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 Table of Contents  
Year : 2019  |  Volume : 9  |  Issue : 3  |  Page : 258-263

Choice of material for the treatment of proximal lesions in deciduous molars among paediatric post-graduates and paediatric dentists of Gujarat: A cross-sectional study

Department of Pedodontics and Preventive Dentistry, Karnavati School of Dentistry, Gandhinagar, Gujarat, India

Date of Web Publication6-Sep-2019

Correspondence Address:
Srushti M Khurana
B.403, Shukan Villas, Near Sargasan Chowk, Sargasan, Gandhinagar - 382 421, Gujarat
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/AIHB.AIHB_67_19

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Introduction: Restoring Class II lesions in deciduous molars has always been a nightmare for the dentist. This survey was designed to understand the perception of dentists regarding the treatment choice. Aim: The aim of this study is to determine the choice of material and influencing factors for the treatment of proximal lesions in primary molars. Materials and Methods: The cross-sectional web-based survey enclosing nine closed-ended questions was conducted among 180 paediatric dentists and post-graduates of Gujarat. Data were obtained and evaluated at the statistical significance level ofP < 0.05. Results: For 65% of respondents' stainless steel crowns (SSCs) was preferred material for the treatment of cavitated Class II lesions followed by composite and for non-cavitated incipient proximal lesions silver diamine fluoride was preferred by 71% of respondents. Childs age and child's behaviour were the most influencing factors affecting the choice of material (P < 0.001). Conclusion: Different clinical situation requires a different choice of material. The present study enlightens current perception and preference regarding the material of choice in a different situation while restoring Class II lesions in primary molars. We concluded that SSC was the most suitable material of choice amongst a wide range of materials by paediatric. The older concept 'excavation for prevention' is still applied as compared to newer minimal invasive strategies. Many factors contribute to the treatment and material choice for restoring Class II lesions; thus, one ultimate material cannot be selected for all kinds of situations. Thus, it highlights the current trends followed among paediatric dentist.

Keywords: Class II lesions, primary molars, proximal caries, stainless steel crown

How to cite this article:
Patel MC, Bhatt RK, Khurana SM, Patel NG, Bhatt RA. Choice of material for the treatment of proximal lesions in deciduous molars among paediatric post-graduates and paediatric dentists of Gujarat: A cross-sectional study. Adv Hum Biol 2019;9:258-63

How to cite this URL:
Patel MC, Bhatt RK, Khurana SM, Patel NG, Bhatt RA. Choice of material for the treatment of proximal lesions in deciduous molars among paediatric post-graduates and paediatric dentists of Gujarat: A cross-sectional study. Adv Hum Biol [serial online] 2019 [cited 2022 Jun 25];9:258-63. Available from: https://www.aihbonline.com/text.asp?2019/9/3/258/266228

  Introduction Top

Dental caries is the most prevalent disease of childhood. This disease eventually leads to pain and tooth structure defects. Dental caries can be observed in developing and developed countries. This disease begins to develop at a very early age and if not treated, can cause various consequences, including damage to present and erupting teeth. The undesirable effects of early childhood caries can lead to malnourishment, insomnia, negative behavioural patterns, unaesthetic appearance and deformities in speech. This eventually leads to social and economic issues faced by the family.

In 2018, a study by Ganesh et al.[1] concluded that 49.6% was the prevalence rate of early childhood caries in India, whereas the maximum was seen in Andhra Pradesh (63%) and minimum seen in Sikkim (41.92%). None of the states had prevalence <40%. In the survey conducted in 2011, 158.79 million children were present in the age group of 0–6 years.[2] Among the 79.4 million are suffering from early childhood caries in India. Males (4–6 years) were more prone to dental decay as compared to that of females. Primary molars amongst all are subjected more to the incidence of caries owing to its occlusal anatomy due to which food tends to accumulate more in pit and fissures. In children, dental caries usually involves pulp due to an increased pulp: Crown ratio. In permanent teeth pulp: Crown ratio is higher, which leads to delayed pulpal involvement. The marginal ridge breakdown in primary teeth usually shows pulpal changes histopathologically.

Amongst the various options available for restorative material, appropriate one should be chosen for primary teeth. Class II caries in deciduous molars is important to treat as they serve as Natural space maintainer, helps in proper mastication and prevents arch length discrepancy. Furthermore, the primary molars with Class II lesions are most difficult to restore as they have; (a) Broad contact area, (b) High pulp horns – as a result shallow cavity, (c) difficulty matrix band placement, (d) less retentive cavity due to less enamel dentine thickness – increase secondary caries and (e) child co-operation for the treatment. Hence, restoring a Class II lesion in children becomes a challenging task.

Various advances and innovations are available for restorative dental material for paediatric patients. Over 120 years Amalgam was used as gold standard material for restorations in dentistry. Along with amalgam, other restoration materials available are composite resins, resin-modified glass ionomer cement (RMGIC), improved GIC and stainless steel crowns (SSCs).

Recently, dentists are choosing aesthetic, and tooth coloured restorations more as compared to amalgam. Till date, no proper guidelines are available for clinician preference for correct material selection in various clinical situations in the literature for paediatric dentistry.

Advances and modifications in dental material cause the material selection task for dentists a challenge. Hence, this study was conducted to determine the choice of restoration and influencing factors for the treatment of Class II lesions in primary molars among paedodontic post-graduates and paediatric dentists of Gujarat.

  Materials and Methods Top

A cross-sectional study was conducted amongst the paedodontic post-graduates and paediatric dentists of Gujarat. A web-based (SURVEY MONKEY) self-administered survey was circulated among 180 paedodontists of Gujarat. Sample size for this study was determined at 85% confidence interval for P that is expected to be about 50% (0.50) with a margin of error (d) no more than 0.098, n = (1.96^ 2) (0.50) (1 − 0.50)/(0.098^ 2). n = 125. The questionnaire contained close-ended nine questions with the multiple-choice format. A questionnaire was used for collecting data which consists of the following parts:

  • Demographic information including years of experience
  • Questions for the most preferred material of choice for the different clinical situation in the treatment of proximal lesions in primary molars
  • Type of preferred technique for the treatment of Class II lesions in primary molars
  • Most influencing factors for the treatment of Class II lesions in primary molars.

Data were analysed using the Chi-square test, and Fisher's exact test with P < 0.05 as the significant value was applied to find out the significance of various responses. All the data were entered and analysed using the SPSS (V.18 for Windows, IL, USA). Descriptive statistics and tables were generated separately.

  Results Top

An online survey enclosing nine questions was circulated through survey monkey to 180 Paedodontic of Gujarat. One hundred and twenty of the total respondents completed the questionnaire with a response rate of 85%. Paediatric post-graduates more actively participated in the survey, with 80% respondents compared to 20% responses by a paediatric dentist. All respondents were asked about clinical experience in paediatric dentistry. The survey reflected that maximum number 70% of respondents had 0–5 years of experience.

Choice of treatment for cavitated class II caries

SSC was most preferred making (65%) for cavitated lesions. Composite is the 2nd most used (11%) followed by GIC. It was seen that zirconia crowns were less preferred for the treatment of cavitated Class II lesions (P < 0.001) as shown in [Graph 1].

Choice of material for the treatment of non-cavitated incipient proximal lesions

Recently popularised silver diamine fluoride (SDF) was the most preferred material for non-cavitated proximal lesions (71%) as seen in [Graph 2]. Composite and GIC were the second most preferred material making 11% and 10% each. RMGIC (4%) and SSC (4%) very less preferred by paediatric dentists for non-cavitated proximal lesions (P < 0.001).

Long-term success of restorative material for Class II lesions

In [Graph 3] it can be seen that SSCs showed maximum success 75% by respondents for Class II lesions. Composite (10%) too was preferred by respondents. GIC and RMGIC were less considered 4% and 6%, respectively, by paediatric dentists where long-term success of restorative material is required (P < 0.001).

Preference of liners in proximal lesion approaching pulp

Light-cured calcium hydroxide (75%) was the most used liners. GIC, and RMGIC were not much preferred as liners (P < 0.001) as depicted in [Graph 4].

Treatment procedure in class II lesions with no pulpal involvement

According to the [Graph 5] in cases with no pulpal involvement with Class II lesion paedodontists preferred excavation and then restoration protocol (75%) more as compared to restoration without excavation procedure (25%) (P < 0.001).

Preference for hall technique

In the [Graph 6] fourteen percent of respondents preferred hall technique while restoring Class II lesions. 28% of respondents sometimes preferred hall technique. 40% of them never used hall technique and 18% of them had no idea about hall technique for restoring proximal lesions (P < 0.001).

Factors influencing materials of choice

Respondents were asked to rank the influencing factors to determine the material choice. It was seen that child's age influenced the most while making a choice. Childs behaviour was another factor which ranked second most influencing, followed by moisture control. The least influencing factors were affordability by patients. Strong evidence-based and aesthetics were also not considered an influencing factor for material choice amongst responding to paediatric dentists as seen in [Table 1].
Table 1: Factors affecting material of choice

Click here to view

  Discussion Top

A cross-sectional survey was used to investigate restorative material choices preferred by paediatric dentists in a variety of scenarios involving primary posterior teeth. The specific scenarios were not represented with radiographs or clinical photos to minimise interpretation discrepancies.

Kilpatrick[3] conducted a comprehensive review of the durability of restorations on primary molars. He concluded short lifespan of primary teeth, variation in morphology of primary teeth, age and patient compliance affects the choice of restorative material in the primary dentition.[3],[4]

A current shift of trend from the amalgam to tooth-coloured materials is widely seen in several studies.[5],[6],[7] On comparison of the three surveys, preference of tooth coloured restoration over amalgam increased with time and was geographically related.

According to survey conducted by Buerkle et al.[8] in 2005 stated that the use of amalgam was demolished as restorative material of choice in European dental schools of north Europe, but amalgam was used still used in the south (23.1%), west (33.3%) and east Europe (35%), respectively.

A survey by Tran and Messer[6] 2003 suggested that the amalgam was used exclusively by only 2% members of the Australasian Academy of Paediatric Dentistry, 3% of the members of the New Zealand Society of Paediatric Dentistry when compared to 89% that mainly preferred tooth-coloured materials. It has been reported that the success rate of teeth treated with SSC was higher than that restored with amalgam or modified open sandwich restoration.[9],[10] Also it is evident that preformed metal crown restoration has greater longevity to amalgam or resin based cement for carious lesion treatment in deciduous teeth.[11]

In the present study, a SSC was the most preferred material of choice for cavitated proximal lesions. SSC may have been chosen because it is easier to place the restoration, especially if the patients' behaviour is difficult, caries risk is high or if the tooth required a pulpotomy or had circumferential carries.[12]

SSCs higher acceptance over Class II lesions in grossly carious lesions in deciduous molars can be due to its unique morphology. The broad interproximal contacts and slender buccolingual dimensions in primary molars usually lead to overextension proximal cavities in large carious lesions. This causes unsupported enamel at the buccal and lingual margins, which under occlusion or mastication, leads to open margins which lead to defective marginal seal, recurrent caries and hence, restoration failure increases. Amongst all restorative material available SSC has shown better durability and longevity.[12] SSCs are material of choice for primary molars with proximal lesions, grossly carious teeth, Class V lesion and pulp therapy treated deciduous teeth.[12],[13],[14] SSCs are also indicated for high caries risk patients and patients with enamel dentin defects.[12]

Atieh conducted a 2-year randomised control trial regarding restoration of deciduous teeth that had undergone a pulpotomy treatment. A non-significant difference in survival rate for teeth treated with preformed metal crowns (95%) as compared to RMGIC restoration (92.5%).[9] In a similar prospective study, a comparison of restoration failure was compared in calcium hydroxide treated pulpotomy. It was seen that preformed metal crowns (79.7%) had less restoration failure as compared to amalgam (60%) after 1-year follow-up.[10]

Composites constitute of the resin matrix and silanised glass. Composite imparts better aesthetics with minimal cavity preparation. It possesses high wear resistance and helps to strengthen residual tooth structure. The evaluation of the success rate of posterior composite resin in the primary dentition has shown lower success rates mainly due to micro-leakage, bond failure and recurrent caries.[3] It was seen that the other most used material was composite. However, due to technique sensitive and requirement of good moisture control, it was the less preferred material for a cavitated lesion in children whose behaviour is often a major shortcoming.

GIC were the most preferred restorative material over many decades. Various newer developments and modification were introduced over a period of time. Various variants of GIC include conventional GIC, RMGIC and compomers. The fluoride-releasing property and chemical bond formation to tooth structure were the two main properties of conventional GIC. GICs are not suitable for load-bearing areas due to its low tensile strength and wear resistance properties.[15]

RMGICs were introduced to surpass the problems caused by conventional GICs failures. RMGIC possesses the basic property of GIC as well as the addition of 2-hydroxyethyl methacrylate (HEMA) or Bis-GMA as a resin component. This has led to increased working time and better handling properties. The wear resistance and physical strength of cement have improved too.[16],[17] The RMGIC can be used for initial Class II lesions, as an alternative to SSC.

In the conducted study, it was seen that majority of the respondents preferred SDF as a treatment modality in case of non-cavitated Class II lesions.

SDF has an anticaries property which arrests the dental decay and prevents the spread of dental decay in younger children.[18] The widespread usage of SDF is due to its preventive and therapeutic property, which temporarily halts the spread of caries. Hence it can serve as an interim procedure until the child reaches a more cooperative stage. It is mainly used as a non-invasive alternative treatment for dental decay.[19] In the study by Clemens et al.[20] showed that SDF was effective on carious lesions that were initial (ICDAS 1 or 2), non-cavitated (ICDAS 3 or 4), and cavitated (ICDAS 5 or 6). In the conducted study, it was seen that majority of the respondents were post-graduates and preferred SDF as a treatment modality in case of non-cavitated Class II lesions. Post-graduates at the college level are still learning the behaviour management techniques and are curious to try out new products.[21] Due to its ease of use with better efficiency, SDF was more preferred by post-graduates according to study.

In a study by Chu et al.,[22] SDF applications prevented the spread of lesion by 38 percentages as compared to fluoride application. In another study, SDF acted as an effective agent in arresting caries in Nepalese children aged 3–9 years; at 1 year follow-up. He stated a mean of 4.2 arrested tooth surfaces were seen per child after a single application of SDF as compared with 1.2 arrested surfaces for controls.[23] Dos Santos et al.[24] found that SDF was more promising for arresting decay in primary teeth than interim restorative treatment. It can be stated that SDF is easy to use with high efficiency and well-accepted non-invasive modality for non-cavitated lesions thus most preferred by paedodontists of Gujarat.

About 14% of the respondents in the present study preferred adapting hall technique. Dr. Norna Hall, from Scotland, had introduced hall technique and practised this technique for over 15 years until 2006 when she retired. The absence of Local Anaesthesia and the rotary devices makes this technique very child-friendly. It is time-saving and reduces chairside time. Thus reducing the child's anxiety and improving their compliance. Hall's technique is commonly used for the treatment of proximal lesions where there is extensive demineralisation (Innes et al. 2006, 2007).[25],[26] Conducted a clinical trial in Scotland to compare Hall's crown with the conventional restorative technique. The study showed that 92% of the teeth with the Hall Technique were more successful as compared to 52% of the teeth with conventional restoration.

The cavity liners are used due to its potential to reduce viable microorganism, it also causes remineralisation of carious tissues and induces the formation of reactionary dentine formation. It helps to maintain the integrity of vital pulp. It was seen that 75% of respondents used light curing calcium hydroxide as a liner in proximal lesions approaching pulp. Calcium hydroxide, due to its antibacterial effect has been used since ages for cavity lining of the cavity floor which are in proximity to the pulp. The antibacterial properties of calcium hydroxide are derived from its dissociation into calcium and hydroxyl ions, respectively. The hydroxyl ions produce alkaline pH that is unfavourable for remaining bacteria in the cavity. Hydroxyl ions are highly oxidant free radicals that show increased reactivity.

In the last question, respondents were asked to rank the factors according to which they decided the material of choice for treating proximal lesions in deciduous molars. It was seen that the most influencing three factors were child's age, followed by the child's behaviour and then oral hygiene and risk assessment.

Childs age is actually the most important factors as co-operation level of the child is equally required for the success of treatment. Childs age also helps us to determine the period for which the tooth is to be saved/preserved before exfoliation into the oral cavity. Behaviour management is another factor which alters the choice of material. Childs behaviour, according to the survey, was the second most ranked-choice, as treatment is altered in case of uncooperative child and different behaviour modifications tactics are to be used accordingly. Many minimally invasive techniques are introduced for the management of the uncooperative child. In high-risk caries, a patient treatment plan is different as compared to low-risk patient. Oral hygiene also helps us to determine the treatment plan for the child. Thus, the third-most preferred option by respondents was oral hygiene and caries risk assessment. Moisture control is one of the important factors which importantly contributes to treatment planning. In the present study, it was seen that respondents did not consider it as an essential factor as the usage of rubber dam with the introduction of advanced isolation techniques helped to control moisture.

Based on the current study, it was seen that aesthetics followed by the evidence-based success of material and affordability were the least considered factors while determining the choice of material.

In today's generation, nuclear families are increasing, which does have an effect on the expense of dental treatment. Parents are well educated and know the importance of dental treatment. Second, aesthetics in children in deciduous teeth is less preferred amongst parents. Aesthetic restoration, like zirconia crowns, requires greater tooth preparation as well as subgingival preparation. Crown preparation for preformed zirconia is more time-consuming as compared to preformed SSC crown preparation. Thus, aesthetic restoration was less preferred amongst respondents. Exfoliation of teeth in upcoming years makes it less important for aesthetics. Dentist prefers SSC more due to its cost and durability in primary molars.

  Conclusion Top

It can be concluded from this study that SSC was the most preferred restorative material of choice for treatment Class II lesion and also showed long-term success. It also stated that the excavation and then restoration is the most preferred treatment modality used while treating Class II lesions. Childs age and behaviour are the most influencing treatment factors to determine the choice of restorative material.

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Conflicts of interest

There are no conflicts of interest.

  References Top

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