Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 42 **Bleaching - Stages** 1. Assess the Pulp/Root Canal & Periapical status - **If previous RCF - Re-do if any doubt - i.e. usually!!!** Radiographic comparison of discoloured teeth before and after bleaching procedure ## **Bleaching - Stages** 1. Assess the Pulp/Root Canal & Periapical status - **If previous RCF - Re-do if any doubt - i.e. usually!!!** > [!info] > This is because the quality, materials, and history of the previous treatment are often unknown, and it may be a contributing factor to the discoloration (e.g., from materials like Crypaste). ```mermaid graph TD A[Assess the Pulp/Root Canal & Periapical status] A --> B{Previous RCF?} B -->|Yes| C[Re-do if any doubt - i.e. usually!] C --> D[Remove RCF to below C-EJⁿ] D --> E[Base over RCF - Cavit (allow to set for 1 week)] ``` ```mermaid graph TD A[Assess the Pulp/Root Canal & Periapical status] A --> B{Previous RCF?} B -->|Yes| C[Re-do if any doubt - i.e. usually!] C --> D[Remove RCF to below C-EJⁿ] D --> E[Base over RCF - Cavit (allow to set for 1 week)] > [!tip] Coronal Barrier Details > The gutta-percha should be removed to a depth of **2-3 millimeters below the cemento-enamel junction (CEJ)**. A protective base of **Cavit** is then placed over the gutta-percha. This base should be at least 2mm thick and have a ** ``` **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 44** --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJⁿ - Base over RCF - Cavit - Rubber Dam; Access --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJⁿ - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry **HINT: Use a LIQUID acid etch solution** --- 87 88 ## **Bleaching - Stages** > [!note] Walking Bleach Technique > The internal bleaching process, also known as the **walking bleach technique**, is a multi-stage procedure that begins after the tooth has been successfully root-treated. - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJⁿ - Base over RCF - Cavit - Rubber Dam; Access > [!danger] Crucial Note > It is incorrect and detrimental to remove the discoloured dentine itself, as this would weaken the tooth structure significantly. Only the tooth structure necessary for the initial endodontic access should be removed. **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 45** --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJⁿ - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry - Place thick paste of H₂O₂/Na Perborate --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJⁿ - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry - Place thick paste of H₂O₂/Na Perborate - Temporary filling - Cavit --- 89 90 - Acid etch, wash & dry - **HINT: Use a LIQUID acid etch solution** > [!info] > A liquid etch is easier to apply in the confined space than a gel. Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 46 **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJ - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry - Place thick paste of H₂O₂/Na Perborate - Temporary filling - Cavit - Review after 1 week - Repeat if necessary Diagram illustrating the "Walking Bleach" technique, showing a proximal view of a tooth with labeled components: "Cavit" at the access cavity, "Bleaching Paste" within the pulp chamber, and the root canal space. - Place thick paste of H₂O₂/Na Perborate > [!tip] Paste Preparation and Placement > - A thick, dry paste is mixed using **sodium perborate powder** and **hydrogen peroxide liquid**. > - The paste should be dry enough to be transported to the access cavity using an **amalgam carrier**. > - The paste is packed firmly against the **labial wall** of the pulp chamber. It is not necessary to place it on the palatal wall. - Temporary filling - Cavit > [!info] > A dry cotton pellet can be used to absorb any excess moisture from the bleaching paste. A double layer with IRM is not typically used due to limited space. - Review after 1 week - Repeat if necessary **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 47** --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJ* - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry - Place thick paste of H₂O₂/Na Perborate - Temporary filling - Cavit - Review after 1 week - Repeat if necessary - **Restore access cavity** - *Temporary filling for minimum 2 weeks - Cavit* - *Then do GIC/composite* --- ### **Restoration of Access Cavity** - **“Sandwich technique”** - *McLean J, Br Dent J 1988; 164: 293 - 300* - **GIC - dentine replacement** - **Composite resin - enamel replacement** --- 93 94 - **Restore access cavity** - *Temporary filling for minimum 2 weeks - Cavit* > [!warning] Rationale for Waiting Period > The patient must wait a minimum of **two weeks** because this allows time for any residual oxygen from the hydrogen peroxide to dissipate. Residual oxygen would otherwise inhibit the bond strength of composite and glass ionomer materials. - *Then do GIC/composite* ### **Restoration of Access Cavity** - **“Sandwich technique”** - *McLean J, Br Dent J 1988; 164: 293 - 300* - **GIC - dentine replacement** - **Composite resin - enamel replacement** > [!tip] Clinical Recommendation > It is recommended that the restoring dentist leaves a portion of the Cavit in place as a base over the gutta-percha and also leaves a thin layer of Cavit on the labial wall. This serves two purposes: > 1. It provides a good underlying colour. > 2. It makes access significantly easier if the tooth ever requires re-bleaching in the future. **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 48** --- ### **Bleaching - Stages** - Assess the Pulp/Root Canal & Periapical status - Remove RCF to below C-EJ* - Base over RCF - Cavit - Rubber Dam; Access - Acid etch, wash & dry - Place thick paste of H₂O₂/Na Perborate - Temporary filling - Cavit - Review after 1 week - Repeat if necessary - Restore access cavity - Review - 6 mths, 2-3 yrs, etc --- Clinical and radiographic images showing bleaching progression with red arrows indicating treatment sequence. - Review - 6 mths, 2-3 yrs, etc Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO **Internal Bleaching of Teeth** **- An Analysis of 255 Teeth** Abbott PV, Heah S. **Aust Dent J 2009; 54: 326-333.** 98 2nd Year DMD - 2020 Page 49 Collage of dental images showing discoloured teeth before and after treatment, labeled 97. # **Internal Bleaching of Teeth - An Analysis of 255 Teeth** **Abbott PV, Heah S.** **Aust Dent J 2009; 54: 326-333.** Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO **Materials and Methods** - 200 consecutive patients - 255 teeth internally bleached - Reviewed at regular intervals: - **6 months** - **Then annually up to 5 years** - Photographs taken on Kodachrome 35mm colour transparencies - Patients (and parents) questioned about their perception of the colour changes - Records and photographs reviewed **Factors Assessed** - Patient age, gender - Tooth type - Causative factors - Original colour - Initial outcome of bleaching - Number of appointments required - Colour stability - **6 months & yearly for 5 years** - **Factors related to subsequent changes** - Any subsequent treatment required - Incidence of External Invasive Resorption 2nd Year DMD - 2020 Page 50 ## **Materials and Methods** - 200 consecutive patients - 255 teeth internally bleached - Reviewed at regular intervals: - **6 months** - **Then annually up to 5 years** - Photographs taken on Kodachrome 35mm colour transparencies - Patients (and parents) questioned about their perception of the colour changes - Records and photographs reviewed ## **Factors Assessed** - Patient age, gender - Tooth type - Causative factors - Original colour - Initial outcome of bleaching - Number of appointments required - Colour stability - **6 months & yearly for 5 years** - **Factors related to subsequent changes** - Any subsequent treatment required - Incidence of External Invasive Resorption Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 51 --- **Tooth Discolouration** *Classified according to the CAUSE and COLOUR* - **Trauma** - Pulp haemorrhage - Pulp necrosis (PN) - Pulp canal calcification (PCC) - Previous endodontic materials - **Colour** - Grey - Black - Light Yellow - Dark Yellow --- **Statistical Analyses** - All comparisons were tested for statistical significance - - Pearson’s chi square - One way ANOVA - Scheffe post-hoc test > **ALL** of the following comparisons to be discussed showed significant differences at the 5% level --- 101 102 ## **Tooth Discolouration** *Classified according to the CAUSE and COLOUR* - **Trauma** - Pulp haemorrhage - Pulp necrosis (PN) - Pulp canal calcification (PCC) - Previous endodontic materials - **Colour** - Grey - Black - Light Yellow - Dark Yellow ## **Statistical Analyses** - All comparisons were tested for statistical significance - - Pearson’s chi square - One way ANOVA - Scheffe post-hoc test > **ALL** of the following comparisons to be discussed showed significant differences at the 5% level Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 52 **Results** <table> <thead> <tr> <th></th> <th>1 tooth</th> <th>2 teeth</th> <th>3 teeth</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Males</td> <td>72</td> <td>12</td> <td>7</td> <td>117 (46%)</td> </tr> <tr> <td>Females</td> <td>90</td> <td>18</td> <td>4</td> <td>138 (54%)</td> </tr> <tr> <td>Total</td> <td>162</td> <td>30</td> <td>11</td> <td>255 (100%)</td> </tr> </tbody> </table> **More males than most studies due to higher incidence of trauma in boys than girls** **Age Range** Bar chart showing number of patients across age ranges: <10, 11-20, 21-30, 31-40, 41-50, 51-60. The 11-20 age group has the highest number of patients, peaking above 100. # **Results** <table> <thead> <tr> <th></th> <th>1 tooth</th> <th>2 teeth</th> <th>3 teeth</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Males</td> <td>72</td> <td>12</td> <td>7</td> <td>117 (46%)</td> </tr> <tr> <td>Females</td> <td>90</td> <td>18</td> <td>4</td> <td>138 (54%)</td> </tr> <tr> <td>Total</td> <td>162</td> <td>30</td> <td>11</td> <td>255 (100%)</td> </tr> </tbody> </table> **More males than most studies due to higher incidence of trauma in boys than girls** ## **Age Range** - ==The majority of patients were in the **11-20 year old age group**, which is consistent with the high incidence of dental trauma in this demographic.== - ==However, the procedure was successfully performed across a wide range of ages, from under 10 to over 50.== Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 53 Tooth Type <table> <thead> <tr> <th>Maxillary</th> <th>Tooth</th> <th>Mandibular</th> </tr> </thead> <tbody> <tr> <td>1 (0.4%)</td> <td>1<sup>st</sup> Premolar</td> <td>-</td> </tr> <tr> <td>5 (2.0%)</td> <td>Canine</td> <td>-</td> </tr> <tr> <td>52 (20.4%) ★</td> <td>Lateral Incisor</td> <td>4 (1.6%)</td> </tr> <tr> <td>176 (69%) ★</td> <td>Central Incisor</td> <td>17 (6.6%)</td> </tr> <tr> <td>234 (91.3%)</td> <td>Totals</td> <td>21 (8.2%)</td> </tr> </tbody> </table> Colour -v- Cause <table> <thead> <tr> <th></th> <th>Trauma</th> <th>Previous Endo</th> <th>PCC</th> <th>Pulp Necrosis</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Dark Yellow</td> <td>8.6 %</td> <td>11.4 % ★</td> <td>2.7 % ★</td> <td>7.4 % ★</td> <td>30.2 %</td> </tr> <tr> <td>Light Yellow</td> <td>15.3</td> <td>3.9</td> <td>0.8</td> <td>3.1</td> <td>23.1</td> </tr> <tr> <td>Grey</td> <td>26.7 ★</td> <td>4.3</td> <td>0</td> <td>1.6</td> <td>32.6</td> </tr> <tr> <td>Black</td> <td>8.2</td> <td>4.3</td> <td>0</td> <td>1.6</td> <td>14.1</td> </tr> <tr> <td>Total</td> <td>58.8</td> <td>23.9</td> <td>3.6</td> <td>13.7</td> <td>100</td> </tr> </tbody> </table> ## **Tooth Type** <table> <thead> <tr> <th>Maxillary</th> <th>Tooth</th> <th>Mandibular</th> </tr> </thead> <tbody> <tr> <td>1 (0.4%)</td> <td>1<sup>st</sup> Premolar</td> <td>-</td> </tr> <tr> <td>5 (2.0%)</td> <td>Canine</td> <td>-</td> </tr> <tr> <td>52 (20.4%) ★</td> <td>Lateral Incisor</td> <td>4 (1.6%)</td> </tr> <tr> <td>176 (69%) ★</td> <td>Central Incisor</td> <td>17 (6.6%)</td> </tr> <tr> <td>234 (91.3%)</td> <td>Totals</td> <td>21 (8.2%)</td> </tr> </tbody> </table> ## **Colour -v- Cause** <table> <thead> <tr> <th></th> <th>Trauma</th> <th>Previous Endo</th> <th>PCC</th> <th>Pulp Necrosis</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Dark Yellow</td> <td>8.6 %</td> <td>11.4 % ★</td> <td>2.7 % ★</td> <td>7.4 % ★</td> <td>30.2 %</td> </tr> <tr> <td>Light Yellow</td> <td>15.3</td> <td>3.9</td> <td>0.8</td> <td>3.1</td> <td>23.1</td> </tr> <tr> <td>Grey</td> <td>26.7 ★</td> <td>4.3</td> <td>0</td> <td>1.6</td> <td>32.6</td> </tr> <tr> <td>Black</td> <td>8.2</td> <td>4.3</td> <td>0</td> <td>1.6</td> <td>14.1</td> </tr> <tr> <td>Total</td> <td>58.8</td> <td>23.9</td> <td>3.6</td> <td>13.7</td> <td>100</td> </tr> </tbody> </table> **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 54** --- ### **Colour -v- Cause** - **Trauma** - Grey, Light Yellow - **Previous Endo** - Dark Yellow - **PCC** - Dark Yellow - **PN** - Dark Yellow --- ### **Initial Outcome of Bleaching** <table> <thead> <tr> <th></th> <th>DY</th> <th>LY</th> <th>Grey</th> <th>Black</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Good</td> <td>67.5 %</td> <td>94.9 %</td> <td>100 %</td> <td>86.1 %</td> <td>87.1 %</td> </tr> <tr> <td>Acceptable</td> <td>32.5</td> <td>5.1</td> <td>-</td> <td>13.9</td> <td>12.9</td> </tr> <tr> <td>No Change</td> <td>-</td> <td>-</td> <td>-</td> <td>-</td> <td>-</td> </tr> <tr> <td>Total</td> <td>100</td> <td>100</td> <td>100</td> <td>100</td> <td>100</td> </tr> </tbody> </table> --- 107 108 ### **Colour -v- Cause** - **Trauma** - Grey, Light Yellow - **Previous Endo** - Dark Yellow - **PCC** - Dark Yellow - **PN** - Dark Yellow ### **Initial Outcome of Bleaching** > [!info] Outcome Definitions > - **Good:** Excellent colour match; operator and patient very happy (87.1% of cases). > - **Acceptable:** Significant improvement, but not a perfect match (12.9% of cases). > - **No Change:** No cases resulted in <table> <thead> <tr> <th></th> <th>DY</th> <th>LY</th> <th>Grey</th> <th>Black</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>Good</td> <td>67.5 %</td> <td>94.9 %</td> <td>100 %</td> <td>86.1 %</td> <td>87.1 %</td> </tr> <tr> <td>Acceptable</td> <td>32.5</td> <td>5.1</td> <td>-</td> <td>13.9</td> <td>12.9</td> </tr> <tr> <td>No Change</td> <td>-</td> <td>-</td> <td>-</td> <td>-</td> <td>-</td> </tr> <tr> <td>Total</td> <td>100</td> <td>100</td> <td>100</td> <td>100</td> <td>100</td> </tr> </tbody> </table> # Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO ## Outcome -v- Colour * Predictability of outcome: - **Grey** (most predictable) - **Light Yellow** - **Black** - **Dark Yellow** (least predictable) ## Colour and Number of Applications of Bleach <table> <thead> <tr> <th>No. of Applications</th> <th>DY</th> <th>LY</th> <th>Grey</th> <th>Black</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>5.2 %</td> <td>74.6 %</td> <td>73.5 %</td> <td>25.0 %</td> <td>46.3 %</td> </tr> <tr> <td>2</td> <td>35.0</td> <td>18.6</td> <td>21.7</td> <td>50.0</td> <td>29.0</td> </tr> <tr> <td>3</td> <td>37.7</td> <td>5.1</td> <td>2.4</td> <td>13.9</td> <td>15.3</td> </tr> <tr> <td>4</td> <td>18.2</td> <td>1.7</td> <td>2.4</td> <td>8.3</td> <td>7.8</td> </tr> <tr> <td>5</td> <td>3.9</td> <td>-</td> <td>-</td> <td>-</td> <td>1.2</td> </tr> <tr> <td>10</td> <td>-</td> <td>-</td> <td>-</td> <td>2.8</td> <td>0.4</td> </tr> </tbody> </table> 2nd Year DMD - 2020 Page 55 ## **Outcome -v- Colour** * Predictability of outcome: - **Grey** (most predictable) - **Light Yellow** - **Black** - **Dark Yellow** (least predictable) > [!success] Conclusion > Gray and light yellow stains are the most predictable to treat, while dark yellow is the most difficult, though still yielding a good or acceptable result in all cases. ## **Colour and Number of Applications of Bleach** <table> <thead> <tr> <th>No. of Applications</th> <th>DY</th> <th>LY</th> <th>Grey</th> <th>Black</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>5.2 %</td> <td>74.6 %</td> <td>73.5 %</td> <td>25.0 %</td> <td>46.3 %</td> </tr> <tr> <td>2</td> <td>35.0</td> <td>18.6</td> <td>21.7</td> <td>50.0</td> <td>29.0</td> </tr> <tr> <td>3</td> <td>37.7</td> <td>5.1</td> <td>2.4</td> <td>13.9</td> <td>15.3</td> </tr> <tr> <td>4</td> <td>18.2</td> <td>1.7</td> <td>2.4</td> <td>8.3</td> <td>7.8</td> </tr> <tr> <td>5</td> <td>3.9</td> <td>-</td> <td>-</td> <td>-</td> <td>1.2</td> </tr> <tr> <td>10</td> <td>-</td> <td>-</td> <td>-</td> <td>2.8</td> <td>0.4</td> </tr> </tbody> </table> **Discoloured Teeth - 1 & 2** W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 56 ### Colour and Number of Applications of Bleach **Light Yellow (least)** Grey Black **Dark Yellow (most)** ~ ½ needed only ONE application ~ ⅓ needed TWO applications ~ ¼ needed 3 - 5 applications ### Cause and Number of Applications of Bleach <table> <thead> <tr> <th>No. of Applications</th> <th>Trauma</th> <th>Previous Endo</th> <th>PCC</th> <th>PN</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>62.7 %</td> <td>24.6 %</td> <td>11.1 %</td> <td>22.9 %</td> <td>46.3 %</td> </tr> <tr> <td>2</td> <td>27.3</td> <td>32.8</td> <td>22.2</td> <td>31.4</td> <td>29.0</td> </tr> <tr> <td>3</td> <td>8.0</td> <td>16.4</td> <td>44.5</td> <td>37.1</td> <td>15.3</td> </tr> <tr> <td>4</td> <td>2.0</td> <td>21.3</td> <td>22.2</td> <td>5.7</td> <td>7.8</td> </tr> <tr> <td>5</td> <td>-</td> <td>3.3</td> <td>-</td> <td>2.9</td> <td>1.2</td> </tr> <tr> <td>10</td> <td>-</td> <td>1.6</td> <td>-</td> <td>-</td> <td>0.4</td> </tr> </tbody> </table> ### **Colour and Number of Applications of Bleach** **Light Yellow (least)** Grey Black **Dark Yellow (most)** ~ ½ needed only ONE application ~ ⅓ needed TWO applications ~ ¼ needed 3 - 5 applications ### **Cause and Number of Applications of Bleach** <table> <thead> <tr> <th>No. of Applications</th> <th>Trauma</th> <th>Previous Endo</th> <th>PCC</th> <th>PN</th> <th>Total</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>62.7 %</td> <td>24.6 %</td> <td>11.1 %</td> <td>22.9 %</td> <td>46.3 %</td> </tr> <tr> <td>2</td> <td>27.3</td> <td>32.8</td> <td>22.2</td> <td>31.4</td> <td>29.0</td> </tr> <tr> <td>3</td> <td>8.0</td> <td>16.4</td> <td>44.5</td> <td>37.1</td> <td>15.3</td> </tr> <tr> <td>4</td> <td>2.0</td> <td>21.3</td> <td>22.2</td> <td>5.7</td> <td>7.8</td> </tr> <tr> <td>5</td> <td>-</td> <td>3.3</td> <td>-</td> <td>2.9</td> <td>1.2</td> </tr> <tr> <td>10</td> <td>-</td> <td>1.6</td> <td>-</td> <td>-</td> <td>0.4</td> </tr> </tbody> </table> **Discoloured Teeth - 1 & 2** W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 57 --- ### Cause and Number of Applications of Bleach - **Trauma - Significantly less** § Usually only ONE appointment - **Others - No sig. difference** - PCC: 2-4 appointments - PN: 1-3 appointments - Previous Endo: 1-3 appointments (but ?? up to 10) --- ### Recall Attendance <table> <thead> <tr> <th></th> <th>Due</th> <th>Attended</th> <th>% Attended</th> </tr> </thead> <tbody> <tr> <td>6 mths</td> <td>166</td> <td>130</td> <td>78.3</td> </tr> <tr> <td>1 yr</td> <td>24</td> <td>24</td> <td>100</td> </tr> <tr> <td>2 yrs</td> <td>82</td> <td>53</td> <td>64.6</td> </tr> <tr> <td>3 yrs</td> <td>37</td> <td>30</td> <td>81.1</td> </tr> <tr> <td>4 yrs</td> <td>24</td> <td>17</td> <td>70.8</td> </tr> <tr> <td>5 yrs</td> <td>11</td> <td>9</td> <td>81.8</td> </tr> </tbody> </table> ### **Cause and Number of Applications of Bleach** - **Trauma - Significantly less** - § Usually only ONE appointment - **Others - No sig. difference** - PCC: 2-4 appointments - PN: 1-3 appointments - Previous Endo: 1-3 appointments (but ?? up to 10) ### **Recall Attendance** <table> <thead> <tr> <th></th> <th>Due</th> <th>Attended</th> <th>% Attended</th> </tr> </thead> <tbody> <tr> <td>6 mths</td> <td>166</td> <td>130</td> <td>78.3</td> </tr> <tr> <td>1 yr</td> <td>24</td> <td>24</td> <td>100</td> </tr> <tr> <td>2 yrs</td> <td>82</td> <td>53</td> <td>64.6</td> </tr> <tr> <td>3 yrs</td> <td>37</td> <td>30</td> <td>81.1</td> </tr> <tr> <td>4 yrs</td> <td>24</td> <td>17</td> <td>70.8</td> </tr> <tr> <td>5 yrs</td> <td>11</td> <td>9</td> <td>81.8</td> </tr> </tbody> </table> **Discoloured Teeth - 1 & 2** W/Prof. Paul V. Abbott AO 2nd Year DMD - 2020 Page 58 ### Colour Stability <table> <thead> <tr> <th>Original Colour</th> <th>Initial Result</th> <th>Original No.</th> <th>Acceptable Change</th> <th>Discoloured</th> </tr> </thead> <tbody> <tr> <td><strong>DY</strong></td> <td>Good</td> <td>52</td> <td>2 (3.8%)<br>(2 yrs, 3 yrs)</td> <td>2 (3.8%)<br>(6 mths, 3 yrs)</td> </tr> <tr> <td><strong>DY</strong></td> <td>Acceptable</td> <td>25</td> <td>-</td> <td>2 (8%)<br>(6 mths, 1 yr)</td> </tr> <tr> <td><strong>LY</strong></td> <td>Good</td> <td>56</td> <td>1 (1.8%)<br>(4 yrs)</td> <td>-</td> </tr> <tr> <td><strong>LY</strong></td> <td>Acceptable</td> <td>3</td> <td>-</td> <td>-</td> </tr> </tbody> </table> 115 ### Colour Stability <table> <thead> <tr> <th>Original Colour</th> <th>Initial Result</th> <th>Original No.</th> <th>Acceptable Change</th> <th>Discoloured</th> </tr> </thead> <tbody> <tr> <td><strong>BLACK</strong></td> <td>Good</td> <td>31</td> <td>-</td> <td>1 (3%)<br>(3 yrs)</td> </tr> <tr> <td><strong>BLACK</strong></td> <td>Acceptable</td> <td>5</td> <td>-</td> <td>-</td> </tr> <tr> <td><strong>GREY</strong></td> <td>Good</td> <td>83</td> <td>1 (1.2%)<br>(4 yrs)</td> <td>1 (1.2%)<br>(5 yrs)</td> </tr> <tr> <td><strong>GREY</strong></td> <td>Acceptable</td> <td>-</td> <td>-</td> <td>-</td> </tr> </tbody> </table> 116 2nd Year DMD - 2020 Page 58 ### **Colour Stability** <table> <thead> <tr> <th>Original Colour</th> <th>Initial Result</th> <th>Original No.</th> <th>Acceptable Change</th> <th>Discoloured</th> </tr> </thead> <tbody> <tr> <td><strong>DY</strong></td> <td>Good</td> <td>52</td> <td>2 (3.8%)<br>(2 yrs, 3 yrs)</td> <td>2 (3.8%)<br>(6 mths, 3 yrs)</td> </tr> <tr> <td><strong>DY</strong></td> <td>Acceptable</td> <td>25</td> <td>-</td> <td>2 (8%)<br>(6 mths, 1 yr)</td> </tr> <tr> <td><strong>LY</strong></td> <td>Good</td> <td>56</td> <td>1 (1.8%)<br>(4 yrs)</td> <td>-</td> </tr> <tr> <td><strong>LY</strong></td> <td>Acceptable</td> <td>3</td> <td>-</td> <td>-</td> </tr> <tr> <td><strong>BLACK</strong></td> <td>Good</td> <td>31</td> <td>-</td> <td>1 (3%)<br>(3 yrs)</td> </tr> <tr> <td><strong>BLACK</strong></td> <td>Acceptable</td> <td>5</td> <td>-</td> <td>-</td> </tr> <tr> <td><strong>GREY</strong></td> <td>Good</td> <td>83</td> <td>1 (1.2%)<br>(4 yrs)</td> <td>1 (1.2%)<br>(5 yrs)</td> </tr> <tr> <td><strong>GREY</strong></td> <td>Acceptable</td> <td>-</td> <td>-</td> <td>-</td> </tr> </tbody> </table> **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 59** --- ### **Colour Stability - Overall** - **Acceptable Change - 4 teeth (1.6%)** - 2 x DY, 1 x LY, 1 x Grey - **Discoloured - 6 teeth (2.4%)** - 2 x DY, 2 x LY, 1 x Black, 1 x Grey - **Total - 10 teeth (3.9%)** --- ### **Teeth Discoloured Again** - **Still acceptable** - 1 @ 2 yrs: - 1 @ 3 yrs: **unsatisfactory restorations** - 2 @ 4 yrs: - **Needed bleaching again** - 2 @ 6 mths: access not restored - 1 @ 1 yr: - 2 @ 3 yrs: **unsatisfactory restorations** - 1 @ 5 yrs: - **NB - Cotton wool found in ALL these cases** ### **Colour Stability - Overall** - **Acceptable Change - 4 teeth (1.6%)** - 2 x DY, 1 x LY, 1 x Grey - **Discoloured - 6 teeth (2.4%)** - 2 x DY, 2 x LY, 1 x Black, 1 x Grey - **Total - 10 teeth (3.9%)** ### **Teeth Discoloured Again** > [!failure] Cause of Re-Discoloration > A critical finding was that subsequent discoloration was **not a reversal of the chemical bleaching reaction**. In all cases that required re-bleaching, the cause was found to be **leakage from unsatisfactory coronal restorations**. This highlights that re-discoloration is a **new staining event** caused by microleakage. - **Still acceptable** - 1 @ 2 yrs: - 1 @ 3 yrs: **unsatisfactory restorations** - 2 @ 4 yrs: - **Needed bleaching again** - 2 @ 6 mths: access not restored - 1 @ 1 yr: - 2 @ 3 yrs: **unsatisfactory restorations** - 1 @ 5 yrs: - **NB - Cotton wool found in ALL these cases** **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 60** --- ### **Other Observations** - Age was not related to the: - **Cause** - **Colour** - **No. of appointments** --- ### **Other Observations** - Restorations: - **GIC/Comp.** - Colour was more stable - **Cotton wool** - was found in the access cavities of **ALL** cases with further discolouration --- 119 120 ### **Other Observations** - Age was not related to the: - **Cause** - **Colour** - **No. of appointments** - Restorations: - **GIC/Comp.** - Colour was more stable - **Cotton wool** - was found in the access cavities of **ALL** cases with further discolouration > [!warning] The **Discoloured Teeth - 1 & 2** **W/Prof. Paul V. Abbott AO** **2nd Year DMD - 2020** **Page 61** --- ### **Other Observations** - **NO cases were found with External Invasive Resorption at any review appointments** - **82% of cases reviewed for 5 years** - **But: ?? may need more time to assess** --- ### **Further Management Needed** - **Re-bleached - 6 teeth** - *Restoration breakdown - as discussed* - **Extraction - 5 teeth** - *Perio, HRF, VRF, C-RF, Repl. Res.* - **Crowns - 4 teeth** - *Crown fractures* - **Veneers - 3 teeth** - *One tooth too light* - *Two had old veneers replaced* --- 121 122 - **NO cases were found with External Invasive Resorption at any review appointments** > [!info] > This may be due to the careful placement of the protective Cavit base over the root filling. - **82% of cases reviewed for 5 years** - **But: ?? may need more time to assess** ### **Further Management Needed** - **Re-bleached - 6 teeth** - *Restoration breakdown - as discussed* - **Extraction - 5 teeth** - *Perio, HRF, VRF, C-RF, Repl. Res.* - **Crowns - 4 teeth** - *Crown fractures* - **Veneers - 3 teeth** - *One tooth too light* - *Two had old veneers replaced* Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO --- **Conclusions from this Study** - Internal bleaching is a predictable procedure - Initial colour change was usually “good” - The rest were “acceptable” - Easier to bleach: - Teeth stained after trauma - Grey or Light yellow discolourations - Darker teeth need more bleaching appointments - Dark yellow is the most difficult to bleach - Difficult to remove stains from previous RF materials - Some teeth discolour again over 2-5 years - Appears to be related to breakdown of the restoration --- **Overall Conclusions** - Internal bleaching - predictable, simple, quick, cheap - Biologically cheap: - Conserves tooth structure - Maintain natural contour, form, function, occlusion - Avoids potential problems of prostheses: - Periodontal problems, occlusion changes, use of posts, root fractures, opposing tooth wear, unnatural appearance, colour change of adjacent teeth with age, etc - Safe if adequate precautions are taken - Essential to know and understand the chemistry of the materials and the procedural steps required --- 2nd Year DMD - 2020 Page 62 # **Conclusions** ### **Conclusions from this Study** - Internal bleaching is a predictable procedure - Initial colour change was usually “good” - The rest were “acceptable” - Easier to bleach: - Teeth stained after trauma - Grey or Light yellow discolourations - Darker teeth need more bleaching appointments - Dark yellow is the most difficult to bleach - Difficult to remove stains from previous RF materials - ==Some teeth discolour again over 2-5 years== - ==Appears to be related to breakdown of the restoration, not a reversal of the bleaching process.== - Some teeth discolour again over 2-5 years - Appears to be related to breakdown of the restoration ### **Overall Conclusions** - Internal bleaching - predictable, simple, quick, cheap - Biologically cheap: - Conserves tooth structure - Maintain natural contour, form, function, occlusion - Avoids potential problems of prostheses: - Periodontal problems, occlusion changes, use of posts, root fractures, opposing tooth wear, unnatural appearance, colour change of adjacent teeth with age, etc - Safe if adequate precautions are taken - Essential to know and understand the chemistry of the materials and the procedural steps required > [!danger] Safety First > - Use of **safety glasses** for the patient and clinical team is mandatory. > - A **rubber dam** must be used to protect soft tissues from chemical burns. Discoloured Teeth - 1 & 2 W/Prof. Paul V. Abbott AO 125 2nd Year DMD - 2020 Page 63 Clinical photograph showing discoloured anterior teeth, likely demonstrating internal and/or external staining. # **Discoloured Teeth - 1 & 2** ## **W/Prof. Paul V. Abbott AO** ### **Additional instructions** This lecture contains lots of graphical figures and study results. For grahpical figures omit any mention unless it can be used to add context to the exsiting text. For academic studies, their results should be summarized into 1 or 2 key points maximum (as they often contain unneccessary informat). [[6b Discoloured teeth.pdf#page=1|6b Discoloured teeth, p.1]] [[6b Discoloured teeth.pdf#page=2|6b Discoloured teeth, p.2]] [[6b Discoloured teeth.pdf#page=3|6b Discoloured teeth, p.3]] [[6b Discoloured teeth.pdf#page=4|6b Discoloured teeth, p.4]] [[6b Discoloured teeth.pdf#page=5|6b Discoloured teeth, p.5]] [[6b Discoloured teeth.pdf#page=6|6b Discoloured teeth, p.6]] [[6b Discoloured teeth.pdf#page=7|6b Discoloured teeth, p.7]] [[6b Discoloured teeth.pdf#page=8|6b Discoloured teeth, p.8]] [[6b Discoloured teeth.pdf#page=9|6b Discoloured teeth, p.9]] [[6b Discoloured teeth.pdf#page=10|6b Discoloured teeth, p.10]] [[6b Discoloured teeth.pdf#page=11|6b Discoloured teeth, p.11]] [[6b Discoloured teeth.pdf#page=12|6b Discoloured teeth, p.12]] [[6b Discoloured teeth.pdf#page=13|6b Discoloured teeth, p.13]] [[6b Discoloured teeth.pdf#page=14|6b Discoloured teeth, p.14]] [[6b Discoloured teeth.pdf#page=15|6b Discoloured teeth, p.15]] [[6b Discoloured teeth.pdf#page=16|6b Discoloured teeth, p.16]] [[6b Discoloured teeth.pdf#page=17|6b Discoloured teeth, p.17]] [[6b Discoloured teeth.pdf#page=18|6b Discoloured teeth, p.18]] [[6b Discoloured teeth.pdf#page=19|6b Discoloured teeth, p.19]] [[6b Discoloured teeth.pdf#page=20|6b Discoloured teeth, p.20]] [[6b Discoloured teeth.pdf#page=21|6b Discoloured teeth, p.21]] [[6b Discoloured teeth.pdf#page=22|6b Discoloured teeth, p.22]]