DENTAL ARCH SIZE: SAPIENCE, SCIENCE, SOLUTION

Introduction

The current longitudinal study involved evaluation of 3 transversal parameters of the maxillary arch, affecting the stability of the orthodontic treatment result.



Aim

The aim was to estimate the long-term dynamics of the intercanine distance, anterior arch width and the apical base width of the maxilla.



Materials and methods

145 orthodontic patients were divided in two groups. Group I included 104 subjects; for each maxillary intercanine distance, anterior arch width and apical base width were registered in three time periods:

T1: in the beginning of treatment
T2: after finishing orthodontic treatment
T3: after orthodontic treatment and early retention period 2 – 5 years.
Group II consisted of 41 patients. Periods T1 and T2 were the same as group I; period T3 considered the late retention period – 5 years and over.

In both groups patients were further divided according to dentition stage: early mixed dentition; late mixed dentition; forming permanent dentition; formed permanent dentition; permanent dentition with at least one erupted third molar.



The methods included biometric measurements of the anterior arch width, the apical base width and the intercanine distance plaster study models, introducing an original method.



Results

In group I the maxillary intercanine distance increased with 0.91 mm in T1-T2 and 1.33 mm in the T1-T3. In group II an increment of 1.56 mm in the maxillary intercanine distance for the T1-T2 and 0.89 mm for T2-T3 were observed. For the entire T1-T3 it increased with 2.45 mm. Anterior arch width of the maxilla increased with 6.77 mm in T1-T2 in group I, but remains 6.84 mm in T1-T2 for group II. Apical base of the maxilla has 1.66 mm increase in the early retention period, whereas in late retention period it decreases with 1 mm.



Conclusions

Intercanine distance increased to its maximum during the orthodontic treatment. In the early and late retention period an insignificant increment was observed. Maxillary arch width was significantly increased after orthodontic treatment. In the early and late retention period anterior arch width had a minor increase, clinically insignificant. The apical base in Group I was increased, and in Group II a 1 mm decrement was observed.



Keywords: intercanine distance, arch width dynamics, apical base, retention period

Laura Andreeva, DDS, MDS, PhD, DSc

Laura Andreeva is President of the Bulgarian Orthodontic Society and President of the Balkan Association of Orthodontic Specialist for 2020.

She is Head of the Orthodontics Department and Vice-dean in the Faculty of Dental Medicine, Medical University – Sofia.

Position: Head of Orthodontics Department

Affiliation: Medical University – Faculty of Dental Medicine – Sofia, Department of Orthodontics



Education:

1983 Dental Medicine, Master Degree (DDS)

1990 Master’s degree in Social Medicine and Health Management (MSc)

1992 Orthodontics, Master Degree (MSc)

1996 Resident program in the Orthodontics Department of the University of Liege, Belgium

2003 Educational and Scientific Degree (PhD)

2005 Master’s degree in General dentistry (MSc)

2017 Doctor of Science degree (DSc)



Teaching Activities:

2016 and at present Professor, Department of Orthodontics, FDM – Sofia, Bulgaria

2013 and at present Head of the Department of Orthodontics, FDM – Sofia, Bulgaria

2006 – 2015 Associate professor, Department of Orthodontics, FDM – Sofia, Bulgaria

1995 – 2005 Clinical professor for resident’s program in Orthodontics, Department of Orthodontics, FDM – Sofia, Bulgaria

1992 – 1995 Senior assistant, Department of Orthodontics, FDM – Sofia, Bulgaria

1990 Assistant in Department of Orthodontics, FDM – Sofia, Bulgaria



Scientific activities:

Editor in chief of Orthodontic review

Member of the Editorial Board of the Journal of Dental Medicine

Member of the Editorial Board of Dental Magazine



Professional membership

BgDA – Bulgarian Dental Association

BSSDM – Bulgarian Scientific Society of Dental Medicine

BlgOS – Bulgarian Orthodontic Society (Current President)

BSLO – Bulgarian Society of Lingual Orthodontics

BAOS – Balkan Association of Orthodontic Specialists (President 2020)

EOS – European Orthodontic Society

WFO – World Federation of Orthodontists



Languages:

English

French



Research interests:

Dental arch dynamics; long-term retention after orthodontic treatment; growth and development of the dentition; physiological potential for space gain in the dental arch; myofunctional factors of occlusal stability.