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Objective. To investigate the correlation of periodontal parameters and bite force in different stages of periodontitis after phase I periodontal therapy. Methods. Periodontal clinical parameters such as mobility, attachment loss, gingival recession, and percentage of bone remaining were recorded at the mandibular first molar region after phase I therapy in subjects categorized according to the stage of periodontitis. Corresponding bite force was recorded at the first mandibular molar region using a bite force device after phase I therapy. ANOVA test was used to assess the significant difference among different groups. Pearson correlation coefficient was used to assess the correlation between measured variables. Results. The ANOVA test represents that there is no statistical significant difference between the bite force in stage I, stage II, and stage III type of periodontitis. A strong positive correlation was found ( r = 0.537 ) between bite force and percentage of remaining alveolar bone support whereas negative correlation was observed in measured parameters such as mobility ( r = − 0.0181 ), attachment loss ( r = − 0.608 ), and gingival recession ( r = − 0.435 ). Conclusion. Among all periodontal clinical parameters, the percentage of remaining alveolar bone is the strong predictor of bite force and mobility; attachment loss and gingival recession cannot predict the bite force in the first molar region. Bite force is variable in different stages of periodontitis.

Visual inspection and gingival indices have been traditionally used for diagnosis of gingival inflammation. These methods are prone for subjective variability. Thus, the study is aimed at evaluating gingival inflammation quantitatively by using CIELab colour space value obtained from digital photographs. An experimental study was conducted with 27 patients each in group A (gingivitis) and group B (chronic periodontitis, CP). Preoperative and postoperative (1 month) photographs of maxillary anterior sextant were recorded to evaluate CIELab coordinate values. Simultaneously, clinical parameters such as bleeding on probing (BOP) and periodontal probing depth (PPD) along with indices such as plaque index (PI), gingival index (GI), and sulcus bleeding index (SBI) were evaluated before and after the nonsurgical periodontal therapy. Data was presented as the mean ± SD , and a paired t -test was used for the testing hypothesis with p < 0.05 considered as significant. Data analysis was carried out with Statistical Package for the Social Sciences (SPSS) version 21. A significant reduction ( p < 0.001 ) is seen in all the clinical parameters and indices before and after the intervention in chronic periodontitis patients. Similar results were seen in gingivitis patients ( p < 0.001 ) except for PPD. A significant ( p < 0.001 ) reduction in postoperative values of the a ∗ and b ∗ coordinates was seen in CP patients; whereas, only the a ∗ coordinate value reported a significant ( p < 0.001 ) reduction in the gingivitis group of patients. The Δ E of the gingivitis and chronic periodontitis groups was 2.25 and 2.96, respectively. Within the confinements of the study, estimating the gingival colour with the help of CIELab values taken via digital photographs can be an excellent valuable tool to assess the gingival colour as a sign of gingival inflammation.

The present study was aimed at reviewing the studies that used finite element analysis (FEA) to estimate the biomechanical stress arising in removable partial dentures (RPDs) and how to optimize it. A literature survey was conducted for the English full-text articles, which used only FEA to estimate the stress developed in RPDs from Jan 2000 to May 2021. In RPDs, the retaining and supporting structures are subjected to dynamic loads during insertion and removal of the prosthesis as well as during function. The majority of stresses in free-end saddle (FES) RPDs are concentrated in the shoulder of the clasp, the horizontal curvature of the gingival approaching clasp, and the part of the major connector next to terminal abutments. Clasps fabricated from flexible materials were beneficial to eliminate the stress in the abutment, while rigid materials were preferred for major connectors to eliminate the displacement of the prosthesis. In implant-assisted RPD, the implant receive the majority of the load, thereby reducing the stress on the abutment and reducing the displacement of the prosthesis. The amount of stress in the implant decreases with zero or minimal angulation, using long and wide implants, and when the implants are placed in the first molar area.