Research and EducationMaxillary lateral incisor agenesis and its relationship to overall tooth size
Section snippets
Material and Methods
This research was approved by the Institutional Review Board. Forty sets of dental casts (21 women, 19 men, mean 15.9 years of age), with missing maxillary lateral incisors (22 unilateral, 18 bilateral) (Fig. 1), were collected from local orthodontic practices. For comparison, an equal number of dental casts were collected from the Graduate Orthodontics program at the Marquette University School of Dentistry to form a control group matched for ethnicity, age, and sex. Inclusion criteria for the
Results
The results of this study reject the null hypothesis that no differences exist in tooth size in patients with agenesis. Orthodontic patients with agenesis of one or both maxillary lateral incisors exhibited smaller than normal tooth size than the control group. (F=4.01, P=.049) (Table 2; Fig. 3A).
Men were found to have larger teeth than women. (Table 2; Fig. 3B). Canine teeth presented the largest tooth size differences between men and women (there was a significant tooth type×sex interaction
Discussion
Although clinicians discuss the minimum necessary space for an implant when one or both maxillary lateral incisors are missing, they should focus on determining the appropriate space for the implant/restoration. The golden proportion for the anterior teeth can be considered when they determine the size for the missing lateral incisor.3 Patients with smaller than normal maxillary and mandibular teeth, as shown in the test sample of this study, may require a smaller than necessary 6.5-mm or 7-mm
Conclusions
Orthodontic patients with unilateral or bilateral agenesis of the maxillary lateral incisor have smaller than average teeth when compared with a control-matched group. The maxillary arch has larger tooth size differences between the control and test groups than the mandibular arch. Clinicians should consider the findings of this study when preparing maxillary lateral incisor sites for restorations.
Acknowledgments
The authors thank Drs William Lobb, Gerard T. Bradley, and Dawei Liu, Marquette University School of Dentistry, for advice and suggestions; and Jessica Pruszynski and Dr Raphael Benoliel for statistical analysis.
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Cited by (13)
Three-dimensional digital evaluation of tooth symmetry and volume in patients with missing and peg-shaped maxillary lateral incisors
2022, American Journal of Orthodontics and Dentofacial OrthopedicsCitation Excerpt :In contrast, Coskuner et al16 detected a significant difference in the posterior part of the dentition in their study group comprising unilateral maxillary lateral incisor agenesis. The pendulum swings between these 2 types of views, which might suggest that Wright et al’s13 perspective that no specific tooth group could be held accountable for this discrepancy is valid. The researchers documented significantly diminished overall tooth sizes in patients with unilateral and bilateral missing lateral incisors without being able to identify any specific tooth group.
Missing teeth in the smile area: space closure in all malocclusions looking for long term health, esthetics and function
2020, Seminars in OrthodonticsCitation Excerpt :Restorative enlargement of the intruded first premolar is almost always necessary, as well a minor reconstruction of the incisal edge of the ground canine substituting the lateral incisor. Restoration of the central incisors are mandatory not only when the lateral substitutes a missing central incisor, but also in patients with CMLIs, because their entire maxillary dentition is undersized.12-15 Do extractions necessarily result in a flat face and narrow smiles?
Maxillary incisor root morphology in patients with nonsyndromic tooth agenesis: A controlled cross-sectional pilot study
2020, American Journal of Orthodontics and Dentofacial OrthopedicsNew perspective for evaluation of tooth widths in patients with missing or peg-shaped maxillary lateral incisors: Quadrant analysis
2018, American Journal of Orthodontics and Dentofacial OrthopedicsCitation Excerpt :Therefore, our first and third hypotheses were partially accepted, and the second hypothesis was fully accepted. Few authors have evaluated the relationship between the congenital defects of maxillary lateral incisors (agenesis or size discrepancy) and the mesiodistal widths of other teeth.18-20,27,28 However, these studies had some limitations that may prevent clinicians from drawing conclusions about certain clinical situations.
The restorative dentist and orthodontist: Orthodontic implications of dental caries, tooth fracture, exposed dental pulp, and esthetic improvements
2023, Integrated Clinical OrthodonticsOrthodontic treatment before restoration of dentition defects
2023, Chinese Journal of Stomatology
Supported, in part, by the American Association of Orthodontists and American Association of Orthodontists Foundation (to J.A.B.).