Esthetic dentistry

3 Clinical CEU’s

Compiled by Mrs C Brent (DiplOH US, EF UWC)

The demand for a more beautiful smile has never been higher than now. Society is bombarded with

beauty and technology has given us the tools and know how to realise almost everyone’s beauty

dreams.

But what is beauty?

It has been described as a combination of qualities, such as shape, colour, or form that pleases the

aesthetic senses, especially the sight. Some say true beauty comes from the inside. Being

compassionate and having good character are virtuous traits and society needs to stop telling us

differently. ... Not only speaking of doing good things but having your actions match your words is

beauty. Having a gentle and kind heart is beauty.[1] Others say beauty is in the eye of the beholder.

We all know we shouldn’t judge people based on their looks. Beauty is only skin-deep, as the saying

goes. Moreover, someone’s appearance doesn’t tell us anything about how kind they are. Or how

dependable. Or anything else about their personality. [3]

But it’s hard to ignore the way a person looks. Something about attractive people makes us want to

watch them. We can’t take our eyes off a good-looking actor, actress or model. As such, beauty has

power over us. But what is beauty?

There is no simple answer. Researchers have, however, begun probing how beauty affects the

behavior of humans and other animals. Through this work, especially, they have discovered some of

the features that make an individual attractive to others.

Scientists are also learning that there may be a practical side to our obsession with beauty. A pretty

face may belong to a healthier person. Or it may simply be easier for our brains to process.

Looking at a set of photos, it’s easy to say which faces we find attractive. Different people will

usually agree on which faces those are. But few can say precisely why those faces seem so beautiful.

.

LESZEKGLASNER/ISTOCKPHOTO

This averageness refers to how similar a face looks to most other faces in a population. Average,

here, does not mean “so-so.” Rather, average faces are a mathematical average (or mean) of most

people’s features. And, in general, people find such faces quite attractive.[3]

Nature or nurture?

Are we born with a preference for certain kinds of faces? To find out, psychologist Judith Langlois

and her team at the University of Texas in Austin worked with young children and babies.

Some of their young recruits were just two to three months old. The researchers showed each baby

photos of two faces. One face was more attractive than the other. The scientists then recorded how

long the infants looked at each face.

Babies spent longer viewing the attractive faces than the unattractive ones. That meant they

preferred the pretty faces, says psychologist Stevie Schein. She works with Langlois. These findings

suggest that people prefer pretty faces very early in life. [3]

Research shows that people with more symmetrical faces don’t just look nice. They also tend to be

healthier than asymmetrical people. Genes provide the instructions for how a cell is to perform. All

people have the same number of genes. But people with more average faces tend to have a greater

diversity in the genes they are born with. And that, research has shown, can lead to a stronger

immune system and better health.

Research on birds also shows that female birds prefer good-looking guys. For example, among satin

bowerbirds, females prefer males whose feathers reflect more ultraviolet (UV) light. Researchers at

Auburn University in Alabama caught male bowerbirds and took blood samples. Males with blood

parasites had feathers reflecting less UV light than healthy males. So when females chose males with

UV-rich plumage, they weren’t just being shallow. They were using that information to find healthy

males to father their young.

Attractive faces, such as this one, tend to be symmetrical. They also

tend to have measurements similar to the population average.

Researchers have begun turning up some answers, though. Such as

symmetry. Faces that we deem attractive tend to be symmetrical,

they find. Attractive faces also are average.

In a symmetrical face, the left and right sides look like each other.

They’re not perfect mirror images. But our eyes read faces with

similar proportions on both sides as symmetrical.[3]

Adeline Loyau is a behavioral ecologist who has seen similar things in peacocks. She works at the

Helmholtz Center for Environmental Research in Leipzig, Germany. Eyespots are the vivid circles at

the ends of their tail feathers. She knew peahens prefer males with more eyespots. They also prefer

males that show off their tails more. Her work has now shown that healthier peacocks have more

eyespots in their tails. These birds also splay their flashy tails more frequently to the females.

Easy on the brain

Maybe we’re born with a preference for averageness because it tells us something about other

people. For example, it may help us find healthy mates.

Scientists discovered long ago that people show favor to those with a pretty face. Attractive people

are more likely to get jobs. They make more money than their less attractive coworkers. We even

tend to think attractive people are smarter and friendlier than less attractive people.

Studies also showed people with unattractive faces can even be labelled as less intelligent, less

sociable and less likely to help others. Medium attractive people got similar rankings to highly

attractive people for everything except sociability.[3]

In August 2019 the Brazilian Journal for Otorhinolaryngology published the results of a study on

assessment of facial analysis measurements by golden proportion.

The face is the most important factor affecting the physical appearance of a person. In facial

aesthetics, there is a specific mathematical proportion, which is called golden proportion, used to

measure and analyse facial aesthetic qualities in population.[2]

The GP is a commonly observed identity in nature. Clinical applications of the GP are mostly

employed in dental prostheses, aesthetic surgery, orthodontics and facial mask fields. The GP is used

to evaluate the aesthetic appearance of face in aesthetic surgery [2]

Although there is not a standard algorithm for beauty, it seems balance and harmony are important

characteristics of beauty. It reminds strongly of the golden ratio.

See video: https://www.youtube.com/watch?v=c8ccsE_IumM

Why is dentistry important?

Esthetic dentistry is the marriage between the ‘art and science of dentistry’. The simultaneous

application of technical and artistic skills enables a practitioner to achieve outstanding esthetic and

functional results. The importance of diagnosis and treatment planning prior to any procedure

cannot be over-emphasized, remembering that oral health and function are integral to successful

esthetic dentistry. To practise successful esthetic dentistry, the dental team must understand the

relevant principles, notably those of smile design, and be aware of the different inter-disciplinary

treatment modalities that are available.[4]

To achieve this goal involves many aspects of the dental profession, namely; orthodontics, maxilla-

facial and periodontal surgery, veneers, crowns and bridges, implants, tooth whitening, natural

looking restorations and oral hygiene.

When creating a beautiful smile, the dentists have to keep the following in mind:

1. The lips that frame the smile.

2. The gum tissue that perfectly outlines the smile creating the ideal background for the teeth

to stand out.

3. The color of the teeth that is uniform, bright, and clean.

4. The delicate incisal embrasures that help to give character and form to the teeth.

5. The dental arch that is broad and full, allowing for the perfect reflection of light.

6. The correct proportion of width and length among each tooth that together look balanced

and effortless. Our eyes are not distracted because it is a harmonious blend of nature’s

perfection.[5]

The following is a case study done by Dr Paresh Shah[6]

The use of a diagnostic wax-up has always been beneficial in the planning and execution of

restorative and surgical procedures. It serves multiple purposes from treatment planning,

communication with the interdisciplinary team and showing patients what possibilities exist for

treatment. Traditionally, impressions and a bite record are taken and sent to the lab. Information is

conveyed on a lab prescription to ask for a diagnostic wax-up based on the parameters requested to

achieve the patient’s goal for treatment. Nowadays, photos might be provided to the lab so they

have a better visualization of what the facial esthetics are like and how those results may be

optimized. This method still leads to an inherent challenge as the lab often doesn’t have accurate

details as to lip dynamics, facial expression and function. For that reason, accurate communication is

essential to minimize remakes or chair time if the diagnostic wax-up is significantly different than

expected.

What if we could convey more information in a simple, effective manner to allow the lab to better

understand what the patient’s condition is without someone having to meet the patient? As

technology continues to evolve we now have the advantage of digital workflows. Through

photography, video and impression scanners we can perform similar procedures using digital smile

design protocols. We have been exposed to many great interdisciplinary examples of digital smile

design cases that involve full mouth restorative. However, we can use these protocols to also

execute simple everyday dentistry as well.

The following is a clinical case of an everyday bonding procedure that many general practitioners

might perform on a regular basis. It was planned using a Digital Smile Design (DSD) protocol and all

lab procedures were digitally created.[6]

A 42-year-old female patient had has some large composites on her four anterior teeth that have

been breaking down and staining for some time (Fig. 1). She was interested in having new

composites placed with improved contours and balanced shading. She was hesitant whether to treat

the entire facial surfaces of her four anterior teeth or simply replace the fillings that had stains

around the margins. A procedure like this is typically performed by “free-handing” the shape using

direct composite bonding. However, creating symmetry and proportional restorations can

sometimes be challenging. The use of a stent or guide can facilitate a more predictable result.

Fig.1

The planning of this case was performed

using a Digital Smile Design (DSD)

protocol rather than conventional

methods. The protocol is simple and

involves a few specific photographs or

videos that can be taken on an iPhone or

digital SLR

Fig.2 Digital

scan of Mx arch with True Definition scanner

A short video of the patient talking as well as doing

some chewing and excursive movements provide the lab with valuable information that often is

hard to convey in writing.

Fig.4 Digital smile design creation using the DSD protocol.

The video, photos and digital impression were used by the lab (Aurum Group–Calgary, AB) to create

a 2D proposal or a “digital diagnostic wax-up” (Figs. 4 & 5). After approval of the digital rendition, a

3D model of the smile design was printed along with a PVS treatment stent (Fig. 6). The patient was

brought back for her treatment appointment and the diagnostic stent was used to provide an intra-

These are combined with a digital

impression (True Definition scanner – 3M

Dental) to create a smile design proposal

and treatment guide

By using high resolution video on an

iPhone, it’s possible to extract individual

photographs for the smile design. Six

simple views were used to create a digital

diagnostic wax-up from the lab (Fig. 3).

The other advantage of video is that you

can provide the lab with some dynamic

parameters for them to evaluate a

patient’s smile and speech.

.

The video, photos and digital impression were

used by the lab (Aurum Group–Calgary, AB) to

create a 2D proposal or a “digital diagnostic

wax-up” (Figs. 4 & 5). After approval of the

digital rendition, a 3D model of the smile design

was printed along with a PVS treatment stent

(Fig. 6).

oral “mock-up” to show the patient what the contours of the new restorations might look like. The

mockup was created using an A1 shaded bis-acyl resin (Tempsmart – GC America) that was not

bonded into place, but stayed secure long enough to allow the patient a chance to evaluate her

smile (Figs. 7 & 8). A wall mirror was used to give the patient an idea of what the new smile would

look like from “conversation

distance.”

Fig.5 Virtual rendition of the 2D smile design prior to 3D processing. Fig. 6 Printed model based on the 2D to 3D DSD protocol.

Fig. 7 Bis-acryl resin being placed inside stent for intra-oral “mock-up”.

Fig. 8 Full face view of Intra-oral “mock-up” based on the DSD protocol.

.

Fig 9 3D mock-up used as a prep guide.

Fig. 10 Isolation of individual tooth to perform bonding protocol

Each tooth was restored sequentially in a similar manner and then finished and polished at the same

time (Renamel – Cosmedent-Clinical Research Dental )Should the patient decide to treat more teeth

at a future date, the same design may be used if significant changes have not been made (Figs. 12 &

13).

The mock-up was kept in place and

used as a preparation guide to provide

even reduction based on the desired

outcome. The remaining fragments

were removed prior to restoring. Each

tooth was restored separately before

moving on to the next

Mylar matrices were placed between

individual preparations prior to

bonding

To simplify placement of the

composite a clear matrix material

based on the 3D design was used

Memosil – Heraeus Kulzer. The clear

matrix allowed the composite to be

placed with sufficient adaptation to

prevent voids and cure through

Fig. 12 Retracted view of final restorations. Fig. 13 Full face smile of final restorations.

Although there are some offices that have cad/cam technology and software to create their own

digital smile design proposals, the majority doesn’t have the full technology. For those that continue

to use their lab, the process is simple and can allow accurate and predictable results in less time. The

communication is fast as it can be done via a secure email portal. The use of a digital protocol can

simplify the procedure and communication with the lab. As one gets comfortable with simple

restorative cases the DSD protocol may be used for more advanced cases. The digital impression and

photos can be superimposed with a conebeam image to help plan implant cases. This also allows for

facial esthetics to be addressed. The records may then be shared with the appropriate specialists to

make treatment planning more effective. Most people know how to use a handheld phone and as

more continue to adopt digital scanners, the need for time-consuming impressions, plaster and wax

will become far less necessary. These digital workflows are predictable and easy to implement with

the help of an experienced lab. [6]

Tooth Whitening

Tooth whitening falls under the scope of dentists and oral hygienists. Only oral hygienists that

qualified after 2013 and hygienists that did the expanded functions course are allowed to legally

whiten teeth.

In January 2018 Dimensions of Dental Hygiene published this article by So Ran Kwon ( DDS, MS, PhD,

MS) on the innovation in tooth whitening[7]

The demand for whiter teeth has spurred the development of many innovations in professional oral

health care technologies, as well as in over-the-counter (OTC) products.

Discoloration can present in various ways, and, depending on the nature of the discoloration, the

treatment approach and outcome can vary significantly. When discussing tooth whitening, it is

important to acknowledge the work of many pioneers who enabled the profession to offer tooth

whitening as a conservative, alternative treatment to whiten and lighten discolored teeth that

otherwise would have to be treated with veneers or crowns—with concomitant (simultaneous)

removal of sound tooth structure.

Historically, professional whitening procedures were performed in the dental office, typically using

concentrated hydrogen peroxide (H2O2) and by isolating surrounding soft tissue to avoid contact

with the whitening agent. Although this proved effective, drawbacks included lengthy chairtime,

cost, and the risk of dentinal hypersensitivity. These downsides were addressed by Haywood and

Heymann in 1989, with the introduction of nightguard vital bleaching using 10% carbamide peroxide

in a custom tray worn at night.

This technique offered the possibility of whiter vital teeth at a reduced cost, and with fewer side

effects. It also marked an evolutionary step in tooth whitening, as the patient took on the

responsibility of performing the procedure at home.

Advances in whitening materials and delivery methods appeared as the oral health care industry

realized it could address consumers directly by introducing OTC (over the counter) whitening

products. Among these offerings, technology was introduced in 2000 that used hydrogen peroxide

on a clear strip of tape that was applied to the teeth. Then, as now, a drawback of OTC tooth

whitening products used without professional supervision is the potential lack of a proper diagnosis

for the cause of tooth discoloration, which would allow clinicians to suggest appropriate therapy,

and monitor the efficacy and safety of treatment.

In response to consumers’ desires for improved perception of tooth color, dental manufacturers

often promote the whitening component in dentifrices (toothpastes). While ordinary whitening

toothpastes relied mainly on their efficacy in removing extrinsic tooth stains, the newer generation

or “advanced whitening” dentifrices also claim to be effective in removing intrinsic stains.

The diversity of whitening methods has created confusion among patients in terms of expectations

that can be realized with each treatment modality. The purpose of this article is to define extrinsic

and intrinsic discoloration, help clinicians understand the active ingredients and chemistry behind

each whitening technique, and strategies for addressing hypersensitivity. This will facilitate

appropriate decision-making, based on the nature of tooth discoloration.

TOOTH COLOR AND TYPES OF DISCOLORATION

Tooth color is primarily determined by the reflectance of the dentin, modified by the absorption,

scattering, and thickness of the enamel. Tooth color varies among individuals, among teeth in the

same individual, and even within the same tooth. Furthermore, tooth color is not constant over a

lifetime, and can change for various reasons.

The etiology (cause) of tooth discoloration is broadly classified as extrinsic (from outside) or intrinsic

(from within), depending on the origin of the stain. It has also been reported that long-standing

extrinsic stains can become internalized, making removal more challenging (a good example is

permanent discoloration of a longstanding smoker). Extrinsic stains of various color—such as those

caused by coffee, tea, red wine, tobacco, and colored food—are caused by superficial accumulation

of residue on the enamel surface. These can be accentuated by pitting or irregularities of the

enamel, salivary composition, salivary flow rates, and poor oral hygiene. Stains remain on the tooth

surface due to attractive forces, including long-range interactions (such as electrostatic and van der

Waals forces [weak chemical bonds]), and short-range interactions (such as hydration forces,

hydrophobic interactions, dipole-dipole forces[medium chemical bonds], and hydrogen bonds[strong

chemical bonds]).

Intrinsic discolorations are incorporated during tooth formation or after eruption, and are

attributable to the presence of stain molecules within the enamel and dentin. Pre-eruptive stains

arise due to dental fluorosis, tetracycline staining, hematologic disorders, and inherited

developmental defects of enamel or dentin without systemic features.

Post-eruptive intrinsic stains can result in local discoloration. The severity varies according to the

etiology, and may range from mild yellow/orange to dark brown and black. These are commonly

associated with caries, restorative materials, and pulpal hemorrhage.

Despite the fact that enamel is inert (solid) and does not have any remodeling capacity, it still

undergoes continuous, dynamic ion exchange with the oral biofilm—with calcium phosphate apatite

crystals moving in both directions to maintain proper mineral balance.10 In fact, enamel and dentin

act as a semipermeable membrane that allows small molecules to pass into the tooth structure. This

may account for reports of tooth discoloration from extrinsic sources becoming internalized. The key

properties that cause enamel and dentin to bind to and retain staining molecules internally,

however, are still not well understood.

TOOTH WHITENING CHEMISTRIES

Traditionally, stains of extrinsic origin were removed by toothbrushing or dental prophylaxis, which

relies on abrasive action. Stains of intrinsic origin, by comparison, could be removed only by oral

health professionals using oxidizing agents, such as hydrogen or carbamide peroxide. There has been

a paradigm shift, however, with two major events taking place. The first is the incorporation of

oxidizing agents into OTC whitening products, as well as dentifrices. The second development is

emerging evidence that extrinsic stains can become internalized, which makes a strict distinction

between extrinsic and intrinsic discoloration more difficult to establish. One might argue, therefore,

whether every type of discoloration eventually can be treated with self-applied methods on a daily

basis.

WHITENING DENTIFRICES

Whitening dentifrices basically contain the same functional ingredients of ordinary toothpaste

formulations. These include:

Solid cleansing abrasive materials that aid in physically removing the stains with the use of

hydrated silica, calcium carbonate, dicalcium phosphate dihydrate, calcium pyrophosphate,

alumina, perlite, and sodium bicarbonate

Humectants (moisturising agent that does not compromise the properties of the product)

Thickening agents

Surfactants (Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents,

and dispersants.)

Active agents, such as fluoride, to impart anticariogenic health benefits

Flavoring

Sweeteners

Opacifying agents (Substances added to transparent or clear cosmetic products to make

them more light and near-radiation impenetrable.)[8]

Coloring agents

Buffering and preserving agents to maintain stability

In addition to these basic ingredients, whitening dentifrices may contain peroxide, enzymes, citrate,

pyrophosphates, and hexametaphosphates to augment (improve) the cleaning and/or prevention of

stains. Although incorporating additional chemicals seems easily accomplished, it is not a simple

process because potential interactions with new chemicals may adversely affect pre-existing

characteristics, such as stability, efficacy, and consistency.

Extensive research has been conducted in optimizing the stain removal potential of dentifrice

abrasives, while minimizing any deleterious wear effects to the tooth surface. The relative safety of

abrasives is established by standard methods referred to as relative dentin abrasivity. A study

comparing dentifrices showed that, with few exceptions, dentifrices marketed as whitening products

were generally more abrasive to dentin, especially those containing silicas. The stain-removal

potential of dentifrices in clinical trials are usually evaluated with common indexes, including the

Lobene Stain Index or Macpherson-modified Lobene Stain Index, which are related to the area and

intensity of the stain.

Another attribute of dentifrice is its polishing ability that can increase luster and improve esthetics,

while also rendering the tooth surface less susceptible to further staining. Because toothbrushing is

performed on a daily basis, further advances in technology would likely benefit public health. With

continuous innovations, dentifrices may enable effective stain prevention and also include

components that can penetrate deep into the enamel and dentin to interact with intrinsic stains.

DO-IT-YOURSELF (DIY) WHITENING

Do-it-yourself (DIY) whitening is promoted on myriad news outlets that provide information about

at-home whitening remedies, including rubbing crushed strawberries, apples, or activated charcoal

on teeth. The advocated use of these fruits is based on anecdotal perception, with the rationale

being that they contain malic acid. The argument for using charcoal is based on its abrasiveness in

removing stains.

The use of DIY whitening with strawberries has been investigated in vitro and compared with

conventional whitening modalities, including the use of an OTC product, professionally dispensed,

patient-applied home whitening, and professionally applied in-office whitening. At three months

post-whitening, the DIY group showed an overall tooth color change similar to the negative control,

with values of less than the 50:50 perceptibility threshold of the human eye. The greatest overall

color change was observed for the professionally applied in-office whitening group, with no

significant differences noted between the OTC and patient-applied home whitening groups.

Another in vitro study evaluated the effect of various tooth whitening modalities on microhardness,

surface roughness, and surface morphology of the enamel. While this study found that DIY

whitening with strawberries did not affect surface roughness or surface morphology, it noted a

significant reduction in microhardness.

DENTIST-DISPENSED, PATIENT-APPLIED HOME WHITENING

Dentist-dispensed, patient-applied home whitening is a well-established whitening procedure. It

allows proper diagnosis, treatment planning, and professional supervision. It is relatively easy to

perform, and may be less expensive than in-office whitening. Initially, it was used with 10%

carbamide peroxide during nighttime bleaching sessions. A study of the kinetics of carbamide

peroxide showed that it remains active for up to 10 hours, with about half of the active agent used

up in the first 2 hours. Concentrations indicated for at-home whitening range between 10% to 35%.

A 10% carbamide peroxide solution breaks down into 3.35% hydrogen peroxide and 6.65% urea.

Urea further breaks down into ammonia and water, and may provide beneficial side effects—

including slowing the caries process by increasing the pH value of the solution.

Carbamide peroxide products usually contain either a carbopol or glycerine base. The carbopol base

slows the release of hydrogen peroxide, making it more effective over a longer period. More

recently, however, H2O2 products have been introduced for individuals who cannot tolerate wearing

trays at night. The H2O2 concentration generally ranges from 7.5% to 9.5%, and the active time

ranges from 30 minutes to 60 minutes; in addition, it can be applied during daytime.

IN-OFFICE WHITENING

In-office whitening is the initial form of tooth whitening, and is performed with H2O2-based materials

at concentrations of up to 40%. It is an alternative for patients who cannot tolerate trays, or who

desire an instant whitening outcome and prefer to have the procedure performed in the office.

A study that evaluated the time required to achieve a six-tab difference on a Vita Classical shade

guide found that in-office whitening produced the fastest results, followed by professionally

supervised at-home whitening. The researchers noted that OTC whitening required the most time.

That said, the use of high-concentration H2O2 materials associated with in-office whitening also

resulted in generally higher incidence of dentinal hypersensitivity. Recently, manufacturers have

attempted to address this issue by reducing concentration levels and changing the delivery method

from gels to varnish systems.

DENTINAL HYPERSENSITIVITY

Whitening procedures, whether over-the-counter or professional, can cause dentinal

hypersensitivity and demineralization. Carbamide peroxide and H2O2 are able to penetrate through

enamel and dentin. The majority of studies show that H2O2– and carbamide peroxide-containing

products had no clinically significant adverse effects on enamel. However, two clinical cases did

show significant enamel damage associated with the use of OTC whitening products. Eventually,

upcoming in situ and in vivo studies will provide more evidence on this topic.

In order to address the possible concerns of demineralization associated with whitening, several

remineralization strategies using fluoride and calcium phosphate technologies have been suggested.

Remineralization is the process whereby calcium and phosphate ions are supplied from a source

externally to the tooth to promote ion deposition into the crystal voids in demineralized enamel to

produce mineral gain. Calcium and phosphate ions are available in human saliva but the net

remineralization may be too small and slow.

Agents to promote remineralization, as well as reduce tooth sensitivity after whitening include

fluoride, potassium nitrate, amorphous calcium phosphate (ACP), casein phosphopeptide-ACP,

calcium sodium phosphosilicate, arginine calcium carbonate, and tri-calcium phosphate. Whether

these active components truly assist in remineralization after whitening has yet to be determined.

However, the application of topical fluoride post-whitening has been demonstrated to be effective

in restoring the mineral content and microhardness values back to the baseline level.

CONCLUSION

Tooth whitening is a dynamic process initiated by the movement of the active ingredient through

the tooth structure, where it interacts with stain molecules and induces micromorphologic

alterations on the tooth surface—and within the tooth—to affect the dentition’s optical properties.

The development of, and continuous advances in, whitening materials and techniques reflect the

efforts of the dental profession and industry toward preserving tooth structure and enhancing

esthetics.

Clinicians and patients who initiate professional whitening treatment, as well as consumers who

elect OTC therapy, will benefit from future innovations in whitening technology that are based on an

improved understanding of the chemistry behind the tooth whitening process.[7]

NEW APPROACH TO BLEACHING [9]

There is new approach to bleaching (whitening) that utilizes a unique and proprietary ionic

technology—without the presence of light or heat—to accelerate the breakdown of hydrogen

peroxide. Clinicians should note that applying a gingival barrier is also necessary in this procedure to

protect the soft tissues. With this method, a specifically formulated hydrogen peroxide gel is

delivered into a proprietary tray that contains a battery in a sealed system. The gel is used on the

facial surface, along with a secondary conducting gel covering the incisal and lingual surfaces. When

the system is initiated, electrochemical action activates the ionization process. The resulting

ionization aids in the breakdown of the hydrogen peroxide and also raises the mixture’s pH. The

manufacturer recommends three 10-minute application cycles. The gel and teeth remain hydrated

throughout the procedure, and patients do not experience any sensation of the electrochemical

process. This method is also safe to use on individuals with cardiac pacemakers.

The trays are designed to administer the bleaching agent to the upper and lower arches at the same

time. Patients with heavy and intrinsic staining can benefit from a combination treatment approach,

and the same tray can be used for the at-home-bleaching step using a proprietary 9% hydrogen

peroxide agent.

Because custom trays are not needed, this new system saves chairtime, as well as costs associated

with making impressions, and fabricating models and custom trays. It is also comfortable for patients

as they can remain occluded during the procedure.

Conducting gel is applied on the lingual

and occlusal surfaces, both on the upper

and lower arches.

Both gels must be in contact to ensure

the ionization process.

A proprietary hydrogen peroxide

mixture is applied on the facial side

of the special, battery-powered tray,

both on the upper and lower arches

After the tray is seated and the patient

occludes, activate the tray’s button.

The green light remains on for 10

minutes. After the first cycle, the tray

is removed, as is any remaining gel on

the teeth or tray. Next, a new set of

hydrogen peroxide and conducting

gels is placed, e procedure is repeated

for three cycles

Question time.

To get your CPD points, you have to get 70% or more. You have 3 chances to do the test should you

not get it first time around.

1. Choose the correct statement:

a. Scientists found there is a link between beauty and health in humans and animals.

b. Studies show babies are more interested in attractive people.

c. All of the above.

2. Choose the incorrect statement:

a. Attractive people are perceived to be smarter and friendlier that unattractive people.

b. Attractive are more likely to be employed.

c. None of the above.

3. According to the Golden ration, the length of a beautiful face should be approximately ___%

more than the width of the face.

a. 36

b. 50

c.-15

4. Oral hygiene is one aspect of esthetic dentistry.

a. True

b. False

5. Choose the incorrect answer:

When creating a beautiful smile, the dentists have to keep the following in mind:

a. The delicate incisal embrasures that help to give character and form to the teeth.

b. The color of the patient’s eyes.

c. The patient’s budget

d. All of the above

6. A diagnostic wax-up is beneficial to:

a. the dentists

b. the patient

c. the dental technician

d. all of the above

7. When using digital smile design, a “mock up” will give the patient and the dentist the opportunity

to see what the final result will look like.

a. True

b. False

8. Complete:

It is illegal for ________________ to do tooth whitening.

a. Dentists

b. Dental assistants

c. Oral hygienists

9. The color of the tooth is determined by

a. the reflectance of the dentin

b. the thickness of the enamel

c. all of the above

10. Extrinsic stains are

a. caused by coffee, tea, red wine, tobacco, and colored food

b. incorporated during tooth formation or after eruption, and are attributable to the presence of

stain molecules within the enamel and dentin

c. permanent stains caused by long-term use of staining agents.

11. . Intrinsic stains are

a. caused by coffee, tea, red wine, tobacco, and colored food

b. incorporated during tooth formation or after eruption, and are attributable to the presence of

stain molecules within the enamel and dentin

c. permanent stains caused by long-term use of staining agents.

12. A study comparing dentifrices with silica showed that, with few exceptions, dentifrices marketed

as whitening products were generally

a. more prone to cause gum infection.

b. more abrasive to dentin.

c. more prone to cause gum recession.

13. In vitro studies showed that DIY tooth whitening techniques e.g. the use of strawberries

a. compromised the hardness of the enamel

b. caused roughness of the surface

c. caused unnatural wear on the enamel

14. Choose the correct answer: Carbamide peroxide products

a. release hydrogen peroxide slower, making it more effective over a longer period.

b. can be used overnight

c. breaks down in hydrogen peroxide and urea

d. all of the above

15. Agents to promote remineralization, as well as reduce tooth sensitivity after whitening are not

recommended.

a. true

b. false

References.

1. https://www.theodysseyonline.com/the-definition-true-beauty

2. https://www.sciencedirect.com/science/article/pii/S1808869418303161

3. https://www.sciencenewsforstudents.org/article/what-makes-pretty-face

4. https://www.sciencedirect.com/topics/medicine-and-dentistry/esthetic-dentistry

5. https://clinicalmastery.com/tooth-width-proportion-formula/

6. https://www.oralhealthgroup.com/features/the-use-of-digital-smile-design-for-everyday-dentistry/

7. https://dimensionsofdentalhygiene.com/article/innovation-in-tooth-whitening

8. https://www.quimivita.es/index.php?directurl=cosmetica/opacificantes/&lang=en

All links were last accessed 29/02/2020