INTRODUCTION
The smile is one of the most important components of perception and
self-perception of people. It directly influences the facial expression
and physical attractiveness of individuals (1). In contemporary dental
practice, patient-driven esthetic diagnosis and treatment planning force
clinicians to focus on the smile zone, which is directly from the
patient’s perspective(2). Improper anterior spacing can cause diastemas
and thus it could be considered as unesthetic by lay people (3,4). It
can be caused by microdontia, a genetic condition in which the teeth are
abnormally small. This anomaly can be localized or generalized. One of
the most common forms of localized microdontia is that which affects the
maxillary lateral incisors, called a “peg lateral”. A peg-shaped
incisor has a marked reduction in diameter, extending from the cervical
region to the incisal edge (5).
The prevalence of peg-shaped upper lateral incisors was reported to be
higher than the prevalence of other morphological variations of
permanent teeth. Agenesis or size or shape anomalies of maxillary
lateral incisors are quite common, with a prevalence of 1,6% to 4,9%
and can be either unilaterally or bilaterally on the left or right side
of the jaw with a higher incidence on the left side of the incisors (6).
Yet, women have 1.35 more chance of having peg-shaped maxillary
permanent lateral incisors when compared to men. Simultaneous presence
of both upper lateral incisors is a rare case (7).
Treatment choices for lateral peg-shaped incisors are various, however
for any esthetic rehabilitation, it is necessary to follow a medical
framework respecting the tissue economy and combining the biological,
functional, and esthetic imperatives which are inseparable.
Treatment options for peg shaped laterals could be: no treatment,
orthodontic treatment first (to align the teeth in the arch), direct
composite bonding onto peg laterals, indirect composite placement,
bonded crowns or veneers, or even metal crowns (8), extractions and
implant placement, or a combination of treatments.
Orthodontics is the first esthetic therapy in the gradient and the most
conservative. Most of the time the patient presents a maxillary default
: a dento-dental disharmony resulting in an anterior Bolton index
greater than 77.2% +/- 0.22 (9). An ill-considered closure of the
spaces would lead to anterior buttock. In addition to the esthetic
appearance of the reconstructed laterals, the lateral teeth are then
overhung, and a functional anterior guide is ensured after prior
placement of the canines in Angle Class I. Several therapeutic solutions
can be envisaged depending on the associated anomalies: extractions,
closing of spaces with the consequences associated with dento-dental
disharmony, or morphological rehabilitation of these teeth to ensure the
establishment of ideal inter-archal relationships.
In this case, the definitive mesio-distal diameter and final vertical
positioning of these teeth must be determined at the beginning of the
ODF treatment. In order to facilitate active orthodontic treatment (both
for the bonding of an attachment to this tooth and for its future
pre-prosthetic design), the peg-shaped lateral incisor should be
provisionally reconstructed according to the described esthetic criteria
(shape, mesio-distal diameter, color in relation to the adjacent teeth)
prior to the placement of any appliances. This provisional restoration
can be improved and readjusted during orthodontic treatment. However,
the intra- and/or inter-arch clinical situation does not always allow it
in case of maxillary anterior crowding with overlaps, dental rotation,
linguo-version of the incisal block reducing the arch perimeter and
consequently the spaces devoted to the lateral riziform incisor. The
orthodontic treatment will, under these conditions, have to start
aligning and levelling the maxillary arch, in particular, in order to
meet the above-mentioned requirement.
The lack of clear best practices in the scientific literature encouraged
us to establish a protocol to facilitate the therapeutic decision with
the general practitioner, the orthodontist and the patient, and
ultimately to guarantee the therapeutic solution best suited to the
clinical situation. The patient is often referred to the general
practitioner once the orthodontic treatment has been completed. This
lack of coordination between disciplines represents a real loss of
opportunity for patients. In this article we aim to clearly establish
the different considerations to be evaluated and the steps to follow,
once orthodontic treatment is started, to ensure best possible
rehabilitation for the patient.