Dental Crowns

Dental Crowns in Kitchener

A dental crown can restore a tooth that has been weakened by decay, a large filling, fracture, wear or previous dental treatment. It covers the visible portion of the tooth, helping restore its shape, function and appearance while protecting the remaining tooth structure.

At MI Dental in Kitchener, crowns are not selected from a one-size-fits-all menu. The material, design and preparation are chosen according to:

• How much healthy tooth remains
• Whether the tooth is in the front or back of the mouth
• The forces placed on it during chewing
• Grinding or clenching habits
• The appearance of the surrounding teeth
• The condition of the gums and supporting bone
• Whether the crown will be bonded or conventionally cemented
• Your priorities and preferences

Our objective is not simply to place a crown. It is to determine whether a crown is the most appropriate restoration and, when it is, design one that functions naturally within your bite.

What Is a Dental Crown?

A dental crown is a custom-made restoration that covers most or all of the visible portion of a prepared tooth.

It may help a damaged tooth:

• Withstand chewing forces
• Regain its normal shape and contour
• Maintain contact with neighbouring teeth
• Protect weakened cusps
• Support a large restoration
• Improve colour or appearance
• Function more predictably after extensive treatment

Patients often describe a crown as a “cap.” That is a useful visual description, although a properly made crown is more than a shell placed over a tooth. Its internal fit, margins, contacts, bite, material thickness and relationship with the gum tissue all influence how it performs.

When Might a Dental Crown Be Recommended?

A crown may be considered when a tooth has lost enough structure that a direct filling may no longer provide predictable reinforcement.

Common reasons include:

A Large Cavity or Failing Filling

When decay or an existing filling occupies a substantial portion of the tooth, the remaining walls and cusps may become vulnerable to fracture.

Replacing one increasingly large filling with another is not always the most durable approach. A crown can surround and protect the remaining structure when full coverage is appropriate.

A Cracked or Fractured Tooth

A crack may cause discomfort when chewing or when pressure is released from the tooth.

The treatment depends on:

• The location and depth of the crack
• Whether the crack extends beneath the gumline
• The condition of the pulp or nerve
• How much tooth structure remains
• Whether the tooth can be restored predictably

A crown may stabilize a restorable cracked tooth by holding its cusps together. However, a crown cannot heal a crack or guarantee that it will never progress.

A Tooth After Root Canal Treatment

Root canal treatment removes infected or inflamed tissue from inside the tooth, but it does not replace tooth structure previously lost through decay, fracture or access preparation.

Back teeth that have undergone root canal treatment frequently require protection of their cusps. The exact restoration may be a crown or, in selected cases, another form of cuspal-coverage restoration such as an onlay. Remaining tooth structure is one of the most important considerations. Research supports the importance of cuspal protection for many root-treated posterior teeth while also showing that conservative onlays may be appropriate in selected cases.

Severe Tooth Wear

Teeth may become shortened or weakened by:

• Grinding or clenching
• Acid erosion
• An uneven bite
• Long-term loss of posterior support
• Developmental conditions

Crowns may form part of a broader restorative plan when significant tooth structure and function have been lost. These cases require careful evaluation of the entire bite rather than treating one tooth in isolation.

A Misshapen or Heavily Discoloured Tooth

A crown may improve the shape or appearance of a tooth when the tooth also requires substantial structural restoration.

When the concern is primarily cosmetic and the tooth is otherwise strong, a veneer, bonding or whitening may be a more conservative alternative. We consider these options before recommending full coverage.

Support for a Dental Bridge

Crowns may be used as retainers for a conventional dental bridge. Material selection becomes especially important because a bridge experiences different stresses from a single crown.

Restoration of a Dental Implant

An implant crown replaces the visible tooth portion over a dental implant. Although it is also called a crown, its support and connection differ from those of a crown placed over a natural tooth.

Does Every Large Filling Need a Crown?

No.

A crown is one option within a range of restorative treatments. Depending on the tooth, alternatives may include:

• A direct bonded filling
• An inlay
• An onlay or partial-coverage restoration
• Dental bonding
• A veneer
• Monitoring when treatment is not yet required

We consider how much healthy enamel and dentin remain, whether the cusps are undermined, the location of cracks, the patient’s bite and the history of the tooth.

Preserving healthy tooth structure is important. A crown should be recommended because the tooth is likely to benefit from full coverage—not merely because a large filling happens to be present.

How We Evaluate a Tooth Before Recommending a Crown

The success of a crown begins before the tooth is prepared.

Clinical Examination

We assess:

• Existing decay and restorations
• Cracks and fracture lines
• Remaining tooth structure
• Gum health
• Tooth mobility
• Sensitivity and symptoms
• The contact with adjacent teeth
• How the tooth meets the opposing arch
• Signs of grinding or clenching

Dental X-Rays

Appropriate dental X-rays may help evaluate:

• Decay beneath an existing restoration
• The roots and surrounding bone
• Previous root canal treatment
• Infections around the root
• The depth of decay
• The relationship of the tooth to the supporting structures

An X-ray cannot show every crack, so radiographic findings are interpreted together with the clinical examination and symptoms.

Restorability

Before proceeding, we must determine whether enough sound tooth structure remains to support a predictable restoration.

A tooth may require additional treatment before a crown, such as:

• Removal of decay
• A core buildup
• Root canal treatment
• Periodontal treatment
• Crown-lengthening surgery
• Orthodontic movement in selected cases

In other situations, the damage may extend too far below the gum or root for the tooth to be restored predictably. In that case, extraction and replacement options may need to be discussed.

Choosing the Right Crown Material

Patients commonly ask, “Which crown is best?”

There is no universally best crown. The more useful question is:

Which material offers the best balance of strength, appearance, preservation and predictability for this particular tooth?

Modern crown materials have different optical and mechanical properties. Research indicates that appropriately selected zirconia, lithium-disilicate and metal-ceramic single crowns can all perform well.

Crown Material Comparison

The ADA recognizes all-ceramic, metal-ceramic and noble-metal alloys as established categories for indirect restorations, each with different clinical uses and limitations.

Zirconia Crowns

Zirconia is a high-strength dental ceramic made from zirconium dioxide.

Its crystalline structure helps resist the propagation of cracks through a process known as transformation toughening. This property contributes to zirconia’s high fracture toughness and has made it especially useful where substantial chewing forces are expected.

Zirconia crowns may be:

• Monolithic, meaning the restoration is milled primarily from one zirconia structure
• Layered, meaning porcelain is applied over zirconia to enhance appearance
• Multilayered or high-translucency, using newer formulations intended to improve natural colour gradation

Zirconia may be considered for:

• Molars and premolars
• Patients with strong bite forces
• Patients who grind or clench
• Teeth with limited restorative space
• Selected bridges
• Patients who prefer a restoration without a metallic alloy framework

Important considerations

Not all zirconia is the same.

Increasing translucency can affect strength, and a highly aesthetic zirconia may not have identical properties to an opaque, high-strength formulation. Layered zirconia can achieve excellent aesthetics, but the outer porcelain layer introduces a potential for chipping.

The surface should also be properly finished and polished after bite adjustment.

Lithium-Disilicate and E.max Crowns

E.max is a widely recognized family of lithium-disilicate glass-ceramic restorations.

Lithium disilicate combines a glassy matrix with reinforcing crystals. This gives it a favourable balance of strength and translucency, allowing it to transmit and reflect light in a way that can closely resemble natural enamel.

IPS e.max CAD is officially indicated by its manufacturer for single crowns in both anterior and posterior regions when its clinical requirements are met.

Lithium disilicate may be considered for:

• Front teeth
• Premolars
• Selected molars
• Teeth where shade and translucency are especially important
• Teeth that can benefit from adhesive bonding
• Cosmetic restorative cases involving veneers, inlays or onlays as well as crowns

Important considerations

Lithium disilicate is strong, but zirconia generally offers greater fracture toughness under very heavy loads.

Material choice therefore depends not simply on whether the tooth is anterior or posterior, but also on:

• Available material thickness
• Remaining enamel
• Preparation design
• Bite forces
• Parafunction
• How the crown will be bonded
• The appearance of neighbouring teeth

What Does “Porcelain Crown” Mean?

Patients often use porcelain crown as a general term for any tooth-coloured crown.

Modern dentistry distinguishes among several ceramic materials:

• Traditional feldspathic porcelain
• Leucite-reinforced ceramics
• Lithium disilicate
• Zirconia
• Porcelain layered over metal or zirconia

This distinction matters because these materials do not have identical strength, translucency or bonding requirements.

When we discuss a “porcelain” crown with you, we explain the actual material being considered rather than relying only on a broad marketing label.

Porcelain-Fused-to-Metal Crowns

A porcelain-fused-to-metal crown, or PFM crown, contains:

• An internal metal-alloy framework
• An external layer of tooth-coloured porcelain

PFM crowns have a long clinical history. The metal framework provides rigidity, while the porcelain improves appearance.

PFM crowns may be considered for:

• Selected single crowns
• Multi-unit bridges
• Situations requiring a rigid framework
• Cases where a time-tested metal-ceramic restoration is preferred

Limitations

Because the underlying metal is opaque, a PFM crown may not transmit light as naturally as an all-ceramic restoration.

Other considerations include:

• A grey or dark margin becoming visible if the gums recede
• Chipping of the outer porcelain
• Less natural translucency in highly visible front teeth
• The composition of the metal alloy

PFM crowns remain a valid treatment option, but newer ceramics have reduced how frequently they are selected for highly aesthetic areas.

Our detailed article about porcelain-fused-to-metal crowns provides a deeper explanation of their structure and history.

Gold Crowns

Gold crowns are made from dental alloys containing gold and other metals selected to improve strength and handling.

They have historically performed well in posterior teeth because they can be:

• Durable
• Relatively thin
• Precisely adapted
• Polished smoothly
• Gentle to opposing enamel when properly finished

Clinical research continues to show strong survival for indirect gold restorations, although every restoration remains dependent on tooth condition, design, hygiene and bite.

The principal limitation is appearance. For that reason, gold is usually considered for back teeth that are not prominent when smiling.

The cost of high-noble alloys can also fluctuate with metal prices.

How We Select a Crown Material

Material selection is based on more than choosing the strongest or whitest option.

Location of the Tooth

A front tooth places greater emphasis on translucency, shade and surface texture.

A back molar may place greater emphasis on fracture resistance and available restorative thickness.

Remaining Tooth Structure

A crown must be supported by an appropriate preparation.

The amount and quality of remaining tooth structure can influence:

• Retention
• Resistance to dislodgement
• Material thickness
• The possibility of adhesive bonding
• The long-term outlook for the tooth

Bite and Parafunction

Grinding and clenching increase the forces placed on crowns and natural teeth.

A stronger material may be considered, but strength alone does not solve the underlying problem. The bite must be evaluated, and a protective night guard may be recommended.

Available Space

Every material requires enough thickness to function predictably.

When space is limited, the dentist must consider whether sufficient reduction can be achieved without unnecessarily weakening the tooth.

Aesthetic Requirements

Matching one front tooth can be more demanding than restoring several teeth together.

We assess:

• Shade
• Brightness
• Translucency
• Surface texture
• Shape
• Symmetry
• The colour of the underlying tooth
• The appearance of neighbouring restorations

Gum Position

The margin of the crown must relate appropriately to the gum tissue.

Whenever possible, margins that are accessible for cleaning and evaluation are desirable. Deep margins may be necessary in some cases but can make isolation, impressions, cement removal and long-term hygiene more difficult.

Opposing Teeth and Restorations

We also consider what the crown will contact:

• Natural enamel
• Another ceramic crown
• A denture tooth
• An implant restoration
• A heavily worn opposing tooth

The Dental Crown Procedure at MI Dental

Most laboratory-made crowns are completed over two main appointments.

Additional visits may be necessary when the tooth requires preliminary treatment or when the case involves complex aesthetic planning.

First Appointment: Examination and Preparation

1. Local Anaesthetic

The tooth and surrounding area are numbed to keep the preparation comfortable.

2. Removing Decay and Existing Restorative Material

We remove decay, unsupported tooth structure and portions of an old restoration that should not remain beneath the new crown.

3. Core Buildup When Required

If a substantial amount of tooth structure is missing, a core material may be used to rebuild the internal foundation of the preparation.

4. Shaping the Tooth

The tooth is carefully shaped to create room for the crown and provide an appropriate path for placement.

The amount and form of preparation depend on the selected material and the condition of the tooth.

5. Digital Scanning

Instead of relying exclusively on traditional impression material, we can capture a detailed digital scan of the prepared tooth, adjacent teeth and opposing bite.

The scan records:

• The preparation
• Crown margins
• Neighbouring contacts
• Opposing teeth
• Bite relationship

Digital technology improves communication with the dental laboratory, but the accuracy of the final restoration still depends on tissue management, preparation design, scanning, laboratory fabrication and clinical evaluation.

6. Shade and Aesthetic Records

For visible teeth, we may record:

• Tooth shade
• Photographs
• Surface characteristics
• Translucency
• The colour of the underlying tooth
• Special instructions for the ceramist

Complex front-tooth cases may benefit from additional laboratory communication or a custom shade appointment.

The Temporary Crown

A temporary crown is placed while the laboratory fabricates the final restoration.

It serves several important functions:

• Protects the prepared tooth
• Reduces sensitivity
• Maintains tooth position
• Preserves contact with adjacent teeth
• Helps prevent opposing teeth from moving
• Supports the gum contour
• Allows basic chewing and appearance during the laboratory phase

A temporary crown is made from provisional material and temporary cement, so it is not as strong or retentive as the final crown.

While wearing your temporary crown:

• Avoid chewing hard or sticky foods directly on it
• Floss carefully
• Slide the floss out through the side rather than lifting forcefully upward
• Contact us if the temporary becomes loose or breaks
• Do not leave the tooth uncovered until the final visit

The ADA similarly advises avoiding chewing gum and sticky foods while a temporary crown is in place.

Laboratory Fabrication

The digital records and prescription are sent to a dental laboratory.

Depending on the material, the crown may be:

• Milled using CAD/CAM technology
• Pressed from ceramic
• Cast from a metal alloy
• Layered and characterized by a dental ceramist
• Stained and glazed
• Polished and inspected

Technology provides precision, but laboratory artistry remains especially important when matching visible teeth.

Second Appointment: Final Crown Placement

At the final visit, the temporary crown is removed and the prepared tooth is cleaned.

Before permanent placement, we evaluate:

Marginal Fit

The edge of the crown should adapt appropriately to the prepared tooth.

Contacts

The crown must contact neighbouring teeth firmly enough to reduce food trapping without making flossing impossible.

Bite

We check the crown during normal closure and jaw movements.

A crown that feels comfortable while sitting upright may feel different during chewing, so tell us if the tooth feels “high” afterward.

Shape and Appearance

For visible crowns, we assess:

• Shade
• Length
• Width
• Contour
• Symmetry
• Relationship with the gums
• Overall appearance in the smile

Cementation or Bonding

The crown is secured using a cement or adhesive protocol selected for the material and clinical situation.

Excess cement is removed, the contacts are checked again and the bite is verified.

How Long Does a Dental Crown Last?

There is no guaranteed lifespan for a crown.

Many crowns function successfully for a decade or longer, but longevity varies considerably according to:

• The amount of remaining tooth structure
• Crown design and material
• Fit and cementation
• Bite forces
• Grinding or clenching
• Oral hygiene
• Cavity risk
• Gum health
• Diet and dry mouth
• Smoking
• Trauma
• Attendance for preventive care

Systematic reviews generally report high five-year survival for modern metal-ceramic, lithium-disilicate and zirconia single crowns, but survival statistics describe groups of restorations—not a guaranteed expiry date for one patient’s crown.

Why Might a Crown Eventually Need Replacement?

A crown may need repair or replacement because of:

• Decay at the crown margin
• Fracture of the underlying tooth
• Chipping or fracture of the crown
• Loss of cement or bonding
• Gum recession exposing the margin
• Significant wear
• A change in the bite
• Root canal complications
• Aesthetic changes
• Trauma
• Failure of the supporting tooth

The crown itself cannot develop a cavity, but the natural tooth at or beneath its margin can.

Caring for a Dental Crown

A crowned tooth should be cleaned much like a natural tooth.

Brush Thoroughly

Brush twice daily with fluoride toothpaste, paying particular attention to the gumline around the crown.

Clean Between the Teeth

Use floss, an interdental brush, a floss threader or another device appropriate for the contacts and restoration.

Our guide to types of dental floss can help explain the available options.

Avoid Using Teeth as Tools

Do not use crowned or natural teeth to:

• Open packaging
• Crack nuts
• Chew ice
• Hold hard objects
• Bite fishing line or thread

Manage Grinding and Clenching

A night guard may be recommended when grinding or clenching threatens the crown or surrounding teeth.

A guard reduces risk; it does not make a restoration indestructible.

Attend Preventive Visits

During examinations, we monitor:

• Crown margins
• Gum health
• Bite
• Mobility
• Chipping
• Decay
• Changes visible on appropriate X-rays

Possible Risks and Limitations of Dental Crowns

Crowns are commonly performed, but no dental restoration is without risk.

Possible concerns include:

• Temporary sensitivity
• Persistent sensitivity
• Need for root canal treatment
• Gum irritation
• Difficulty cleaning around a deep margin
• Bite discomfort
• Crown loosening
• Ceramic chipping
• Crown fracture
• Fracture of the underlying tooth
• Recurrent decay
• Aesthetic mismatch
• Gum recession
• Need for repair or replacement

A tooth may occasionally develop pulpal symptoms after crown preparation even when there were no obvious symptoms beforehand. The risk may be greater when the tooth has deep decay, large previous restorations, cracks or a history of trauma.

We explain material limitations and tooth-specific risks before proceeding.

Dental Crown, Onlay, Veneer or Filling?

These treatments solve different problems.

Filling

A filling replaces a localized area of lost tooth structure. It is generally the most conservative option when enough strong tooth remains.

Onlay

An onlay covers one or more weakened cusps without necessarily surrounding the entire tooth.

It may preserve more tooth structure than a conventional full crown in selected cases.

Crown

A crown provides circumferential coverage and is considered when the tooth requires more extensive reinforcement, contour correction or protection.

Veneer

A porcelain veneer covers mainly the visible front surface of a tooth.

It is primarily an aesthetic restoration and is not a substitute for a crown when substantial structural protection is required.

Why Choose MI Dental for Dental Crowns in Kitchener?

Material Selection Based on the Tooth

We do not recommend one material for every patient.

Zirconia, lithium disilicate, PFM and gold each have situations in which they may be appropriate.

Digital Records

Digital scanning and clinical photography can improve communication between the dental office, patient and laboratory.

Attention to the Bite

A crown is not evaluated in isolation. We assess how it contacts the teeth around and opposite it.

Clear Explanations

We explain:

• Why a crown is being recommended
• Whether alternatives are available
• What material is being considered
• What limitations exist
• What to expect during treatment
• How to care for the restoration

Conservative Treatment Planning

We do not believe every heavily filled or cosmetically imperfect tooth automatically requires a crown.

When a filling, onlay, veneer or monitoring approach is more appropriate, that should be part of the discussion.

Ongoing Care

A crown is not considered finished and forgotten. It becomes part of the mouth and must be monitored along with the supporting tooth, gums and bite.

Restore and Protect a Damaged Tooth

A well-planned crown can restore strength, function and appearance to a tooth that might otherwise remain vulnerable to further breakdown.

The success of the treatment depends on more than selecting a material. It begins with a careful diagnosis, a restorable tooth, an appropriate preparation and a crown designed for your bite.

Contact MI Dental to schedule a dental crown consultation in Kitchener.