Prognosis of root canal treatment in teeth with preoperative apical periodontitis: a study with cone-beam computed tomography and digital periapical radiography.

AIM: This observational cohort study aimed: (i) to determine retrospectively after a 1- to 12-year follow-up period, the strength and independence of the association of various patient-, tooth- and treatment-related prognostic variables with the outcome of root canal treatment in patients with pre-therapeutic apical periodontitis; and (ii) to establish the concordance between those predictors evaluated by both cone-beam computed tomography (CBCT) and digital periapical radiography (DPR). METHODOLOGY: The study cohort included 125 teeth in 84 individuals. The postoperative clinical signs/symptoms, plus DPR/CBCT-PAI estimations, were used to determine the healing outcome. For statistical analysis, results were dichotomized into completely healed periapical structures versus persistent disease cases. The association between candidate predictor variables with persistent disease was analysed individually and adjusted for confounders using a multivariate binary logistic regression model. RESULTS: The success rate was 53.6%. After logistic regression analysis, mandibular tooth location, periapical lesion size >10 mm, poor quality of the coronal restoration, lack of magnification/illumination, lack of disinfection of gutta-percha, time elapsed to definitive coronal restoration >1 week and poor density of root canal filling remained as robust predictors of failures. Concordance between DPR and CBCT scores varied from moderate to almost perfect agreement. CONCLUSIONS: The findings of this study suggest that several tooth- and treatment-related predictor variables, including tooth location, periapical radiolucency size, quality of the coronal restoration, magnification/illumination, disinfection of gutta-percha, time elapsed to definitive coronal restoration, as well as, the density of root canal filling may act strongly and independently for determining the root canal treatment outcome in teeth with pre-therapeutic apical periodontitis.

Association study between salivary levels of interferon (IFN)-gamma, interleukin (IL)-17, IL-21, and IL-22 with chronic periodontitis.

OBJECTIVE: To investigate if the salivary levels of IL-17, IL-21, IL-22, and its ratio regarding salivary IFN-γ may be linked with the periodontal clinical status. DESIGN: One hundred and five chronic periodontitis (CP) subjects and 44 healthy controls (HC) were recruited. Periodontal status was assessed based on full-mouth clinical periodontal measurements. Cytokine salivary levels were analyzed by ELISA. The association between the analytes with CP was analyzed using a binary logistic regression model. RESULTS: A statistically significant increase in salivary levels of IFN-γ and IFN-γ/IL-22 ratio in CP group could be detected, but there was no significant domination of any Th17 cytokine that could be of predictive value for health/disease status. Univariate and binary logistic regression analyses revealed a strong and independent association of IFN-γ salivary levels and IFN-γ/IL-22 ratio with disease status. An interaction effect of ageing on IFN-γ levels also could be noted. CONCLUSION: While salivary levels of IFN-γ and IFN-γ/IL-22 ratio may act as strong/independent indicators of the amount and extent of periodontal breakdown, the low detection frequency of Th17 cytokines in saliva samples make these determinations useless for the detection of disease presence and/or its severity.

Retrospective follow-up assessment of prognostic variables associated with the outcome of periradicular surgery.

AIM: To investigate, retrospectively over a 1- to 16-year follow-up period, the strength and independence of the association of different patient-, tooth- and surgery-related prognostic variables with the outcome of periradicular surgery. METHODOLOGY: The study cohort included 171 teeth in 154 subjects. Clinical and radiographic measures along with the follow-up period were used to determine the healing outcome. For statistical analysis, results were dichotomized into healed/healing versus asymptomatic function/persistent disease cases. The association between candidate prognostic variables and asymptomatic function/persistent disease was analysed individually and adjusted for confounding using a multivariate binary logistic regression model. RESULTS: The percentage of success (healed/healing cases) was found to be 83.6%, whereas the percentage of failure (asymptomatic function/persistent disease cases) was found to be 16.4%. Whilst univariate analysis revealed a positive association of the presence of preoperative signs/symptoms, unsatisfactory quality of the coronal restoration, pronounced root-end resection bevel and inadequate quality of root-end filling with asymptomatic function/persistent disease, after multivariate binary logistic regression analysis only the unsatisfactory quality of the coronal restoration and inadequate quality of root-end filling were strongly and independently associated with disease status. Confounding and interaction effects between candidate prognostic variables was noted. CONCLUSIONS: The findings of this study suggest that whilst the quality of both the coronal restoration and the root-end filling might be the foremost prognostic variables in periradicular surgery, there are synergistic biological interactive and mutually confounding effects with respect to root-end resection bevel and preoperative signs and/or symptoms that may be also associated with an increased proportion of failures after periradicular surgery.

Confounding and interaction effect of Treponema denticola salivary carriage in chronic periodontitis.

AIM: To evaluate the salivary carriage of Treponema denticola and its association with demographic variables in the etiopathogenesis of chronic periodontitis. SUBJECTS AND METHODS: Ninety-seven chronic periodontitis (CP) patients and a control group of 51 healthy subjects (HC) were selected. Periodontal status was assessed by criteria based on probing depth, attachment loss, extent, and severity of periodontal breakdown. A polymerase chain reaction method was used to determine the occurrence of T. denticola in saliva samples. Risk indicators for CP were assessed individually and adjusted for confounding and/or interaction using a logistic regression model. RESULTS: Although univariate analysis revealed a positive association of age >or=30 years, smoking, and salivary carriage of T. denticola with CP, after logistic regression analysis, the association between age >or=30 years/smoking and CP persisted, whereas salivary carriage of T. denticola failed to achieve statistical significance. An interaction effect was significantly detected between these three variables. CONCLUSION: Although salivary carriage of T. denticola may be a risk indicator for CP, its pathogenicity should not be exclusively endorsed to its detection in saliva, but it might be associated with the synergistic biological interaction of the bacterium with some demographic characteristics of the susceptible host.

Estimation of sCD14 levels in saliva obtained from patients with various periodontal conditions.

AIM: To assess the concentration of soluble CD14 receptor in saliva of people with periodontal disease and healthy patients and its relationship with periodontal status. SUBJECTS AND METHODS: Unstimulated whole saliva samples from patients with chronic periodontitis (n = 34), aggressive periodontitis (n = 19) and healthy controls (n = 17) were obtained for the study. The periodontal status of each subject was assessed by criteria based on probing depth, clinical attachment loss and the extent of periodontal breakdown. The levels of sCD14 were measured in saliva samples with an enzyme-linked immunosorbent assay (ELISA). RESULTS: Although no significant difference (P > 0.05) was found for salivary sCD14 levels between periodontitis groups, they were significantly greater (P < 0.05) than those detected for healthy controls. Furthermore, Spearman's correlation analysis showed statistically significant correlations (P < 0.01) between data from salivary sCD14 levels and clinical measurements. CONCLUSION: The findings of the present study reemphasize the importance of whole saliva as sampling method in terms of immunological purposes in periodontal disease and suggest that the elevated sCD14 concentration may be one of the host-response components associated with the clinical manifestations of periodontal disease.

Correlation between salivary IL-1beta levels and periodontal clinical status.

OBJECTIVE: To assess the concentration of the proinflammatory cytokine IL-1beta in saliva of periodontally diseased and healthy patients and their relationship with the periodontal status. DESIGN: Unstimulated whole saliva samples from patients with chronic periodontitis (n=30), aggressive periodontitis (n=18) and healthy controls (n=18) were obtained for the study. The periodontal status of each subject was assessed by criteria based on probing depth, clinical attachment loss and the extent/severity of periodontal breakdown. The levels of IL-1beta were measured in saliva samples with a high sensitivity enzyme-linked immunosorbent assay (ELISA). RESULTS: Although no significant difference (P=0.624) was found for salivary IL-1beta levels between periodontitis groups, they were significantly greater (P<0.01) than those detected for healthy controls. Furthermore, Spearman correlation analysis showed statistically significant correlations (P<0.01) between data from salivary IL-1beta levels and clinical measurements. CONCLUSION: The findings of the present study reemphasize the importance of whole saliva as sampling method in terms of immunological purposes in periodontal disease and suggest that the elevated IL-1beta concentration may be one of the host-response components associated to the clinical manifestations of periodontal disease.

Ex vivo microscopic assessment of factors affecting the quality of apical seal created by root-end fillings.

AIM: (i) To evaluate the incidence of microcracks around root-end preparations completed with ultrasonic tips and their relationship with the root filling technique and thickness of surrounding dentine. (ii) To investigate the effect of rapid exposure to a water-soluble dye of Intermediate Restorative Material (IRM), Super Ethoxybenzoic Acid (sEBA) and Mineral Trioxide Aggregate (MTA), on the marginal adaptation and microleakage of root-end fillings. (iii) To describe the microstructure of the surface of root-end filling materials. METHODOLOGY: Ninety-two single-rooted teeth were divided into two groups (n = 46) according to the root canal instrumentation/filling techniques. Group 1 consisted of specimens in which canal preparation was completed using a crown-down technique and then filled with the Thermafil system (TF group); Group 2 consisted of specimens in which canal preparation was completed using a step-back technique and lateral condensation (LC group). Following root-end resection and ultrasonic cavity preparation, the samples were further divided into three subgroups (n = 24) for root-end filling with IRM, sEBA or MTA. The ultrasonic preparation time was recorded. Eight teeth were kept as positive and 12 as negative controls. Following immersion in Indian ink for 7 days, all resected root surfaces were evaluated for the presence of microcracks and the cross-sectional area of root-end surface and root-end filling were measured to evaluate the thickness of the dentinal walls. Thereafter, the samples were sectioned longitudinally so as to assess the depth of dye penetration and marginal adaptation of root-end fillings. Negative controls longitudinally sectioned were used to describe microstructural characteristics of the root-end filling materials using scanning electron microscopic (SEM) techniques. RESULTS: Although the thickness of dentinal walls between groups 1 and 2 was similar, the ultrasonic preparation time and number of microcracks were significantly higher (P < 0.001) in the TF group. Both groups had a significant correlation between microcracks and ultrasonic preparation time (P < 0.001). sEBA and IRM had better adaptation and less leakage compared with MTA. A SEM analysis displayed microstructural differences between the root-end filling materials. CONCLUSION: Microcracks can occur independently of the thickness of dentinal walls and may be associated with the prolonged ultrasonic preparation time required for the removal of the root filling during root-end cavity preparation. Although sEBA and IRM had better behaviour than MTA regarding microleakage and marginal adaptation, it is possible that exposure of MTA to a water-soluble dye before achieving full set and its porous microstructure contributed to the results.

Healing response of apicomarginal defects to two guided tissue regeneration techniques in periradicular surgery: a double-blind, randomized-clinical trial.

AIM: To compare healing responses to periosteal sliding grafts and polyglactin 910 periodontal mesh used as guided tissue regeneration (GTR) materials/techniques when both periapical and periradicular bone loss are present. METHODOLOGY: Thirty patients with suppurative chronic apical periodontitis with apicomarginal communication were selected and allocated randomly into two groups according to the barrier technique to be used during periradicular surgery: periosteal graft group (n = 15) and bioabsorbable membrane group (n = 15). Clinical and radiological evaluations were completed prior to surgery, a week later and every 3 months after surgery up to 12 months to measure the periodontal pocket depth (PD), clinical attachment level (CAL), gingival margin position (GMP), size of periapical lesion, percentage reduction of the periapical rarefaction, and periapical healing. RESULTS: Both groups showed highly significant (P < 0.001) reductions in periodontal PD, CAL and size of periapical lesion at 12 months whilst GMP was unaltered. No significant difference between the experimental groups was evident for these parameters, or for the percentage reduction of size of the periapical lesion and clinical-radiographic healing. CONCLUSION: Guided tissue regeneration applied to apicomarginal defects using sliding periosteal grafts and use of bioabsorbable membranes led to similar enhancements of the clinical outcome of periradicular surgery in terms of periapical healing, gain of periodontal support, PD reduction and minimal recession of the gingival margin.

Periosteal grafts as barriers in periradicular surgery: report of two cases.

AIM: To describe the usefulness of periosteal grafts as barriers for bone regeneration in periradicular surgery when advanced periodontal breakdown occurs. SUMMARY: The treatment of advanced periodontal breakdown as a result of an associated endodontic lesion constitutes a multifaceted challenge to the clinician. If the source of the irritation cannot be removed by orthograde endodontic treatment, nonsurgical and surgical endodontic/periodontal intervention may be required. Two cases with suppurative chronic apical periodontitis with apicomarginal communication are described. Clinical and radiological evaluations were completed immediately prior to surgery, a week later and every 2 months after surgery for 10 months. Both patients were treated using split-thickness flaps and lateral displacement of the periosteum prior to suturing, in order to close the communication between the oral and the periapical surroundings. A remission of the clinical signs and symptoms, and successful healing in the short-term were achieved in these cases. KEY LEARNING POINTS: Periapical and periodontal lesions are closely related through pathways of communication. Disruption of the cortical plate and the presence of dentoalveolar sinus tracts can have a deleterious effect on the regeneration process after periradicular surgery. The adoption of supplementary periodontal surgical techniques may help to solve some of the difficulties in the healing process in periradicular surgery. Periosteal grafts have been shown to have the potential to stimulate bone formation when used as a graft material.

Expression of caspase-3 and structural changes associated with apoptotic cell death of keratinocytes in oral lichen planus.

OBJECTIVE: Apoptosis appears to be the mode of cell death by which damaged cells are removed from the lesional tissue. The aim of this study was to examine keratinocyte apoptosis and caspase-3 (CPP32) expression in oral lichen planus (OLP). MATERIALS AND METHODS: Paraffin-embedded samples of OLP (n = 30) and normal oral mucosa (NOM; n = 5) were prepared for haematoxylin-eosin (H & E), immunohistochemistry and electron microscopy. The number of apoptotic cells and the proportion of total cells that were either apoptotic (apoptotic index; AI) or mitotic (mitotic index; MI) were assessed in H & E stained sections. An immunostaining-intensity-distribution index (IIDI; proportion of stained cells x staining intensity) was used to assess CPP32 immunoreactivity. RESULTS: Results showed a significant increase in the number of apoptotic cells in OLP (P < 0.001). In OLP, all apoptotic bodies were found in the basal and prickle epithelial layers. Compared with NOM, the AI was significantly greater in atrophic (P < 0.05), reticular (P < 0.001) and plaque-like (P < 0.01) OLP. The MI was significantly greater in plaque-like OLP (P < 0.01). The proportion of CPP32-positive cells and the IIDI were significantly greater in all forms of OLP compared with NOM (P < 0.05). No difference in CPP32 expression was evident between clinical forms of OLP. Electron microscopy confirmed the light microscopic finding of apoptosis. CONCLUSION: Keratinocyte apoptosis and caspase-3 expression co-localized to the basal and parabasal epithelial layers, suggesting that proliferating epithelial cells may be targeted for destruction in OLP. Differences in epithelial AI and MI may underlie the various clinical and histological appearances of OLP.