Does the length of dental procedure influence children’s behavior during and after treatment? A systematic review and critical appraisal

Search strategy

A systematic search was conducted by searching electronic databases Pubmed/ Medline and Scopus for English language peer-reviewed articles published between 1970 and March 2017 using the search terms (("treatment duration" OR "treatment length" OR "appointment length" OR "dental treatment duration" OR "dental treatment length" OR "dental appointment length" OR "dental anxiety" OR "dental phobia" OR "dental fear" OR "odontophobia" OR "dental distress" OR "dental stress" OR "dentist phobia") AND ("infant" OR "child" OR "adolescent" OR "children" OR "young" OR "young person" OR "minor" OR "pediatric" OR "pediatric")). A database was created for the found records, where they were entered and duplicate entries were removed.

After searching the databases, some recognized pediatric journals in this field, including the International Journal of Pediatric Dentistry, Pediatric Dentistry, The Journal of Clinical Pediatric Dentistry, European Journal of Pediatric Dentistry and Journal of Dentistry for Children, were also hand searched. In addition, the reference lists of selected articles were manually searched in order to complement the search database.

Inclusion criteria

All the studies that had available abstract in English and assessed dental treatment duration or length, and fear/anxiety or behavior in children aged <12 years old; the participants had no confounding medical and/or psychological history and neuro-psychiatric disabilities that could influence their behavior.

Exclusion criteria

Papers having any of the below criteria were excluded: Mixed populations (unless specific data were available for the target age group); letters to editor, presentations in conferences, case reports and unpublished papers.

For qualification, all the criteria had to be either clearly mentioned in the study or later represented by the corresponding author; otherwise, the study was excluded from the systematic review. All the papers that passed the abstract screening were retrieved in their complete forms, and data extraction was conducted.

Data extraction

A standardized data extraction form was developed and pilot-tested. Two reviewers from the team independently applied the inclusion criteria when reviewing the abstracts and complete papers. The initial selection was based on the titles and abstracts of the studies. A third reviewer conducted a random check of approximately 10% of titles and abstracts to check reliability of initial screening. Disagreements were resolved through discussion. If disagreement persisted, the judgment of the third reviewer was decisive.

The following data were then extracted from the articles using the data extraction form: Assessing for dental treatment length; children's behavior, anxiety or fear during/after dental treatment; country and setting where the study was conducted (private office, dental school, clinic etc.); study’s sample size, design and randomization; context including the type of dental procedure and interventions; characteristics of participants, including age and gender; time of assessment of behavior/anxiety/fear/phobia (before, during and/or after treatment).

Effect of treatment length on children’s behavior during treatment

Four studies reported the effect of treatment length on children’s behavior during dental treatment. Davidovich et al⁸ reported that behavior during treatment was associated with treatment duration in children aged 2‒5.5 years. Aminabadi et al⁴ reported that treatment duration had a significant and main effect (P<0.001) on children’s behavior. Getz and Weinstein⁷ divided the restorative appointment into six distinct phases and reported that the length of each phase was significantly related to fear/distress-related behaviors (P=0.001). However, no relationship was found between children’s behavior and the total length of the appointment. Lenchner⁵ reported no differences in children’s behavior between long and short appointments or treatments (Table 1).

Effect of treatment length on children’s behavior after treatment

The effect of treatment length on children’s behavior after dental treatment was investigated in two studies. Lenchner⁵ reported no difference in children’s behavior between long and short appointments. Davidovich et al⁹ reported that behavior immediately after treatment was significantly related to treatment duration in 2‒3.5-year-old children (P<0.001). However, no significant correlation was found between treatment duration and behavior after treatment in 3.5‒5.5-year-old children (Table 1).

Methods of assessment of children’s behavior

Behavior during treatment was assessed using the sound, eye and motor (SEM) scale,⁴ Houpt’s scale⁸ for general behavior and two self-developed questionnaires.^5,7 In these studies the dentists rated the children’s behavior during treatment. Children’s behavior after treatment was rated by parents and dentists (Table 1).

Treatment duration and behavior of children with different ages

Even without a complete agreement among studies, the main results found in this review showed that younger children are more likely to demonstrate negative behavior with an increase in treatment duration. Aminabadi et al⁴ provided a framework within which to consider the effect of treatment duration on children with different ages. Their findings showed a significant deterioration of behavior in younger children as treatment time was extended.

Age is a well-established factor which determines children’s behavior during treatment. In fact, the child’s stage of development determines their ability to cope with dental procedures and it seems that older children have greater ability to comply with the dental treatment.^13,15,16 Most of the included studies have focused on the preschool age group, who often exhibit behavior problems and dental anxiety, requiring an increased time during dental treatment.¹⁰ Conversely, school-aged children may have developed sufficient coping skills to comply with the treatment when appropriate communication is established by the clinician.^7,10 Therefore, in order to eliminate the effect of age as a confounding variable, studies should include and investigate children with similar age, or at least in the same developmental stage.

The attention span of children in various ages is also an important determinant of their reaction to treatment length.⁴ Children generally have difficulty sustaining attention for long periods of time. Attention problems are common among preschool children and progressively develop until the late school ages. By planning a variety of clinical activities based on the child’s age and attention span, the practitioner is more likely to maintain the child’s attention and limit inappropriate behavior.^17,18 Furthermore, given these considerations, development of valid objective methods for assessing attention in preschool children could be particularly important.

Treatment duration and children’s dental fear and anxiety

All the reviewed studies have focused on children’s behavior, ignoring fear and anxiety during treatment. Anxiety and fear can be major barriers for children to accept and tolerate treatment. They are relatively common occurrences in the dental setting and may lead to BMP during treatment.^9,19 It has been reported that children with high dental fear also have other behavioral and emotional problems.^17,20 On the other hand, children’s behavior reflects their inability to cope with anxiety and fear, and behavior management techniques provide children with appropriate coping strategies.¹⁶ It is assumed that anxiety impairs children’s attention system and increases the extent to which they react to threatening stimuli by reducing the ability to inhibit incorrect prepotent responses.^21,22 Therefore, the importance of dental fear and anxiety in developing BMP and, consequently, interrupting treatment procedure should be considered as a central potential mediating factor during dental procedures for children.^19,23

The distinction between dental fear, dental anxiety and BMP is also important.¹⁹ Children with dental fear/anxiety may express uncooperative behavior and vice versa.²⁴ Therefore, in order to conduct a study related to the effect of treatment duration in children, the inclusion of children should be made by accurate identification of the existence of dental fear/anxiety or a history of BMP by incorporating appropriate measures into diagnostic protocols. Considering the fact that these conditions may affect children’s behavior during and after dental treatment, children with dental fear/anxiety or history of BMP should be excluded.²⁵ In addition, the children’s mental health status should also be considered as performed by Aminabadi et al⁴ in their study. Since neuropsychiatric disorders affect at least 5% of the child population, it is likely that dentists frequently meet children and adolescents with these disorders, who may present with BMP or fear/anxiety as part of their diseases.¹⁷ Therefore, an adequate screening focused on the problems within the neuropsychiatric spectrum should be routinely performed in studies, especially those with referred patients.

Treatment duration and children’s history of BMP

Davidovich et al⁸ evaluated children who had uncooperative behavior prior to treatment. Children’s dental fear/anxiety and history of BMP are confounding factors when treatment duration, as the cause of disruptive behaviors, is assessed among children. Moreover, it is possible that as the fear- or anxiety-related behavior increases, the length of the treatment increases presumably because of uncooperative behaviors by the child and vice versa. Interestingly, it has been noted that treatment duration of patients with anxiety or BMP is on average 40% more than that of normal patients going through the same procedure.⁷ Therefore, dentists should consider conditioning and gradual exposure to obtain cooperation in young children, and to maintain their cooperation by making the treatment as short as possible. In addition, dental practitioners could adopt a time-out policy. Although the degree of success of time-out varies, it appears to decrease patient disruptiveness in selected cases. In addition, time-out period and the frequency of time-out episodes are important considerations for its effectiveness. The time-out should be short and only be used once or twice to gain the acceptable behavior in any given child; otherwise, its failure is possible.²⁶

Treatment duration and operator’s clinical experience

The dentist’s clinical experience is also essential for establishing the adequate duration for each child’s treatment. The origin of BMP in some children is primarily due to their previous negative experiences with dental care.²⁷ Well-trained and experienced pediatric dentists may be more efficient in providing treatment in shorter course and with the least traumatic approaches which significantly contribute to the children’s behavior during and after treatment.³ Of the reviewed studies, in Aminabadi et al study⁴ a pediatric dentist served as the operator and performed treatment procedures. In the study by Getz and Weinstein⁷, 22 general practitioners and three pedodontists participated in the study. Davidovich et al study⁸ was conducted in a postgraduate clinic and private practices of two of the authors.

Complexity of treatment and interaction with the length of treatment and children’s behavior

The extent of delivered treatment and associated pain should be considered as they may interact with the length of treatment and children’s behavior during or after treatment.²⁸ Davidovich et al⁸ classified complexity of treatments in their study as simple procedures, including fissure sealants, prophylaxis, Class I and Class II restorations, and as complex, including stainless steel crowns, pulp therapy and dental extractions. Relying on the above-mentioned classification, in Aminabadi et al⁴ and Getz and Weinstein study⁷ the participants received restorative treatments which can be considered as simple procedures. Lenchner⁵ provided both simple and complex treatments for all the participants in two consecutive sessions, which allowed better understanding of the interplay between treatment type and children’s behavior during treatment. However, the complexity of treatment usually has no correlation with the duration of treatment. For instance, dental extraction is considered a complex treatment, although it was obviously shorter than a Class I restoration. Therefore, it is better to consider invasiveness of treatment in future studies as it may better present the nature of treatment.

Methodological issues

This review confirmed the effect of the procedure length on children’s behavior during dental treatment. However, all the 4 studies have their weaknesses in methodology, design and data analysis. Most of the studies had a relatively small sample size. Except for the study by Aminabadi et al,⁴ which included 450 children with a wide age range, the remaining studies had a sample size of <100 participants. Apparently, there is a lack of representative and population-based samples to understand potential differences between various treatments, ages and genders. In addition, none of the studies included sample size calculation, and participant recruitment procedures varied considerably among the studies. Future studies in this field should consider representative sampling, recruitment standardization and justification of sample size to test the associations with sufficient power.

Besides, concerns were raised on the BMP assessment quality due to poor assessors' (parents or dentists) knowledge level on this psychological matter, and the lack of inter-rater reliability. In Lenchner’s study,⁵ parents and dentists were asked to rate the children’s behavior using one simple question. The frequencies of observed behaviors by dentists were reported in Getz et al study⁷ as a dichotomous variable, which may lead to elimination or masking of certain important details. Aminabadi et al⁴ used two observers to evaluate children’s behavior during treatment, using sound, eye and motor (SEM) scale with high inter-rater reliability. In Davidovich et al study,⁸ children’s behavior during and following treatment were obtained from the records of children. As reported above, there is a relevant incoherence among the included studies in both the methods and measurement tools to rate the children’s behavior. In addition, it has been noted that the assessment of behaviors over a short period of time is more accurate than long period of time.²⁹ Therefore, in order to reach a high correlation between ratings and behavior, the dentists should rate behavior within a relatively short period of time (6‒30 minutes).³⁰

All the included studies adopted traditional analysis methods of the data obtained from observers’ ratings or grading on scales. The use of lag sequential analysis technique is advocated to identify patterns of behavior of children. In addition, the adoption of autocorrelation in the lag sequential analysis may further advance our understanding as the occurrence of certain behavior is not influenced only by treatment duration.³¹ Moreover, no study considered the clustering effect of personal characteristics and situational and environmental factors. In order to take account of some participant-specific variables, attempts to control for clustering (such as multilevel modeling) should be incorporated into sequential analysis. The traditional multivariate variable-based approach to investigate the relationships among variables does not fully explain the interplay between variables within each child. To understand the cumulative effect of all variables on each child, analyses with a person-based approach are valuable complements. In such analyses, children are studied on the basis of their unique pattern (profile) of values for variables that are relevant to the research question.³²

Implications for current practice and conclusion

Our review confirmed the existence of a relationship between treatment duration and children’s behavior in an age-dependent manner. However, the various problems surrounding the issue make the identification of optimal appointment length in pediatric dentistry problematic and undermine the validity of current suggestions about appropriate treatment duration. Our review demonstrated that there are a number of significant gaps in the current literature, including the differences among studies related to culture, study design and methodology, sampling methods and sizes, as well as the inhomogeneous measurement procedures of both dental anxiety and BMP affecting the relevance of the findings. Therefore, comprehensive clinical investigations on how the treatment length influences child’s anxiety and behavior during and after treatment are recommended. The focus not only on single behavioral elements but also on multidimensional assessment of children, including emotional, behavioral, cognitive and physiological components and response systems, may prove to be beneficial. In addition further research is needed to develop consistency in the assessment of child anxiety and behavior with sophisticated and valid behavioral codes.