbations of antibody responses occur during the active phase of periodontal therapy, but they show great variation across subjects and are therefore, difficult to meaningfully interpret.