# Assessment of Number of Cusps and Occlusal Groove Pattern in the Primary Mandibular Molars: An Observational Study

## TL;DR

This study examines the number of cusps and groove patterns in primary mandibular molars of children to understand dental anatomy variations.

## Contribution

The study provides new data on cusp and groove patterns in primary mandibular molars specific to the Nepali population.

## Key findings

- 38.94% of left primary mandibular first molars had four cusps and a 'Y' groove pattern.
- The 'Y' groove pattern was more common in the Nepali population compared to other patterns.
- Results suggest a conservative pattern of deciduous molars in this population.

## Abstract

Primary mandibular molars have diverse morphological variations. This trait of human dentition is very important for restoring the anatomy of the tooth as well as for the anthropological study to characterize the ethnicity. Anatomical landmarks like the cusp, groove and ridges vary even among same species. The study was aimed to assess the number of cusps and occlusal grooves in primary mandibular molars of children.

An observational cross-section study was conducted among pediatric patients in the Outpatient Dental Department of a tertiary care center from October 2023 to March 2024. Fully erupted primary mandibular molars in children aged 3-6 years were included. Intraoral examination of the patient were performed using Gregory WK criteria. A convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval.

Among 303 patients, the study showed 118 (38.94%) left and 106 (34.98%) right primary mandibular first molar had four cusps and a ‘Y’ groove pattern. Among the 303 subjects, male 58 (34.12%) were having a 4Y pattern followed by 46 (27.06%) 4X pattern, while in 48 (36.09%) 4Y pattern followed by 45 (33.83%) 4X pattern was seen.

The result in present study showed Y groove pattern in occlusal surface of primary mandibular molars with four cusps that can be related with conservative pattern of deciduous molar in context of Nepali population.