Premature Loss of Primary Incisors

in one sentence:

We do not recommend space maintenance for premature loss of primary incisors.

Of all primary teeth which may be lost prematurely, the incisors seem to be least likely to result in significant space loss, dimensional changes, or negatively affect the developing occlusion (46,50,51). Borum and Andreasen, in a study of 287 children who experienced trauma to the maxillary primary incisors, found that only 1.8% of children who prematurely lost one or more teeth experienced space loss in the anterior region (52).

The lack of space loss is especially true following the eruption of the primary canines, which help to stabilize arch dimensions. Furthermore, if a maxillary incisor is lost, the mandibular occlusion tends to hold the maxillary intercanine width constant (30,40,51). Thus, space maintenance is not indicated to preserve arch integrity following premature loss of primary incisors.

While space maintenance is not indicated to preserve arch dimension, you may wonder about functional and aesthetic considerations when anterior teeth are lost.

What does the literature say?

  • One consequence of premature loss of a maxillary primary incisor is delayed eruption of the permanent successor due to formation of reparative bone and dense connective tissue in the path of eruption (Figure 1) (40,53). This can cause a delay in eruption of the permanent incisor by an average of 16 months, 53 and may require management with a gingivectomy to facilitate eruption (54). The position of the permanent successor, when it does erupt into the mouth, may also be affected due to the early extraction or traumatic incident. This is attributed to a lack of guidance by the primary tooth root or deflection of the developing tooth bud during trauma (55). Space maintenance does not provide a solution to these issues.

  • Aesthetics may be of psychosocial concern to some families when primary incisors are lost. In such cases, a missing anterior tooth or teeth can be replaced by fixed or removable appliances with built-in prosthetic teeth (20). Examples of appliances which meet such aesthetics demands are the Groper’s appliance (56,57) (Figure 2) or a “Hollywood” bridge (40,58) (Figure 3). The main difference between the two is that the Groper’s appliance consists of acrylic teeth attached to metal clefts which are soldered onto a palatal wire whereas the Hollywood bridge uses acrylic teeth and a buccal acrylic flange (59).

  • Loss of primary anterior teeth may also affect pronunciation and phonation in children (51). Despite this, due to reasons of compliance, appliance damage or loss, and practicality, space maintenance that includes pontic teeth is generally not indicated (53). Moreover, there is a lack of evidence for the benefits of SMs in this scenario, and any speech impairments are usually transient, disappearing when the permanent incisors erupt (53). Speech therapy can also be considered as an alternative solution if need be (51).

Figure 1. Delayed eruption of the permanent maxillary central incisor in a 7-year-old due to premature traumatic loss of all four primary incisors and the right C. Adapted from Holan and Needleman, 2014 (53).

Figure 2. Maxillary arch with Groper’s appliance replacing teeth 5.2, 5.1, and 6.1. Adapted from Joybell et al., 2015 (57).

Figure 3. A Hollywood bridge replacing teeth 5.2, 5.1, and 6.1. Adapted from Chalakkal et al., 2013 (58).

Click to see the references.

Clinical Pearls from Dr. Jeff

What about the scenarios that are less clear cut or you’re on the fence: Should you always save the incisor(s) if you can? Is a space maintainer ever indicated? Is there a difference between managing caries vs trauma? Here are some helpful tips from Dr. Jeff based on his years of clinical experience.

GENERAL

Losing primary (maxillary) incisors occurs frequently - the most common causes are related to pulpal pathology resulting from early childhood caries and traumatic events. Luckily, the impact is relatively minimal.

Very early loss of incisors

The loss of a primary incisor prior to the eruption of the primary canines is much more likely to have an impact on the alignment of the maxillary anterior teeth and is more frequently associated with a disturbance in speech. Even if one wanted to consider an appliance, cooperation and a lack of abutments is typically prohibitive.

Concerns about function

Fortunately, most children adapt quickly to the loss of one, two, or even four incisors quite quickly. The impact on speech, especially after the age of 2 years or so, is often transient in nature.

Managing Caries

If caries are present, small asymptomatic lesions do not necessarily have to be treated. As the size of the lesions progress, there is a greater chance of symptoms. Monitoring the teeth, applying fluoride, applying SDF to "buy time", or treatment (including pulp therapy and the placement of a suitable restoration), are all reasonable options that might delay and perhaps avoid the need to extract primary incisors. The longer they remain in place, the less likely there will be a loss of space if teeth have to be removed.

Managing TRAUMA

The impact of losing a tooth due to trauma is effectively the same as losing a tooth as a result of caries (that has progressed to be associated with symptoms of pain and/or infection). In both situations, monitoring the teeth over time - as per trauma guidelines - is essential. The presence of apical pathology can lead to disturbances in the development of the permanent successor; discolouration of a tooth does not in itself justify treatment, but it is certainly indicative of a potential problem and necessitates monitoring the tooth both clinically and radiographically. If, over time, a tooth that has experienced trauma becomes symptomatic (pain, mobility, abscess / infection), then its removal is indicated. The implications from a space maintenance point-of-view are the same as those associated with the caries.

Actual vs apparent space loss

Even after a single tooth is lost, sometimes there is a rearrangement of space and not an actual loss of space; if one uses the canies as a reference, their position is often unchanged.

FINAL THOUGHTS

Attempting to hang on to a primary incisor for as long as possible - certainly beyond the time it takes for the canines to fully erupt - is a most reasonable goal. After the canines have erupted and once a child has reached the age of four, the loss of a primary incisor has virtually no impact on the developing dentition. Function (eating, and speech) are rarely affected and so, once again - the concerns may be more about esthetics. Replacing teeth for this reason alone will obviously improve the esthetics and will typically function as an adequate space maintainer but the later rationale is hard to justify on its own.