Treatment of periodontitis follows an incremental step approach in which the first step
is aimed at modifying patient behavior with the goal of supragingival plaque reduction.
The second step is subgingival instrumentation, performed with different instruments and
treatment timing and with or without additional therapies. However, in periodontitis
patients, the complete removal of subgingival biofilm and calculus at teeth with deep
probing depths (≥6 mm) or complex anatomical surfaces (root concavities, furcations,
infra bony pockets) may be difficult, and hence, the endpoints of therapy may not be
achieved, and further treatment should be implemented.
The third step of therapy is aimed at treating those areas of the dentition
non-responding adequately to the second step of therapy (presence of pockets ≥4 mm with
bleeding on probing or presence of deep periodontal pockets [≥5 mm]), with the purpose of
gaining further access to subgingival instrumentation, or aiming at regenerating or
resecting those lesions that add complexity in the management of periodontitis
(intra-bony and furcation lesions).
Periodontal reevaluation is performed after step 2. The case reevaluation, executed after
the completion of the first step of periodontal therapy, allows to assess the response to
therapy, to specify the prognosis of the case and the possible need for further treatment
and, consequently, to finalize and correct the case's periodontal treatment plan.
Many different time intervals, ranging from 2 weeks to 6 months, have been documented in
periodontal literature to be the best time to perform reevaluation.
The decision on the timing of reevaluation is secondary to the expression of the clinical
benefits of the first two steps of therapy. Classic studies show that the most
significant changes occur during the first 3 months after instrumentation, with little
change during the next 12 months.
Cugini studied the microbiological and clinical effect of subgingival instrumentation and
found that most of the clinical improvements and microbial changes occurred during the
first 3 months after SRP. In particular, the mean attachment level decreased
significantly at 3 months and was maintained during the 12 months of the study. Other
clinical parameters, such as mean pocket depth and the percentage of sites that bled on
probing, showed marked improvement at 3 months after SRP, but also during the maintenance
period.
Another study, in which 40 patients were randomized to Q-SRP or FMI showed that both
therapies resulted in significant improvements in all clinical indices both at 6 weeks
and 6 months. A continuous clinical improvement was seen for both treatment groups during
the experimental period, which reached peak levels at 6 months.
A further study, that again compared two different approaches for sub-gingival
instrumentation showed that the initial treatment phase resulted in ''pocket closure'' at
a mean frequency of 58% for the FMD and 66% for the Q-SRP approach. Following
re-treatment of the remaining pockets, the mean percentage of closed pockets increased to
74% for FMD and to 77% for Q-SRP.
A recent systematic review showed that, despite no differences exist on the mode of
delivery of non-surgical therapy, at shallow sites (4-6 mm), a mean reduction of PD of
1.5 mm can be expected at 6/8 months, while at deeper sites (≥7 mm) the mean PD reduction
was estimated at 2.6 mm. In addition, based on the results of 9 studies, the authors
concluded that the proportion of closed pockets was estimated to be 57% and 74% at 3 and
at 6 months, respectively.
Taking into account the overall patient, it becomes clear that the possibility of having
an optimal effect (i.e. pocket closure) on a single site or a single tooth might have a
minimum or a non-significant clinical effect on the overall treatment plan of a patient.
The aim of this study is to compare two different timing of re-evaluation, in terms of
clinical indexes (PPD reduction; Pocket closure) and patients' morbidity (number of
further therapies needed).
Materials & Methods
This trial will be a single-blinded, randomized controlled clinical trial with a 6 months
follow-up.
Following a screening examination including full-mouth probing and a radiographic
evaluation, 40 patients will be recruited from the Department of Periodontology (AOU
Careggi, Firenze).
Inclusion criteria:
Adults with a diagnosis of Generalized, stage III or stage IV periodontitis; At least 20
teeth present At least eight teeth must show probing pocket depths (PPD) of ≥5mm and
bleeding on probing (BOP). At least two of these teeth must have a PPD of ≥7 mm and at
additional two teeth, the pockets must measure ≥6 mm;
Exclusion criteria:
Patients receiving periodontal treatment in the past 12 months; Patients receiving
antibiotics in the past 3 months; Known medical conditions that affects the progression
of periodontitis or that affect the outcomes of periodontal therapy; Compromised medical
conditions requiring prophylactic antibiotic coverage; and ongoing drug therapy that
might affect the clinical signs and symptoms of periodontitis.
One examiner (an experienced periodontist, L. Barbato), who will be masked with respect
to the treatment assignments, will retrieve all clinical recordings.
Full mouth clinical examination will be performed at baseline including clinical photos,
full-mouth radiographs, along with a complete medical and dental history.
The enrolled subjects will be stratified according to smoking habits and randomly
allocated to two different arms: (1) Subgingival instrumentation and re-evaluation at 3
months or (2) Subgingival instrumentation and re-evaluation at 6 months. To optimize the
study design, step 1 periodontal therapy will be performed at the same time as step 2. To
overcome possible bias due to different delivery timing of subgingival instrumentation,
therapy will be delivered as a full mouth instrumentation or in two sessions one week
apart. Therapy will be derived by post-graduate students with significant clinical
experience in non-surgical therapy (post-graduate year 2 or 3). After baseline recordings
and a detailed case presentation to the patient, the therapy will be delivered. The
patients will be recalled monthly for re-enforcement of motivation and oral hygiene
instruction and supra-gingival plaque removal. In the context of this appointments, no
sub gingival re-instrumentation will be performed. At 3 months (group 1) and at 6 months
(group 2) the same examiner will retrieve the re-evaluation periodontal chart.
According to recently published clinical guidelines for the treatment of stage III/IV of
periodontitis, one of the authors (a periodontist with more than 10 years of experience,
Cairo) will compile, for every clinical case, a complete corrective treatment plan, which
may include non-surgical re-treatment, surgical conservative therapy, osseous resective
therapy or regenerative therapy.
The definitive treatment plan will be drawn up and described for all those elements that
have not achieved, after step 1 and 2 periodontal therapy, the therapeutic endpoints (no
PPD≥5 mm and no PPD=4 mm with BOP).
Patient mean values will be calculated for the statistical analysis. The primary variable
will be the number of teeth needing further therapies. Secondary variables will be PPD
reduction, Pocket closure (i.e. no PPD≥5 mm and no PPD=4 mm with BOP), number of
surgeries performed and also PROMs will be evaluated. A cost analysis will be performed.