The Journal of Advanced Prosthodontics

The Korean Academy of Prosthodonitics (대한치과보철학회)
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Three-dimensional morphometric study on the retromolar pad

  • Min-Sang Cha (Department of Dentistry, Gangneung Asan Hospital, University of Ulsan College of Medicine) ;
  • Dae-Gon Kim (Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University) ;
  • Yoon-Hyuk Huh (Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University) ;
  • Lee-Ra Cho (Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University) ;
  • Chan-Jin Park (Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University)
  • Received : 2023.10.04
  • Accepted : 2023.12.15
  • Published : 2023.12.29
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Abstract

PURPOSE. The aim of this study was to classify the shapes of retromolar pads and assess their morphometric differences using a 3D model. MATERIALS AND METHODS. Two hundred fully edentulous or Kennedy Class I partially edentulous patients (400 retromolar pads) were enrolled. Scan data of the definitive mandibular casts produced through functional impressions were obtained using a 3D laser scanner. Seven parameters (transverse diameter, longitudinal diameter, transverse-contour length, longitudinal-contour length, longitudinal/transverse diameter ratio, longitudinal/transverse-contour length ratio, and angle of the retromolar pad line to the residual alveolar ridge line) were measured using image analysis software. Subsequently, the pads were classified according to the shape. Statistical analyses were performed using 95% confidence intervals. RESULTS. Classifying the retromolar pads into three shapes led to high intra-examiner reliability (Cronbach's alpha = 0.933). The pear shape was the most common (56.5%), followed by oval/round (27.7%) and triangular (15.8%) shapes. There were no significant differences between the left and right sides according to the shape and no significant differences in any parameter according to age. The transverse diameter and longitudinal/transverse diameter ratio differed between sexes (P < .05). The triangular shape had a significantly different transverse diameter, transverse-contour length, longitudinal/transverse diameter ratio, and longitudinal/transverse-contour length ratio compared with the pear and oval/round shapes (P < .05). CONCLUSION. From a clinical reliability standpoint, classifying retromolar pads into three shapes (oval/round, pear-shaped, and triangular) is effective. The differences in the sizes among the shapes were attributed to the transverse measurement values.

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References

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