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A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study

Janak Lodha , Tarun Sharma , P. Narayana Prasad , Anupa Rawat , Sumit Joshi , Arushi Mishra

Pages 48-53 Published 16 July 2026 DOI 10.65929/JSAD.2026.1.2.004 Rights held by the authors
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Abstract

Background: Subtle but measurable changes in craniofacial morphology persist beyond biological maturity. Transverse dimensions of the dental arch, such as intermolar and intercanine widths, are important for functional occlusion and esthetics. The determination of angular relationships among important maxillary landmarks may be helpful in orthodontic diagnosis, treatment planning, and establishment of population-specific norms.

Aim: To determine and record the angular ratio at the diagonal junction of the maxillary canine and maxillary first molar in untreated North Indian subjects with Angle’s Class I malocclusion based on Andrews’ six keys of occlusion.

Materials and Methods: This prospective photogrammetric study included 64 participants (34 males, 30 females) aged 16–25 years from the outpatient department. Standardized intraoral occlusal photographs were captured using a Canon EOS 1500D DSLR camera with a 100 mm macro lens and ring flash. Angles between the maxillary canine cusp tip and the contralateral mesiobuccal cusp tip of the first molar were measured using Adobe Photoshop software. Data was analyzed using SPSS version 21.0 with a 95% confidence interval. A p-value < 0.05 was considered statistically significant.

Results: The mean intermolar angle was 130.50 ± 3.04°, and the mean canine–molar angle was 49.83 ± 3.02°. There was no statistically significant difference between males and females for either the intermolar (p = 0.370) or the canine–molar angle (p = 0.631).

Conclusion: There was no significant difference in the measured angular parameters with respect to gender, indicating a similar craniofacial pattern in the North Indian population. The angular values thus obtained can be used as normative values for future anthropometric and orthodontic studies. More studies on different face forms are suggested to increase its clinical relevance.

Dates & metrics

Received
25 Mar 2026
Accepted
28 Jun 2026
Published
16 Jul 2026
128 views
124 downloads

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Keywords: Maxillary arch Photogrammetry Intermolar angle Canine–molar angle North Indian population Orthodontic analysis

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How to cite this article

Lodha J, Sharma T, Prasad PN, Rawat A, Joshi S, Mishra A. A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study. J. Sci. Adv. Dent. 2026;1(2):48-53. doi:10.65929/JSAD.2026.1.2.004

RIS BibTeX EndNote

Lodha, J., Sharma, T., Prasad, P. N., Rawat, A., Joshi, S., & Mishra, A. (2026). A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study. Journal of Scientific Advances in Dentistry, 1(2), 48-53. https://doi.org/10.65929/JSAD.2026.1.2.004

RIS BibTeX EndNote

Janak Lodha, Tarun Sharma, P. Narayana Prasad, Anupa Rawat, Sumit Joshi, and Arushi Mishra. "A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study." Journal of Scientific Advances in Dentistry, vol. 1, no. 2, 2026, pp. 48-53. https://doi.org/10.65929/JSAD.2026.1.2.004

RIS BibTeX EndNote

Janak Lodha, Tarun Sharma, P. Narayana Prasad, Anupa Rawat, Sumit Joshi, and Arushi Mishra. "A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study." Journal of Scientific Advances in Dentistry 1, no. 2 (2026): 48-53. https://doi.org/10.65929/JSAD.2026.1.2.004

RIS BibTeX EndNote

Lodha, J., Sharma, T., Prasad, P. N., Rawat, A., Joshi, S., and Mishra, A. (2026) 'A novel approach for establishing angular ratio at the diagonal junction between the maxillary canine and maxillary first molar- A prospective photogrammetric study', Journal of Scientific Advances in Dentistry, 1(2), pp. 48-53. https://doi.org/10.65929/JSAD.2026.1.2.004

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© 2026 the authors. Published by REVO Publication. This article is distributed under CC BY 4.0, which permits use and redistribution provided the original work is properly cited.