The evaluation of direct composite restorations for the worn mandibular anterior dentition – clinical performance and patient satisfaction

The evaluation of direct composite restorations for the worn

mandibular anterior dentition – clinical performance and

patient satisfaction

N. J. POYSER*,†, ‡, P . F. A. BRIGGS*,†, H. S. CHANA*,§, M. G. D. KELLEHER†,

R. W. J. PORTER*,† & M. M. PATEL* *Department of Restorative Dentistry, St George’s Hospital, London,†Department of Restorative Dentistry, King’s College London Dental Institute at Guy’s, King’s College and St Thomas’ Hospitals, London,‡Department of Hospital Dentistry, Mayday University Hospital, London and §Department of Restorative Dentistry, Kingston Hospital, Surrey,

London

SUMMARY This prospective split-mouth clinical trial

evaluated the performance and patient satisfaction

of 168 Herculite XRV direct composite restorations

bonded to the worn anterior dentition of 18 patients

with localized anterior tooth surface loss. One hun-

dred and six of these restorations were placed on the

mandibular anterior teeth. The restorations in-

creased the anterior occlusal vertical dimension

between 0Æ5 and 5 mm and the posterior occlusal

contacts were restored after a mean duration of

6Æ2 months (range: 3–13 months) in 14 out of the 15

‘Dahl’ sub-group patients. The restorations were

evaluated after 2Æ5 years of service by five examiners.

Four patients and 23 mandibular restorations were

lost to follow-up. Multiple clinical and restorative

variables were assessed to determine their influence

on restoration performance. Complete failure oc-

curred in 6% of the restorations. Circumferential

preparation and height of the restorative addition

did not influence the performance of the restorations.

A Visual Analogue Scale (VAS) was used to assess the

patient’s opinion regarding sensitivity, aesthetics,

longevity and function of the worn mandibular

anterior teeth. A statistically significant difference

(95% CI) was found between the pre-operative and 1-

month review VAS responses for aesthetics and

longevity and this was maintained at the 2Æ5-year

review. Direct composite restorations placed at an

increased occlusal vertical dimension are a simple

and time-efficient method of managing the worn

mandibular anterior dentition. Patient’s acceptance

and adaptation to the technique is good and the

results are accompanied with a high level of patient

satisfaction that is maintained for the medium-term.

KEYWORDS: composite resins, vertical dimension,

tooth attrition, tooth erosion, patient satisfaction,

prospective studies, adult

Accepted for publication 31 August 2006

Introduction

Tooth surface loss (TSL) can be caused by attrition,

erosion, abrasion and abfraction (1). The frequent

clinical finding is that they are often acting in combi-

nation (2). The management of the worn mandibular

anterior dentition is a restorative challenge. The prob-

lems frequently encountered are the lack of interoc-

clusal space owing to dento-alveolar compensation (3),

and problems related to the diminutive nature of these

teeth. Adopting a conventional prosthodontic approach

(i.e. conventional crowns) to manage the worn man-

dibular anterior dentition is not without complication.

Optimal preparation design will significantly weaken

the residual tooth tissue and often compromise the

integrity of the pulp. Frequently insufficient and inap-

propriate reduction is performed and the resulting

restoration may compromise periodontal health or

aesthetic outcome. In such situations, the placement

of direct composite restorations at an increased occlusal

ª 2007 Blackwell Publishing Ltd doi: 10.1111/j.1365-2842.2006.01702.x

Journal of Oral Rehabilitation 2007 34; 361–376

vertical dimension and utilizing the ‘Dahl Concept’ (4)

by relative axial tooth movement might be beneficial.

The reader is invited to refer to a paper recently

published by the authors that provides a summary of the

‘Dahl Concept’ and discusses these issues further (5).

Direct composite is increasingly being used for the

restoration of worn teeth as the material is inexpensive,

easy to use and repair, and can provide an acceptable

aesthetic result. Importantly, it can be placed with

minimal tooth preparation. Although the evidence for

its use as a medium-term restorative material is increas-

ing (6, 7), there has been limited research regarding the

technique specifically for the worn mandibular anterior

dentition. Evidence relating to the patient satisfaction of

this restorative technique is also limited.

This clinical study was prospectively designed and

executed to evaluate the following:

1 The re-establishment of posterior occlusal contacts

following the placement of anterior fixed composite

‘Dahl’ appliances at an increased occlusal vertical

dimension.

2 The internalization of the restorations. (When the

patient accepts the restoration as being part of them)

3 The time taken to place the restorations.

4 The medium-term performance of the restorations

placed for the worn mandibular anterior teeth.

5 To ascertain whether tooth preparation improved the

performance of the restorations.

6 To identify factors associated with restoration failure.

7 To determine patients’ thoughts about the treatment

and whether positive benefits are maintained over a

period of time.

Method

Pre-operative

Sample. Ethical approval for the study was obtained

from the St George’s Hospital ethical standards com-

mittee. The patients were recruited from the new

patient restorative consultation clinics at St George’s

Hospital. All of the patients had been referred by their

general dental practitioner for the management of TSL.

The inclusion criteria for acceptance into the study are

shown in Table 1. Patients were invited to join the

study and all were provided with verbal and written

information (5).

The proposed treatment and implications were dis-

cussed with the patient prior to gaining informed

consent and commencing treatment. An aspect of the

study was to investigate whether tooth preparation

influenced the survival of the restorations. The patients

were randomly allocated into two groups (by the toss of

a coin) and this determined which side of the dental

arch was to receive tooth preparation prior to the

placement of the restorations.

VAS questionnaire. All patients were assessed and

treated by one clinician with predefined procedures

and criteria. At the initial visit, prior to recording

baseline records or commencing treatment, patients

were asked to complete a ‘before treatment question-

naire’. The questionnaire asked the patients to mark

their response to four questions on a 100-mm

horizontal VAS, marked ‘Not at all ’ at left end and

‘A lot ’ at the right end. It was stated that the

questions were specifically in relation to their worn

lower anterior teeth. The questions were concerned

with sensitivity, aesthetics, longevity and function of

these worn lower teeth. The patients were asked four

questions:

1 How badly do hot or cold drinks, cold air or sweet

foods affect your lower teeth?

2 How concerned are you about the look of your lower

teeth?

3 How concerned are you about the life span of your

lower teeth?

4 How much do your lower teeth reduce your ability to

chew foods?

The response on each VAS was measured to the

nearest millimetre.

Pre-operative records. A thorough history and clinical

examination was undertaken and baseline records were

recorded on a ‘Clinical Assessment Sheet’. Every effort

was made to determine the aetiology of the TSL and to

assess whether parafunctional habits were involved.

Patients were offered appropriate preventative advice

Table 1. Inclusion criteria

Tooth surface loss primarily affecting the mandibular anterior

teeth

At least four teeth affected and require treatment

Teeth to have no existing restorations

Significant tooth wear with dentine involvement

and a reduction in clinical height

Stable periodontal status

N . J . P O Y S E R et al.362

ª 2007 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 34; 361–376

prior to commencing any restorative treatment.

Pre-operative radiographs were taken to assess the

periapical status. The clinical features recorded during

the baseline record taking are shown in Table 2. The

incisal relationship and aetiology of the TSL was

independently evaluated by the authors using infor-

mation from the patients’ history, clinical examination,

digitized colour slides and pre-operative study models.

A consensus was made for those cases where there was

disagreement.

Clinical procedure

Clinical set-up. Great effort was made to control the

variables encountered during the clinical procedure.

1 All of the teeth requiring restorations were restored

with Herculite XRV composite and Optibond dentine

bonding agent*.

2 All of the mandibular teeth were restored at the same

visit. If the opposing dentition required restoration,

then this was provided at a subsequent appointment,

usually 4 weeks later.

3 All the patients were treated in the same clinical

setting with the same conventional light-curing unit†.

4 Clinical assistance was provided by the same experi-

enced dental nurse who was familiar with the compos-

ite build-up technique.

5 A dental shade‡ was taken prior to commencing the

clinical procedures.

6 Alginate impressions were taken for study casts and

all impressions were poured immediately by the same

qualified dental technician.

7 Pre-operative clinical photographs (1:1 magnified)

were taken using a Yashica Dental Eye III camera§ and

Kodachrome 64 colour slide film¶

Tooth preparation. The teeth on the side of the arch

chosen for preparation were prepared to a chamfer

margin to the criteria shown in Fig. 1 with a rounded-

ended tapered diamond bur (Bur No. 723Æ10C¶) in a

water-cooled air-turbine. All margins were kept in

enamel wherever possible. The aim was to improve the

resistance form of the restoration and to increase the

area of enamel available for bonding. No tooth prepar-

ation of the contra-lateral teeth was undertaken. An

alginate impression and clinical photographs (1:1 mag-

nification) were taken of the preparations.

Clinical procedure. A stopwatch was started to record the

time required for the remainder of the procedure. The

teeth were isolated with rubber dam and then cleaned

with a slurry of pumice and water. Clear cellulose strips

were used to separate interproximal contact points if

required. The enamel was etched for 30 s with 37%

phosphoric acid gel, washed for 30 s, and then dried

with a light stream of air from the 3-in-1 to avoid

desiccation of the dentine. Enamel and dentine bonding

was carried out according to the manufacturer’s instruc-

tions. The teeth were individually built-up with a bulk of

composite material. The aim was to restore the natural

height and aesthetic form. The composite was cured for

Table 2. Clinical features recorded at baseline

Incisal relationship

Occlusal vertical dimension

Periodontal parameters (pocket probing depth, bleeding on

probing, mobility and labial gingival recession)

Sensibility (ethyl chloride and electric pulp tester)

Degree of wear (Smith and Knight Tooth Wear Index) (8)

Height of the teeth

Shape of the incisal edge

Nature of the opposing dentition

1·0 mm

0·5 mm

Fig. 1. Preparation design for the circumferential enamel

chamfer.

*Kerr UK Ltd, Peterborough, UK†UnoDent Curing Light, UnoDent Ltd, Witham, UK‡Vitapan Classic, VITA Zahnfabrik, H Rauter GmbH, Bad Sackingen,

Germany

§Kyocera Corporation, Denville, NJ, USA¶Eastman Kodak Company, Rochester, NY, USA

D I R E C T C O M P O S I T E F O R T H E M A N D I B U L A R A N T E R I O R D E N T I T I O N 363


40 s labially and a further 40 s lingually. Additional

increments were applied, if necessary. Gross adjustment

of the morphology of the composite was performed with

a tapered diamond bur in a water-cooled air-turbine

prior to commencing the build-up of the adjacent tooth.

Once all of the teeth were restored, the rubber dam was

then removed. The incisal aspects of the restored teeth

were adjusted to provide stable and even contacts with

as many opposing teeth as possible. Protrusive and

lateral excursive contacts were assessed with articula-

ting paper and adjusted to provide as smooth and even

anterior guidance as possible. Judicious adjustment was

carried out so that the appearance of the restorations

was not compromised. Canine guidance was established

in lateral excursion, if possible. The restorations were

finished with composite finishing burs, Sof-Lex discs

and interproximal polishing strips**. The stopwatch was

stopped and the time taken was recorded.

Immediate post-operative records. Post-operative clinical

observations were recorded of the occlusal contacts in

the new intercuspal jaw relationship, occlusal contacts

in excursions and the height of the restored teeth.

A post-operative measurement of the occlusal vertical

dimension was taken (if maxillary restorations were to

be provided, this measurement was recorded after these

were placed at a subsequent appointment). An alginate

impression, wax interocclusal registration and clinical

photographs (1:1 magnification) were taken of the

restorations.

Once again patients were warned about the increased

occlusal vertical dimension and advised what to expect.

They were instructed on appropriate methods of

homecare for their restored dentition.

Post-operative review – initial reviews until occlusal re-

establishment (N.P. only)

Post-operative follow-up was at 1, 3 and 6 months

following the placement of the mandibular restorations,

and then 3 monthly if the occlusion was yet to re-estab-

lish occlusal contacts. The patients were then reviewed

at 6 monthly intervals. At the initial 1-month review

appointment, patients were asked to complete an ‘after

treatment questionnaire’. The questionnaire was iden-

tical to the ‘before treatment questionnaire’ and the

patients were asked to focus on their lower anterior teeth

now that they had been restored. The patients did not

have access to their ‘before treatment questionnaire’.

At the review visits, the patients were questioned

regarding pulpal, periodontal and musculoskeletal

symptoms. They were asked when they considered

the restorations were part of them, a concept referred to

as internalization. The restored teeth were then

assessed with regard to their periodontal status, vitality

and restoration status. The re-establishment of posterior

occlusal contacts was assessed with Shimstock metal

foil††. Alginate impressions, a wax interocclusal regis-

tration and clinical photographs (1:1 magnified) were

taken.

Post-operative review – 2Æ5-year review (N.P., P.B., H.C.,

M.K., R.P., M.P.)

A multi-examiner assessment of the patients was

carried out at 2Æ5 years. All of the initial 18 patients

were invited by post to attend the review day. Non-

responders were contacted by telephone on two occa-

sions. Patients were given an appointment time as

convenient as possible for them but on a first-come-first

serve basis. The patients were not seen for review in the

same order in which they had been treated. Clinical

assessment of all the respondents was carried out on a

single day by five examiners.

Prior to clinical review. Patients were asked to complete a

questionnaire and VAS questionnaire immediately

prior to the clinical assessment. The VAS questionnaire

was the same as what had been used at the 1-month

re-assessment.

Assessment by N.P. The patients were questioned

regarding pulpal, periodontal and musculoskeletal

symptoms. The restored mandibular anterior teeth

were assessed with regard to their periodontal status

(pocket probing depth, bleeding on probing, mobility,

tenderness to percussion and labial gingival recession).

Sensibility testing was performed with an electric pulp

tester‡‡ and a cotton pellet cooled with Ethyl Chlor-

ide§§. The height of the teeth, the pattern of wear and

the nature of the opposing dentition were recorded.

**3M ESPE Dental Products, St Paul, MN, USA

††Hanel-GHM-Dental GMBH, Nurtingen, Germany‡‡Kerr Vitality Scanner; Kerr UK Ltd, Peterborough, UK§§Roche Consumer Healthcare, Welwyn Garden City, Hertfordshire,

UK



Alginate impressions were taken for study casts.

Clinical photographs (1:1 magnified) were taken using

a Yashica Dental Eye III camera§ and Kodachrome 64

colour slide film¶.

Assessment by, P.B., H.C., M.K., R.P., M.P. The restorations

were assessed according to a predetermined assessment

protocol that is shown in Table 3. The team had devised

and tested the protocol at an examiner-training day

4 weeks prior to the review day.

During the assessment, each patient remained in the

same dental chair and each examiner independently

assessed the patient in turn. Visual assessment was

performed on dry teeth using the dental light and

without auxiliary magnification. The teeth were dried

using a stream of air from the 3-in-1. Tactile assessment

was carried out under the same conditions and with a

WHO periodontal probe. In addition to the evaluation

of the composite restorations, some of the examiners

had other aspects of evaluation to complete. Occlusal

assessment was carried out with shimstock occlusal foil

[Shimstock metal foil†† by one examiner (H.C.) and

interocclusal wax registration* of the position of maxi-

mum intercuspation by one examiner (P.B.)]. One

examiner (M.K.) took parallel technique periapical

radiographs of the mandibular anterior teeth. The

radiographs were examined using a light-box and

magnification. The examiners had access to the imme-

diate post-operative study models to help determine the

loss of restorative material.

The data were entered into a MICROSOFT EXCEL database

for statistical analysis.

Results

Initial group – 18 patients

Eighteen patients (14 males and four females) between

31 and 75 years of age (mean 52 years) participated in

this clinical study. The tooth wear was thought to be of

combined aetiology in eight patients, predominantly

erosive in eight patients and predominantly attritional

in two patients. One hundred and sixty-nine direct

composite restorations were placed on the worn anter-

ior teeth of these 18 patients. One hundred and six of

these restorations were placed on the mandibular

anterior teeth.

Fifteen of the patients had the restorations placed as

fixed ‘Dahl’ appliances. The other three patients had the

restorations placed as part of a planned treatment to

reorganize the occlusal scheme at an increased vertical

dimension. The restorations created an immediate post-

operative increase in the occlusal vertical dimension

between 0Æ5 and 5 mm anteriorly. The demographics

and clinical findings of the 18 patients that participated in

the study are shown in Table 4. No preparation was

Table 3. Clinical assessment criteria used to evaluate the restorations

Visual assessments – dry teeth, dental light, visual inspection without magnification

Anatomical form (% of tooth volume lost) I <10% loss

II 50–90% still remaining

III <50% still remaining

Restoration staining (labial/incisal surfaces only) I None – no staining on the surface of the restoration is visible

II Mild – <25% of the surface of the restoration is stained

III Moderate – <50% of the surface of the restoration is stained

IV Severe – >50% of the surface of the restoration is stained

Marginal discolouration (whole labial margin only) I No staining – no staining of the margin is visible

II Staining – staining of the margin is visible

Colour match (labial/incisal surfaces only) I Acceptable – the restorative material matches the adjacent tooth structure

II Unacceptable – the match between the restorative material and

adjacent tooth structure is beyond an acceptable range

Tactile assessments – dry teeth, dental light, WHO probe

Surface roughness (labial/incisal surfaces only) I Smooth – the surface of the restoration feels smooth to the probe

II Rough – the surface of the restoration feels rough, pitted or grooved

Marginal adaptation (whole labial margin only) I No catch – the probe does not catch when drawn over the

margin of the restoration

II Catch – the probe does catch when when drawn over the margin of

the restoration

¶¶Dental Wax, Moyco Union Broach, York, PA, USA



carried out for patients 8 and 10. Patient 8 had TSL

predominantly affecting the labial and interproximal

aspects of his teeth and there was minimal loss of clinical

height. Tooth preparation would have led to the loss of

the little enamel that was remaining. Patient 10 had TSL

that was predominantly erosive in nature and affecting

the incisal edges. It was felt that there was no need to

prepare the ‘cupped-out’ erosive facets.

The majority of the patients’ mandibular anterior teeth

had Tooth Wear Index (TWI) (8) scores of 3 and 4 on the

incisal aspect of the teeth (Loss of enamel and substantial

loss of dentine with exposure of secondary dentine in

many cases) (Table 4). The majority of the buccal aspects

had TWI scores of 1 and 2 (Loss of enamel characteristics

and loss of enamel just exposing dentine). The mean

height and range of heights of the anterior mandibu-

lar dentition pre-operative and post-operatively is

presented for each patient in Table 5. The composite

restorations restored approximately 28% (range: 8–

48%) of the final post-operative tooth volume.

Re-establishment of occlusal contacts. In the ‘Dahl’ sub-

group of patients, the posterior occlusion was restored

after a mean duration of 6Æ2 months (range:

3–13 months) in 14 out of the 15 cases. One of the

cases (patient 3) had failed to re-establish posterior

occlusal contacts.

Internalization. Seventeen patients fully accepted the

restorations as being part of themselves and therefore

had achieved internalization. The patient who failed to

achieve internalization reported actively avoiding the

restorations whilst eating in an attempt not to fracture

them. The majority of patients reported that internal-

ization occurred after approximately 1 week (range:

0Æ5–12 weeks).

Procedure time. The mean time taken to place the

restorations on the mandibular anterior teeth for each

patient was 64 min (range: 48–80 min). The mean time

per tooth was calculated to be approximately 11 min.

Review group – 14 patients

Patient demographics and clinical status. Fourteen patients

of the initial 18 study patients participated in the

clinical review day (a review rate of 78%). Four

patients were lost to follow-up; one patient had died,

Table 4. Patient demographics, clinical features, Tooth Wear Index (8) (incisal and buccal) of the mandibular anterior teeth to be restored

(previously restored teeth were not included) and restoration status

Pt.

No. Age Sex Aet.*

Incisal

rel.

TWI incisal

mean (range)

TWI buccal

mean (range)

Total no. of

restns placed

No. of restns

placed LLS

Previously

estored LLS †teeth

Prep.

side

Incr.

OVD‡ (mm)

Dahl

case

1 48 M E II div. 1 3Æ60 (3–4) 1Æ60 (1–3) 10 6 1 L 2 d

2 53 M E I 4Æ00 1Æ00 12 6 0 R 2Æ5 d

3 54 M E III 4Æ00 1Æ00 12 6 0 L 1Æ5 d

4 75 F C I 4Æ00 3Æ80 (3–4) 6 6 1 R 2 d

5 65 M E I 4Æ00 2Æ40 (1–3) 10 5 0 L 5

6 59 M C II div. 1 4Æ00 1Æ00 6 6 0 L 2 d

7 38 F A II div. 1 4Æ00 0Æ00 8 6 0 R 2 d

8 58 M E III 3Æ40 (3–4) 3Æ00 11 5 0 None 0Æ5 d

9 42 F C II div. 1 3Æ83 (3–4) 0Æ00 6 6 0 R 2Æ5 d

10 31 M E I 3Æ00 1Æ00 6 6 1 None 1 d

11 34 M A II div. 1 3Æ50 (2–4) 0Æ00 7 6 0 R 2Æ5 d

12 65 M C II div. 2 4Æ00 1Æ00 10 6 1 L 2Æ513 71 M C II div. 1 4Æ00 1Æ25 (1–2) 6 6 2 R 1 d

14 46 M E I 4Æ00 1Æ00 11 6 0 R 1Æ5 d

15 52 M E I 4Æ00 1Æ83 (1–3) 12 6 0 L 4 d

16 34 F C II div. 2 2Æ17 (1–4) 0Æ67 (0–1) 12 6 0 L 2Æ5 d

17 44 M C III 4Æ00 1Æ67 (1–3) 11 6 0 R 4

18 63 M C II div. 1 4Æ00 0Æ00 12 6 0 L 3 d

*Aetiology: A-attrition, E-erosion, C-combination†LLS: Lower labial sextant‡OVD: occlusal vertical dimension



one refused to attend because of work commitments,

and it was not possible to contact two patients. The

absence of these four patients resulted in the loss of 23

mandibular restorations to follow-up. The patients of

the review group were aged between 31 and 75 years of

age (mean age 53 years) when the composite restora-

tions were initially placed. A total of 133 direct

composite restorations were placed on the worn anter-

ior dentition. Of these 83 restorations were placed on

the worn mandibular anterior teeth. Each patient had

all of their six mandibular anterior teeth restored except

patient 8 who had five of his six mandibular anterior

restored, as the other tooth did not require restoration.

Six of the mandibular restorations were excluded from

the study as the teeth had existing restorations present

(patients 1, 4, 10, 12 and 13).

Occlusal contacts. After initial placement, 50 of the 77

restorations (65%) had contact with the opposing

dentition in the new intercuspal position. Fifty-four of

the 77 restorations (70%) were involved in excursive

guidance. The contacts by tooth are shown in Fig. 2.

Nature of the opposing dentition. The nature of the

occlusal surfaces of the teeth of the upper labial sextant

when the composite restorations were placed initially is

presented in Table 6. For the majority of patients, this

remained the same throughout the study. However,

some restorations were changed. Patient 18 had the

UR2 changed from composite to a porcelain fused-to-

metal crown with a palatal surface comprising of metal

and ceramic. Patient 12 had the UR2-UL2 changed from

composite restorations to four units of porcelain fused-

to-metal crown and bridgework with palatal surfaces

comprising of metal and ceramic. The UR3 changed

Table 5. The mean height of the anterior mandibular dentition pre-operatively and post-operative, and the mean height the composite

addition of the teeth (previously restored teeth were not included)

Pt. ID

Pre-operative height (mm)

Buc. rec.*

Post-op height (mm) Height of comp. addition to

incisal aspect of tooth (mm)

Mean (range) Buccal (range) Mean (range) Buccal (range) Mean (range)

1 5Æ2 (2–7) – 1Æ8 7Æ2 (5–9) – 2Æ0 (1–3)

2 5Æ5 (4–8) 5Æ3 (3–8) – 7Æ5 (6–10) – 2Æ0 (1–3)

3 8Æ0 (7–10) 7Æ5 (6–10) 0Æ7 9Æ0 (8–11) – 1Æ04 8Æ0 (7–9) 4Æ0 (2–6) – 8Æ4 (8–9) – 0Æ4 (0–1)

5 8Æ8 (7–11) 6Æ4 (5–10) – 11Æ0 (10–13) – 2Æ2 (2–3)

6 8Æ3 (7–10) 6Æ3 (5–8) – 9Æ7 (8–11) 9Æ0 (8–11) 1Æ33 (1–2)

7 4Æ7 (4–6) – – 7Æ5 (7–9) – 2Æ83 (2–3)

8 10Æ0 (9–13) – – 10Æ0 (9–13) – 0†

9 5Æ3 (4–7) 4 (2–6) 1Æ8 7Æ3 (6–9) 7Æ0 (5–9) 2Æ0 (1–3)

10 7Æ8 (7–8) 7Æ6 (7–8) – 8Æ4 (7–9) – 0Æ6 (0–1)

11 7Æ3 (6–10) 6Æ7 (5–9) – 8Æ5 (7–10) – 1Æ2 (1–2)

12 8Æ0 (7–9) 5Æ6 (5–7) – 9Æ0 (8–10) – 1Æ013 5Æ5 (4–7) 5Æ3 (4–7) – 8Æ5 (8–9) – 3Æ0 (1–5)

14 6 (5–7) 5Æ7 (5–7) – 8Æ3 (7–10) – 2Æ3 (2–3)

15 7 (6–8) 6Æ0 (5–7) – 8Æ2 (7–9) – 1Æ2 (1–2)

16 6Æ2 (5–8) 4Æ3 (2–7) – 7Æ8 (7–9) – 1Æ7 (1–2)

17 3Æ7 (3–5) 2Æ8 (1–5) – 6Æ2 (5–7) – 2Æ5 (2–3)

18 5Æ2 (4–6) 4Æ5 (4–5) – 7Æ5 (7–9) – 2Æ3 (1–3)

*Buccal gingival recession.†Labial composite addition.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

LR3 LR2 LR1 LL1 LL2 LL3

ICP contact Exc. contact

Fig. 2. Percentage of restorations with contacts in the intercuspal

position (ICP) and excursive movements.



from composite to a nickel–chromium metal alloy resin

bonded bridge wing retainer.

Restoration performance

Inter-examiner agreement. The level of agreement be-

tween the examiners for each clinical assessment

variable is shown in Table 7. For example, when

assessing the anatomical form, for 44% of the restora-

tions, all five examiners rated the restorations in the

same category, for 24% of the restorations four out of

the five examiners rated the restorations in the same

category, and for 32% of the restorations three out of

the five examiners rated the restorations in the same

category. Where there was disagreement between

examiners, the rating was never different by more than

one rating increment. The mathematical ‘mode’ of the

examiner results was used to definitively score the

restorations.

Complete failures. Six per cent of the study restorations

failed completely (i.e. total loss of the restoration)

during the study period. These were complete bulk

failure with no remaining composite on the tooth

surfaces. The clinical features of these failure cases are

shown in Table 8.

Because of the small sample size and small number of

failures, statistical evaluation was inappropriate. How-

ever, the majority of the failed restorations were

situated on the right hand side. This might be due to

operator technique and the fact that restorations might

be more difficult to place in this site for a right-handed

operator.

Partial failures Eighty-six per cent of those restorations

that had not completely failed had greater than 90% of

the post-restorative tooth volume. The other 14% had

between 50% and 90% still remaining. The loss of

material was due to wear rather than fractures and

chipping reported by other authors (6, 7). A frequent

observation was that the majority of composite resto-

rations had evidence of incisal wear at the early

reviews. The restorations were frequently constructed

with a flat incisal edge; however, at the initial reviews

(1 or 3 months) faceting of <10% was noted, which

provided an inclined contact area of a greater surface

area with the opposing dentition. Following this ‘self-

adjustment’, the progression of restoration wear was

minimal.

Restoration staining. Eight-one per cent of the remaining

restorations had no staining on the labial and/or incisal

surfaces. The other restorations (19%) exhibited mild

staining, but none of the patients were concerned about

this. In the authors’ experience, the degree of compos-

ite surface staining is greater in patients that smoke

tobacco products compared with non-smokers. Unfor-

tunately, it was not possible to investigate this further

as none of the patients in the study smoked. Composite

staining, especially in smokers, might be one of the

main disadvantages of this technique. Smokers should

be informed of the likelihood of composite staining pre-

operatively and the potential need for frequent main-

tenance and/or restoration replacement. If restoration

staining is likely to be a significant cosmetic issue, then

a move towards alternative restorations, such as the use

of ceramics, may be required.

Marginal discolouration. Seventy-four per cent of the

remaining restorations had no evidence of marginal

discolouration on the labial aspect. The remainder

(26%) had evidence of staining, which was of no

concern to the patient and required monitor and

review. None of the restorations required refinishing,

repair or replacement.

Colour match. Of the remaining restorations, all were

deemed to have an acceptable colour match. The colour

Table 6. Nature of the opposing static and dynamic occlusal

contacts

Nature of opposing occluding surface No. of teeth % of teeth

Direct composite resin 38 49

Natural tooth/composite 14 18

Natural tooth only 10 13

PFM* – metal and ceramic 12 15

PFM – ceramic only 3 4

RBB† – metal wing 1 1

*PFM: porcelain fused-to-metal restoration.†RBB: resin bonded bridge.

Table 7. Level of agreement between examiners for each clinical

assessment variable

Level of agreement 5 examiners 4 examiners 3 examiners

Anatomical form 44% 24% 32%

Restoration staining 33% 28% 39%

Marginal discolouration 49% 33% 18%



stability of the composite resin appeared to be good and

a change in the intrinsic colour of the teeth was not

apparent during the study period.

Surface roughness. Of the remaining restorations, all

were deemed to have a smooth surface on the labial

and incisal surfaces.

Marginal adaptation. Forty-six per cent of the restora-

tions had no catch on the labial aspect. The remainder

(54%) had evidence of a catch requiring monitoring.

No restoration required refinishing, repair or replace-

ment.

Wear of the opposing dentition. There was no evidence of

wear of the natural tooth substance by the composite

restorations.

Periodontal health. The presence of the restorations did

not have a detrimental effect on periodontal parame-

ters. The pre-operatively and the 2Æ5-year review

findings are shown in Table 9. The periodontal pocket

depths and bleeding on probing was not assessed for

one patient (patient 14) as they required antibiotic

prophylaxis for periodontal probing.

Pre-operatively 7 out of 13 patients (54%) and 16 out

of 71 sites (23%) exhibited bleeding on probing. At the

2.5-year review, 5 out of 13 patients (38%) and 10 out

of 71 sites (14%) had evidence of bleeding on probing.

This observation supports the findings of other studies

regarding this technique (7). The improvement in

bleeding on probing might be due to the fact that

many patients report difficulty and soreness whilst

brushing their teeth when they are short and worn.

Also patients might prefer the appearance of their teeth

post-operatively and wish to make more of an effort to

look after their teeth now that they have been restored.

Increased tooth mobility was seen in one patient

(patient 16) as two teeth exhibited grade 1 mobility

(LL2 and LL3) at review. These teeth were periodon-

tally intact. This patient had combination TSL. The two

restored teeth had no features that were significantly

different from the other restored teeth.

Occlusal re-establishment. All of the ‘Dahl’ subgroup of

review patients had experienced re-establishment of

the posterior occlusal contacts by 13 months. Closer

examination of the posterior occlusal contacts was

performed at the 2Æ5-year review with the use of

Shimstock metal foil. This revealed that one-third of

the ‘Dahl’ subgroup of patients had only achieved

Table 8. Details of completely failed restorations – (a) patient and

tooth demographics and (b) restorations details

(a)

Pt.

ID Age Sex Aet. Incisal rel. Tooth

Surface

shape*

TWI

I

TWI

B

1 48 M E II div. 1 LL3 Cup 4 1

4 75 F C I LR3 Incline 4 3

4 75 F C I LR2 Incline 4 4

13 71 M C II div. 1 LR2 Flat 4 1

15 52 M E I LR2 Cup 4 1

(b)

Pt.

ID

Pre-

operative

height

(mm)

Prep.

Post-

operative

height

(mm) Comp

add.

(mm)

Immediate

Post-

operative

tooth

contactsOpposing

surfaceMax Buc Max Buc ICP† Excur.

1 7 7 Y 9 – 2 Y Y Dir. Comp.

4 9 6 Y 9 – 0 Y Y Enamel

4 9 5 Y 9 – 0 Y Y PFM-M/C

13 4 4 Y 9 – 5 N Y Enamel

15 7 7 N 8 – 1 N N Dir. Comp.

*Shape of worn tooth surface: cup-cupped facet, inclined-inclined

surface, flat-horizontal surface.†ICP: intercuspal position.‡Aetiology: A-attrition, E-erosion, C-combination.

Table 9. The periodontal status of the restored mandibular

anterior teeth pre-operatively and at 2Æ5-year review [(a) tooth

basis and (b) patient basis]

Pre-operative Review

(a)

Number of restored teeth

Bleeding on probing

(one or more sites per tooth) (n ¼ 71)

16 10

Pocket depth (4 mm or greater) (n ¼ 71) 1 0

Mobility (n ¼ 77) 0 2

Tenderness to percussion (n ¼ 77) 2 1

(b)

Number of patients

Bleeding on probing

(one or more sites per tooth) (n ¼ 13)

7 5

Pocket depth (4 mm or greater) (n ¼ 13) 1 0

Mobility (n ¼ 14) 0 1

Tenderness to percussion (n ¼ 14) 2 1



partial re-establishment as incomplete occlusal contact

was observed in the premolar regions. These findings

are similar to those found by Redman et al. (7).

However, none of the patients were aware of this or

expressed a desire to have more biting contacts.

Statistical analysis

Preparation versus no preparation. The influence of pre-

paration on the performance of the composite restora-

tions was assessed statistically using Fisher’s exact test.

Preparation was shown not to statistically influence

restoration survival, marginal adaptation, or marginal

discolouration. The contingency tables and P-values are

shown in Table 10.

Effect of restoration height on performance. The height of

restorative material added to the teeth was statistically

shown not to influence the performance of the resto-

rations with regard to restoration survival, marginal

adaptation and marginal discolouration. The height at a

cut-off point of 1-, 2- and 3-mm additions was statis-

tically assessed. The contingency tables and P-values for

a 1-mm cut-off height are shown in Table 11.

Patient satisfaction

VAS scores. The mean and standard deviation for the

VAS scores of the 14 review patients recorded pre-

operatively, at the 1-month review and at the 2Æ5-year

review for sensitivity, aesthetics and longevity are

presented in Fig. 3.

Following the placement of direct composite restora-

tions on the worn mandibular anterior teeth, a

statistically significant difference (95% CI) was found

between the pre-operative and 1-month review VAS

responses for aesthetics (t ¼ 6Æ41; d.f. 13;

P ¼ 0Æ000023) and longevity (t ¼ 5Æ93; d.f. 17;

P ¼ 0Æ00005). No statistically significant difference

was seen for sensitivity.

This difference was maintained during the review

period as a statistically significant difference was found

between the pre-operative and 2Æ5-year review VAS

responses for aesthetics (t ¼ 5Æ15; d.f. 13; P ¼ 0Æ0002)

and longevity (t ¼ 3Æ46; d.f. 17; P ¼ 0Æ004). Again no

statistically significant difference was seen for sensitivity.

Subjective assessment. All of the patients felt that the

treatment was in line with what they were expecting, all

felt that they were provided with sufficient information

prior to the procedure, and all would recommend the

procedure to a friend. These positive responses might be

related to the time and information, both verbal and

written, provided at the initial consultation.

Pulpal Vitality. Using a combination of clinical signs and

symptoms, sensibility testing and radiographic assess-

ment, it was determined that none of restored teeth lost

vitality following the placement of the composite

restorations.

Periapical resorption. None of the radiographs showed

evidence of periapical resorption.

Case example

An example of a typical case is shown in Fig. 4.

Table 10. Statistical evaluation of whether tooth preparation

influences restoration survival, marginal adaptation or marginal

discolouration

Restoration

survival

Marginal

adaptation

Marginal

discolouration

Present Lost Catch

No

catch Staining

No

staining

Preparation 30 4 21 10 10 20

No preparation 42 1 19 23 9 33

P-value

(two-tailed)

0Æ1637 0Æ0947 0Æ2886

Stat sign* No No No

*Statistical significance.

Table 11. Statically evaluation of whether the height of the

composite addition (£1 mm vs. ‡2 mm) influences restoration

survival, marginal adaptation or marginal discolouration

Restoration

survival

Marginal

adaptation

Marginal

discolouration

Present Lost Catch

No

catch Staining

No

staining

‡ 2 mm 39 2 21 18 12 27

£ 1 mm 28 3 15 13 7 21

P-value

(two-tailed)

0Æ6457 1Æ000 0Æ7843

Stat sign* No No No

*Statistical significance.



Discussion

Occlusal re-establishment

The posterior occlusion failed to re-establish occlusal

contacts in one of the 15 patients (6%) in which the

composite restorations had been placed as a ‘fixed Dahl

appliance’. This patient was a 54-year-old partially

dentate male, with a Class III incisal relationship, who

exhibited erosive TSL predominantly affecting his

anterior maxillary and anterior mandibular teeth. The

only pre-operative posterior occlusal contact was

0

10

20

30

40

50

60

70

80

90

100

Sensitivity Aesthetics Longevity

Rat

ing

on a

100

mm

VA

S

Pre-operative1-month review2.5-year review

Fig. 3. The pre-operative, 1-month

review and 2.5-year mean Visual

Analogue Scale scores for sensitivity,

aesthetics and longevity (standard

deviation is shown as a vertical line).

Pre-operative anterior view –Intercuspal position

Pre-operative anterior view –Lower labial sextant

Pre-operative occlusal view –Lower labial sextant

Circumferential PreparationLR3 LR2 LR1

Direct Composite RestorationsLR3 to LL3 – Immediate Post-op

One-month review

Six-month review Eleven-month review Thirty-three month review

Fig. 4. Pre-operative and review images illustrating the performance of direct composite restorations over a period of 33 months. The

restorations were placed to restore the worn LR3 to LL3 (LR3 LR2 LR1 were the prepared teeth).



between the upper left 7 and lower left 7 due to a lack of

posterior opposing units. The 12 anterior teeth were

restored as a sextant at a time with a 1-month interval

between appointments. A post-operative increase in the

occlusal vertical dimension of 1Æ5 mm was recorded

anteriorly. There is no obvious explanation for the

failure of the re-establishment of posterior occlusal

contacts. The patient was not concerned and no further

intervention was required. Many authors have attrib-

uted this failure of occlusal movement to a lack of or less

effective eruptive potential (7, 9). The lack of occlusal

movement in this study is in agreement with other

authors. Gough and Setchell (10) reported a failure of

occlusal re-establishment in 4% of cases and Hemmings

et al. (6) reported the same finding in 6% of cases.

The mean time taken for the occlusion to re-establish

was 6Æ2 months. This is in agreement with the time

reported by Hemmings et al. (6) (4Æ6 months), Gough

and Setchell (10) (5Æ9 months), and Redman et al. (7)

(7 months).

Procedural time

It has been suggested that up to 30 minutes per tooth

(6) is required for the restoration of worn anterior teeth

with direct composite resin. This prolonged clinical time

might be a significant reason why alternative indirect

approaches have been suggested. The use of indirect

techniques such as laboratory fabricated composite

polyglass restorations (9) has been suggested to simplify

the clinical method and save chair-side time. However,

the optimal bonding and finishing of indirect adhesive

restorations is technically demanding and can be as

time-consuming as the placement of direct composite

restorations. The use of an indirect technique might

require a greater number of visits and the restorations

are likely to incur a laboratory cost. It is not possible to

make a direct comparison from the literature, as there is

no evidence relating to the time taken to place either

type of restorations.

The reason for adopting one technique over the other

should be related to how well the material performs

clinically and how amenable it is to maintenance. It is

the authors’ opinion that the direct freehand build-up

of teeth with composite resin is the most adaptable and

maintainable. Alternative direct techniques with the

use of a vacuum-formed matrix of a diagnostic wax-up

have been suggested to facilitate the placement of

multiple direct composite build-ups (11, 12). In this

clinical study, the mean time taken to place and finish

six direct composite restorations on the worn mandib-

ular anterior teeth was found to be 64 minutes. The

mean time per tooth to place the 106 direct composite

restorations on the worn mandibular anterior teeth of

all 18 patients was calculated to be approximately

11 minutes. This time is substantially less than the

suggested figure of 30 minutes per tooth (6). The

reasons for the efficient use of time during this study

are thought to be due to having a dedicated surgery

session where all of the equipment and materials are

laid out pre-operatively, working with an experienced

dental nurse, and the type of build-up technique.

Bulk build-up technique

The authors feel that the main reason for the compar-

atively short placement time is because the restorations

were constructed by using a bulk build-up technique. It

is the authors’ opinion that composite resin appears to

survive better if it is placed in thick sections. It is

possible to achieve this thickness if the teeth are built

up to their original morphology and thus increase the

occlusal vertical dimension significantly. In cases with

minimal TSL, it may be better to monitor the situation

rather than to place composite in thin sections that are

more vulnerable to fracture. This is especially true for

mandibular anterior teeth because of the shear and

tensile forces that these teeth are subjected to.

An incremental build-up technique (13) is considered

to be the optimal technique for the placement of

composite resins. The reasons for this are to ensure

complete penetration of the curing light through the

composite and to minimize contraction stresses during

polymerization. The manufacturer recommends that

Herculite XRV composite is not placed in increments

>2 mm. They also suggest that each surface of the

increment is cured for a minimum of 40 s. The

mandibular anterior teeth have a relatively narrow

bucco-lingual dimension, especially at the incisal edge.

Considering these dimensions, there is little concern

about inadequate penetration of the curing light leaving

uncured composite, especially if the restoration is cured

both buccally and lingually for the recommended times.

Filled resin-based materials contract by approxi-

mately 2–3% by volume on polymerization. Polymer-

ization contraction can lead to the formation of stresses

within the cured material or at the bonding surfaces.

These stresses can lead to the deterioration of the



material or debonding at the margins. The potential for

this phenomenon is greatest in cavities with a high ratio

of bonded surfaces to free surfaces, for example a Class I

restoration. In a Class I restoration, there are four

bonded walls and one bonded floor and only one free

unbonded occlusal surface at which contraction may

take place. The ratio of bonded to unbonded surfaces is

known as the Configuration Factor (14). Ideally, this

should be equal to, or less than one, if stresses are to be

avoided. Teeth that have been subjected to TSL tend to

exhibit a relatively flat incisal/occlusal surface for

which to bond to. A composite restoration placed on

such as surface has a favourable configuration factor as

there is one bonded surface and five free unbonded

surfaces at which contraction may take place. For this

reason, a bulk build-up technique for worn teeth with a

relatively flat bonding surface can be confidently

utilized. A bulk build-up technique significantly redu-

ces the time taken to place these restorations as it avoids

the multiple stages involved with the addition and

curing of the increments of composite. It might also

improve the surface integrity as it avoids the potential

of trapping air between increments or insufficient

material adaptation to the previous increment. With a

bulk build-up technique, the restorations can be over-

built and rapidly trimmed to the correct gross mor-

phology with a diamond bur in a high-speed turbine.

Final finishing can be completed in the usual way with

polishing discs, interproximal abrasive strips and pol-

ishing pastes.

Assessment criteria

Modifications of the USPHS assessment have been used

to assess restorations previously. The criteria used in

this study were based on the USPHS criteria, but the

authors felt that modification was necessary in order to

reflect the type of restorative material used, the

conservative management philosophy, patient involve-

ment in the decision-making process, and to provide a

more ‘clinical practice’-based assessment rather than

‘research’-based. The criteria were developed through

group discussion and successfully piloted during the

examiner-training day.

When assessing the performance of different types of

restorations, there is a pressure within the profession to

compare newer alterative restorations to the perceived

‘gold standard’ of a full coverage crown. However,

restorative materials, bonding systems and treatment

philosophies have evolved, so direct comparison is

inappropriate. Large composite restorations placed in

clinical situations where historically a crown would

have been indicated are likely to experience a greater

deterioration of some performance parameters if com-

pared with a crown. The survival of direct composite

restorations is likely to be reduced, but maintenance is

likely to be more favourable. The biological cost of

minimal preparation is preferable.

The USPHS criteria grade restorations according to the

categories Alpha (A), Beta (B) and Charlie (C). A

indicates everything is perfect and intact. B indicates

that inadequacies are evident but clinically acceptable,

and the restorations can be monitored, refinished or

repaired. C indicates that inadequacies are evident and

clinically unacceptable, and replacement of the restor-

ation is required. Unfortunately the USPHS criteria are a

clinician-based assessment system that does not consider

the patients’ concerns or wishes. The criteria lack

objective grading and is open to subjective error. How

can a clinician decide whether a restoration needs to be

replaced because of surface roughness, margin colour or

surface colour, as long as its presence is not detrimental to

the remaining tooth structure? A degree of staining

acceptable to one patient may be unacceptable to

another and the decision to replace the restoration is

extremely patient and operator dependant. It is for this

reason that you have to question the value of a clinician-

based C assessment; we did not include one. Our criteria

attempted to eliminate this subjective bias and simply

determined whether a variable was present or not.

The assessment needed to be patient-focused and

evaluate the restorations from a patient-based perspec-

tive. With regard to the restorations, the patients’ main

concerns are whether the restoration stays on or not,

and whether the visible surfaces look acceptable. It is

for this reason that only the labial and incisal surfaces of

the restored teeth were assessed with regard to areas of

potential aesthetic concern (i.e. restoration staining,

marginal discolouration, colour match, surface rough-

ness and marginal adaptation). Even if the lingual

surface was stained, this is likely to be of no concern to

the patient and it is likely that a monitor and review

approach would be adopted.

Restoration performance

Loss of restorative volume was due to wear rather than

fractures as described by previous authors. This might be



due to the fact that the composite restorations were

placed in bulk rather than increments and thus elimin-

ating the potential for failure at these interfaces. The

delamination of indirect Artglass restorations has been

reported (9).

Eighty-six per cent the composite restorations exhib-

ited <10% loss of volume and 14% exhibited 50–90%

loss of volume. None of the patients received an

occlusal coverage splint following the re-establishment

of occlusal contacts. Theoretically, the use of a

protective occlusal splint might reduce the wear of the

composite restorations but the patient compliance with

wearing these appliances is questionable.

According to the examining clinicians, marginal

discolouration was evident in 57% of patients, but

only affected 26% of the remaining restorations.

None of the patients remarked on the staining and

none requested replacement or rectification. The

patients’ aesthetic acceptance of the restorations was

good. This might be because the mandibular anterior

teeth are less visible than the maxillary dentition so

that the stained margin is less visible than if it

affected the labial surface of the maxillary teeth. But,

it must be remembered that eight of the patients also

had maxillary composite restorations placed (50

restorations). If these had stained unacceptably, then

the patient could have had a more pessimistic view of

the mandibular restorations.

The restorations placed as ‘fixed Dahl appliances’

performed as well as those placed as part of a planned

treatment reorganizing the occlusion at an increased

occlusal vertical dimension. This is despite the theoret-

ical risk that the ‘Dahl’ restorations would be subject to

greater loading until re-establishment of posterior

occlusal contacts occurred. This is in agreement with

other adhesive ‘Dahl’ techniques. Chana et al. (15)

reported no difference in the performance of resin-

bonded gold alloy restorations irrespective of the

method employed for interocclusal space creation.

Comparison with other reports

This study has specifically assessed the performance of

direct composite restorations placed on worn mandibular

anterior teeth. Although the use of direct composite resin

for the management of the worn anterior dentition has

been reported previously (6, 7), comparison with our

results is not possible, as these studies do not differentiate

between maxillary and mandibular restorations.

If the performance of restorations placed on worn

maxillary teeth is compared with those placed on

mandibular teeth, a lower survival rate of the mandib-

ular restorations would be expected. The mandibular

teeth have a smaller bonding area and the restorations

are likely to experience greater shear and tensile forces

in protrusive guidance. Gow and Hemmings (9) repor-

ted no bulk failures of 75 Indirect Artglass restorations

placed on the palatal aspect of worn maxillary anterior

teeth at 2 years. Hemmings et al. (6) reported the bulk

failure of 7 out of 104 (7%) direct composite restora-

tions placed on the anterior dentition at 30 months.

This is similar to the figure of 6% at 2Æ5 years reported

in this study.

Circumferential preparation

This study questions the need for pre-operative tooth

preparation prior to the placement of direct composite

restorations. The presence of a circumferential pre-

paration and the ability to provide cervical extension

of the restorations did not statistically influence the

survival of the restorations. Admittedly, this might be

due to the medium-term results of the study and the

fact that few restorations have failed. The need for

cervical extension has been questioned in other

studies. Walls (16) reported a similar finding when

he assessed porcelain onlays with buccal cervical

extensions that were used to restore worn anterior

teeth with occlusal wear predominantly. Two out of

54 porcelain onlay restorations, followed up for a

minimum of 50 months, underwent partial loss of

material in the cervical region relatively early in the

life of the restoration. These restorations were then

essentially attached only to the flat dentine surfaces.

This suggests that extensions are not necessary to aid

retention of adhesively retained onlays. Chana et al.

(15) reported that the degree of coverage of posterior

resin-bonded gold alloy restorations had no influence

on survival. The onlay type of preparation had no

mechanical retentive features, other than approxi-

mately 1–2-mm chamfer on the axial surfaces, and

these performed as well as a three-quarter type

preparation.

There may be some situations where pre-operative

tooth preparation is advised. The use of a chamfer

margin can aid the technician as it provides a finish line

for constructing indirect restorations. An enamel bevel

might be advocated for aesthetic reason as it can



provide a better transition between the restorative

material and adjacent tooth structure.

Patient opinion

The majority of studies related to the restoration of worn

anterior teeth with this type of technique report a high

level of patient satisfaction (6, 7, 9). This study attempted

to provide greater objective data of the patients’ opinions

regarding the direct composite build-up technique.

Choice of composite system

A single layer composite system was used and patient

satisfaction of appearance was high. Herculite XRV

composite (hybrid composite) and Optibond (dentine

bonding agent) was used as there is some evidence that

it performs significantly better than Durafill (microfill

composite) bonded with Scotchbond Multipurpose

(dentine adhesive system) (6) in the TSL environment.

Other composite systems are available on the market,

which involve the incremental build-up of the restor-

ation using different shades and opacities of composite

resin. These materials may produce a more natural

aesthetic appearance; however, they involve greater

chair-side time because of the placement and curing of

multiple increments of composite rather than a bulk of

composite as described above. There is no clinical

evidence relating to how these materials perform in a

TSL situation. The high level of satisfaction of appear-

ance might be greater in TSL patients as there is often a

dramatic change from the pre-operative status. The

patients enjoy the overall improvement and are less

concerned about the minutiae of aesthetics.

Conclusion

Composite restorations are not the same as conven-

tional extra-coronal restorations and therefore have

their own distinct advantages and disadvantages.

Direct composite restorations have distinct biological

advantages compared with crowns and for the major-

ity of patients they perform well, offer a high degree of

patient satisfaction and require an acceptable level of

maintenance.

It can be concluded from this prospective clinical trial

that direct composite restorations placed at an increased

occlusal vertical dimension are a simple and time-

efficient method of managing the worn mandibular

anterior dentition. Pre-operative circumferential pre-

paration was not required to improve the restoration

survival or patient aesthetic satisfaction. The technique

did not have a detrimental effect on temporo-mandib-

ular joint, periodontal, pulpal or periapical health. The

placement of these restorations provided an improve-

ment in the aesthetics of the teeth, a reduction in the

concern over the longevity of the worn lower anterior

teeth, and improvements with regard to sensitivity

experienced with hot or cold foods or drinks. The

patient’s accommodation to the technique was good

and the results were accompanied with a high level of

patient satisfaction. Marginal breakdown and staining

was the more common form of deterioration of these

composite-based restorations. For the majority of

patients, this was not of concern. Bulk failure and

fracture were uncommon.

Acknowledgments

The authors would like to acknowledge Miss Kelly

Romeo and Mr Paul Kensit for their involvement in this

study.

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Correspondence: Neil J. Poyser, Department of Restorative Dentistry,

Maxillofacial Unit, Nottingham Univeristy Hospital NHS Trust.

Queen’s Medical Centre Campus. Derby Road, Nottingham. NG7

2UH, UK.

E-mail: [email protected]



Documents

The evaluation of direct composite restorations for the worn mandibular anterior dentition – clinical performance and patient satisfaction