Modified Difficulty Index Adding Extremely Difficult for Mandibular Third Molar Extraction
DOI:
https://doi.org/10.51985/Keywords:
Impacted, Molar, Third, Radiography, Panoramic, Mandible, Surgical Difficulty IndexAbstract
Objective: To evaluate the frequency and distribution of difficulty levels in impacted mandibular third molar extractions using the Modified Difficulty Index (MDI), and to assess intra-observer agreement with the index components.
Study Design and Setting: A cross-sectional study carried out in the Oral & Maxillofacial Surgery department of Foundation University College of Dentistry & Hospital for a six months duration.
Methodology: Consecutive patients (n = 225) with fully impacted mandibular third molars, aged 18–60 years, were enrolled. Panoramic radiographs were scored by a single researcher using the MDI (spatial relationship, depth, ramus/space). MDI scores totalled (3–12) were grouped as slightly, moderately difficult, very difficult, and extremely difficult. Data were analysed with SPSS v27; categorical data as frequencies (%), continuous as mean ± SD; quadratic weighted kappa measured agreement; p = 0.05 is significant.
Results: The mean age was 29.31 ± 8.64 yrs; 86 (38.2%) males and 139 (61.8%) females. Kappa values showed substantial agreement for spatial relationship (0.775), depth (0.744), and ramus relationship (0.663); overall total-score agreement was 0.855. Distribution: Category I 14 (6.2%), II 164 (72.9%), III 34 (15.1%), IV 13 (5.8%). Horizontal impaction (39.1%) and Level B depth (46.7%) were most common. Older age correlated with higher difficulty (P < 0.001).
Conclusion: The Modified Difficulty Index (MDI) demonstrates high intraobserver agreement for radiographic scoring of fully impacted mandibular third molars and describes the distribution of radiographic difficulty categories in this singlecenter sample. A small subset of cases were classified as extremely difficult radiographically.
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