PericoronitisAugSept09_2

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Per icor onitis

Per icor onitis is defined as in flammation in

the soft tissues surr ounding the cr own of a

par tially erupted tooth. It generally does not

ar ise in teeth that erupt normally; usually, it

is seen in teeth that erupt ver y slowly or

become impacted, and it most commonly

a ffects the lower thir d molar . Once the

follicle of the tooth communicates with the

ora

l ca

vity, it is thou

ght tha

t ba

cter

ia

l in

gr

essinto the follicular space initiates the in fection.

Severa l studies have shown that the

micr oflora of per icor onitis ar e pr edominantly

anaer obic.1,2,3,4,5,6 It is generally agr eed that

this pr ocess is potentiated by food debr is

accumulating in the vicinity of the

oper culum and occlusal trauma of the

per icor onal tissues by the opposing tooth.

Clinically, per icor onitis can be acute or

chr onic. The acute form is character ised by

sever e pain, often r eferr ed to adjacent ar eas,

causing loss of sleep, swelling of the

per icor onal tissues, dischar ge of pus, tr ismus,

r egiona l lymphadenop athy, pa in on

swallowing, pyr exia, and in some cases

spr ead of the in fection to adjacent tissue

spaces. Patients with chr onic per icor onitis

complain of a dull pain or mild discom for t

lasting a da y or two, with r emission lasting

man y months. They ma y also complain of a

bad taste. Pr egnancy and f atigue ar e

associated with an incr eased occurr ence of

per icor onitis.

Bilateral per icor onitis is rar e and str ongly

suggests unde r ly ing in fe ct iousmononucleosis. In a study by Nitzan et al

(1985) r eviewing the clinical aspects of

per icor onitis, f r om a sample of 245, the

highest incidence of per icor onitis was found

in the 20-29 year age gr oup (81%).1 The

condition was rar ely seen befor e 20 or a fter

40. The general health of the patient was not

found to be a pr edisposing f actor , other than

upper r espirator y tract in fection, which

pr eceded the occurr ence of the disease in

43% of cases. Emotional str ess pr eceding the

manifestation of per icor onitis was r epor ted

in

66% of the sam

ple. Ther

e wa

sa

lsoa

significant corr elation between oral hygiene

and the sever ity of the condition. The acute

form tended to appear in cases of moderate

or poor oral hygiene, while the chr onic type

was associated with good or moderate

hygiene. Ther e was no significant differ ence

between the sexes. A seasonal var iation was

noted, the peak incidences occurr ing in June

and December . In 67% of the cases the

involved tooth was classified as ver tical, in

12% as mesio-angular , in 14% as disto-

angular , and var ious other positions

r epr esented 7%.

Tr eatment

For patients pr esenting with localised pain

and swelling involving the per icor ona l

tissues, and in the absence of r egional and

systemic symptoms, it is r ecommended that

local measur es only ar e used. These include

debr idement of plaque and food debr is,

drainage of pus, irr igation with ster ile saline,

chlor hexidine or hydr ogen per oxide, and

elimination of occlusal trauma. In the past

the use of caustic agents such as chr omicacid, phenol liquef actum, tr ichlor oacetic acid

or Howe’s ammoniaca l soluti on was

advocated to contr ol pain by placing a small

Justin Moloney BDentSc, MFD RCSI

SHO in Oral Sur ger y

Dublin Dental Hospital

Lincoln Place

Dublin 2

Leo F.A. Stassen FRCS(Ed), FDS

RCS, MA, FTCD, FFSEM(UK), FFD RCSI

Pr ofessor of Oral and Maxillof acial Sur ger y

Dublin Dental School and HospitalLincoln Place

Dublin 2

Email: [email protected]

Pericoronitis: treatmentand a clinical dilemma

Pericoronitis is an infection associated with impacted lower third molars that can

necessitate the removal of these teeth. The clinical features of this condition are

described and its treatment outlined, emphasising local measures. A case of

pericoronitis in a 52-year-old patient is discussed, which illustrates the risks and

benefits of removal of wisdom teeth; removal can lead to nerve damage, retention

can precipitate serious, even life-threatening infection.

Journal of the Irish Dental Association 2009 ; 55 (4): 190 – 192

SCIENTIFIC

190 Volume 55 (3) : June/July 2009

Journal of the Irish Dental Association



amount on a cotton pledget under the oper culum. The r esultant

chemical cauter isation of the pain ner ve endings in the super ficial

tissues gave rapid pain r elief; however , the use of these toxic

chemicals in the oral cavity is no longer encouraged. Ozone has been

pu

t for

war

da

sa

loca

lan

tim

icr

obia

l tha

tm

ight bea

u

sef u

la

djun

ct in

the tr eatment of per icor onitis; however , ther e is no r esear ch available

to show its efficacy as yet.

In addition to local pain and swelling, if the patient is exhibiting

r egional or systemic signs and symptoms, antimicr obial therapy is

r ecommended; however , it should be emphasised that it is as an

adjunct rather than a fir st-line tr eatment. Systemic symptoms include

pyr exia, tachycar dia and hypotension. The antibiotic of choice is

either metr onidazole 400mg thr ee times a da y for five da ys or

phenoxymethylpenicillin 500mg four times a da y for five da ys. The

two can be used in combination for sever e in fections. For patients

who ar e aller gic to penicillin, er ythr om ycin 500mg four times a da y

for five da ys is suitable. These ar e all active against anaer obic bacter ia,

which ar e the pr edominant cultivable micr oflora found in per icor onitis

and ar e the fir st-line antibiotics of choice. Once the acute phase of this

condition has passed, oper culectom y has been used as a pr eventive

measur e; however , ther e is no r esear ch to suppor t or condemn this

mode of tr eatment.

Case study

This case is an illustration of the clinical dilemma that clinicians ar e

f aced with when tr eatment planning for lower thir d molar s.

A 52-year -old female patient pr esented for r eview in the Oral and

Maxillof acial Depar tment in ear ly 2008. Or iginally she had been

r eferr ed by her general dental practitioner having su ffer ed two

episodes of per icor onitis r equir ing antibiotics involving the lower r ightthir d molar in 2006, thus f ulfilling the National Institute of Clinical

Excellence guidelines for the extraction of thir d molar s.9 The

antibiotics used wer e not stated by the r eferr ing dentist. She was

assessed in clinic in Januar y 2007. On examination at that time her

lower r ight thir d molar was found to be par tially erupted, buccally

placed, and with no signs of pr evious in fection in the per icor onal

tissues. Radiographic examination showed that the tooth was slightly

disto-an

gu

lar

, below bu

t close to the occlu

sa

l plan

e, witha

con

ica

lr oot, which was closely r elated to the upper bor der of the in fer ior

alveolar ner ve canal (Figure 1). Ther e was no per iodontal bone

destruction, nor was ther e rar efying osteitis distal to the cr own of the

tooth, indicative of chr onic in fection.

On the basis that this tooth had given r ise to two r ecent in fections, the

decision was taken to extract this tooth under local anaesthetic on a

dento-alveolar sur ger y list and she was put on the waiting list, which

was at the time ar ound 10 months. She was scheduled to have the

tooth r emoved in November 2007, but at the last minute cancelled

the appointment and r equested a f ur ther clinical r eview on the basis

that she had had no symptoms in over a year and was concerned

about the possibility of ner ve damage as a r esult of the pr ocedur e. She

had been given the usual warnings about the possibility of damage to

the in fer ior alveolar and lingual ner ves, and in her case that the apex

of her thir d molar was in close pr oximity to the upper bor der of the

in fer ior alveolar ner ve canal.

On r eview in 2008, clinically and radiographically both the lower r ight

thir d and second molar s wer e f r ee of pathology. The tissues ar ound

the thir d molar appear ed healthy, as can be seen in Figure 2.

After a discussion with the patient it was decided not to extract it on

the basis that it was now f r ee of pathology and the patient did not

want to r isk an y long-term mor bidity unless the extraction was

absolutely necessar y. It was not possible to give this patient definitive

advice as to whether or not this tooth would give tr ouble in the f utur e.

Discussion

Mer cier and Pr ecious (1992) r eviewed the literatur e in terms of the

r isks and benefits of thir d molar sur ger y under the headings of: r isks

SCIENTIFIC

Volume 55 (4) : August/September 2009 191


FIGURE 1: Radiographic examination of the tooth in January 2007. FIGURE 2: Review of the patient in 2008.



of non-inter vention ver sus inter vention; and, benefits of non-

inter vention ver sus inter vention (Table 1).7

They conclude that absolute indications and contra-indications for the

r emoval of asymptomatic thir d molar s cannot be established as no

long-term studies exist to validate either ear ly r emoval or deliberate

r etention of these teeth. The National Institute of Clinical Excellence in

the UK has adopted the following guidelines for clinical practice in the

National Health Ser vice:8

1. The practice of pr ophylactic r emoval of pathology-f r ee impacted

thir d molar s should be discontinued in the NHS.

2. The standar d r outine pr ogramme of dental car e by dental

practitioner s and/or parapr ofessional sta ff need be no differ ent, in

general, for pathology-f r ee impacted thir d molar s (those r equir ingno additional investigations or pr ocedur es).

3. Sur gical r emoval of impacted thir d molar s should be limited to

patients with evidence of pathology. Such pathology includes

unr estorable car ies, non-tr eatable pulpal and/or per iapical

pathology, cellulitis, abscess and osteom yelitis, internal/external

r esor ption of the tooth or adjacent teeth, f ractur e of tooth, disease

of follicle including cyst/tumour , tooth/teeth impeding sur ger y or

r econstructive jaw sur ger y, and when a tooth is involved in or within

the field of tumour r esection.

4. Specific attention is drawn to plaque formation and per icor onitis.

Plaque formation is a r isk f actor but is not in itself an indication for

sur

ger

y. The degr

ee to which the sever

ity or

r

ecurr

en

cera

te of per icor onitis should in fluence the decision for sur gical r emoval of a

thir d molar r emains unclear . The evidence suggests that a fir st

episode of per icor onitis, unless par ticular ly sever e, should not be

consider ed an indication for sur ger y. Second or subsequent episodes

should be consider ed the appr opr iate indication for sur ger y.

This lower r ight thir d molar has been par tially erupted for at least 20

year s (the patient cannot r ecall beyond that) and was associated with

two episodes of in fection that had completely r esolved. Par t of the

r eason for this ma y be the patient’s good plaque contr ol, but other

than this, it is difficult to explain why the per icor onal tissues have not

become chr onically in fected as happens ar ound so man y par tially

erupted thir d molar s, and it is impossible to give a clear pr ognosis.

This demonstrates the dilemma clinicians f ace when advising patients.

If the tooth is not r emoved, ther e is a r isk of the development of a

ser ious in fection that sometimes r equir es hospitalisation and can even

be life thr eatening, for example if the in fection spr eads to the sub-

mandibular and sublingual spaces (Ludwig’s angina) or the

paraphar yngeal space (paraphar yngeal abscess). Ludwig’s angina

pr esents with pyr exia and malaise, elevation of the tongue and floor

of mouth, difficulty swallowing, slurr ed speech and boar d like swelling

of the submandibular tissues, eventually involving the anter ior neck.

Paraphar yngeal abscess pr esents with considerable pyr exia and

malaise, extr eme pain on swallowing, dyspnoea and deviation of the

lar ynx to one side. These conditions warrant ur gent sur gical

inter vention to secur e the air wa y and to drain and decompr ess thea ffected tissue spaces.

If the tooth is r emoved, ther e is the r isk of major permanent

outcomes, especially that the patient could be left with permanent

anaesthesia, paraesthesia or dysaesthesia a ffecting her lower lip or

tongue. This case study illustrates the need for in formed valid consent

and the need for the clinician and patient to balance the r isk–benefit

analysis for their sur gical pr ocedur e.

Refer ences

1. Nitzan, D.W., Tal, O., Sela, M.N., Shteyer, A. Per icor onitis: a

r eappraisal of its clinical micr obiologic aspects. J Oral Maxillofac Surg 1985;

43 (4): 510-516.

2. Moloney, J., Stassen, L.F. The r elationship between per icor onitis,

wisdom teeth, putative per iodontal pathogens and the host r esponse. J Ir

Dent Assoc 2008; 54 (3): 134-137.

3. Hurlen, B., Olsen, I. A scanning electr on micr oscopic study on the

micr oflora of chr onic per icor onitis of lower thir d molar s. Oral Surg Oral Med

Oral Pathol 1984; 58 (5); 522-532.

4. Weinberg, A., Nitzan, D.W., Shetyer, A., Sela, M.N. In flammator y

cells and bacter ia in per icor onal exudates f r om acute per icor onitis. Int J Oral

Maxillofac Surg 1986; 15 (5): 606-613.

5. Mombelli, A., Buser, D., Lang, N.P., Berthold, H. Suspected

per iodontopathogens in erupting thir d molar sites in per idontally healthy

individuals. J Clin Periodontol 1990; 17 (1): 48-54.

6. Wade, W.G., Gray, A.R., Absi, E.G., Barker, G.R. Pr edominant

cultivable flora in per icor onitis. Oral Microbiol Immunol 1991; 6 (5); 310-

312.

7. Mercier, P., Precious, D. Risks and benefits of r emoval of impacted thir dmolar s. A cr itical r eview of the literatur e. Int J Oral Maxillofac Surg 1992; 21

(1): 17-27.

8. www.nice.or g.uk/guidance/index.jsp?action=byID&o=11385.

SCIENTIFIC

192 Volume 55 (4) : August/September 2009


Non-inter vention

■ Cr owding of dentition

based on gr owth

pr ediction.

■ Resor ption of adjacent

tooth and per iodontal

status.

■ Development of

pathological conditions

such as in fection, cyst,

tumour .

■ Avoidance of r isk.

■ Pr eser vation of

f unctional teeth.

■ Pr eser vation of r esidual

r idge.

Inter vention

■ Minor transient: sensor y

ner ve alteration,

alveolitis, tr ismus and

in fection.

■ Haemorr hage.

Dentoalveolar f ractur e

and displacement of

tooth.

■ Minor permanent:

per iodontal injur y,

adjacent tooth injur y,TMJ injur y.

■ Major permanent:

alter ed sensation, vital

or gan in fection, f ractur e

of mandible.

■ Litigation.

■ In r elation to age, i.e.,

less mor bidity post op

in younger patients.

■ In r elation to differ ent

therapeutic measur es.

Table 1: Risks and benefits of thir d molar surger y

Risks of

Benefits of



FACT FILE



Or thodontic tr eatment benefits man y of our child patients. It can

sometimes be difficult to know what to be concerned about and when

ma y be the most appr opr iate time to r efer a child to a specialist for

or thodontic tr eatment, or for advice with r egar d to management or

inter ception for a younger child.1

Pr imar y dentition

It is rar e for or thodontic tr eatment to be indicated in the pr imar y

dentition, but this stage is f undamental in establishing the dentition

and in establishing the dental health r equir ed for f utur e or thodontic

tr eatment.

Identifying orthodontic problemsDR CIARA SCOTT and DR SHEILA HAGAN present a guide for the busy practitioner in examining the developing dentition and

deciding when to intervene and when to refer.

FIGURE 1a: Poor oral hygiene will compromise

suitability for orthodontic treatment.

FIGURE 1b: Decalcification of the occlusal

surfaces has occurred as a result of fizzy

drinks while wearing a removable appliance.

FIGURE 2: Severe crowding as a consequence

of tooth decay and early primary extractions.

PROBLEM

Dental health

(Figures 1a and 1b)

Teeth pr esent

Anomalies

Ear ly loss of pr imar y

teeth (Figure 2)

Spacing and cr owding

INTERVENTION

Developing good habits f r om an ear ly age can

help to avoid some or thodontic pr oblems. Ear ly

loss of pr imar y teeth due to car ies can cause

localisation of cr owding and contr ibute to

malocclusion. Poor motivation and dental

anxiety can compr omise or thodontic

tr eatment.2

When examining a child for the fir st time, a

histor y is established f r om the par ent for an y

missing teeth.

Occasionally, pr imar y teeth ar e congenitally

missing, impacted or in f raoccluded. They ma y

displace permanent successor s.

Sometimes gemination, f usion, hypodontia or

supernumerar y teeth can occur in the pr imar y

dentition.

Pain, trauma, deca y or in fections take pr ior ity in

the young child. If a tooth has to be lost or

extracted, an y consequent or thodontic pr oblem

has to be dealt with as a secondar y pr oblem at

a later date.

The pr imar y dentition is best spaced. Cr owding

is mor e likely in the permanent dentition if ther e

is cr owding in the pr imar y dentition.

REASONING

Ear ly loss of pr imar y teeth can cause cr owding and

cr ossbites due to ar ch contraction.2 Pr evention of dental

disease and maintenance of an intact pr imar y dentition can

simplify or thodontic tr eatment later . Or thodontics will be

mor e efficient and mor e successf ul in a well motivated

patient with a car ies-f r ee and well maintained dentition. It is

impor tant that patients and their par ents under stand this.

Contralateral teeth usually erupt within six months of each

other .

Radiographs ma y be indicated if an unusual sequence of

eruption is identified. Congenitally missing pr imar y teeth ma y

be associated with a syndr ome, so f ull medical histor y should

be taken and the patient r eferr ed to a paediatr ic dentist.

Usually, no inter vention is r equir ed unless the teeth ar e

pr eventing eruption of permanent teeth. It is likely that

ther e ma y be missing or supernumerar y permanent teeth if

anomalies ar e pr esent in the pr imar y dentition, so par ents

can be warned of this possibility.

Unless co-operation and oral hygiene ar e excellent, space

maintainer s ar e not usually suitable for ver y young childr en.

It is impor tant to establish and maintain good oral health

f r om a young age.

Advise par ent, but no tr eatment indicated.



FACT FILE



FEATURE

Unerupted incisor

(Figure 3)

Unerupted/impacted

molar (Figure 4, 4a

and 4b)

INTERVENTION

Look for and palpate for the permanent tooth

fir st. Disruption in the normal sequence of

eruption ma y warrant f ur ther investigation. Take

radiograph (occlusal view anter ior maxilla or

per iapical) to locate the unerupted tooth if it

has been mor e than six months since

contralateral tooth erupted.3 Ask about an y

histor y of trauma and at what age this occurr ed.

Look for an y dilaceration or supernumerar ies on

the film.

A permanent molar ma y become impacted

against the pr imar y molar . It ma y self-r esolve

but inter vention is indicated if mor e than six

months has elapsed since the contralateral tooth

erupted. Tr eatment can involve: using an

or thodontic separator to disimpact, or r eduction

of the distal aspect of the pr imar y second molar .

Extraction of E is indicated if disimpaction is not

successf ul.

REASONING

Refer , as soon as the pr oblem is identified, with the

radiograph if you have taken one.

The patient is likely to benefit f r om extraction of the

pr imar y incisor if this is pr esent.

The or thodontic plan would usually involve r emoval of an y

supernumerar y teeth and sur gical exposur e of the

unerupted incisor . Or thodontic traction/tr eatment ma y not

be r equir ed if ther e is su fficient space for the tooth to

erupt, so consider maintaining space if appr opr iate.

A fixed or r emovable or thodontic appliance can be used to

align the tooth.

Refer for inter vention tr eatment or for advice with r egar d

to extraction of the pr imar y second molar . The 6 will erupt

mor e mesially if the E is extracted causing space loss. This

can be managed later . When r educing the distal aspect of

the E, a blunt ended diamond ma y be used, and car e is

needed to avoid iatr ogenic damage to 6. Pr imar y or

secondar y f ailur e of eruption of permanent molar s can

occur . The pr ognosis of these molar s ma y be poor , but

inter vention is r equir ed to r educe the r isk of mor e distal

teeth being a ffected. These should be r eferr ed.4

FIGURE 3: An uneruped central incisor; the

sequence is disrupted as the U2s have

erupted.

FIGURE 4: An impacted upper right first

permanent molar.

FIGURE 4b: An orthodontic separator is

placed in the contact point. Specialists may

progressively tighten a brass wire separator.

FIGURE 4a: An impacted upper right first

molar.

FIGURE 5: An anterior crossbite with

mandibular displacement off LL1. There is

some gingival dehiscence and mobility of this

tooth.

The mixed dentition

This is the stage when the occlusion is

star ting to establish. Most childr en will

benefit f r om a f ull or thodontic examination

by their general practitioner at the age of 10.



FACT FILE



FEATURE

Cr ossbites

(Figures 5, 6 and 7)

Over jet (Figure 8)

Over bite

(Figures 9 and 10)

INTERVENTION

When an anter ior or unilateral poster ior

cr ossbite occur s, ther e is often a mandibular

displacement pr esent.

Indications for ear ly corr ection of cr ossbites ar e:

■ mandibular displacement, for war d or laterally

f r om RCP;

■ wear f acet/trauma to a tooth in cr ossbite;

■ dehiscence or trauma to the gingivae; and,

■ mobility of the teeth.

Mandibular displacements ma y pr ecede TMD. If

RCP develops in a displaced position, then

inter ceptive or thodontic tr eatment is indicated

to establish good occlusal development.

It has been shown that ther e is an incr eased r isk

of incisor trauma in childr en with an over jet

>6mm. Incr eased over jets ar e usually most

ideally tr eated in the late mixed dentition.

Check for an y trauma or str ipping of the lower

labial or upper palatal gingivae.

An over bite is ver y deep if ther e is no lower

incisor show in occlusion.

Over jets, over bites and skeletal dispr opor tion ar emuch mor e simply tr eated in the gr owing

patient, and most efficiently tr eated in the late

mixed dentition.

REASONING

Refer for opinion/tr eatment.

Studies have suggested that ear ly corr ection of cr ossbites

can pr event the cr ossbite being per petuated into the

permanent dentition.5

This ma y be achieved with occlusal

gr inding of pr imar y teeth or a r emovable or fixed

appliance.

Ear ly inter ceptive tr eatment r elies on the child’s co-

operation and good oral hygiene, so tr eatment ma y be

postponed if this is poor . Pr imar y teeth have poor

under cuts so r etention of a URA ma y be mor e difficult in

the ear ly mixed dentition, especially if teeth ar e due to

exfoliate.

Refer with view to f unctional appliance tr eatment. This is

most efficient a fter the fir st pr emolar s have erupted. Ear ly

tr eatment ma y be indicated if sever e OJ and r isk of trauma,

or if the child is being teased. Use mouth guar d for bicycle

and contact spor ts to aid pr evention of incisor trauma.

Ear ly r eferral is indicated if gingival trauma is obser ved.

Inter ceptive management with a bite plane ma y be

indicated. Deep over bites ma y deepen and become

traumatic with gr owth. Tr eatment of deep or traumatic

over bites is much mor e complex in a non-gr owing patient6

(Figure 11).

FIGURE 6: UR1 is in crossbite with LR1; the

unseen UR2 is also in crossbite with the

instanding LR2.

FIGURE 7: The mandibular displacement off

the instanding UR2 has caused labial gingival

dehiscence and mobility LR1.

FIGURE 8: The overjet is 12mm and there is a

full unit Cl II molar relationship.

FIGURE 9: Increased and complete overbite.

There is trauma to the lower labial gingivae.

FIGURE 10: A simple URA with active flat

anterior bite plane, to allow the lower molars

to erupt and therefore reduce the overbite.

FIGURE 11: Un-erupted and non-palpable

UL3 in the permanent dentition.



FACT FILE



FEATURE

Poor pr ognosis of

teeth (esp. 6s)

Unerupted canines

(Figures 11 and 12)

Class III (Figure 13)

INTERVENTION

Timing of fir st molar extractions can be crucial.

It can simplify or thodontic tr eatment later or

even r educe the need for or thodontics.

Compensating and balancing extractions ar e

not alwa ys appr opr iate, especially if the child

will co-operate with or thodontic tr eatment later .

Canines ar e usually palpable in the buccal sulcus

by nine-and-a-half year s, and ther e should be a

buccal pr ominence by the time the 4s have

erupted. They should erupt within six months of

the contralateral tooth having erupted. Palpate

buccally and palatally and check for mobility of

Cs. Also look for distobuccal flar ing of 2s.

Unlike Class II cases, Class III pr oblems ar e less

successf ully inter cepted in gr owing patients.

REASONING

Refer for opinion.

Resolving acute pain and in fection is paramount. Ideally,

extractions can be planned in conjunction with

or thodontics. Check for the pr esence of 5s and 8s pr ior to

planning extractions.

Obtain parallax shift radiographs: ver tical (OPG and

maxillar y occlusal); or , hor izontal (2x per iapical or maxillar y

occlusal). Extracting Cs (between 10-13 year s of age) ma y

help the 3s to erupt or impr ove position if ther e is

su fficient space in the ar ch.7

Refer for an or thodontic opinion about extracting Cs in

cr owded cases or if canine is ver y high, ver y mesial or looks

un f avourable radiographically. If 3s ar e in a f avourable

position, they should erupt within 6-12 months of the C’s

extraction.

Refer for an opinion.

Ear ly tr eatment of Class III cases is most successf ul in low

angle/deep bite cases, in patients who have a mandibular

displacement and can achieve an edge to edge bite.

Obser vation ma y be appr opr iate. Tr eatment ma y be bycamou flage or sur ger y later depending on patients’

concerns. A definitive tr eatment plan ma y not be finalised

until late teens when most gr owth is completed.

FIGURE 12: This 13-year-old patient is in the

permanent dentition, with 7s erupted, but the

ULC is firm with no buccal prominence. The

lateral incisor is flared.

FIGURE 13: Cl III malocclusion; this is a

postural Cl III maloccusion as the patient can

achieve edge to edge and is displacing

forward.

FIGURE 14: A simple URA with a hyrax screw

and posterior bite planes to allow correction

of the crossbites and displacement.

FIGURE 15: Skeletal discrepancy in this high

angle Cl III patient.

FIGURE 16a: Infraocclusion of the primary

second molars.

FIGURE 16b: The permanent successors are

present.



FACT FILE



FEATURE

Skeletal discr epancies

(Figure 14 and 15)

In f raocclusion

(Figures 16a, 16b,

17aan

d 17b)

Retained/missing teeth

Cr owding (Figure 18)

INTERVENTION

A skeletal discr epancy can occur in all thr ee

dimensions. Anter o-poster ior (class II and III),

transver se (asymmetr y) or ver tical (deep or open

bite tendency). A mandibular displacement can

cause an asymmetr y or exaggerate a skeletal

pr oblem but this is not a true skeletal

asymmetr y.

The second pr imar y molar s ar e most commonly

a ffected. It can be sever e if it occur s in a young

childan

da

ffects Dsan

d Es. An

OPGma

y beindicated to check for the pr esence and position

of the permanent successor teeth.

If you suspect/diagnose hypodontia in a child

of an y age then a thor ough histor y including

f amily histor y is indicated. Ther e can be a wide

var iation of normal occlusal development.

Check if the sequence of eruption is disrupted.

Excellent oral health, pr eser vation of pr imar y

teeth and pr evention of deca y and f ur ther

tooth loss is essential for patients with

hypodontia. Pr imar y molar s should be r estor ed

and maintained until a definitive plan is in

place.

Assess for cr owding and spacing at ar ound the

age of 10 in the mixed dentition. On average,

21mm of space is r equir ed in the lower ar ch

between the lateral incisor and the fir st molar to

accommodate the canines and pr emolar s, and

22mm in the upper ar ch.

REASONING

Refer for opinion ear ly. Patients with sever e skeletal

discr epancy benefit f r om joint or thodontic and sur gical

planning. The optimal tr eatment for sever e skeletal

pr oblems is usually or thognathic sur ger y, but other

tr eatment options ma y be indicated.

Refer for or thodontic/paediatr ic opinion.

Management depends on age, site and sever ity.

If the tooth becom

es in

f ra

occlu

ded ver

y ear

ly or

is belowthe contact point, extraction is mor e likely to be

indicated. If a permanent successor is pr esent, the

in f raoccluded tooth should exfoliate, but this ma y be

dela yed.8

Refer for specialist opinion.

These patients benefit f r om joint or thodontic and

r estorative planning. The or thodontic plan will depend on

the site and sever ity of hypodontia and the overall

malocclusion. Often pr imar y molar s can be pr eser ved for a

long time if the permanent successor s ar e missing.8 If they

become in f raoccluded, they ma y need to be extracted as

this can compr omise the alveolar bone and per iodontal

tissues. Hypodontia and in f raocclusion ar e associated with

an incr eased r isk of impacted canines.9

Refer for an or thodontic assessment. At this mixed

dentition stage, it is possible to:

1. Inter cept with extractions to allow blocked out teeth to

dr op into place.

2. Fit an appliance, such as a lingual ar ch, to maintain

space or utilise leewa y space.

3. Fit active appliances to expand the ar ch or distalise the

molar s to open space for cr owded teeth.

Once the occlusion is established and teeth ar e blocked

out, it is mor e difficult to accommodate them withoutextractions.

FIGURE 18: A lower lingual arch can act as a

space maintainer or to utilise leeway spaces.

FIGURE 17b: Infraocclusion, hypodontia and

ectopic canines can be related. This patient will

benefit from extraction of the upper Cs and Ds

and specialist review of occlusal development.

FIGURE 17a: Infraocclusion of the primary

first molars associated with missing upper

lateral incisors and palatal upper canines.



When r eferr ing patients for an or thodontic opinion, it is helpf ul if the

r

eferra

l con

ta

in

s the pa

tien

t’snam

e,a

ge,an

dan

yr

elevan

tm

edica

l,dental and social histor y. Also include details of an y specific concern

you have. Please for war d an y r ecent radiographs. It is also helpf ul to

make it clear if you feel the case is ur gent. Or thodontists ma y give an

opinion based on a photograph or radiograph. Full clinical

examination does give a mor e compr ehensive assessment of the

or thodontic needs.

The general practitioner is r esponsible for monitor ing the developing

dentition, pr omoting pr evention and identifying potential pr oblems as

they ar ise. A good wor king knowledge of the Index of Tr eatment Need

IOTN10

can help to identify the most sever e pr oblems and identify

those patients who ma y be eligible for tr eatment within the HSE

or thodontic ser vice.

Access to or thodontic tr eatment within the HSE is by r eferral by the

HSE public dental ser vice and the pr incipal dental sur geon for each

ar ea.

2007 HSE Guidelines11

Gr ade 5 Tr eatment r equir ed

5.a Incr eased over jet >9mm

5.h Extensive hypodontia with r estorative implications (mor e than

one tooth missing in an y quadrant r equir ing pr e-r estorative

or thodontics). Amelogenesis imper fecta and other dental

anomalies which r equir e pr e-pr osthetic or thodontic car e.

5.i Impeded eruption of teeth (apar t f r om 3r d molar s) due to

cr owding, displacement, the pr esence of supernumerar y teeth,r etained deciduous teeth, and an y pathological cause

5.m Rever se over jet >3.5mm with r epor ted masticator y and speech

difficulties

5.p Defects of cleft lip and palate

5.s Su

bm

er

ged decidu

ou

s teeth –arran

ger

em

ova

l of teeth bu

tor thodontic tr eatment not necessar ily pr ovided

Gr ade 4 Tr eatment r equir ed

4.b Rever se over jet >3.5mm with no masticator y or speech difficulties

4.c Anter ior or poster ior cr ossbites with >2mm discr epancy between

the r etruded contact position and inter cuspal position

4.d Sever e displacements of teeth >4mm but only with Aesthetic

Component of Figures 20-22 .

4.e Extr eme lateral or anter ior open bites >4mm

4.f Incr eased and complete over bite with gingival or palatal trauma

4.l Poster ior lingual cr ossbite with no f unctional occlusal contact in

one or mor e buccal segments

4.m Rever se over jet >1mm but <3.5mm with r ecor ded masticator y

and speech difficulties

Refer ences

1. O’Brien, K., McComb, J.L., Fox, N., Bearn, D., Wright, J. Do

dentists r efer or thodontic patients inappr opr iately? Br Dent J 1996; 181

(4): 132-136.

2. Melsen, B., Terp, S. The in fluence of extractions car ies cause on the

development of malocclusion and need for or thodontic tr eatment. Swed

Dent J Suppl 1982; 15: 163-169.

3. Huber, K.L., Suri, L., Taneja, P. Eruption distur bances of the maxillar yincisor s: a literatur e r eview. J Clin Pediatr Dent 2008; 32 (3): 221-230.

4. Kurol, J., Bjerklin, K. Ectopic eruption of maxillar y fir st permanent

molar s: a r eview. ASDC J Dent Child 1986; 53 (3): 209-214.

FACT FILE



FEATURE

Retained pr imar y teeth

(Figure 19)

INTERVENTION

Over -r etained pr imar y teeth, which f ail to

exfoliate when the permanent teeth ar e

erupting, can cr eate plaque traps and can cause

deflection of the permanent successor .

REASONING

Extraction is indicated of over -r etained pr imar y teeth that

do not exfoliate when permanent successor s erupt,

especially if the permanent tooth is displaced f r om the ar ch

or oral hygiene is poor in that ar ea. Refer for opinion if

concerned.

FIGURE 19: Over-retained primary teeth. They

need to be extracted if they fail to exfoliate

when permanent sucessors erupt.

FIGURES 20-22: Aesthetic component criteria.



5. Harrison, J.E., Ashby, D. Or thodontic tr eatment for poster ior cr ossbites.

Cochrane Database Syst Rev 2001; (1): CD000979. Review. Pu

bMed PMID:112796991.

6. Schütz-Fransson, U., Bjerklin, K., Lindsten, R. Long-term follow-up of

or thodontically tr eated deep bite patients. Eur J Orthod 2006; 28 (5): 503-

512.

7. Ericson, S., Kurol, J. Ear ly tr eatment of palatally erupting maxillar y canines

by extraction of the pr imar y canines. Eur J Orthod 1988; 10 (4): 283-295.

8. Bjerklin, K., Al-Najjar, M., Kårestedt, H., Andrén, A. Agenesis of

mandibular second pr emolar s with r etained pr imar y molar s: a longitudinal

radiographic study of 99 subjects f r om 12 year s of age to adulthood. Eur J

Orthod 2008; 30 (3): 254-261.

9. Bjerklin, K., Kurol, J., Valentin, J. Ectopic eruption of maxillar y fir st

permanent molar s and association with other tooth and developmental

distur bances. Eur J Orthod 1992; 14 (5): 369-375.

10. Zhang, M., McGrath, C., Hägg, U. Or thodontic tr eatment need and oral

health-r elated quality among childr en. Community Dent Health 2009; 26

(1): 58-61.

11. Orthodontic Review Group. Or thodontic Review Gr oup Repor t 2007,

Page 21: http://www.hse.ie/eng/Publications/ser vices/Childr en/

Or thodontic_Review_Gr oup_Repor t.html

Dr Ciara Scott is a Specialist in Orthodontics at the Regional Orthdontic Unit,St Columcilles Hospital, Dublin, and private practice in Greystones, Co. Wicklow.

Dr Sheila Hagan is a Specialist Registrar in Orthodontics at the Regional

Orthodontic Unit, St James’s Hospital, Dublin, and the Dublin Dental Hospital.

DIARY OF EVENTS



SEPTEMBER

IDA Golf Society – Captain’s Pr ize

September 5 Car low Golf Club

Council of the Ir ish Dental Association – Meeting

September 12 IDA House

Metr opolitan Br anch – Joint Endodontic Scientific Meeting

September 17 Dublin 4 Hotel

Fur ther details to follow when available

Ir ish Academy of Amer ican Gr aduate Dental Specialists

(IAAGDS) – Annual Scientific Confer enceSeptember 26 Conrad Hotel, Ear lsfor t Terrace, Dublin 2

Time: 9.00am-1.00pm (shor t lectur es). Fr ee to attend for all dentists.

OCTOBER

Public Dental Surgeons Seminar 2009

October 7-9 Whites Hotel, Wexfor d

Metr opolitan Br anch – Scientific Meeting: ‘Cr oss Infection

Contr ol’

October 9 Dublin 4 Hotel


NOVEMBER


November 14 IDA House

Munster Br anch – Annual Scientific Meeting

November 20 Sheraton Hotel, Fota Island, Cor k

Speaker : Dr Jens Andr easen, on ‘Dental traumatology’. All enquir ies to IDA

House, Tel: 01-295 0072

Metr opolitan Br anch – Scientific Meeting – Restor ative Dentistr y

November 26 Dublin 4 Hotel


DECEMBER

IDA Golf Society – Chr istmas Hamper

December 11 The Royal Dublin Golf Club

FEBRUARY 2010


Februar y 6 IDA House

APRIL 2010


Apr il 17 IDA House

MAY 2010

IDA Annual Confer ence: ‘Pear ls of Wisdom’

Ma y 12-15 Radisson Hotel, Galwa y

Documents

PericoronitisAugSept09_2