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Performance of Intra-Oral Procedures that are Not Controlled Acts by Preventive Dental Assistants, Level II Dental Assistants and Registered Dental Hygienists

Approved by Council September 17, 2021

This Standard is intended to assist dentists in understanding their professional responsibilities when giving direction regarding the performance of an intra-oral procedure that is not a controlled act to ensure that patients are treated safely and competently. This Standard is also intended to assist dentists in understanding who may perform it.

Executive Summary

As the primary oral health care provider, a dentist is responsible for evaluating and addressing a patient’s comprehensive oral health care needs. In most instances, however, the delivery of dental services involves a team of oral health care professionals, working in collaboration to achieve a common goal: the provision of high quality oral health care to patients.

In a dental practice and under the dentist’s direction, dental assistants and registered dental hygienists with the requisite qualifications and competence are able to provide many dental services directly to patients, which facilitates these oral health care professionals performing to the full scope of their practice.

While all members of the oral health care team work together and each have their respective scopes of practice, the dentist has professional responsibilities to direct and coordinate the delivery of dental services to ensure that the patient’s experience is seamless, that dental services are performed safely and competently by the appropriate team member, and that the dentist is appropriately consulted, as required.

The procedures performed in a dental practice will encompass those defined in law as “controlled acts” and those that are not controlled acts.

This Standard is intended to assist dentists in understanding their professional responsibilities when giving direction regarding the performance of an intra-oral procedure that is not a controlled act to ensure that patients are treated safely and competently. This Standard is also intended to assist dentists in understanding who may perform it.

Standard of Practice

Performance of Controlled Acts

The Regulated Health Professions Act, 1991[1] (RHPA), restricts the performance of 14 specified “controlled acts”, such that no person is permitted to perform them in the course of providing health care services to an individual unless:

  • the person is a member authorized by a health profession Act to perform the controlled act; or
  • the performance of the controlled act has been delegated to the person by a member described in clause (a)[2].

In accordance with the Dentistry Act, 1991[3], dentists who are members of the College are authorized to perform 8 of the 14 controlled acts. However, the regulations made under the Dentistry Act, 1991, prevent dentists from delegating any of their controlled acts to anyone.

In accordance with the Dental Hygiene Act, 1991[4], dental hygienists who are members of the College of Dental Hygienists of Ontario (CDHO) are authorized to perform 3 controlled acts.

In Ontario, dental assistants are not regulated and are not authorized to perform any controlled acts.

Procedures that are Not Controlled Acts

Other intra-oral procedures that are not controlled acts, because they are not considered by the RHPA to expose patients to the risk of serious bodily harm, are considered to be in the “public domain”. These intra-oral procedures may be performed by regulated and non-regulated health professionals in a dentist’s practice, including Preventive Dental Assistants (“PDAs”), Level II Dental Assistants and Registered Dental Hygienists, provided the dentist fulfills their professional responsibilities, as outlined below.

Professional Responsibilities of Dentists

A dentist must maintain the standards of practice of the profession whenever they direct a person, such as a Preventive Dental Assistant, Level II Dental Assistant or Registered Dental Hygienist, to perform an intra-oral procedure for a patient. The dentist giving direction regarding an intra-oral procedure listed in this Standard is responsible for its performance and must:

  • have current knowledge about the patient in the context of a dentist-patient relationship;
  • have made a diagnosis or otherwise made a determination about a patient’s condition, before giving direction regarding an intra-oral procedure;
  • have considered the best interests of the patient to achieve an appropriate balance of patient need and access, such that the quality of care is not compromised;
  • have determined whether a person has the qualifications and competence to perform the intra-oral procedure for the patient;
  • have obtained the patient’s informed consent for the performance of the intra-oral procedure and for the person who will be performing it; and
  • provide the appropriate level of supervision to ensure that the intra-oral procedure is performed safely and competently, taking into account the specific intra-oral procedure being performed, the circumstances under which it will be performed, and the knowledge, skill and judgment of the person performing it.

The dentist giving direction regarding an intra-oral procedure listed in this Standard must ensure that the person who is being permitted to perform it has the qualifications and competence required by this Standard. The documentation (e.g. certificate, diploma) by which the dentist has made this determination must be maintained and available for inspection by a representative of the College, if requested.

The dentist giving direction regarding an intra-oral procedure listed in this Standard must provide the appropriate level of supervision. For some intra-oral procedures, on-site supervision by the dentist is required. For others, no supervision or supervision via technology may be appropriate. Unless specifically provided otherwise in this Standard, the dentist giving direction regarding an intra-oral procedure listed in this Standard must provide the appropriate level of supervision and ensure, prior to the patient’s discharge, that it was performed safely and competently.

This Standard provides lists of those intra-oral procedures that are not controlled acts, and that dentists may permit Preventive Dental Assistants, Level II Dental Assistants and Registered Dental Hygienists to perform in their practice.

Dental assistants who are not Preventive Dental Assistants or Level II Dental Assistants do NOT have the qualifications and competence, and must NOT be permitted to perform any of the following intra-oral procedures.

Preventive Dental Assistants

A Preventive Dental Assistant is a person who has successfully completed a Preventive Dental Assistant program from a College of Applied Arts and Technology in Ontario or other course(s) approved by the Council of the College, and who was listed as a Preventive Dental Assistant by the College prior to January 1, 2000.

A dentist may give direction to a Preventive Dental Assistant to perform any of the following intra-oral procedures:

(1)   application and removal of rubber dam;

(2)   mechanical polishing of the coronal portion of the teeth, but not including any instrumentation;

(3)   taking extra-/intra-oral photographs;

(4)   taking alginate impressions of the teeth for study and working models;

(5)   taking digital/optical impressions of the teeth for study and working models;

(6)   oral hygiene instruction;

(7)   dietary counselling relative to dentistry; and

(8)   fluoride application.

For the intra-oral procedure numbered (1) above, specifically the application and removal of rubber dam, the dentist giving direction to a Preventive Dental Assistant to perform this procedure must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

For the intra-oral procedures numbered (2), (3), (4), (5), (6), (7) and (8) above, the dentist giving direction to a Preventive Dental Assistant to perform any of these procedures may permit the Preventive Dental Assistant to perform it unsupervised.

Level II Dental Assistants

A Level II Dental Assistant is a person who holds the certificate of the National Dental Assisting Examining Board issued on or before December 31, 2002, or who holds a certificate of the National Dental Assisting Examining Board issued after December 31, 2002 provided that the certificate was issued based upon successful completion of its examination(s).

A dentist may give direction to a Level II Dental Assistant to perform any of the following intra-oral procedures:

(1)   application and removal of rubber dam;

(2)   mechanical polishing of the coronal portion of the teeth, but not including any instrumentation;

(3)   taking extra-/intra-oral photographs;

(4)   taking alginate impressions of the teeth for study and working models;

(5)   taking digital/optical impressions of the teeth for study and working models;

(6)   oral hygiene instruction;

(7)   dietary counselling relative to dentistry;

(8)   fluoride application;

(9)   application of materials topically to prepare the surface of the teeth for pit and fissure sealants;

(10) application of pit and fissure sealants;

(11) application of topical anesthetics;

(12) application of desensitizing agents;

(13) polishing restorations;

(14) oral irrigation;

(15) whitening the coronal portion of the teeth using tray-based systems and materials generally available to the public without prescription;

(16) placing and removing restorative matrix bands and wedges;

(17) public health screenings to detect gross abnormalities[5];

(18) removing periodontal dressings that are uncomplicated[6]; and

(19) removing simple interrupted sutures[7].

For the intra-oral procedures numbered (1), (9), (10), (11), (12), (13), (16), (18) and (19) above, the dentist giving direction to a Level II Dental Assistant to perform any of these procedures must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

For the intra-oral procedures numbered (2), (3), (4), (5) (6), (7), (8), (14), (15) and (17) above, the dentist giving direction to a Level II Dental Assistant to perform any of these procedures may permit the Level II Dental Assistant to perform it unsupervised.

In addition to the intra-oral procedures listed above, a Level II Dental Assistant who has successfully completed a Supplemental Course in Orthodontic Procedures that meets the criteria listed in Appendix 1 may also perform any of the following four intra-oral procedures:

(1)   placing and cementing bands, brackets and passive space-maintaining or orthodontic appliances that have been previously selected, fitted and/or dispensed by a dentist for orthodontic purposes[8];

(2)   placing attachments for orthodontic purposes in conjunction with clear aligner therapy;

(3)   removing bands, brackets and passive space-maintaining or orthodontic appliances, but not removing cement and/or bonding resin[9]; and

(4)   taking non-alginate conventional impressions for working models for the fabrication of space-maintaining or orthodontic appliances.

For the intra-oral procedures numbered (1), (2), (3) and (4) above, the dentist giving direction to a Level II Dental Assistant to perform any of these procedures must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

In addition to the intra-oral procedures listed above, a Level II Dental Assistant who has successfully completed a Supplemental Course in Restorative Procedures that meets the criteria listed in Appendix 2 may also perform any of the following 5 intra-oral procedures:

(1)   taking digital/optical impressions for working models, including prepared teeth[10];

(2)   taking non-alginate conventional impressions for working models, including prepared teeth[11];

(3)   taking interocclusal records or bite registrations using non-rigid materials;

(4)   taking facebow transfer records;

(5)   fabricating single unit temporary crowns, including intra-orally, to be fitted and cemented by a dentist[12].

For the intra-oral procedures numbered (1), (2) and (5) above, the dentist giving direction to a Level II Dental Assistant to perform any of these procedures must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

For the intra-oral procedure numbered (3) and (4) above, the dentist giving direction to a Level II Dental Assistant to perform any of these procedures may permit the Level II Dental Assistant to perform it unsupervised.

Registered Dental Hygienists

A Registered Dental Hygienist is a person who is a member of the College of Dental Hygienists of Ontario.

A dentist may give direction to a Registered Dental Hygienist to perform any of the following intra-oral procedures[13]:

(1)   application and removal of rubber dam;

(2)   mechanical polishing of the coronal portion of the teeth;

(3)   taking extra-/intra-oral photographs;

(4)   taking alginate impressions of the teeth for study and working models;

(5)   taking digital/optical impressions of the teeth for study and working models;

(6)   oral hygiene instruction;

(7)   dietary counselling relative to dentistry;

(8)   fluoride application;

(9)   application of materials topically to prepare the surface of the teeth for pit and fissure sealants;

(10) application of pit and fissure sealants;

(11) application of topical anesthetics;

(12) application of desensitizing agents;

(13) polishing restorations;

(14) oral irrigation;

(15) whitening the coronal portion of the teeth using tray-based and other systems;

(16) placing and removing restorative matrix bands and wedges;

(17) public health screenings to detect gross abnormalities;

(18) applying periodontal dressings;

(19) removing periodontal dressings that are uncomplicated[14];

(20) removing simple interrupted sutures[15];

(21) placing and cementing bands, brackets and passive space-maintaining or orthodontic appliances that have been previously selected, fitted and/or dispensed by a dentist for orthodontic purposes[16];

(22) placing attachments for orthodontic purposes in conjunction with clear aligner therapy;

(23) removing bands, brackets and passive space-maintaining or orthodontic appliances[17];

(24) taking non-alginate conventional impressions for working models for the fabrication of space-maintaining or orthodontic appliances;

(25) taking digital/optical impressions for working models, including prepared teeth[18];

(26) taking non-alginate conventional impressions for working models, including prepared teeth[19];

(27) taking interocclusal records or bite registrations using non-rigid materials;

(28) taking facebow transfer records; and

(29) fabricating single unit temporary crowns, including intra-orally, to be fitted and cemented by a dentist[20].

For the intra-oral procedures numbered (24), (25), (26) and (29) above, the dentist giving direction to a Registered Dental Hygienist to perform any of these procedures must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

For the intra-oral procedure numbered (19) and (20) above, specifically removing periodontal dressings that are uncomplicated and removing simple interrupted sutures, the dentist giving direction to a Registered Dental Hygienist to perform these procedures must provide supervision via technology or be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently.

For the intra-oral procedure numbered (1) to (18), (21), (22), (23), (27) and (28) above, the dentist giving direction to a Registered Dental Hygienist to perform any of these procedures may permit the Registered Dental Hygienist to perform it unsupervised. 

Summary of Controlled Acts for Dentists and Dental Hygienists

The RHPA restricts the performance of 14 specified “controlled acts”, such that no person is permitted to perform them in the course of providing health care services to an individual unless:

  1. the person is a member authorized by a health profession Act to perform the controlled act; or
  2. the performance of the controlled act has been delegated to the person by a member described in clause (a).

In accordance with the Dentistry Act, 1991, dentists who are members of the Royal College of Dental Surgeons of Ontario (RCDSO) are authorized to perform the following controlled acts in the course of engaging in the practice of dentistry:

(1) Communicating a diagnosis identifying a disease or disorder of the oral-facial complex as the cause of a person’s symptoms.

(2) Performing a procedure on tissue of the oral-facial complex below the dermis, below the surface of a mucous membrane or in or below the surfaces of the teeth, including the scaling of teeth.

(3) Harvesting tissue for the purpose of surgery on the oral-facial complex.

(4) Setting a fracture of a bone of the oral-facial complex or setting a dislocation of a joint of the oral-facial complex.

(5) Administering a substance by injection or inhalation.

(6) Applying or ordering the application of a prescribed form of energy.

(7) Prescribing, dispensing or compounding a drug.

(7.1) Selling a drug in accordance with the regulations.

(8) Fitting or dispensing a dental prosthesis, or an orthodontic or periodontal appliance or a device used inside the mouth to protect teeth from abnormal functioning.

In accordance with the Dental Hygiene Act, 1991, dental hygienists who are members of the College of Dental Hygienists of Ontario (CDHO) are authorized to perform the following controlled acts in the course of engaging in the practice of dental hygiene:

  1. Scaling teeth and root planing including curetting surrounding tissue.
  2. Orthodontic and restorative procedures.
  3. Prescribing, dispensing, compounding or selling a drug designated in the regulations.

Registered Dental Hygienists may perform scaling and root planing on their own initiative, provided that certain conditions are met, or alternatively with an order of a dentist. They may also prescribe some drugs (e.g. chlorhexidine and its salts) on their own initiative, provided that certain conditions are met. However, Registered Dental Hygienists may only perform orthodontic and restorative procedures with an order of a dentist.

In addition to the intra-oral procedures listed in this Standard, Registered Dental Hygienists may also perform, with an order from a dentist, the following orthodontic procedures:

  • separating teeth for orthodontic purposes; and
  • placing and removing arch wires and active orthodontic appliances that have been previously selected, fitted and/or dispensed by a dentist for orthodontic purposes.

In addition to the intra-oral procedures listed in this Standard, Registered Dental Hygienists who hold a specialty certificate of registration may also perform, with an order from a dentist, the following restorative procedures:

  • placing and finishing amalgam, glass ionomer and composite resin restorations;
  • placing cavity liners in a tooth where the pulp has not been exposed;
  • cementing temporary crowns previously fitted by a dentist;
  • placing temporary fillings.

The dentist providing authorization to perform any of the orthodontic or restorative procedures listed above must be present in the office suite while it is being performed and ensure, prior to the patient’s discharge, that it was performed safely and competently. 

Appendix 1

Supplemental Course in Orthodontic Procedures for Level II Dental Assistants

A supplemental course in orthodontic procedures for Level II Dental Assistants means a course that:

  • is provided at a faculty of dentistry or school of dentistry at a university in Canada, an accredited college of applied arts and technology in Ontario or at such other educational facility in Canada equivalent thereto;
  • is provided under the direction of a dentist who is licensed or registered as a specialist in orthodontics and dentofacial orthopedics in the Canadian jurisdiction in which the course is provided;
  • contains a didactic component which teaches the theoretical information required in order to understand the nature of the 4 intra-oral orthodontic procedures listed in this Standard;
  • contains a clinical component which teaches the 4 intra-oral orthodontic procedures listed in this Standard and which component is supervised by a dentist who is licensed or registered as a specialist in orthodontics and dentofacial orthopedics in the Canadian jurisdiction in which the course is provided;
  • includes evaluation components of each of the didactic and clinical components of the course so as to determine whether the person is able to perform the 4 intra-oral orthodontic procedures listed in this Standard safely and competently;
  • provides for the issuance of a certificate signed by the course director, attesting to the fact that the person has successfully completed a course of study which includes the components set out in clauses (a), (b), (c), (d) and (e) of this paragraph.

Appendix 2

Supplemental Course in Restorative Procedures for Level II Dental Assistants

A supplemental course in restorative procedures for Level II Dental Assistants means a course that:

(a)    is provided at a faculty of dentistry or school of dentistry at a university in Canada, an accredited college of applied arts and technology in Ontario or at such other educational facility in Canada equivalent thereto;

(b)   is provided under the direction of a dentist who is licensed or registered in the Canadian jurisdiction in which the course is provided;

(c)    contains a didactic component which teaches the theoretical information required in order to understand the nature of the 5 intra-oral restorative procedures listed in this Standard;

(d)   contains a clinical component which teaches the 5 intra-oral restorative procedures listed in this Standard and which component is supervised by a dentist who is licensed or registered in the Canadian jurisdiction in which the course is provided;

(e)    includes evaluation components of each of the didactic and clinical components of the course so as to determine whether the person is able to perform the 5 intra-oral restorative procedures listed in this Standard safely and competently;

(f)    provides for the issuance of a certificate signed by the course director, attesting to the fact that the person has successfully completed a course of study which includes the components set out in clauses (a), (b), (c), (d) and (e) of this paragraph.

Appendix 3

Summary Chart of Intra-Oral Procedures

Intra-Oral Procedure

Preventive Dental Assistant

Level II Dental Assistant

Registered Dental Hygienist

Application and removal of rubber dam

Mechanical polishing of the coronal portion of the teeth, but not including any instrumentation

Taking extra-/intra-oral photographs

Taking alginate impressions of the teeth for study and working models

Taking digital/optical impressions of the teeth for study and working models

Oral hygiene instruction

Dietary counselling relative to dentistry

Fluoride application

Application of materials topically to prepare the surface of the teeth for pit and fissure sealants

 

Application of pit and fissure sealants

 

Application of topical anaesthetics

 

Application of desensitizing agents

 

Polishing restorations

 

Oral irrigation

 

Whitening the coronal portion of the teeth

 

See note 1

See note 2

Placing and removing restorative matrix bands and wedges

 

Public health screenings to detect gross abnormalities

 

Applying periodontal dressings

 

 

Removing periodontal dressings that are uncomplicated

 

Removing simple interrupted sutures

 

Placing and cementing bands, brackets and passive space-maintaining or orthodontic appliances that have been previously selected, fitted and/or dispensed by a dentist for orthodontic purposes

 

Placing attachments for orthodontic purposes in conjunction with clear aligner therapy

 

Removing bands, brackets and passive space-maintaining or orthodontic appliances

 

See note 3

Taking non-alginate conventional impressions for working models for the fabrication of space-maintaining or orthodontic appliances

 

Taking digital/optical impressions  for working models, including prepared teeth

 

Taking non-alginate conventional impressions for working models, including prepared teeth

 

Taking interocclusal records or bite registrations using non-rigid materials

 

Taking facebow transfer records

 

Fabricating single unit temporary crowns, including intra-orally, to be fitted and cemented by a dentist

 


Legend

  • GREEN = no supervision required
  • YELLOW = supervision by dentist via technology or present in the office suite
  • ORANGE = supervision by dentist present in the office suite
Notes  
  1. Whitening the coronal portion of the teeth using tray-based systems and materials generally available to the public without prescription.
  2. Whitening the coronal portion of the teeth using tray-based and other systems.
  3. Removing bands, brackets and passive space-maintaining or orthodontic appliances, but not removing cement and/or bonding resin. 

Footnotes

[1] S.O. 1991, c. 18.

[2] The delegation of a controlled act by a member must be in accordance with any applicable regulations under the health profession Act governing the member’s profession. In addition, there are exceptions to the restriction on who can perform a controlled act, which exceptions are set out in the RHPA.

[3] S.O. 1991, c. 24.

[4] S.O. 1991, c. 22.

[5] Public health screenings to detect gross abnormalities are normally performed with a mirror and light. A Level II Dental Assistant may require appropriate training by a public health dentist to perform this intra-oral procedure for a patient safely and competently.

[6] The removal of periodontal dressings may be complicated, especially when non-resorbable continuous sutures have been placed. The performance of this procedure is limited to those instances in which it can be reasonably anticipated that the removal of the periodontal dressing will not be complicated, such as when resorbable sutures or non-resorbable interrupted sutures have been placed, which should be recorded in the patient’s record at the time the sutures are placed.

[7] The removal of sutures may be complicated, especially when continuous sutures have been placed or any other advanced suturing technique has been used. The performance of this procedure is limited to the removal of simple interrupted sutures that can be removed entirely from above the dermis or the surface of a mucous membrane.

[8] This intra-oral procedure does not include separating teeth for orthodontic purposes or placing and removing arch wires and active orthodontic appliances, which are controlled acts.

[9] When removing bands and brackets, this intra-oral procedure includes removing passive arch wires at the same appointment. Following the removal of bands, brackets and passive space-maintaining or orthodontic appliances, the subsequent removal of cement and/or bonding resin necessitates instrumentation that, if performed inappropriately, may result in the removal of tooth tissue. When giving direction regarding this intra-oral procedure, dentists may NOT permit Level II Dental Assistants to remove cement and/or bonding resin.

[10] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).

[11] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).

[12] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).

[13] These intra-oral procedures are in addition to those authorized to be performed by registered dental hygienists on their own initiative or pursuant to an “order” of a dentist, as more particularly described in the Dental Hygiene Act, 1991.

[14] The removal of periodontal dressings may be complicated, especially when non-resorbable continuous sutures have been placed. The performance of this procedure is limited to those instances in which it can be reasonably anticipated that the removal of the periodontal dressing will not be complicated, such as when resorbable sutures or non-resorbable interrupted sutures have been placed, which should be recorded in the patient’s record at the time the sutures are placed.

[15] The removal of sutures may be complicated, especially when continuous sutures have been placed or any other advanced suturing technique has been used. The performance of this procedure is limited to the removal of simple interrupted sutures that can be removed entirely from above the dermis or the surface of a mucous membrane.

[16] This intra-oral procedure does not include separating teeth for orthodontic purposes or placing and removing arch wires and active orthodontic appliances, which are controlled acts. Registered Dental Hygienists may perform these controlled acts with an order of a dentist. See Summary of Controlled Acts for Dentists and Dental Hygienists.

[17] When removing bands and brackets, this intra-oral procedure includes removing passive arch wires at the same appointment. Following the removal of bands, brackets and passive space-maintaining or orthodontic appliances, the subsequent removal of cement and/or bonding resin necessitates instrumentation that, if performed inappropriately, may result in the removal of tooth tissue. When giving direction regarding this intra-oral procedure, dentists may permit Registered Dental Hygienists who hold a general certificate of registration to use hand instruments and low-speed handpieces to remove cement and/or bonding resin. Dentists may permit Registered Dental Hygienists who hold a specialty certificate of registration to use hand instruments and low-speed/high-speed handpieces to remove cement and/or bonding resin.

[18] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, but may include the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).

[19] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, but may include the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).

[20] This intra-oral procedure does NOT include any instrumentation that involves the removal of tooth tissue, but may include the placement and/or removal of retraction cord, and/or the use of chemical agents (e.g. hemostatic agents).