International Journal of Applied Dental Sciences 2015; 1(3): 15-19 

ISSN Print: 2394-7489

ISSN Online: 2394-7497
IJADS 2015; 1(3): 15-19 Pregnancy and Orthodontics: The Interrelation
© 2015 IJADS
www.oraljournal.com
Received: 11-04-2015 Uday Nandkishorji Soni, Mayuresh J. Baheti, Nandlal G. Toshniwal,
Accepted: 13-05-2015 Ashwini R. Jethliya
Dr. Uday Nandkishorji Soni Abstract
PG Student,
Pregnancy is one of the most wonderful phases in a woman’s life. There is no any health reason why a
Dept. of Orthodontics and
pregnant woman cannot wear braces. Pregnancy may reduce velocity of Orthodontic Tooth Movement
Dentofacial orthopaedics, Rural
Dental College, Pravara Institute and subsequently increase treatment period, but patients should not be worried about get in trouble during
of Medical Sciences, Loni – pregnancy and orthodontic treatment, because the duration of orthodontic treatment is often more than
413736, India. pregnancy period. This article mainly emphasize on the collective effect of pregnancy related hormonal
changes, drugs used in pregnancy, changing habits during pregnancy and certain condition during
Dr. Mayuresh J. Baheti pregnancy like gingivitis on the orthodontic tooth movement.
PG Student,
Dept. of Orthodontics and Keywords: Orthodontics, Pregnancy, Gingivitis, Hormones, Drugs
Dentofacial orthopaedics, Rural
Dental College, Pravara Institute 1. Introduction
of Medical Sciences, Loni – Pregnancy is the most life altering experience in a woman’s life. It is a common saying “when
413736, India. you look good, you feel good”. It’s a fact that wearing braces and correcting your smile can be
Dr. Nandlal G. Toshniwal
a hugely life altering experience too! It is important for the pregnant woman to not only look
Professor and HOD, good, but also to feel good inside out as this will have a whole lot of impact on her well-being
Dept. of Orthodontics and as well as that of her unborn child. Getting your smile fixed and enhancing your appearance
Dentofacial orthopaedics, Rural can also do much of the same things.
Dental College, Pravara Institute It’s a fact the people are naturally drown toward pleasant faces. An enhanced appearance will
Of Medical Sciences, Loni –
413736, India.
also change the way you relate to others by increasing your self -confidence and helping you
converse, smile and laugh with ease. If you're taking orthodontic treatment, and suddenly find
Dr. Ashwini R. Jethliya out that you are pregnant, there is no need to be tensed. There is no reason why you need to
B.D.S. Private Practitioner postpone your orthodontic treatment till after your delivery.
At Majalgaon. Dist Beed The main aim of this article is to emphasis theeffects of hormonal changes in Orthodontic
Maharashtra, India.
treatment, patient education, oral hygiene maintenance and preventive and treatment strategies
for the management of gingival health in orthodontic patients during pregnancy.

History taking of the pregnant lady

Like any other form of dental care, before starting orthodontic therapy, a thorough and detailed
medical history is critical especially when patient is pregnant. However, in case of pregnancy,
it is important to get the opinion of the gynaecologist if any known complications are to be
expected.
A history of current medications is also valuable because various drugs have oral side-effects
and may influence the course of the orthodontic therapy. Drugs such as non-steroidal anti-
inflammatory drugs, hormone supplements and vitamin D metabolites could probably cause a
reduction in tooth movement during orthodontic therapy. Any previous medical conditions
such as pregnancy induced diabetes mellitus or previous pregnancy complications are
important to know in advance before starting orthodontic treatment [1, 2].
A complete dental history provides the orthodontist knowledge about the patient’s attitude
Correspondence towards dental- care and patient’s priorities. It is important that the orthodontists must be more
Uday Nandkishorji Soni
PG Student, active and capable of diagnosing gingival and periodontal problems. If the patient already has
Dept. of Orthodontics and signs such as gingival inflammation and poor oral hygiene, it may be wise to start orthodontic
Dentofacial orthopaedics, Rural therapy after the pregnancy because due to braces the maintenance of oral hygiene becomes
Dental College, Pravara Institute difficult. It is especially important to take into account the hormonal and physiological
of Medical Sciences, Loni – changes that will be anticipated during the course of pregnancy.
413736, India.
Patient’s perception of their own health is considered to be an important aspect of their
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psychosocial make up and potential compliance. It is important 3. The third form, estriole, is expressed primarily during
for the orthodontist to know if the patient is self-motivated and pregnancy.
enthusiastic about receiving orthodontic treatment or they are Estrogen is considered to be the most important hormone
forced by someone else for it. affecting the bone metabolism in women. It inhibits the
Certain factors that need to be kept in mind before going ahead production of various cytokines which are involved in bone
with braces in pregnant women are: resorption by stimulating osteoclast formation and osteoclast
1. Pregnancy induced gingivitis and periodontitis. bone resorption. It also inhibits osteoblasts’ responsiveness to
2. Hormonal changes affect tooth movement. PTH. Estrogens do not have any anabolic effects on bone
3. Effect of various drugs in pregnancy and tooth movement. tissue; they directly stimulate the bone forming activity of
4. Eating habit and craving during pregnancy and its effect osteoblasts.
on orthodontic treatment. Studies have shown that estrogens decrease the velocity of
tooth movement [1]. Oral contraceptives, taken for long periods
1) Orthodontic consideration for gingival health during of time, can influence the rate of tooth movement. Androgens
pregnancy also inhibit bone resorption, modulate the growth of the
Gingivitis is caused by several factors they may be local or muscular system, and may affect the length and results of the
systemic factors. Among systemic factors, the role of orthodontic treatment.
hormonal changes during pregnancy is well-established.
Although, the presence of fixed orthodontic appliances alone Progesterone
may not cause gingivitis, factors like pregnancy and poor oral Progesterone has been shown to increase gingival exudates,
hygiene combined together could precipitate acute gingival affect the gingival vascularity and integrity of the capillary
inflammation that may progress to a periodontal condition in a endothelial cells.4The presence of increased sex hormones
patient receiving orthodontic therapy. Orthodontic appliances during pregnancy may cause epithelial separation and an
could act as a potential plaque retentive source and aggravate increase in vascular permeability. Vascular and hormonal
inflammatory reactions that are seen during pregnancy. During changes may increase the gingival crevicular fluid and
pregnancy, hyperplasia of the gingival tissues, also known as aggravate response to plaque.
pregnancy epulides, may be due to poor oral hygiene, He et al. studied the effect of progesterone on orthodontic
inadequate nutrition, or systemic hormonal stimulation [3]. tooth movement (OTM). He found that progesterone influence
However, during pregnancy, because of the presence of the periodontal reconstruction on OTMs in pregnant rats and
established gingivitis in some patients, the condition usually may be helpful in alveolar bone formation [10]. Long-term
can progress to an irreversible breakdown of the periodontium [4]. progesterone administration could reduce the rate of tooth
However, especially during pregnancy, in cases that have pre- movement [11]. Osteoclasts are primarily observed 2 days after
existing gingival inflammation, presence of orthodontic force application. But there is lower number of osteoclasts in a
appliances could increase the demand of rigorous oral hygiene pregnant woman 2 days after appliance insertion. This
maintenance and in patients who lack that self-motivation; the decrease in osteoclast number may be due to the gradual
periodontal condition may get aggravated when orthodontic increase of estrogen and progesterone at early phases of
appliances are present in the oral cavity. It is known that fixed pregnancy. It has been suggested that maximum osteoclasts
appliances can act as plaque-retaining devices. However, when recruitment happens 5-7 days after force application.
coupled with pre-existing gingival inflammation that may be
present in a pregnant patient, there could be fast progression Relaxin
towards periodontal disease. There is a lack of awareness Relaxin has been known as a pregnancy hormone. It is
regarding oral health-care issues among patients who are released just before child birth to loosen the public symphysis,
pregnant and choose to seek orthodontic treatment. Our so that the relaxed suture will allow widening of the birth canal
emphasis is on patient education, oral hygiene maintenance for parturition. In 2005, Liu and colleagues showed that the
and preventive and treatment strategies for the management of administration of Relaxin might accelerate the early stages of
gingival health in orthodontic patients during pregnancy. orthodontic tooth movements in rats [12]. Stewart and
Systemic factors that cause gingival inflammation can be colleagues used gingival injections of Relaxin to relieve
broadly classified into genetic, haematological, hormonal, rotational memory in the connective tissues of maxillary
metabolic and environmental factors. Gingivitis and gingival lateral incisors that had been orthodontically rotated. In 2000,
hyperplasia have been associated with hormonal changes as Nicozis and colleagues suggested that Relaxin might be used
seen during puberty, pregnancy and menopause. This belief is as an adjuvant to orthodontic therapy, during or after tooth
also supported by research that report an increase gingival movement, for promotion of stability, for rapid remodelling of
inflammation in women taking steroid hormones, oral gingival tissue during extraction space closure, for orthopedic
contraceptives and other drugs that contain oestrogen and expansion in non – growing patients, by reducing the tension
progesterone [5, 6, 7]. Studies have shown that pregnant women of the stretched soft tissue envelope, particularly the expanded
have an increased incidence of gingival inflammation palatal mucosa, after orthognathic surgery.
compared with non-pregnant women [8, 9].
3) Effect of various drugs in pregnancy and tooth
2) Hormonal changes that affect tooth movement:- Estrogen movement
Estrogens are female sex hormones that occur naturally in According to WHO (1966), drug is any substance or product
three forms. that is used to modify or explore physiological systems or
1. The first and most prominent form of estrogen is estradiol, pathological states for the benefit of the recipient. During
which is produced from menarche to menopause and is orthodontic treatment, drugs are prescribed to manage pain
important in the regulation of the estrous cycle. from force application to biological tissues, manage
2. The second form is estrone, produced after menopause, temporomandibular joint (TMJ) problems and tackle some
when the total amount of estrogens has decreased. infection throughout the course of treatment. Apart from these

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drugs, patients who consume vitamins, minerals, hormonal amount of calcium and phosphorus levels. Vitamin D receptors
supplements, during pregnancy and other compounds for the have been demonstrated not only in osteoblasts but also in
prevention or treatment of various diseases can also be found osteoclast precursors and in active osteoclasts. Stimulatory
in every orthodontic practice. Some of these drugs may have action of vitamin D on osteoblasts can help stabilize
profound effects on the short- and long-term outcomes of orthodontic tooth movement.
orthodontic practice. Hence, it is necessary to review the In 1988, Collins and Sinclair demonstrated that
mechanism of action and effects of commonly used drugs on intraligamentary injections of vitamin D metabolite, 1,25-
tissue remodelling and orthodontic tooth movement. dihydroxy cholecalciferol, caused increase in the number of
osteoclasts and amount of tooth movement during canine
Analgesic retraction with light forces [14].
Analgesic is a drug that selectively relieves pain by acting on In 2004, Kale and colleagues observed that local applications
the CNS or peripheral pain mechanisms, without significantly of vitamins enhanced the rate of tooth movement in rats due to
altering consciousness. the well-balanced bone turnover induced by vitamin D [15]. In
Effect of NSAIDs on tooth movement 2004, Kawakami observed an increase in the mineral
Most commonly used medications in orthodontics are for appositional rate on alveolar bone after orthodontic force
control of pain following mechanical force application to application; they suggested that local application of vitamin D
tooth. Inhibition of the inflammatory reaction produced by could intensify the re-establishment of supporting alveolar
PGs slows the tooth movement. Recent research demonstrated bone, after orthodontic treatment [16].
the molecular mechanisms behind the inhibition of tooth
movement by NSAIDs. The levels of matrix 4) Eating habit and craving during pregnancy and its
metalloproteinases (MMP9 and MMP2) were found to be effect on orthodontic treatment
increased, along with elevated collagenase activity, followed Some women experience unusual food cravings while they are
by a reduction in procollagen synthesis which is essential for pregnant. A regular desire for sugary snacks may increase your
bone and periodontal remodeling. The whole process is risk of tooth decay.
controlled by inhibition of cyclooxygenase (COX) activity,
leading to altered vascular and extravascular matrix Oral health care during pregnancy
remodeling, causing a reduction in the pace of the tooth Many of pregnant women receive any dental care during
movement. pregnancy. Women with lower socio-economic strata tend to
Aspirin:- avoid visiting dental offices during pregnancy. In addition,
Many pregnant women take this medicine as pain killer but there is a lack of awareness among women about the potential
some of pregnant ladies are prescribed this medicine as for risk of poor pregnancy outcomes and periodontal disease. Thus
blood thinner. Due to some reasons the blood of pregnant lady dental care visits are reduced during pregnancy and some
get thicker and there is clot formation in placenta due to this choose to wait until after delivery to address any oral
the foetus does not get good amount of blood supply so the healthcare needs. Studies have shown a correlation between
growth of foetus is either retarded or there are chances of periodontal disease and increased risk of preterm low birth
foetal death. To reduce these chances gynaecologist prescribe weight babies. In addition, there is research to support that
a blood thinner. These drugs should be to taken orally or treatment of periodontal disease could reduce preterm births.
intravenously. Acetylsalicylic acid and the related compounds,
and their action result from inhibition of COX activity, which Orthodontic consideration and management
converts unsaturated fatty acids in the cell membrane to PG’s. There are some factors that could make orthodontic treatment
Clinical experience shows that orthodontic tooth movement is uncomfortable. For instance, the first trimester of pregnancy
very slow in patients undergoing long-term acetylsalicylic can manifest itself in the form of morning sickness. Several
therapy. Salicylate therapy decreases bone resorption by women actually suffer through morning sickness throughout
inhibition of PGs’ synthesis and may affect differentiation of their pregnancy. Morning sickness can have you feeling
osteoclasts from their precursors. Therefore, it is fatigued and dehydrated. Throwing up everything you eat can
recommended that patients undergoing orthodontic treatment actually lead to malnutrition, and in severe cases, a pregnant
should not be advised to take aspirin and related compounds woman may need to be hospitalized. So care should be taken
for longer period during orthodontic treatment. not give them appointments in the morning time. All these can
be bad enough on their own, but when you combine them with
Bisphosphonates the soreness and discomfort that comes with wearing braces, it
Bisphosphonates (BPNs) have strong chemical affinity to the can all be hard to take. The initial days of your braces
solid-phase surface of calcium phosphate; this causes treatment can be discomforting and even painful. A pregnant
inhibition of hydroxyapatite aggregation, dissolution, and woman may find that she can’t eat her food, because her teeth
crystal formation. Bisphosphonates cause a rise in intracellular hurt too much, and she needs to eat to keep her energy up.
calcium levels in osteoclastic-like cell line, reduction of Allow women who have a high risk of producing offspring
osteoclastic activity, prevention of osteoclastic development with oral clefts to be targeted with folic acid supplementation
from hematopoietic precursors, and production of an osteoclast (mothers who already have a cleft affected child or those on
inhibitory factor. medications which may induce oral clefts). Anti- convulsants
Studies have shown that BPNs can inhibit orthodontic tooth including valproate, carbamazepine, and phenytoin and
movement and delay the orthodontic treatment.13 Topical methotrexate have been observed to induce oral clefts in
application of BPNs could be helpful in anchoring and humans.17
retaining teeth under orthodontic treatment. Light and continuous force should be used as we know that
periodontium is susceptible to breakdown with heavy forces
Vitamin D and it’s advisable to limit the visits to shorter appointments to
Vitamin D and its active metabolite, 1,25,2(OH)D3, together avoid the patient being in extreme supine position especially
with parathyroid hormone (PTH) and calcitonin, regulate the
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International Journal of Applied Dental Sciences  
 

during the later stages of the pregnancy. Role of professionals

Radiographic imaging such as a panoramic film and periapical For successful completion of orthodontic treatment, a good
films are routinely used to assess periodontal health and root communication must be established between the patient and
inclinations. According to American Dental Association the orthodontist from the beginning. Detailed history, oral
(ADA), every precaution should be taken to minimize examination and assessment of patient compliance and
radiation during pregnancy. However, if there is an acute expectations will enable the orthodontist to develop practical
dental infection, it must be addressed and radiographs can be goals for successful treatment. It is important for orthodontists
taken. In addition, the radiation caused by oral radiography is to be aware of the limitations that may be inherent in such
minimal. It is advisable to coordinate the orthodontic treatment cases. In addition to reinforcing oral hygiene, it is important
plan with the obstetric care provider to establish guidelines that the patient be sent for professional cleaning at regular
that will beneficial for maternal oral health and perinatal intervals. Good communication among health-care
outcomes. Orthodontic treatment could include the necessity to professionals will benefit the patient and improve their quality-
have one of the teeth extracted. Tooth extraction by itself may of-life. We should use steel ligature in place of elastic modules
not be dangerous for a pregnant woman. However, one must because elastic modules are less hygienic [20].
avoid taking X-rays during the first trimester of pregnancy. In However, there are no obvious contraindications to
fact, it’s better to avoid X-rays for the entire duration of orthodontic therapy in a healthy pregnant patient. However, it
pregnancy. If a lady patient is up for a radiograph and suspect may be advisable to limit the visits to shorter appointments to
she could possibly be pregnant, it's advisable to wait till you avoid the patient being in extreme supine position especially
confirm this before you go ahead and get an X-ray done [18]. during the later stages of pregnancy. Radiographic imaging
such as a panoramic film and peri- apical films are routinely
Orthodontic treatment plan used to assess periodontal health and root inclinations. Every
It is of very importance to plan a very simple and realistic precaution should be taken to minimize radiation during
treatment plan in patients who are pregnant. A good pregnancy. However, if there is an acute dental infection, it
communication between the orthodontist and the patient is a must be addressed and radiographs can be taken. In addition,
key for successful results. If the patient wants to undergo the radiation caused by oral radiography is minimal. It is
orthodontic therapy primarily for frontal aesthetics and is not advisable to coordinate the orthodontic treatment plan with the
willing to be compliant for a 2-year treatment plan and obstetric care provider to establish guidelines that will benefit
comprehensive therapy, this needs to be established at the maternal oral health and perinatal outcomes.
beginning. In such patients, limited treatment should only be
performed. As an alternative in some patients, it may be Role of patients
advisable to wait until after the pregnancy to start orthodontic It is important for women to be aware of the importance of
treatment [19]. oral health-care especially during pregnancy. We have
therefore described in detail the known associations between
Oral hygiene maintenance during orthodontic treatment periodontal disease and complications during pregnancy.
Before starting orthodontic treatment, any pre-existing Simple and effective home care measures described earlier and
periodontal condition must be checked. Because of pre- professional dental care will enable women to prevent any
existing hormonal changes during pregnancy, the gingival gingival and/or periodontal issues during the course of their
tissues may be already inflamed in pregnancy women. Thus, a orthodontic treatment [21]. It is important to emphasize that
more rigorous oral hygiene routine will be required to maintain professional tooth cleaning alone is not sufficient for
optimal oral health. Frequent dental prophylaxis will be preventing gingival and periodontal issues and conscientious
helpful and meticulous home- care regimens will need to be oral home care is also of paramount importance.
employed to ensure success. In addition to tooth brushing, a
detailed instruction in the manipulation of dental floss will Patient education and awareness
enable the patient to floss when the braces are in the mouth. It is important that medical professionals dealing with prenatal
Many interdental cleaning aids such as tooth picks or care be educated the importance of dental care to their patients.
miniature bottle brushes can be attached to handles for the In addition, the dental health-care providers must be aware of
convenience of manipulation around teeth, Thus oral hygiene the importance of dental care during pregnancy and effects of
regimen maintained at home and coupled with professional poor periodontal health on pregnancy and the baby. Various
dental cleaning will ensure successful oral health and keep behavioral modification techniques could be employed.
orthodontic patients during pregnancy free of gingival and Constant motivation of the patient could help improve patient
periodontal disease during active treatment [4]., compliance during orthodontic treatment [22]. It is important to
Orthodontic treatment during pregnancy emphasize that professional tooth cleaning alone is not
sufficient for preventing gingival and periodontal issues and
conscientious oral home care is also of paramount importance.
Thus, a combination of professional tooth cleaning and
educational reinforcement of oral hygiene will prove to be
successful.
Constant motivation of the patient could help improve patient
compliance during orthodontic treatment. It is critical for the
dental care provider to focus on changing the individual’s
perceived need towards oral health and or values associated.
Especially during orthodontic treatment, which is over a period
of a couple of years, constant reinforcement and periodic
monitoring and occasional discussions with the patient are
extremely crucial. Most importantly, there needs to be a

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psychological change and motivation in the patient that will 15. Kale S, Kocadereli I, Atila P, Asan E. Comparison of the
make them conscious about their oral hygiene status. effects of 1,25 –dehydroxycholecalciferol and
prostaglandin E2 on orthodontic tooth movement. Am J
Conclusion Orthod. 2004; 125:607-14.
It has been found that orthodontic treatment during pregnancy 16. Kawakami M, Takamo-Yamamoto T. Local injection of
may aggravate gingivitis caused by local and systemic factors. 1,25-dihydroxyvitamin D3 enhanced bone formation for
Periodontitis during pregnancy may lead to complications and tooth stabilization after experimental tooth movements in
preterm low-birth-weight babies. Awareness among oral and rats. J of Bone and Mineral Metabolism. 2004; 22:541-6.
prenatal healthcare professionals is critical for optimal patient 17. Hartridge T, Illing H M, Sandy J R. Role of folic acid in
care. For successful completion of orthodontic treatment, a oral clefting. British Journal of Orthodontics 1999;
good communication must be established between the patient 26:115-120.
and the orthodontist from the beginning. Detailed history, oral 18. Muralidhar Mupparapu. Radiation protection guidelines
examination and assessment of patient compliance and for the practicing orthodontist. Am J Orthod Dentofacial
expectations will enable the orthodontist to develop practical Orthop 2005;128:168-72
goals for successful treatment. It is important for orthodontists 19. Michalowicz BS, DiAngelis AJ, Novak MJ et al.
to be aware of the limitations that may be inherent in such Examining the safety of dental treatment in pregnant
cases. In addition to reinforcing oral hygiene, it is important women. J Am Dent Assoc 2008; 139:685-695.
that the patient be sent for professional cleaning at regular 20. Avesh Sachan, Vinay Kumar Verma, Sujit Panda, Karuna
intervals. Good communication among healthcare Singh. Journal of Orthodontic Research, Sep-Dec 2013,
professionals will benefit the patient and improve their quality 1(3).
of life. 21. Gupta k et al. Orthodontic treatment consideration in
pregnancy: an insight. Jounal of orofacial research, april-
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