Trauma of decidual teeth and the most common consequences

Dental trauma during the decidual dentition period can cause the impairment of their permanent replacements. Therefore, it is necessary to establish a diagnosis on time, to apply adequate therapy and to follow-up the patient over a period of time. Trauma of the teeth has an important place in current pedodontics, partly because of the constant increase in its prevalence. In spite of the considerable regeneratory potential of young individuals, teeth affected by trauma are more prone to exhibit various changes on their permanent replacements. Therefore, a multidisciplinary team approach is usually required in the management of this problem. Parents need to be informed about the most vulnerable period for dental trauma, and the most frequently involved circumstances of its occurrence. It would be of a great importance to develop a program of education for pre-school and school children, as well as for their teachers, which would lead to greater care during play, sport and other activities in childhood. There is no doubt that such a program would result in a considerable decrease in the incidence of dental trauma.
Keywords: DENTAL TRAUMA - complications; DECIDUAL TEETH - trauma
Dental traumas are among the leading problems in pedodontics. The number of traumatized teeth shows a constant increase, and therefore this topic continuously attracts more and more interest. According to the data gained from epidemiological studies, the prevalence of dental trauma among children in the general population amounts to 4-19% (1). These figures are significantly effected by the age and sex of the examinees, as well as of the diagnostic principles and classification used in order to evaluate dental trauma (1). However, all the investigations have yielded similar conclusions: dental trauma is more frequent in boys than in girls, and the boys are more likely to be involved in traumatic incident in general, with the ratio of approximately 1.5 : 1 with respect to the girls (1). In children of pre-school age, this ratio is somewhat smaller and it amounts to 1.2 : 1.
The child's age has a major impact on the risk of trauma, and the trauma prevalence variation with respect to age has been well-documented in both school and pre-school children through numerous studies worldwide. During decidual dentition, dental trauma represents the occurrence most likely to happen between the age of 2 and 4 years (2, 3, 4). During permanent dentition, the period with the greatest frequency of dental trauma occurs between the ages of 7 and 11 years (4, 5). In both dentitions, the most frequently traumatized teeth are the upper mesial incisors, accounting for 80% of all trauma in decidual and 85% in permanent dentition (5).
Dental trauma in traffic accidents forms 40.5% of all head trauma (6). The impact of forces on the facial skeleton most likely affects the teeth because of their prominent anatomical position.
In a study of 480 children aged 1-16 years, a total of 1024 teeth had been traumatized. The results thereby revealed that the greater the deviation from normal tooth position, the greater the possibility of trauma. In children with malocclusions, trauma of anterior upper incisors were seen in 11.7% cases, and in children with normal occlusion in only 5.8% cases, which is in concordance with findings of other authors (Figure 1).
When analyzing the same group of children according to the correlation between their age and dental trauma, it was noted that dental trauma was frequent after the first year of life. This can be explained by the fact that at that particular age a child begins to learn to walk and play, stops being confined to a bed, and therefore is at greater risk of trauma. The greatest percentage of dental trauma was recorded between the ages of 8 and 12 years. During that period, the prevalence of dental trauma of decidual teeth amounted to 24.6%, and of permanent teeth 73.4%.
The aim of this study was to investigate of some potential consequences of trauma to decidual teeth, and its further influence on the development of permanent teeth. We believe that clarification of this topic is of importance, because the long-term consequences of tooth trauma often cannot be determined or even anticipated at the very moment of trauma (7). The follow-up of the long-term consequences of decidual teeth trauma is made more difficult by the length of the period between the moment of trauma to the moment of definite diagnosis of trauma sequelae on permanent teeth.
The extensity of the long-term consequences of dental trauma is influenced by interrelation between the decidual tooth and the germ of the permanent tooth at the moment of trauma. During the period of full decidual dentition, the orofacial region is exposed to complex processess of growth and development (7, 8, 9). The parodontium of decidual teeth is much weaker because Sharpey's fibers are sparse and there is also an absence of chewing function, which is responsible for the orientation of collagen fibres and the development of the connective tissue in general. The aforementioned tissue and fibers are much thicker and more voluminous in intact teeth, while in traumatized teeth the absence of those processes compromises the protective function of parodontal ligament (8, 9, 10).
Besides that, the bone substance in small children is more spongious and elastic, and decidual teeth effected by trauma are most frequently either in the growth or in the resorption phase, and therefore they are avulsed, weakened or intruded more frequently than others (8, 10, 11, 12, 13).
In diagnostics of traumatic lesions of decidual teeth, a history of disease, clinical examination and X-ray examination are the most frequently used tools. Regarding the patient's age, data are most frequently collected from the parents through heteroanamnesis. Of the anamnestic data, the most interesting are general patient information, and information regarding the time, place, and the exact nature of trauma. Clinical examination has to include both soft and hard tissues, and the mobility of the traumatized tooth can be determined by palpation. A vitality test is not reliable at this point, because it requires the patient's co-operation, which is most frequently impossible to establish with a little child shortly after a traumatic event (1, 2, 7). X-ray examinaton enables us to develop a therapy schedule and, besides its diagnostic character, it also has a prognostic importance and therfore should always be part of standard diagnostic procedure.
In our population, the most frequent dental trauma of decidual teeth is luxation (1), which can be lateral, intrusory or extrusory. If the patient is cooperative, it is possible to perform a reposition of the traumatized tooth and fix it with a "wire-composite splint" which remains in place for 7-10 days. A careful follow-up is necessary because the development of tooth ankylosis or an inflammatory reaction is possible regardless of adequate therapy, and the consequences on the permanent tooth's germ can be irreparable. Another very frequent lesion is intrusory trauma, often followed by lesions of the soft tissue. If the deviation of the traumatized or intruded decidual tooth is smaller than one half of the clinical crown, and there is no alveolar fracture of any kind, we choose the follow-up of the natural tooth re-eruption which is most likely to occur during the following few weeks (Figure 2). Case report #1 describes a boy, 3 years of age, who hit a very low table while playing. The trauma caused the intrusion of the upper left mesial decidual incisor and smaller lacerations of the lower lip. The parent claimed that the tooth "had disappeared" during play. An X-ray was performed and complete intrusion of the upper left mesial decidual incisor was diagnosed. After six weeks, a spontaneous re-eruption occured in an atipically rotated position. Over the following 5 months, complete reposition up to a level of incisal plane had occured. The patient had a check up one year later, and the tooth was asymptomatic, but its color was more yellow and dark, with no signs of vitality. An X-ray during that examination (Figure 3) showed that, apart from a change in position, the pulp volume was significantly smaller in comparison to the other teeth. This particular change indicates the occurrence of sterile necrosis of the dental pulp as a consequence of trauma.
Case #2 describes a little girl, aged 16 months, who fell with a little bottle in her mouth and intruded the right upper central decidual incisor. After 4 weeks, a spontaneous re-eruption occured and the tooth grew to its former size within 4 months. After several months, the same girl took another blow in the area of the already traumatized frontal teeth. Besides the laceration of soft tissues, avulsion of the formerly intruded tooth occured. This resulted in a change of color of the right upper central permanent incisor to brown, with a rough surface (Figure 4).
Case #3 describes a patient aged 20 months who suffered avulsion of the left upper mesial decidual incisor, followed by growth decceleration (Figure 5). In order to prevent even more important growth decceleration of the alveolar bone, he received a temporary removable denture made at the Department of pedodontics. The denture substituted 2 decidual incisors, and the boy has taken to it well.
Case #4 describes a 7-year old boy who reported to our Department with an initial diagnosis of odontogenic tumor. The initial X-ray did not reveal the signs of calcification of the dental germs in the upper left front (Figure 6). An examination of the oral cavity revealed discontinuity in the upper left front, i.e. the absence of both decidual incisors. An X-ray showed three sharply rounded, non-calcificated masses in the upper left front. The patient's history revealed a trauma to the left upper frontal area at the age of 4, when the fractures of all three crowns occured, which after a few months resulted in necrosis of the fractured teeth’s pulp and the creation of periapical processes. The patient's mother stated that all three teeth were extracted.
After alveotomy, three masses that represented germs of permanent teeth were extracted. The involved teeth were the left upper central and lateral incisors and the left upper canine. The extracted remains did not reveal adequate calcification. The mesial incisor had its incisal margin calcified, the lateral had barely recognizable calcification in the proxymity of the incisal margin, while the canine did not reveal any calcification. Those findings are in exact concordance with the assumed development stage of the teeth at the chronological moment of trauma. After a surgical procedure to reduce the alveolar defect, a temporary removable denture was made functioning as a prosthesis for the three missing teeth. The prosthesis erradicated the esthetic deficit and speech problems.
Case #5 describes a 6-year-old girl with diagnosed trauma of the lower central permanent incisors (Figure 7). The examination showed subluxation of both lower central incisors, without sensitivity to thermal stimuli. Sensitivity was increased only during the chewing process. However, the left central incisor revealed a change in shape as well as a change in calcification, the latter being inadequate. The patient's history revealed a trauma in the same area at the age of three, including avulsion of the lower central decidual incisors. An X-ray showed damage to the lower central incisor which included abnormal tooth axis and shape. The disturbance induced increased deposition of cementum in the permanent tooth's germ, which lead to disappearance of the pulp chamber. Adequate treatment enabled a control of vitality of the damaged teeth and a cosmetic crown-shaped correcture (Table 1).
Trauma to a decidual tooth can cause the impairment of the germ of the permanent tooth, which will depend on the direction and the power of the force which caused the trauma, and also on the time interval during which the trauma occured and the reposition of the permanent tooth's germ after the traumatic event.
These assertions are confirmed by a case report where the impairment of the permanent tooth's germ caused disturbed calcification and abortion of the normal development of the permanent tooth. Further, the degree of calcification varied in each particular germ, depending on the chronologic time of the force impact, when permanent teeth germs were positioned over or behind the roots of decidual teeth.
When a tooth trauma occurs during the period of decidual dentition, it is not always possible to provide adequate therapy because of the patient’s age. Moreover certain types of trauma have to be managed with particular care. In such cases, parents should be warned about the potential consequences on permanent dentition and the need for follow-up examinations over longer period of time (7, 8, 9, 11, 14).
The consequences of decidual teeth trauma may later be manifested in several different manners, such as:
1. Retention of the permanent tooth;
Crown malformations;
Root malformations;
Hypoplastic defects (white or brown spots or true hypoplastic spots)
Hypoplastic defects manifesting as white spots will be visible on the permanent tooth if an intruded root of a decidual tooth barely touched the surface of the germ of the permanent tooth. Furthermore, brown spots are the consequences of the intrusion of the root of the decidual tooth which has caused haemorrhagia. Finally, true hypoplastic spots will result from an intrusion similar to the latter, but under much greater pressure.
It can be concluded that all the consequences of trauma during decidual dentition should be managed by a team of experts, in which the co-operation of a pedodontitian, a pediatritian and an ortodontitian is required.
Category: Clinical observations - professional paper
Volume: Vol. 42, No 3,4 july - december 1998
Authors: O. Lulić-Dukić, D. Radionov, D. Buković, Ž. Verzak, I. Bagić
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