Pakistan Oral Cancer Collaborative: analyzing barriers and obstacles to oral cancer diagnosis, treatment, and prevention in Pakistan.

Oral cancer is a global health problem with increasing case numbers worldwide and no significant improvement in prognosis over the last few decades. It is one of the most common cancers and a leading cause of death in Pakistan, although the number reported is significantly underreported owing to the lack of a national cancer repository, and the true magnitude of this challenge is not known. Bilateral discussions and workshops funded by the Global Challenges Research Fund brought together a number of like-minded researchers and clinicians from the United Kingdom and Pakistan to analyze the status quo and plan the future course. This article reviews some of these discussions as well as barriers to oral cancer diagnosis in Pakistan and makes recommendations to investigate the magnitude and develop measures that may help tackle this devastating disease.

Treatment of caries affected dentin with different photosensitizers and its effect on adhesive bond integrity to resin composite.

OBJECTIVE: The aim of the present study was to evaluate the effect of different photosensitizers activated by photodynamic therapy (PDT) on shear bond strength (SBS) of composite resin on caries affected dentin compared to conventional cavity disinfectants. MATERIALS AND METHODS: Forty carious mandibular teeth were collected through non-traumatic extraction. All samples were embedded in polyvinyl cross-sections to the cemento-enamel junction. The preparation of caries-affected dentin was performed by grinding the specimens using silicon carbide discs. All specimens were arbitrarily allocated in to four groups (n = 10). Group 1, affected dentin disinfected with methylene blue (MB) [100 mg/L]; Group 2, caries affected dentin disinfected using curcumin photosensitizer (CP) [500 mg/L]; Group 3, affected dentin disinfected with indocyanin green photosensitizer (ICGP) [0.5 mL] Group 4, affected dentin treated with 3 % H2O2. Two-step self-etch adhesives was smeared on all specimens for 15 s and photopolymerized for 10 s. All specimens were placed in an incubator with humid environment for 24 h at 37 °C followed by positioning in universal testing machine for SBS testing. Failure mode examination of debonded samples was performed by a stereomicroscope. Analysis of variance (ANOVA) was used for inter group comparison through mean and standard deviation of each group. For multiple group comparison Tukey HSD was employed. Level of significance was established at p < 0.05. RESULT: In group 2 dentin disinfection using CP, displayed the highest SBS value (18.21 ± 1.39 MPa). Whereas, group 4 (3% H2O2 as cavity disinfectant) presented the lowest SBS values (13.39 ± 1.26 MPa). SBS in Group 3 (ICGP) (17.42 ± 0.55 MPa) specimens was comparable to group 2 (p > 0.05) samples. In group 1, samples disinfected with MB (15.18 ± 0.39 MPa) was found to be significantly lower compared to group 2 and group 3 (p < 0.05) respectively. CONCLUSION: Curcumin and Indocyanin green (ICGP) PS have the potential to be used as cavity disinfectant as it improves SBS of caries affected dentin to resin composite. Photodynamic therapy for disinfection of caries affected dentin will augment its bond strength, however its long-term effect on bond integrity still needs to be investigated.

Bond strength of root canal filling with radicular dentin previously treated with either photobiomodulation or photodynamic therapy: Effect of disinfection protocols.

PURPOSE: The aim of the present study was to establish an assessment regarding the efficacy of final disinfection protocols and sealers on the bond strength (BS) of root canal (RC) filling materials on root dentin which has already been treated with photobiomodulation (PBT) or photodynamic therapy (PBT) respectively. METHODS: One-hundred and twenty root canals were included in the present study. The selected teeth were cleaned and shaped to accept the obturation. The prepared specimens were subjected to laser therapy (PBT and PDT) and were randomized into three groups (n = 20/group) on the basis of irrigation technique: Group 1: distilled water (DW) + ultrasonic irrigation (UI); Group 2: 17 % EDTA; Group 3: 0.2 % Chlorhexidine digluconate (CHx) respectively. Each specific group was further divided into two subgroups (n = 10), based on endodontic sealing agent incorporated during obturation: AH Plus or MTA Fillapex. The push-out test was used to gauge the BS, whereas the evaluation was done with the help of two-way ANOVA which was followed by a subsequent Tukey post-hoc test. The chi-square test was used to calculate the mode of failure in the selected specimens (α = 5%). RESULTS: The final irrigation protocols of 17 % EDTA and CHX helped to enhance the BS of RC filling material with either sealer agent used (p < 0.05), whereas, AH Plus reported an increase in the values of BS as compared to its counterpart, MTA Fillapex (p < 0.05). Increased values of cohesive failure were associated with all the groups, irrespective of the tested final irrigation protocols and RC sealer agents (p < 0.05). There was no significant difference between the laser therapies among all the groups (p < 0.05). CONCLUSIONS: The use of 17 % EDTA and CHX and sealing material AH Plus increased the BS of the obturation on radicular dentin previously subjected to either of the mentioned laser therapies. Furthermore, no significant effect on the BS was observed with the use of lasers in the study.

Clinical efficacy of photodynamic therapy and laser irradiation as an adjunct to open flap debridement in the treatment of chronic periodontitis: A systematic review and meta-analysis.

BACKGROUND: The aim of this systematic review and meta-analyses was to assess the quality of evidence and efficacy of antimicrobial photodynamic therapy (aPDT) and laser irradiation (LI) as an adjunct to open flap debridement (OFD) in the treatment of chronic periodontitis. METHODS: Electronic searches were conducted in databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Cochrane Oral Health Group Trials Register databases) up to March 2019. Randomized clinical trials (RCTs) comparing clinical efficacy of either aPDT and/or LI, placebo, or no treatment were included. Primary outcomes included clinical attachment level (CAL), while secondary outcomes were reduction in probing depth (PD) and gingival recession (GR) depth. The weighted mean differences (WMD) of outcomes and 95% confidence intervals (CI) for each variable were calculated using random effect model. RESULTS: Six RCTs were included. For aPDT studies, the overall mean difference for CAL gain (WMD = -0.61, 95% CI = -1.22 to -0.016, P = .044) and PD reduction (WMD = -1.79, 95% CI = -3.44 to -0.14, P = .034) was significant between aPDT and OFD groups at follow-up. No significant overall mean difference was observed for GR depth (WMD = 0.02, 95% CI = -0.75 to 0.79, P = .95). For LI studies, none of the clinical periodontal parameters including CAL gain (WMD = 0.23, 95% CI = -0.09 to 0.55, P = .159, Figure 3A), PD reduction (WMD = 0.31, 95% CI = -0.67 to 1.31, P = .52, Figure 3B) and GR depth (WMD = -0.34, 95% CI = -2.47 to 1.78, P = .74, Figure 3C) were found to be significant between LI and OFD groups at follow-up. CONCLUSION: With the limited data available, only aPDT as an adjunct to OFD showed superior results for clinical periodontal parameters compared to OFD alone in the treatment of chronic periodontitis. Further RCTs are warranted in order to obtain robust conclusions with regard to laser therapy.

Ethnicity and perception of dental shade esthetics.

AIM AND OBJECTIVES: To determine whether or not people from different ethnic backgrounds have different attitudes towards dental esthetics and chose different dental appearances in terms of tooth shade, and to determine whether the dental professional's choice and the individual's own choice have any relationship with what the individual ideally perceives as esthetically pleasing. METHODOLOGY: For this cross-sectional analytical study, 120 volunteer students from the University of Sheffield (excepting dental students) from various ethnic backgrounds, of different ages, of both genders, and with varying degree/educational levels were recruited from the campus. The volunteers were asked to complete a questionnaire containing 9 adapted attitudinal statements regarding positive or negative dental esthetic perceptions in terms of tooth shade, with responses on a 5-point Likert scale from "Entirely agree" to "Entirely disagree". Scores for all attitudinal statements were summed up to give an attitudinal score. The participants' ideal, perceived, and actual (self-assessed and investigatorassessed) tooth shade was also determined using a shade guide and a facial mirror. RESULTS: No association between ethnicity and attitudinal score was found. However, statistically significant associations were found between the participants' degree/educational level (P=0.004, 95% Confidence Interval (CI)=-4.18 to -0.82) and their ideal tooth shade value (P=0.038, 95% CI=-3.53 to -0.11). There were strong correlations between self-assessed and professionally assessed tooth shade value in all ethnic groups, with Spearman's rank correlation coefficient (rho) being ρ>0.6. Regarding ideally desired and perceived tooth shade value, weak correlations were found in all ethnic groups (Spearman's rho being ρ<0.4). CONCLUSION: Although no significant association was found in this sample between ethnicity and attitude towards dental esthetics with regard to tooth shade, both ethnicity and dental esthetics are very diverse terms with multiple dimensions, each of which needs further investigation with regard to their mutual association.