Ceramic Crowns and Sleep Bruxism: First Results from a Randomized Trial

Area of Science:

• Dental Materials Science
• Prosthodontics
• Sleep Medicine

Background:

• Sleep bruxism (SB) is a potential risk factor for dental restorations.
• The impact of SB on the longevity of modern ceramic single crowns (SCs) is not fully understood.
• Lithium disilicate (LiDi) and zirconia (Z) are common materials for molar SCs.

Purpose of the Study:

• To evaluate if sleep bruxism (SB) increases technical complications in lithium disilicate (LiDi) or zirconia (Z) molar single crowns (SCs).
• To compare survival and success rates of these SCs in patients with and without SB.

Main Methods:

• A randomized clinical trial involving adult patients classified for SB using questionnaires, clinical signs, and portable electromyography.
• Patients were randomized into four groups: LiDi-SB, LiDi-no SB, Z-SB, and Z-no SB.
• Technical complications, survival, and success rates were assessed one year post-cementation.

Main Results:

• No technical complications (e.g., ceramic defects) were observed in any group.
• Restoration survival rates were high across all groups, with no significant difference between SB and no SB groups for either material.
• Success rates were also comparable between groups, indicating good performance irrespective of bruxism.

Conclusions:

• Within the study's limitations (observation time, sample size), sleep bruxism did not appear to affect the technical complication, survival, or success rates of molar LiDi and Z single crowns.
• Further long-term studies are warranted to confirm these findings.