Pain intensity and discomfort are side effects
during orthodontic treatment by fixed orthodontic appliances.(1)
Pain and discomfort are common place after insertion of an initial aligning
archwire. The prevalence, magnitude, and time course of pain, after insertion
of the initial leveling archwire, had previously been reported by several
groups of investigators.(2,3) The level of pain reported
after archwire placement is believed to be greater and more prolonged than that
following extraction of teeth.(4) Some researchers
even mentioned that, 90 per cent of their orthodontic patients reported that,
their treatment was painful and 30 per cent of them considered ceasing
treatment prematurely because of the pain they experienced.(5)
Within first few hours of insertion of first archwires, the majority of
patients report experiencing some pain, after 24 hours pain is reported by up
to 95 per cent of patients undergoing therapy with fixed appliances.(2)
Erdinç and Dinçer(6) concluded that, initial pain is
perceived at 2 hours and peaks at 24 hours during orthodontic treatment with
fixed appliances. Patients’
pain is one aspect of oral health-related quality of life (OHRQoL), a
relatively new concept in the oral health sciences. Pain related to orthodontic
treatment leads to poor oral health which can affect physical, psychological,
and social conditions of the patient, which in turn affect patient’s Quality Of Life (QOL).(7,8)
Pain from orthodontic treatment has been shown to have negative effects on
oral hygiene efforts and to be a major reason for missing appointments; in
addition, almost all orthodontic patients reported pain when chewing and biting
foods of a firm or hard consistency, causing them to change their diet.(2,9,10)
The pain within the first 48 hours is so disturbing that approximately 20
per cent of patients reported awakened at night and it causes some patients to
take analgesic medication.(2,11) So, many researchers were
interested in assessing the determinants and responsiveness of the OHRQoL.(12-15)
The variations in individual responses to the insertion of the
archwire led several investigators to look for factors which could be helpful
in predicting which patient will experience the most pain and how to manage
this pain, so many researchers (16-26) studied how we could
decrease the level of pain or even to prevent it by different means, by testing
different types and gauges of wires, different bracket systems and techniques,
and different mechanics, in order to produce a more
biologic movement effect that avoids compromising the teeth and the periodontal
support. As less pain intensity means less analgesic consumption and
less effect on QOL of the patient.(27) On the other hand,
analgesics consumption by fixed orthodontic patients, and what types that could
be used more safely to control orthodontic pain, were the target for many groups
of researchers.(18,19,28-30) Giving the orthodontic patients
specific analgesics, prior to and after fitting the orthodontic appliance, will
decrease or prevent the pain expected to be experienced by the patient.
Xiaoting et al(31) concluded that,
analgesics are still the main treatment modality to reduce orthodontic pain.
However, the pharmacologic actions as well as their side effects should be
identified before prescribing these medications in routine clinical practice.
Xiaoting et al(31) also confirmed
that, there was no difference in pain control between ibuprofen, acetaminophen,
and aspirin. They declared that, some long-acting nonsteroidal
anti-inflammatory drugs NSAIDs and cyclooxygenase enzyme COX-2 inhibitors are
interestingly recommended for their comparatively fewer side effects, and their
preventive use is promising. Other means for decreasing pain perceived by
orthodontic patients were suggested by many researchers like: chewing gum,(32)
vibratory stimulation,(33) and low-level laser therapy.(34)
Some researchers concentrated on the relationship between personality
traits, pain perception and attitude toward orthodontic treatment. They found
that pain perception in treated subjects was lower in patients with previous
knowledge of orthodontic treatment, and more
positive attitude was found in patients who experienced less pain during
orthodontic treatment.(3, 35-37) Certainly, potential
patients have heard about how painful orthodontics can be, but they all go
through the treatment anyway. Therefore, pain perception is real, and must be
accepted as part of routine orthodontic treatment.(15) although orthodontics has developed significantly in
several areas in the last decades, pain has been a constant worry for
professionals and patients undergoing orthodontic treatment. However, few
experimental studies have been conducted on this important symptomatology. This
justifies going deeper into this area of research to provide new procedures to
deal with the pain reported by the patients.(9,38) This
study was designed to investigate the pain
perception in orthodontic patients treated by fixed appliances, explore age and
gender differences in pain perception, and determine the effect of this pain on
their "Quality Of Life".
Methods
Ethical approval for this study was provided by the
Human Research Ethics Committee- Royal Medical Services- Jordan. The sample of this study was composed primarily of 289 patients, who
were chosen from the patients of the orthodontic clinic at Princess Haya
Al-Hussein Hospital over the period from March 2010 to October 2011. All
patients were taken according to their order on the waiting list randomly with
the only condition that they fullfill the inclusion criteria requirements. The compliance
of patients was more than 95%. Only 13 cases from the
primary expected sample were excluded, five cases due to movement to another
region and couldn't attend on the first recall visit, two cases due to very
severe pain that they couldn't tolerate, so they asked for debonding within the
first few days after bonding of the attachments, six patients didn't attend the
clinic on the scheduled appointment and show no interest to complete the
questionnaire. The final sample of this study was composed of 276 patients, who
were divided according to age into two main groups Adolescents (A) with their
ages less than 18 years and Adults (B) with their ages equal or above 18 years.
The Adolescents group (A) was composed of 169 patients (117 female patients
with the mean age was 14.8±1.7 years, and 52 males with the mean age was
15.0±1.5 years), while the Adult group (B) was composed of 107 patients (72
female patients with the mean age was 22.7±5.6 years, and 35 males with the
mean age was 23.4±5.3 years), Table I.
The inclusion
criteria for the sample selection were including the following:
1. Patients had no history of systemic or congenital
diseases.
2. Patients had permanent dentition.
3. Patients had good healthy gingival tissues with fair
to excellent oral hygiene habits.
4. No dental extraction was done since at least one month
if there was any.
5. All patients need to be treated by fixed orthodontic
appliances.
6. Any carious teeth should be treated before attachments
fitting.
7. No presence of local intra or extra oral diseases or
lesions like ulcers or herpes labialis at time of bonding of the attachments,
which would make it difficult to differentiate between the pain sources.
8. Patients were not using any medications that could
affect pain perception.
Patient were already have undergone study impressions, treatment
planning, separators, and molar bands fitting steps. The patients were asked to
participate in the study on the day of placement of the fixed orthodontic
appliance. Direct bonding of 0.018" Roth prescription brackets*
were done for all participants. Brackets were placed by the same orthodontic
practitioner from the second premolar to the contra lateral one for both upper
and lower dental arches. The initial wire was 0.012* round
martensitic active nickel-titanium (NiTi) alloy archwire** with full engagement by elastic O-ties*** for all cases. Similar oral
hygiene and appliance maintenance instructions were given to both groups and
all patients received a supply of relief wax.
Instructions were given to all participants to record any pain killer
medication consumption. On the recall visit, patients were asked to complete a
questionnaire (Appendix 1) in a 5-10 minute interview with the practitioner and
the assistant who explained the questionnaire before its completion by the
participants. Reliability of a questionnaire in assessing
experiences of adolescents in orthodontic treatment was tested by Feldman et
al,(13) who found the test-retest reliability excellent. The questionnaire was composed of two parts: The first part was
concerned with pain intensity felt during the placement visit (T1), immediately
after (T2), one day (T3), two days (T4), and one week after placement of the
appliance (T5), and on the recall visit day (T6). The recall visit was arranged
after one month of the fixed appliance bonding visit for each patient, during
this visit the wire was exchanged to 0.016" NiTi alloy archwire++.
The
patient was asked to fill the questionnaire immediately after finishing the
recall visit. The patient’s pain experience was assessed by using a 5-point
Likert scale with five choices, starting on the left end by the descriptive
terminology "No pain" =0 mark, "mild pain" =1 mark,
"moderate pain" =2 marks, "severe pain" =3 marks, and
ending on the right side by "very severe pain" =4 marks. Pain experiences of the patients were recorded according to their own
experience and how they felt on the different time occasions from T1 to T6.
Pain scores were collected and statistically analyzed. Mean of pain intensity
scores were calculated for each event separately. Inter- and intra-group
differences in means of pain scores were investigated. The second part of the
questionnaire was concerned with the effect of pain related to the fixed
orthodontic appliance on the quality of life (QOL) of the patients including
any drug consumption related to orthodontic treatment. These questions were
used by other studies,(14,39) in which their
test-retest reliability was considered excellent. These questions were found to
be suitable and representative for the present study. This part was composed of
six questions of Yes and No answers; each question was given 4 marks for
"Yes" answer and 0 mark for "No" answer. These six
questions were designed to find out if the pain from the fixed orthodontic
appliance affected the patient daily life and activities, caused the patient to
change the usual diet, made the patient's teeth hurt on biting or chewing, made
it difficult for the patient to brush his/her teeth, disturbed the patient's
normal sleep, and necessitated him/her to take analgesic medication to relief
pain. Any pain relief medication taken by the patient should be written in type
and dosage. The marks deserved for these six questions were summed together, to
form the QOL score (from 0-24 out of 24). Higher QOL score meant that, there
was more effect of the fixed appliance-induced pain on the QOL of the patient.
Means of QOL scores were calculated for both groups, inter- and intra-group
differences were tested statistically. Also, the correlation of the QOL scores
with the age of the patients was tested for the whole sample. The ratio of patients who administered analgesic
medication was calculated for both groups, and for those patients, the type and
dosage of the medication was recorded to find the mean days of consumption of
medication due to orthodontic pain. In addition, all types of analgesic
medication taken by our patients were investigated to find the most popular
among them. For both groups, inter- and intra-group differences in means of
days of medication consumption were tested statistically.
Statistics
Reliability of the
questionnaires in assessing orthodontic responses and pain perception by the
orthodontic patients was tested by many researchers and found to be good to
excellent.(10,13) Data of this study was gathered, tabulated,
and statistically analyzed. Data analysis included descriptive and analytic
statistics obtained with the Statistical Package for the Social Sciences (SPSS)
software, version 16. The descriptive
analysis was done for both groups and the subgroups including age, gender, pain
intensity scores, QOL scores, and days of medication usage. Independent samples
t-test was used in this study to find the significance of difference in inter-
and intra-group pain score means on the different time intervals (T1-T6), QOL
means, and mean days of medication usage. Bivariate Pearson correlation test
was used to find the significance of correlation of the QOL scores and pain
intensity scores with age of patients among the whole sample. The significance
level for this study was considered as P value ≤ 0.05.
Results
Of the study sample, 276 subjects (95.5%) completed the study
successfully. The other 13 subjects (4.5%) who failed to comply with the study
were eliminated from the study and their results were excluded from data
analysis. Gender distribution and mean age were cleared in Table I, for both
groups.
Pain Course:
Frequency and ratio of patients who reported feeling pain and discomfort
were calculated for each of the six time intervals from T1 to T6 (Table II).
Means of pain intensity scores were calculated, for both groups, at each time
event separately. Inter- and intra-group comparisons were done as expressed in
Tables III and IV. Ratio of patients experienced pain increased sharply to
reach up to 90.2% on same day of bonding. It continued to be high after one day
(83.7%), and then, it started to decrease after two days of bonding (62.7%)
down to 33.3% after one week. On the recall visit, only 14.5% of the whole
study sample reported that, they had pain of low intensity (mild to moderate). The
results of this study revealed that, 3.7% of group B felt mild pain at the
bonding visit (T1), while, in group A only 0.6% felt mild pain. Immediately
after bonding and on same day (T2), pain intensity ranged from no pain to
severe pain. 91.6% of group B patients felt pain from orthodontic appliance as
compared to 89.3% of group A, most of them felt mild to moderate pain. On the
second day (one day after bonding (T3)), 90.7% of the adults group felt pain
with its severity started to decrease, while, in the adolescent group 79.3%
felt pain. After two days of bonding (T4), less percentage of patients
perceived pain (66.4% of group B and 60.4% of group A). Pain continued with
27.8% of group A and 42.1% of group B, after one week of bonding (T5). On the recall visit (T6), 21.5% of group B
and 10.1% of group A had pain, but, their pain was of milder intensity. Regarding
the means of pain intensity scores, no significant intra-group differences
(gender differences) were found in both groups as illustrated in Table III. On
the other hand, significant inter-group differences were found on T3,T4, T5,
and T6 intervals, with P values equal .004, .050, .001, and .004 respectively
(Table IV).
QOL: The effect of pain experienced during fixed orthodontic treatment
on the oral related QOL was measured in both groups. Frequency and
ratio of patients had an effect from pain of braces on their QOL were
summarized in Table V. While, the means of QOL scores among
both groups were summarized in Table VI. The results of this study revealed
that, there were no significant gender differences among each of group A and
group B, on the other hand, these results revealed a
highly significant difference between both groups, with P value <.01 (Table
VI).
Age: The patients were separated according to their ages into two groups
A and B. the age for group A was < 18 years (n=169) and for group B it was
≥18 years (n=107), means of age for the participants and their standard
deviations were summarized in Table I. Differences were found between both
groups in means of pain intensity scores (on T3, T4, T5, and T6), means of QOL
scores, and means of days of analgesic consumption, as summarized in Tables IV
and VI.
The correlation between age and QOL scores (Table VII)) was found highly
significant for the whole sample, as P value < .01. In addition to that, the
correlation between age and pain intensity scores was found significant on T2,
T5, and T6 time intervals, with P value < .05 as shown in Table VII.
Gender: Both groups A and B were divided into subgroups according to
gender. Among group A, females had greater pain intensity scores mean than
males on T1-T5 intervals, while on T6, males had greater mean of pain intensity
scores than females. Also, females showed greater effect of pain from braces on
their quality of life than males. In Addition to that, females had a little bit
higher mean of days of analgesic consumption than males. In spite of these
results, no significant gender differences were found in means of QOL scores,
days of medication consumption, and pain intensity scores, except for the means
of pain intensity scores on T6, with P value < .05 (Table III). On the other
hand, among group B, females had higher pain score means than males on T4 and
T6 intervals, while, males had higher pain score means on T1-T3, and T5
intervals. Also, males had more effect of pain from braces on their QOL than
females. Means of days of analgesic consumption were found to be equal in both
sub groups. All these differences among group B were found to be insignificant
in this study.
Analgesic consumption: No specific prescription for pain medication was
dispensed to the patients. Patients' instructions on bonding day tried not to
mention the world "pain", in order not to affect the patient
psychological response and his expectation or force him to take analgesic
medication in advance. The orthodontist instructions point out that, if you
feel any discomfort you may use what you usually use for mild headache. So,
every patient was free to take any medication he/she felt necessary. Patients
were asked to respond whether or not they had taken any analgesics. If the
patient's answer was yes, then the type of analgesic, duration of taking it,
and dosage should be reported. Ratio of patients reported taking different
types of analgesics, and means of days of analgesic consumption were
summarized, for both groups, in Tables VIII and VI, respectively. Means of days
of analgesic consumption were compared in this study for both groups; the
results revealed that, there were no significant intra-group differences could
be found among either of group A or B, although, males had higher means of days
of medication consumption than females. While, the inter-group comparison
showed that, a significant higher mean of days of analgesic consumption was
found in group B more than in group A, (Table VI).
Discussion
In order to
eliminate inter-examiner variability and subjective bias, all patients were
treated and interviewed by the same clinician. Attempting to eliminate the
effect of variables, other than age and gender, on results, same type of
braces, archwires, technique of bonding, timing, and ligature elastics were
used for the entire study population. Results of this study revealed that, the
highest ratio of patients experienced pain was on same day of bonding. This
ratio decreased slightly in the second day after bonding. On the third to the
seventh day after bonding, patients' ratio that experienced pain dropped
gradually and significantly. On the recall visit, only few patients of the
whole study sample complained from pain of low intensity (mild to moderate).
These results
were consistent with the results of other studies which showed that, pain
started 2-4 hrs after insertion of the initial wire and peaked up after 24
hours. These studies also showed similar ratios of patients reported pain from
braces at same time intervals.(2-6,11,24) Among group B, male
patients experienced pain more than females during the first two days after
boding, while after two days up to the recall visit, higher ratio of female
patients experienced pain more than males. On the other hand, among adolescent
group, females experienced pain more than males on T1-T3 and T5 intervals,
while, males showed higher ratios on T4 and T6 intervals.
There were no significant
gender differences (P>0.05) in pain intensity scores for both Adolescent and
Adult groups. On the other hand, reported pain experiences over one week
following bonding of the appliance were significantly higher (P<0.05) in
group B than in Group A. However, there was no significant difference
(P>0.05) in means of pain scores during attachment placement or immediately
after. The results of this study revealed a significant correlation between age
and level of pain perceived among the entire sample population. These
conclusions were in contrary with those obtained by Abu Alhaija et al,(3) who documented the gender as the
only variable affected subjects' average pain perception. Their conclusions
were consistent with those obtained by Ren et al,(24) who
found a significant difference in pain perception between males and females.
They reported
that, the highest frequency of pain was in the 13-16 year old age group, while
no difference in pain intensity between age groups could be reported. In
addition, Sheurer et al(2) found that, there was a
significant gender difference in pain perception, but, no age difference in
pain intensity. On the other hand, many studies demonstrated the patient age as
a main determinant of the pain perception level. Jones et al,(4)
demonstrated that there are no significant gender differences in pain
perception of orthodontic patients. A further support of our observations by
Erdinç et al,(6) whose results were comparable to
those obtained by this study. Other study conducted by Scott et al,(16)
found no gender, appliance type, or age effect on level of pain intensity;
they documented post bonding time as the only determinant. In this study, the QOL of
the patients was affected by pain resulted from the fixed orthodontic appliance
and the aligning wire. The overall oral health-related QOL of the orthodontic
adult patients was affected more than adolescents. For group A, the overall
oral health-related QOL score was 3.29±4.3 with a 13.7% decrease in QOL value.
In group B, QOL score was 5.46±5.5 with a 22.8% decrease in QOL value. There
was a significant difference in QOL values between group A and group B. Main
effects on QOL observed in this study, were analgesic consumption, changing diet
consistency, teeth hurt on chewing and biting, difficulty in brushing teeth,
and to a lesser degree, daily life activity and sleep. In the adolescence age
group, females reported a higher change in their QOL compared to males. Apart
from analgesics consumption which reported to be higher in females, the effect
of the orthodontic treatment on males' QOL was higher than on the females' QOL
of the adult group. Although a difference in QOL scores between female and male
patients was noted, this difference is not statistically significant. Our
results were similar to those obtained in previous studies,(1,2,10,39)
in which, an obvious effect of
pain due to braces on the QOL of patients including: changing consistency of
foods in their diet, difficulties in chewing and biting, analgesic consumption,
and daily life activity was reported. Erdinç and Dinçer,(6) although
reported that 50% of patients had some problems in their daily activities
during the first three days of fitting the archwire, they considered their
findings statistically insignificant. In order to decrease the effect of pain
on the QOL of the patients, Shalish et al(20)
recommended that the most appropriate treatment modality in relation to
Health-Related Quality of Life parameters should be performed. In contrast to our results, other studies showed a relatively low ratios
of patients used analgesics to relief pain caused by braces. Krukemeyer et
al,(39) reported that 26.5% of their sample used
analgesics to relief pain. Sheurer et al,(2) and Tecco
et al(19) reported ratios of 16.2%, and 16.5%
respectively. In this study, relatively high ratios of patients used analgesics
were observed. 49 patients (45.8%) of adult patients and 66 of the adolescent
patients (39.1%) used pain killer medications. For most of the patients, the
onset of taking analgesics was one day after the appliance bonding. Females
were the dominant in analgesic consumption in both adolescent and adult groups.
The results of this study revealed that, there was no significant gender difference
could be found in both groups in mean days of analgesic consumption. While, a
highly significant age difference was found in mean days of analgesic
consumption. The relatively high ratio of analgesic consumption observed in
this study, could be related to cultural differences or lack of adequate
information given to patients by their orthodontist. Bergius et al,(1) recommended that the patient should be carefully and adequately
informed about each step in the treatment, expected complication and discomfort
in order to enhance their compliance with the treatment. They emphasized on the
importance of managing patients whom proved to be anxious and have low pain
tolerance with further reassurance, discussion, and relaxation exercises. There
recommendations were in agreement with Sheurer et al,(2) who
claimed that perceived pain and analgesic consumption would decrease if the
patient was efficiently informed about the discomfort that would be
experienced. The decision of taking analgesics should not be left in hands of
adolescent patients, the orthodontist should identify the more anxious and
afraid patients and should prescribe certain type of analgesic with the least
undesirable effects on patient QOL. The importance of prescribing analgesic
with least side effects, the least possible effective dose, and appropriate
intervals was suggested by Patel et al.(30) Recent
researchers,(28-30) after examination of different types of
analgesics, found that the use of non steroidal anti inflammatory drugs
(NSAIDS) is the preferred method to control pain related to fixed orthodontic
appliances. Naproxen sodium, Aspirin, Ibuprofen, and Acetaminophen found to be
equally effective in pain control and relatively safe. In this study, different
types of analgesics were used by the patients including, Acetaminophen,
Ibuprofen, and Diclofenac Sodium. Further research in this important issue
should be done, to find the most appropriate way for decreasing or even
preventing the pain that our fixed orthodontic patients could feel during their
treatment period.
Conclusions
From the results
of the present study it could be concluded that:
- The highest
ratio of patients complained from pain was on the same day of bonding,
this patient's ratio decreased gradually over the following successive
days of the study.
- Pain
intensity reported to be the highest in the second and third days after
bonding. This intensity gradually decreased to a mild-moderate intensity
after one week.
- There was a
significant difference in number of patients who experienced pain and pain
intensity between the adult and adolescent age groups; being higher in the
adult group.
- There was
no significant difference between males and females in pain intensity and
number of patients who reported pain in both groups.
- The effect
of pain resulting from fixed orthodontic appliances on QOL was higher in
the adult patients compared to the adolescent patients.
- The main
items of the QOL affected by fixed orthodontic treatment were analgesic
consumption, changing of diet, and dental pain on chewing or biting.
- Analgesic
consumption was higher in adult patients than in adolescent patients, as
well as, higher in female patients compared to males.
Acknowledgement
I would like to thank Mrs Zulfa Al-Majali, the assistant nurse at the orthodontic
clinic-Princess Haya Al-Hussein Hospital, for her continuous dedicated
commitment to this study by her great assistance in both patients' preparation
and patients' interviews.
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