Association of Crown Discolouration and Pulpal Status of Traumatised Primary Tooth in 3 to 8 year old children - A Retrospective Study

Keywords

Crown Discolouration; Primary Teeth; Pulpal Status; Trauma.

Introduction

Out of the many assets an individual possesses, having a ‘smile’ with beautiful and natural teeth is one of the greatest assets. It continues to be the most common infectious disease in children [15]. If a fractured anterior tooth with an unsightly fracture is left untreated, it can affect the behaviour of the child, his progress in school, which will indirectly cause more impact in their daily living. Functionally, primary teeth is also considered to be a natural space maintainer as it serves as a guide for the eruption of permanent teeth to its proper position in the dental arch [2]. Thus, apart from dental caries or periodontal disease, tooth loss that is caused by trauma, which happens as a result of either violence, accidents, falls or even sport-related activities becomes a main concern especially to young children [15].

Traumatic dental injuries (TDI) is defined as a dental injury to the tooth, periodontium as well as soft tissues. Even though dental caries continues to be the most common disease affecting children, [7] we should not forget that TDIs is also said to be one of the most prevalent oral pathologies in both children and adolescents [21]. An estimation of 22.7% of children ranging from 0 to 6 years have TDI during their early childhood involving the primary dentition [21]. While almost 25% of all school children and adolescents ranging from 7 to 19 years have a TDI involving their permanent dentition [6, 1].

A majority of the dental injuries involve anterior teeth [16]. Epidemiological studies indicate that in the near future, dental trauma could be a prominent problem especially in young people such that it will surpass both dental caries and periodontal disease [18]. Traumatic dental injuries are seen to be a serious dental public health problem among children in deprived areas [15]. The incidence of these types of injuries especially to the primary dentition presents as a challenge for the dentist, as it could not only create panic to the parents but could also instil anxiety and fear in the child [23]. This issue should be highlighted as parents and responsible adults are the principal people in a child's development in the early years, [11] as it could potentially greatly impact the quality of life for young children [25].

Based on previous studies that were done, the occurrence of dental tissue trauma (either enamel or dentin fracture) will be prone to bacterial invasion in the fracture causing further infection and exposed dentinal tubules can ultimately lead to pulpal inflammation resulting in either repair or necrosis of the pulpal tissues [1]. Not to mention that the discolouration of the tooth post trauma can negatively impact the Oral Health Quality of Life (OHRQoL) of both children and adolescents [22, 26].

As the result of the fluoridation of community water supplies in India, which is considered as an effective way in dental caries prevention and its progression, (‘Fluoride, Fluoridated Toothpaste Efficacy And Its Safety In Children - Review’, 2018) this different form of crown discolouration caused by fluoride is also common in children [24]. However, unlike the discolouration caused by fluorosis, the one that is caused by TDIs have not shown an exact correlation especially when the pulpal tissues are involved. Nonetheless, crown discolouration is still one of the most common complications related to TDIs. It is the result of external expression which represents the changes occurring in the pulp dentin complex, making it visible through a translucent enamel. Though some might say it is a sign of internal damage, it is not necessarily an irreparable damage [4].

In this study, the aim is to analyse the association between pulp necrosis and crown discolouration in a traumatised primary teeth. The main purpose being that more insight can be provided in the data correlation between the pulpal status and crown discolouration. With this a better diagnosis and treatment planning can be provided followed by a better prognosis.

Materials and Methods

Out of the 1269 patient records available from the institution, 12 patients in the age group of 3-8 years had a history of trauma in relation to their primary teeth. A record of each patient’s age, gender, tooth number, presence of crown discolouration, pulpal status of tooth, treatment done, length of the root and the presence of soft tissue swelling was obtained through patient records and the data of 86000 patients, which included data from June 2019 to March 2020.

All available data was included and cross verified with both the preoperative photographs and radiographs. By doing so, it has prevented the presence of bias during the case selection process.

The data was analysed with IBM SPSS Statistical Analyser (23.0 Version). The frequency distribution and the Chi-square tests were done. The correlation between the presence of soft tissue swelling was completed through Pearson Chi-square test and likelihood ratio.

Results

In regard to the gender distribution of the sample size, 10 (83.3%) of the paediatric patients are males while the remaining 2 (16.7%) of them are females. [Graph 1]

Pulpal Status and The Presence of Crown Discolouration

Based on the pulpal status, in cases of asymptomatic irreversible pulpitis, about 4 (66.7%) patients had evidence of crown discolouration while the remaining 2 (33.3%) patients had no evidence of discolouration.

Similar to the findings in asymptomatic cases, in terms symptomatic irreversible pulpitis, 4 (66.7%) patients presented with crown discolouration clinically while the other 2 (33.3%) patients presented with no discolouration. [Graph 2]

When the chi-square test was done, there was no statistical significance between the pulpal status and the presence of crown discolouration (p=1.00).

The Root Length and Treatment Done

In cases where extractions were done, the highest cases where done when the remaining root length was 6mm (25.0%) while the lowest cases were when the root length was 10mm, 8mm and 7mm (8.3%).

In regard to pulpectomy procedures, it was most commonly done when the root length was 11mm (16.7%) while the least commonly done was in both 10mm and 9m (8.3%). [Graph 3]

Once analysed through the chi-square test, it showed statistical significance between the root length and the treatment done (p=0.05).

Pulpal Status and Presence of Soft Tissue Swelling

When diagnosed with asymptomatic irreversible pulpitis, 5 (41.7%) patients showed no evidence of soft tissue swelling in regards to the traumatised primary tooth with only 1 (8.3%) patient showed evidence in soft tissue swelling.

Similar to that with symptomatic irreversible pulpitis cases, a majority of 4 (33.3%) patients had no evidence of soft tissue swelling while the remaining 2 (16.7%) patients showed presence of soft tissue in relation to the traumatised primary tooth. [Graph 4] When chi-square tests were done, it showed that there was no statistical significance between the pulpal status and the presence of soft tissue swelling (p=0.50).

Crown Discolouration and Presence of Soft Tissue Swelling

In the presence of crown discolouration, it was found that only 3 (25.0%) cases showed evidence of soft tissue swelling as well while the remaining 5 (41.7%) patients had no such findings. When no presence of crown discolouration was found, all 4 (33.3%) cases also had no evidence of soft tissue swelling. [Graph 5]

Once analysed through the chi-square test, it was found that there was no statistical significance between the crown discolouration and prevalence of soft tissue swelling (p=0.25).

Based on this study, males showed a higher prevalence in crown discolouration for a traumatised tooth compared to females. Similar to a study done by Cardoso M et al, it also stated the higher rate of crown discolouration in males. However, based on our study such findings could not be truly justified because of the limited sample size [2].

In regard to the pulpal status of the traumatised primary tooth, it was found that crown discolouration was equally common in both asymptomatic and symptomatic irreversible pulpitis. Contradicting our study, Cardoso M et al found that a higher association was found between crown discolouration in pulpal necrosis of traumatised primary teeth. The reason behind this is because the timing in which the patient reported to the clinic was prolonged, that resulted in the advancement of pulpal necrosis [2].

Based on the root length, it was found that extractions were commonly done for shorter root lengths while pulpectomy was opted in longer root lengths. When dealing with a necrotic primary tooth, early loss of tooth is a main concern in paediatric dentistry. Ideally, pulpectomy should be the treatment option with the sole intent of maintaining the integrity of the facial tissue [9]. However, even though pulpectomy is considered to be the treatment of choice when pulp is involved in the primary teeth, the main reason the root length plays an important role is because there would not be a sufficient radicular structure for pulpectomy to take place [13]. In future studies related to this topic in hand, the use of rotary instruments should also be included since endodontics is a field that is constantly undergoing evolution [10]. According to a study done by Jeevanandan et al, the usage of rotary instruments in primary teeth not only reduces the instrumentation time, it also provides a better quality obturation [14]. Though conventional hand file system is known as the gold standard in the field of paediatric endodontics [17], further research on this matter would surely lead to the formation of a faster and safer protocol for endodontic treatment in primary teeth [8].

In the presence of crown discolouration, we found that it is more commonly associated without the presence of soft tissue swelling. Holen G et al found from their studies that discolouration of the crown is normally associated with the non-vital tooth and rarely the supporting structures [12].

When there is evidence of soft tissue swelling, both the asymptomatic and symptomatic irreversible pulpitis showed no association with it. A study done by Yu CY et al with similar findings explained that when there is minor displacement in the gingival integrity , the marginal periodontium can be re-established due to its ability for regeneration [27].

Throughout our study, there were some limitations that were encountered including a limited sample size with limited follow up [3] which may in the future lead to unevaluated side effects [19]. At the same time, the duration of study was also short.

In future studies, to provide an even thorough and significant result, a larger sample size should be obtained and a longer duration of study should be implemented.

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Conclusion

Within the limits of our study, we found that crown discolouration due to trauma in primary teeth is prominent in both asymptomatic and symptomatic irreversible pulpitis. However, teeth with longer root lengths will commonly undergo pulpectomy procedures while teeth with shorter root lengths commonly undergo extraction procedures.