Background: Concerns have been raised over the integrity of gloves and the longevity of their protective barrier function. Aims: This study aimed to assess the effect of clinicians' fingernail length as a predisposing factor for perforation of latex gloves. Methods: We assessed 2006 latex examination gloves for perforations using the water inflation method after being used by 6 senior dental students who had fingernail lengths ranging from 0 to 3 mm. Four simulated clinical procedures representing a variety of hand movements were used for this purpose and were repeated 30 times, followed by a water leakage assessment test. Data were analysed using the χ 2 test, analysis of variance and logistic regression. Results: Leakage was detected in 222 (11.1%) gloves, and was most frequent with longer fingernails (odds ratio =1.431, 95% confidence interval 1.249-1.640; P < 0.001). This was independent from the simulated clinical procedure. Most perforations were over the index fingers and thumbs (63.5% and 24.3%, respectively; P < 0.001). The simulated procedures with most perforations were wiping the scaler tip with gauze (20.8%) and placing the chamfer bur (15.3%). The procedure with the fewest perforations was placing the triple way syringe (3.5%). Conclusion: The length of the clinicians' fingernails significantly compromises the integrity of latex gloves. Maintaining short fingernails is important in reducing the risk of damaging latex gloves intraoperatively, and hence maintaining the barrier function of the gloves.