Bolton ratio
The Bolton ratio, also known as the tooth-size discrepancy, is a measurement used in dentistry to assess the relationship between the sizes of upper and lower teeth in the dental arch. It helps in determining whether there is a proportionate match between the sizes of teeth in the maxillary (upper) and mandibular (lower) arches. The Bolton ratio is important for achieving proper occlusion (bite) and a balanced dental arch. The Bolton ratio is calculated by dividing the sum of the mesiodistal (width) measurements of the teeth in one dental arch by the sum of the mesiodistal measurements of the corresponding teeth in the other arch. **Formula for Calculating Bolton Ratio:** Bolton Ratio = (Sum of Maxillary Tooth Widths) / (Sum of Mandibular Tooth Widths) The Bolton ratio is expressed as a decimal or percentage. A ratio of 91.3% (0.913) is considered ideal, indicating a harmonious tooth-size relationship between the upper and lower arches. **Clinical Significance:** - **Excess