Dental hygienists play a pivotal role in maintaining oral health and educating patients about the long-term impact of their dental decisions. One of the most critical yet often overlooked aspects of this education is the concept of cornerstone teeth.
These teeth serve as key structural supports in the dental arch. Understanding their role and effectively codiagnosing their condition with the dentist can make all the difference in preserving function, esthetics, and overall oral health.
What are cornerstone teeth?
Cornerstone teeth are the first molars and canines. These teeth act as the main support system for the bite and to hold the shape of the arch. They’re essential for several reasons.
First molars: These are among the first permanent teeth to erupt, usually around age six. They establish the foundation for occlusion and play a crucial role in chewing efficiency. In fact, research has shown that first molars experience the highest forces during chewing, underscoring their significant role in the masticatory process.1
Canines: Canines provide important guidance in lateral movements of the jaw, protecting posterior teeth from excessive wear and helping maintain proper alignment.
These teeth are responsible for 70% to 80 % of the chewing process. When a cornerstone tooth is lost or compromised, the entire dentition can suffer from shifting teeth, bone loss, occlusal imbalances, and increased risk of temporomandibular joint (TMJ) disorders.
The additional strain placed on the remaining dentition can accelerate their breakdown, leading to excessive wear, fractures, and/or a high likelihood of needing restorative treatment. Studies have demonstrated that the loss of first molars significantly reduces chewing efficiency, reinforcing their crucial function in mastication.2
The role of hygienists in codiagnosis
Hygienists are often the first providers to notice subtle changes in a patient’s oral health as they spend the most time with patients. This places us in a unique position to collaborate with dentists in codiagnosing problems before they become severe.
Key steps in codiagnosing cornerstone teeth issues
Patient education: This is the most crucial part of our job. We need to be able to explain the function of cornerstone teeth during hygiene visits. Many patients don’t realize that losing a first molar at a young age can lead to lifelong consequences.
Periodontal assessment: We know we should be gathering all our periodontal assessments each visit. If we aren’t checking, how do we know if there’s been a change? These key teeth are often the first to show signs of periodontal disease.
Occlusal analysis: Look for early signs of attrition, fractures, or mobility that might indicate stress on these teeth. Studies confirm that natural dentitions exert the highest occlusal forces on first molars, which emphasizes their essential function in chewing.3
Radiographic review: Identify early bone loss, root fractures, or hidden decay that could compromise a cornerstone tooth.
Communication with the dentist: Present findings in a way that encourages patient engagement. Instead of stating, “There’s a problem,” emphasize why preserving or restoring a cornerstone tooth is essential for overall oral health and discuss the risks of doing nothing.
Preventive and restorative recommendations: Work with the dentist to recommend treatments such as nightguards, occlusal adjustments, periodontal therapy, crowns, or implants to protect or replace cornerstone teeth when necessary.
A lesson in prevention
I’ll discuss a patient in their mid-30s who lost a first molar in their teens and never replaced it. Over time, the adjacent teeth drifted, creating a misaligned bite that led to TMJ discomfort and excessive wear on the remaining dentition. It also led to disuse atrophy and narrowing of the jaw and arch.4
This is a scenario we see too often that can be prevented with early intervention, patient education, and a clear treatment plan. By explaining the role of cornerstone teeth and the consequences of inaction, we can help patients make informed decisions that benefit them for a lifetime.5
The takeaway
Hygienists are integral to the codiagnosis process and play a crucial role in preserving cornerstone teeth. Through thorough assessments, effective communication, and a commitment to patient education, we can help maintain the integrity of these essential teeth and ensure our patients enjoy a lifetime of optimal oral health.
By recognizing cornerstone teeth as the foundation of oral function, we not only elevate our standard of care but also empower patients to take ownership of their overall health. Together with our dental teams, we can make a lasting impact, one cornerstone tooth at a time.
References
- Koc D, Dogan A, Bek B. Bite force and influential factors on bite force measurements: a literature review. Eur J Dent. 2010;4(2):223-232. PMID: 20396457; PMCID: PMC2853825.
- Devlin H, Ferguson MW. Alveolar ridge resorption and mandibular atrophy. A review of the role of local and systemic factors. Br Dent J. 1991;170(3):101-104. doi:10.1038/sj.bdj.4807427
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Akeel R, Nilner M, Nilner K. Masticatory efficiency in individuals with natural dentition. Swed Dent J. 1992;16(5):191-198. PMID: 1481126.
- Rahn AO, Ivanhoe JR, Plummer KD. Textbook of Complete Dentures. PMPH USA. 2009.
- Bourdiol P, Hennequin M, Peyron MA, Woda A. Masticatory adaptation to occlusal changes. Front Physiol. 2020;11(4):263. doi:10.3389/fphys.2020.00263
