Evaluation of Endodontic Status on Periodontal Healing of Concomitant Endodontic Periodontal Lesions
Condition: Periodontal Pocket
MeSH terms: Periodontal Pocket
Study type: Interventional

Summary: 
      Introduction:

      To evaluate the effect of untreated endodontic infection on periodontal status in untreated
      non vital teeth with periapical radiolucency as compared to contralateral vital teeth. And
      also to evaluate the role of endodontic treatment on periodontal healing in successfully
      endodontically treated teeth with contralateral vital teeth.

      Methods:

      This study was performed in two parts. First part of this study was an observational cross
      sectional survey and second part was a clinical trial on patients selected from the survey.
    

Detailed description: 
      Title: EVALUATION OF ENDODONTIC STATUS ON PERIODONTAL HEALING OF CONCOMITANT ENDODONTIC
      PERIODONTAL LESIONS

      INTRODUCTION:

      Although deleterious effects of endodontic tissue on the periodontium are well documented,
      the converse effect of periodontal disease on pulp remains unclear. There is abundance of
      research on the avenues of communication but still many doubts exist. High prevalence of
      accessory canals has been seen but not all primary endodontic lesions drain through the
      periodontal ligament. Many endodontic lesions are more prone to drain through cortical bone
      rather than through the periodontal ligament. It may be because of the nature of
      periradicular lesions which initially try to expand horizontally through cancellous bone and
      then progressing vertically. Evidence also suggests that endodontically treated teeth lack
      the same proprioceptive capability as endodontically untreated teeth so they may be subjected
      to greater occlusal forces. More forces could enhance the propagation of fracture lines along
      the root surface, resulting in more periodontal attachment loss. Also teeth associated with
      either root perforations or fractures appear to follow periodontal drainage routes whereas
      lesions of primarily pulpal origin seem to remain localized or drain through cortical bone.
      Many explanations are provided, firstly periodontal ligament may be resistant to bacterial
      insult of endodontic origin, or injuries originating through mechanical trauma are faintly
      recognized, causing a subtle attachment loss occurring secondary to routine endodontic
      disease. Another explanation could be that the main or accessory canals might not be the solo
      and most important route of communication and endodontic infection might also proceed along
      cervically located dentinal tubules.

      A group of retrospective and experimental studies in the past demonstrated the effect of
      endodontic infection on periodontal status and healing. A series of retrospective studies
      performed on single rooted teeth of periodontitis prone patients correlated endodontic
      infection with periodontal status in terms of pocket depth and attachment loss. Teeth with
      periapical radiolucency demonstrated deeper pockets and more radio graphic attachment loss as
      compared to a healthy tooth. Non surgical periodontal treatment with horizontal defects
      depicted reduced mean pocket depth reduction and increased radio graphic attachment loss in
      teeth with periapical pathology in comparison with endodontically intact tooth. Even multi
      rooted teeth with periapical destruction in periodontitis prone patients exhibited
      significantly greater mean probing depth compared to teeth without periapical destruction.
      Mandibular molars with periapical destruction showed ≥ 3 mm horizontal furcation depth. In
      all these studies periodontal parameters of teeth (either root filled or with a periapical
      radiolucency) were compared with an endodontically intact tooth also present in the patients
      without any consideration of quality of obturation.

      Research has denoted that endodontic treatment influences the periodontal healing and
      periodontal status of tooth.

      Reduced healing potential of the periodontal structures by endodontic treatment was evident
      in human studies.

      Endodontic infection is a local modifying risk factor is based on retrospective studies
      experimental studies. Prospective studies have been carried out to evaluate effect of
      endodontic treatment on periodontal healing only. The present understanding on the effect of
      endodontic status on periodontal status and healing is mainly based on retrospective studies
      where numbers of variables evaluated are limited with a low level of reliability. They lack
      the power to accept or reject any hypothesis. The retrospective studies had no control on
      quality of obturation and lacked standardization of radiographs. Moreover the experimental
      studies were conducted in extreme conditions and lacked similarity to clinical conditions. No
      prospective study has yet compared the periodontal status as well as periodontal healing in
      untreated non vital teeth and successfully endodontically treated teeth with contralateral
      vital teeth.

      So, the purpose of this study was to evaluate the effect of untreated endodontic infection on
      periodontal status in untreated non vital teeth with periapical radiolucency as compared to
      contralateral vital teeth. And also to evaluate the role of endodontic treatment on
      periodontal healing in successfully endodontically treated teeth with contralateral vital
      teeth.

      Methods:

      All patients with the diagnosis of generalized chronic periodontitis were screened for a non
      vital tooth with periapical radiolucency that also had contralateral vital tooth with normal
      periapical conditions in the radio graph. A split mouth design was followed with non vital
      tooth with periapical radiolucency (test group 1) and a contralateral vital tooth (test
      group2) present in each patient.

      Parameters recorded:

        1. Site specific clinical parameters like probing depth, clinical attachment loss, bleeding
           on probing, plaque score.

        2. Digital radio graphic evaluation was done by taking intra oral periapical radiographs.
           Bone level and periapical score was recorded.

      Follow up of patients was done at 1, 3 and 6 months to evaluate the improvement in
      periodontal parameters and PAI score.

      Endodontic treatment protocol: Using a standardized protocol root canal treatment was
      performed by a single operator for all cases. Initially local anesthesia was provided (2%
      Novocaine with 1:80,000 epinephrine), isolation was achieved by rubber dam and standard
      access cavity preparation was done.

      Using 3 % sodium hypochlorite, canal negotiation was done & apical patency was achieved with
      #10 or #15K-files. Coronal flaring was created with # 2 and #3 Gates-Glidden drills (Dentsply
      Maillefer, Tulsa, OK). With the help of a Root-ZX apex locator working length of each canal
      was established (J Morita, Irwine, CA) and then verified with radiographs.

      A crown down technique for canal instrumentation was followed using hand K files. The master
      apical file size was set at 3 sizes larger than the first binding file at working length.
      Instrumentation was accompanied with copious irrigation of 3% sodium hypochlorite using 27
      gauge needles. Calcium hydroxide was filled in the canals with the help of a lentulo spiral
      and patients were scheduled for a second appointment to complete root canal therapy within 10
      days to obturate the canal. At the second appointment, after removing the calcium hydroxide
      paste circumferential filing with Hedstrom-type files was done and copious irrigation with 3%
      sodium hypochlorite was followed by 5.0 ml 17% ethylenediaminetetraacetic acid with a final
      rinse of 5.0 ml of 3% sodium hypochlorite.

      The canals were dried with sterile paper points and obturated by using lateral condensation
      technique with gutta-percha (Dentsply Tulsa Dental) and ZOE sealer.

      Periodontal treatment protocol - Non surgical periodontal treatment in the form of scaling
      and root planing was provided in minimum of two sessions using ultrasonic scaler (Satelec P5
      Booster Suprasson) and hand instruments (Hu-friedy scalers and curettes). In the first
      session supragingival scaling was done and in the second session root planing was performed
      until a clinically hard, smooth surface was achieved.

      Sample size:

      Assuming the effect size of 0.5, power .95 and α=0.05 a sample of 105 patients in each group
      was required for the survey to show clinically significant difference. For the clinical trial
      with the effect size of 1, power .80 and α=0.05, 17 patients in each group were required to
      elicit a clinical significant difference. To further compensate for the drop outs, 28
      patients in each group were enrolled for the study.

      Statistical Analyses:

      Shapiro-Wilk normality test showed that data for the survey and for the clinical trial was
      non normally distributed. The differences between the groups in survey and the clinical trial
      for continuous variables were assessed using Mann-Whitney U test and for categorical
      variables (brushing habits and dexterity) using chi square (χ2) test.

      Partial correlation between variables in the survey was assessed after controlling the
      potential confounders like age and PI. Multiple linear regression analysis was used to
      develop models of predictor variables (PAI, tooth, gender) associating to the dependent
      variables (mean probing depth (PD), maximum probing depth (PD max), mean attachment loss
      (AL), maximum attachment loss (AL max), mean bone level. Scoring of pocket depth, attachment
      loss and PAI was further categorized as 0 (PD<4mm, AL<4mm and PAI=absence of radiolucency)
      and 1 (≥4 to ≤8 PD, AL and PAI=presence of radiolucency). Similarly scoring of mean bone
      level was categorized as 0 (<5mm) and 1 (≥5mm) for purpose of logistic regression. The
      evaluation of the association between PD, AL and PAI was estimated by odds ratio (OR) and 95%
      confidence intervals (95% CI).

      Evaluation of improvement in clinical parameters (PD, PD max, AL, AL max, BOP, PI, PAI) in
      the two test groups (Test group1 and Test group 2) was done using intra group comparison at
      baseline to 1month, baseline to 3 months, baseline to 6 months,1 to 3 months, and 3-6 months
      using the Wilcoxon signed rank test. The differences in improvement of clinical parameters
      between the two test groups ((Test group1 and Test group 2) was assessed using Mann-Whitney-U
      analysis. Statistical signiﬁcance was set at the 95% probability level (P < .05).
    

Intervention name(s): Scaling and root planing; Endodontic treatment
Intervention type(s): Procedure; Other
Intervention description(s): Scaling and root planing was done in both the groups; In non vital teethRoot canal treatment was completed in two visits. 3% Naocle was used as irritant and calcium hydroxide was used as intracanal medicament .Obturation was done with gutta percha.
Other intervention name(s): Non surgical Periodontal treatment; root canal treatment
Allocation: Non-Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: endodontic treatment; scaling; root planning