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Известия на Съюза на учените – Варна. Серия „Медицина и екология”

The correlation between the rotation of upper first permanent molars and malocclusions in the individual dental arch and in the occlusion

Gergana Ivanova, Hristina Arnautska, Zornitsa Valcheva, Iliyana Atanasova



Malocclusions disturb the integrity of the dental arch and the interdental/occlusal relationship. All this leads to a change in the position of the upper molars in the sagittal, transversal and vertical plane. The rotation of the upper first molar leads to a shift of position of molar cups in a mesio-distal direction demonstrated by the great impact on the distribution of occlusal forces.


The rotation of upper first molars should not be underestimated in the biometrical analysis of diagnostic dental casts as this can lead to incomplete and improper treatment plan.

Мaterials аnd Methods

Our study investigated 681 children aged 7-10 years who attended the Department of Orthodontics at the Faculty of Dental Medicine in Varna. All children were clinically evaluated and biometrical assessment of diagnostic dental casts was performed. Diagnostic records included also photo-analysis and measurements of diagnostic dental casts. The relationship between the rotation of upper first permanent molars and the transversal and sagittal dimension, and also the overjet were assessed. The degrees of rotation were classified using the Friel and Vigano methods.


A regressional statistical analysis was conducted to determine the frequency of malocclusion and to establish the relationship between the rotation of upper first permanent molar and the length of the arch, the intercanine distance, and the overjet. The comparative analysis demonstrated inverse relationship not only between the rotational position of the molars and the length of the arch, but also between the canine distance and the rotation of the upper molars (p<0.01). It is reported that when an overjet up to 4 mm is present,  the mediopalatal rotation of the molars is negatively affected.


Losing the length of the arch leads to compression of the dental arch, medialization of permanent molars and crowding of the frontal teeth. The problem of mesiopalatal rotation of upper first permanent molars is manifested through increased overjet and increased overbite.


rotation; upper first permanent molar; Friel method; Vigano method; length of the dental arch; intercanine distance; overjet

Full Text


Андреева Л, Показания за ортодонтско лечение на зъбните дъги в ранно смесено съзъбие. Дисертация за получаване на образователна и научна степен„доктор, София, Стоматологичен факултет 2002

Андреева-Гургуриева Л ,Значение на интерканиновото разстояние за стабилността на ортодонтско лечение. Дисертация за придобиване на НС Доктор на науките, София, 2017

Миргазьiзов МЗ, Колотков АП, Королева АА, Прогнозирование размеров постоянньiх кльiков и премоляров в I фазе сменного прикуса и методика определение места в зубном реду при скучености зубов.- Б. Информационньiй листок, Кемерово 1973

Петрунов В. Епидемиологично проучване на зъбно-челюстните деформации и необходимостта от ортодонтско лечение при българи в периода от смесено до постоянно съзъбие. Дисертация за получаване на образователна и научна степен доктор. София, Стоматологичен факултет, 2012, 105с

Andrews, L. F.: The six keys to normal occlusion, Am. J. Orthod. 61:297, 1972

Braun S, Kusnoto B, Evans CA. The effect of maxillary first molar derotation on arch length. Am J Orthod Dentofacial Orthop 1997;112:538–44

Carlon JA 1973 Die Rotation des ersten Oberkiefermolaren. Informationen aus Orthodontie und Kieferorthopadie 2: 137-162

Cattaneo, PM., Dalstra M., Melsen, B, The Transfer of occlusal forces through the maxillary molars: A finite element study. Am J. Orthod Dentofacial Orthop. 2003; 123, No. 4: 367-373

Dahlquist A, Gebauer U, Ingervall B, The effect of a transpalatal arch for the correction of first molar rotation, European Journal of Orthodontics, 1996, vol. 18, no. 3, pp. 257–267

Friel S. Determination of the angle of rotation of the upper first molar to the median raphe of the palate in different types of malocclusion. Dental Practitioner. 1959;9:72-8

Giuntini V, Baccetti T, Defraia E, Cozza P, Franchi L, Mesial rotation of upper first molars in Class II division 1 malocclusion in the mixed dentition: acontrolled blind study,Progress in Orthodontics, 2011, vol.12,no.2,pp.107–113

Lima BP, MaioPinzan-Vercelino CR, Dias LS, Bramante FS, De Jesus Tavarez RR, Correlation between the Rotation of the First Molars and the Severity of Class II Division 1 Malocclusion,1 June 2015 Hindawi Publishing Corporatione Scientific World Journal Volume 2015, Article ID 261485, 5 pages

Naushada H., Shaheedb S, Zahrac S, Banod S, Maxillary first molar rotation and its relationship with skeletal and occlusal discrepancies, POJ 2014:6(2) 43-47

Norman PM, Henry G., Elsbach. Functional maintenance of arch-length. J Dent Child, May-June 1980; 190-193

Stoller AE. The normal position of maxillary first permanent molar. Am J Orthod. 1954;40:259–271

Viganó CO, Ekerman da Rocha V, Menezes Junior LR, Paranhos LR, Ramos AL, Rotation of the upper first molar in Class I, II, and III patients. Eur J Dent. 2016 Jan-Mar; 10(1): 59–63



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