Skip to content

Orthodontic Patient Experience of Intraoral Scans Versus Alginate Impressions

Orthodontic Patient Experience of Intraoral Scanners Versus Alginate Impressions in the UK: a Single-Centre Randomised Controlled Crossover Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05194956
Acronym
OPESI
Enrollment
86
Registered
2022-01-18
Start date
2022-05-31
Completion date
2023-01-03
Last updated
2025-03-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Orthodontic Patient Experience

Keywords

Orthodontic Patient, Intraoral Scan, Alginate impression, Conventional impression, Digital scan, Patient experience, Patient comfort, Preference

Brief summary

CONTEXT: Digital scanning systems are becoming more and more popular with the advent of the COVID-19 pandemic. The risks surrounding aerosol-generating procedures (AGP) has resulted in practitioners changing their normal practice and finding alternative methods to continue managing their patients. Digital (intraoral) scanners are often used to show patients treatment options and help in educating them regarding their oral hygiene as it produces an almost instant digital image of their teeth. Conventional methods using alginate impressions produce study models which are created in dental plaster or stone, involving a lab cost and a greater environmental impact but remain a popular method of recording a patient's teeth and bite. OBJECTIVE: To investigate patient experience, operator experience and preference in intraoral scanning versus alginate impression taking in the orthodontic setting. DESIGN, SETTING AND SUBJECTS: A randomised controlled two-period crossover trial to be conducted in a UK secondary care setting involving 84 participants ready to start orthodontic treatment, with no experience of impressions/intraoral scans in the last 2 years. Patients with cleft lip and/or palate or recent research involvement will be excluded. OUTCOMES: A modified visual analogue scale, will be used to measure patient and operator reported outcomes (e.g. patient comfort, operator confidence, perceived time taken and induction of cough/gag reflex) following an alginate impression or an intraoral scan using Trios® 3 intraoral scanner (3Shape). The time taken for each procedure will also be measured. Lastly, operator preference will be recorded. CONCLUSION: The proposed study aims to add to the limited evidence base, providing information regarding the use of intraoral scanners compared to alginate impressions from both the orthodontic patient and operator perspectives.

Detailed description

Eligible patients are to be identified during a virtual dental health education (DHE) appointment prior to their orthodontic treatment commencing. With consent, the trial will be discussed with patients meeting the inclusion criteria and they will be provided with relevant trial information in both leaflet and video format. The potential participant and/or their parent or guardian will be allowed time (3 weeks) to consider the information and ask any relevant questions. If they choose to take part in the trial, they will be recruited and allocated randomly into mixed block sizes using an online randomisation tool. If they choose not to participate, normal orthodontic care will continue. For children, unable to consent for themselves, assent will also be sought. Once the participant has provided appropriate consent/assent, the following procedure will be followed: • One unit will be set up with an operator and a nurse Participants in the alginate impression group: 1. The unit the participant will be treated in, will be set up appropriately with relevant materials ready. * The alginate to be used will be: Zhermack orthoprint® orthodontic alginate material 2. A timer will be started when the participant is seated in the chair 3. The operator will carry out the impression as normal: * Tray selection * Alginate mixing * Tray seating * Alginate setting * Tray removal * Wax bite * Clean up of the participant's face 4. The timer will be stopped 5. Questionnaires * Participant will be asked to complete a questionnaire (modified VAS using pictorial anchors) * Operator will be asked to complete a questionnaire 6. These will be collected for analysis 7. The participant will then have records taken as part of their normal orthodontic care, if not done already +/- a discussion to consent patient for orthodontic treatment 8. The participants will return a minimum 4 weeks later for a second appointment (if they have not had an intraoral scan already) in which they will undertake the process for 'Participants in the intraoral scanner group' Participants in the intraoral scanner group: 1. The unit the participant will be treated in, will be set up appropriately with relevant materials ready. The interchangeable covering will be placed over the scanner ready for use. * The intraoral scanning device to be used will be: Trios® 3 intraoral scanner (3Shape) * The staff will be appropriately trained and will be requested to carry out a minimum of 10 scans prior to the study beginning 2. A timer will be started when the participant is seated in the chair 3. The scan will be carried out as per the manufacturer's directions to include a full mouth scan and bite registration and saved on the scanner system. 4. The timer will be stopped 5. Questionnaires * Participant will be asked to complete a questionnaire (modified VAS using pictorial anchors) * Operator will be asked to complete a questionnaire 6. These will be collected for analysis 7. The participant will then have records taken as part of their normal orthodontic care, if not done already +/- a discussion to consent patient for orthodontic treatment +/- fit of any orthodontic appliance required. 8. The participants will return a minimum 4 weeks later for a second appointment (if they have not had an alginate impression already) in which they will undertake the process for 'Participants in the alginate impression group' A minimum of 4 weeks between the two appointments allows for an adequate washout period and it also fits with orthodontic laboratory work timelines within the hospital. Once all participant data is obtained, the operators will be asked a single question to indicate their preference towards a single method. Any participant and/or their parent or guardian, if appropriate who wishes to withdraw at any point during the trial can do so without reason and without this affecting or prejudicing the delivery of their orthodontic care. Analyses: * Primary outcome - the difference between the paired visual analogue scale (VAS) scores will be compared using analysis of variance (ANOVA) that will analyse the period, treatment and sequence effects of the comfort scores. * Secondary outcomes - the 8 secondary outcomes measured by VAS and the time taken to make the impression or complete the scan will be compared using analyses of variance suitable for a crossover study, that will test the period, treatment and sequence effects on these nine secondary outcomes. The operator's preference will be reported using descriptive statistics. The frequency and percentages will be recorded. Only the primary analysis will be compared against a specific level of significance. The secondary analyses should be considered as hypothesis generating rather than providing firm conclusions.

Interventions

An intraoral scan is multiple images taken using an intraoral scanning device which results in a digital mould being taken of the participants mouth and bite. It works by systematically placing the scanner tip over the teeth and gums, whilst it constructs an image on screen.

PROCEDUREAlginate impressions

Alginate impressions are the conventional method of creating dental moulds for orthodontic records. A plastic tray is filled with an alginate material, which is placed into the mouth to take a mould of the teeth. This requires two moulds for both top and bottom arches. In addition, the participant would also bite into a warm piece of wax to record their bite.

Sponsors

British Orthodontic Society Foundation
CollaboratorUNKNOWN
Derby Pump Priming Charitable Funds
CollaboratorUNKNOWN
Derby Clinical Trials Support Unit
CollaboratorUNKNOWN
University Hospitals of Derby and Burton NHS Foundation Trust
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Intervention model description

Single-centre prospective randomised controlled two-period crossover study

Eligibility

Sex/Gender
ALL
Age
10 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* New patients, aged 10 years and old, attending the Royal Derby Hospital orthodontic department, requiring study model impressions taken prior to commencing orthodontic treatment * Participants must be capable of giving informed consent, or have an acceptable individual capable of giving consent on the patient's behalf (e.g. parent or guardian of a child under 16 years of age).

Exclusion criteria

* Patients who have had previous experience of impressions/intraoral scans in the last 2 years * Cleft lip and/or palate patients * Patient who have been involved in a study in the last 6 months or are currently part of a study

Design outcomes

Primary

MeasureTime frameDescription
Orthodontic Patient ComfortImmediately following interventionA 100mm modified Visual Analogue Scale (VA scale) measuring patient comfort during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Secondary

MeasureTime frameDescription
Relative Speed of ImpressionImmediately following interventionA 100mm modified Visual Analogue Scale (VA scale) measuring relative speed during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Nausea and/or CoughingImmediately following interventionA 100mm modified Visual Analogue Scale (VA scale) measuring nausea and/or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Likely RecommendationImmediately following interventionA 100mm modified Visual Analogue Scale (VA scale) measuring likely recommendation and/or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Ease of Impression for the OperatorImmediately following interventionA 100mm Visual Analogue Scale (VA scale) measuring ease of impression for the operator during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Experience of PainImmediately following interventionA 100mm modified Visual Analogue Scale (VA scale) measuring pain during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Relative Speed of Impression for the OperatorImmediately following interventionA 100mm Visual Analogue Scale (VA scale) measuring relative speed of impression for the operator during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100
Operator Experience of Sickness or CoughingImmediately following interventionA 100mm Visual Analogue Scale (VA scale) measuring operator experience of sickness or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more positive experience. Minimum value: 0, Maximum value: 100
Chairside Time Taken to Complete Impression MethodImmediately following interventionA quantitative time measure will be recorded for each impression method
Operator PreferenceImmediately following completion of participant data collectionA simple question to determine operator preference for intraoral scanning versus alginate impressions.
Confidence Taking the Impression for the OperatorImmediately following interventionA 100mm Visual Analogue Scale (VA scale) measuring operator confidence during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Countries

United Kingdom

Participant flow

Participants by arm

ArmCount
Arm 1 - Alginate Impressions Followed by Digital Intraoral Scan
The participant will have alginate impressions taken for orthodontic treatment records first. Followed by a digital intraoral scan a minimum of 4-6 weeks washout period. After each intervention, the participant will complete a modified visual analogue scale (VAS) questionnaire about their experience. Intraoral scan: An intraoral scan is multiple images taken using an intraoral scanning device which results in a digital mould being taken of the participants mouth and bite. It works by systematically placing the scanner tip over the teeth and gums, whilst it constructs an image on screen. Alginate impressions: Alginate impressions are the conventional method of creating dental moulds for orthodontic records. A plastic tray is filled with an alginate material, which is placed into the mouth to take a mould of the teeth. This requires two moulds for both top and bottom arches. In addition, the participant would also bite into a warm piece of wax to record their bite.
42
Arm 2 - Digital Intraoral Scan Followed by Alginate Impressions
The participant will have a digital intraoral taken for orthodontic treatment records first. Followed by alginate impressions a minimum of 4-6 weeks washout period. After each intervention, the participant will complete a modified visual analogue scale (VAS) questionnaire about their experience. Intraoral scan: An intraoral scan is multiple images taken using an intraoral scanning device which results in a digital mould being taken of the participants mouth and bite. It works by systematically placing the scanner tip over the teeth and gums, whilst it constructs an image on screen. Alginate impressions: Alginate impressions are the conventional method of creating dental moulds for orthodontic records. A plastic tray is filled with an alginate material, which is placed into the mouth to take a mould of the teeth. This requires two moulds for both top and bottom arches. In addition, the participant would also bite into a warm piece of wax to record their bite.
42
Total84

Withdrawals & dropouts

PeriodReasonFG000FG001
Washout PeriodWithdrawal by Subject02

Baseline characteristics

CharacteristicArm 1 - Alginate Impressions Followed by Digital Intraoral ScanArm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsTotal
Age, Continuous14.3 years
STANDARD_DEVIATION 4.23
14.1 years
STANDARD_DEVIATION 3.1
14.2 years
STANDARD_DEVIATION 3.69
Race/Ethnicity, Customized
Ethnicity
Black African
0 Participants1 Participants1 Participants
Race/Ethnicity, Customized
Ethnicity
Black Caribbean
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Ethnicity
Indian
2 Participants1 Participants3 Participants
Race/Ethnicity, Customized
Ethnicity
Mixed heritage
3 Participants3 Participants6 Participants
Race/Ethnicity, Customized
Ethnicity
Not given
2 Participants2 Participants4 Participants
Race/Ethnicity, Customized
Ethnicity
Pakistani
4 Participants3 Participants7 Participants
Race/Ethnicity, Customized
Ethnicity
White
30 Participants32 Participants62 Participants
Region of Enrollment
United Kingdom
42 participants42 participants84 participants
Sex: Female, Male
Female
21 Participants23 Participants44 Participants
Sex: Female, Male
Male
21 Participants19 Participants40 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 840 / 86
other
Total, other adverse events
0 / 840 / 86
serious
Total, serious adverse events
0 / 840 / 86

Outcome results

Primary

Orthodontic Patient Comfort

A 100mm modified Visual Analogue Scale (VA scale) measuring patient comfort during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanOrthodontic Patient Comfort9.2 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsOrthodontic Patient Comfort7.7 score on a scale
Comparison: All units of measure reported for this analysis are the mean within-patient differences between alginate and scan VAS scores (i.e. alginate score - scan score)p-value: 0.000695% CI: [3.75, 13.15]Two-period two-treatment crossover ANOVA
p-value: 0.1984ANOVA
p-value: 0.7494ANOVA
p-value: 0.00195% CI: [-21.29, -5.33]Mixed Models Analysis
Secondary

Chairside Time Taken to Complete Impression Method

A quantitative time measure will be recorded for each impression method

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanChairside Time Taken to Complete Impression Method-88.8 seconds (within-patient)
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsChairside Time Taken to Complete Impression Method-151.1 seconds (within-patient)
p-value: <0.0000595% CI: [-149.54, -90.38]Two-period two-treatment crossover ANOVA
p-value: 0.8509ANOVA
p-value: 0.0355ANOVA
Secondary

Confidence Taking the Impression for the Operator

A 100mm Visual Analogue Scale (VA scale) measuring operator confidence during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanConfidence Taking the Impression for the Operator-1.9 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsConfidence Taking the Impression for the Operator-2.6 score on a scale
p-value: 0.134795% CI: [-5.17, 0.69]Two-period two-treatment crossover ANOVA
p-value: 0.9259ANOVA
p-value: 0.8225ANOVA
Secondary

Ease of Impression for the Operator

A 100mm Visual Analogue Scale (VA scale) measuring ease of impression for the operator during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanEase of Impression for the Operator-1.6 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsEase of Impression for the Operator-8.8 score on a scale
p-value: 0.081795% CI: [-11.12, 0.69]Two-period two-treatment crossover ANOVA
p-value: 0.091ANOVA
p-value: 0.2278ANOVA
Secondary

Experience of Pain

A 100mm modified Visual Analogue Scale (VA scale) measuring pain during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanExperience of Pain-3.5 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsExperience of Pain-3.3 score on a scale
p-value: 0.12395% CI: [-7.71, 0.91]Two-period two-treatment crossover ANOVA
p-value: 0.8423ANOVA
p-value: 0.9544ANOVA
Secondary

Likely Recommendation

A 100mm modified Visual Analogue Scale (VA scale) measuring likely recommendation and/or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanLikely Recommendation6.4 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsLikely Recommendation4.1 score on a scale
p-value: 0.014695% CI: [1.09, 9.46]Two-period two-treatment crossover ANOVA
p-value: 0.5911ANOVA
p-value: 0.5825ANOVA
Secondary

Nausea and/or Coughing

A 100mm modified Visual Analogue Scale (VA scale) measuring nausea and/or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanNausea and/or Coughing12.6 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsNausea and/or Coughing6.7 score on a scale
p-value: 0.021395% CI: [1.5, 17.79]Two-period two-treatment crossover ANOVA
p-value: 0.1583ANOVA
p-value: 0.4709ANOVA
Secondary

Operator Experience of Sickness or Coughing

A 100mm Visual Analogue Scale (VA scale) measuring operator experience of sickness or coughing during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more positive experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanOperator Experience of Sickness or Coughing-26.9 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsOperator Experience of Sickness or Coughing-19.6 score on a scale
p-value: <0.0000595% CI: [-30.71, -15.75]Two-period two-treatment crossover ANOVA
p-value: 0.1369ANOVA
p-value: 0.3366ANOVA
Secondary

Operator Preference

A simple question to determine operator preference for intraoral scanning versus alginate impressions.

Time frame: Immediately following completion of participant data collection

Population: This involved asking the 4 operators (clinicians) their overall preference for alginate impressions or intraoral scans during the clinical trial.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanOperator Preference3 Participants
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsOperator Preference1 Participants
Secondary

Relative Speed of Impression

A 100mm modified Visual Analogue Scale (VA scale) measuring relative speed during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanRelative Speed of Impression-3.5 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsRelative Speed of Impression-3.4 score on a scale
p-value: 0.043995% CI: [-6.69, -0.12]Two-period two-treatment crossover ANOVA
p-value: 0.3878ANOVA
p-value: 0.9772ANOVA
Secondary

Relative Speed of Impression for the Operator

A 100mm Visual Analogue Scale (VA scale) measuring relative speed of impression for the operator during intraoral scanning taking versus alginate impressions taken in the orthodontic setting. A higher score would indicate a more negative experience. Minimum value: 0, Maximum value: 100

Time frame: Immediately following intervention

ArmMeasureValue (MEAN)
Arm 1 - Alginate Impressions Followed by Digital Intraoral ScanRelative Speed of Impression for the Operator-8.1 score on a scale
Arm 2 - Digital Intraoral Scan Followed by Alginate ImpressionsRelative Speed of Impression for the Operator-14.2 score on a scale
p-value: 0.0295% CI: [-20.47, -1.83]Two-period two-treatment crossover ANOVA
p-value: 0.9104ANOVA
p-value: 0.5194ANOVA

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026