tips and tricks

The goal for all occlusal therapy is a peaceful neuromusculature. If there is any loss of equilibrium, the muscle will try to regain equilibrium. In a war between teeth and muscle, the teeth will lose. This manifests as tooth wear, mobility, fracture and movement. It is essential to understand the role of the TMJs in occlusal design. As clinicians we must ensure that the TMJ in a reproducible and physiologic position (Centric relation) before the occlusion can be properly assessed and treated. Dawson explains the importance of occlusal harmony by taking a mechanical perspective on the design of the masticatory system. In the design of the teeth, it is important to note that the Jaws and TMJ developed before the occlusion therefore, the occlusion must fit into the preestablished maxillomandibular relationship.Correct phyisologic jaw position must therefore be determined before we can determine the correct alignment and occlusal relationship of the teeth. Th...

Mesioangular lower 8s are generally simpler to extract than vertical or distoangular 8s. The bone present between the mesial surface of the 8 and the distal surface of the 7 whereas with distoangular molars these two teeth are often contacting and a significant periodontal defect can be expected. Distoangular lower 8s often allow the mesial cusps to penetrate the gingiva making it appear a straightforward extraction however they tend to be the most difficult. When raising a flap for a vertical and distoangular molar, you have to release the periosteum all the way to the distal of the tooth. This is to ensure that you have visualised the position of the distal bone. The bone removal must extend to the entire distal portion of the tooth. This is because the distal bone will be supported by the entire ramus and will ensure that the tooth is impossible to elevate out.

Caries that presents as Minor fissure caries but opens into extremely large dentine caries once preparation has started is known as occult caries. Do not be tricked by the narrow nature of the fissure caries, these often are quickly progressing and thus present as soft, light brown, flaky or almost liquidy dentine. You will likely discover these radiographically or due to the clinical presentation of the surrounding enamel being opaque white. Patients are typically teenages or younger because the caries is usually discovered before their 20s one way or another due to its fast progressing nature. Often, these will present in patients with fair oral hygiene. they will often report no symptoms until the pulp is exposed or the enamel cavitates. Possible causes are: -Fluoride bombs: Deep dentine caries occurs through the typical fissure route but due to fluoride exposure, the hydroxyapatite in enamel is replaced by stronger fluorapatite. This results in a strong shell suprastructure that...

A working knowledge of occlusal principles not only improves the planning and execution of full mouth cases but also has an effect on everyday dentistry. It improves the outcomes of: -Patient comfort: with reduction in post operative sensitivity due to high spots and interferences. -Restoration longevity: Due to cracks,or fractures - Occlusal stability: With shifting of teeth, opening of contacts, misalignment -Treatment planning -Esthetics: as form follows function Signs and symptoms of occlusal disease Occlusal disease is defined as the deformation of disturbance of the function of any structures within the masticatory system that are in disequilibrium with a harmounious interrelationship between the TMJs, the masticatory musculature and occluding surfaces of the teeth. Examples include: -Attrition: commonly seen as wear on the lower incisors. there are two common causes of this. Posterior deflections causing an anterior shift from CR into MIP will cause the anterior teeth ...

When examining teeth, apart from from caries, restorations and the periodontal condition, cracks are a common finding, more so the older the patient is. Common places that cracks are seen are the mesial and distal marginal ridges of posterior teeth as well as the mid buccal and lingual grooves. Craze lines are often seen on the labial surface of anterior teeth. Cracks are most commonly seen on mandibular molars, then upper premolars. Teeth more posterior are closer to the muscles of mastication and to the fulcrum point of the TMJ therefore forces tend to be higher on these teeth. Upper molars tend to erupt tipping towards the buccal and the palatal cusps as a result protrude occlusally. These plunger cusps tend to interfere with the lower molars cusps on lateral excursion and predispose to cracks. When a crack is detected, carefully view the level of the posterior occlusal plane in a mouth mirror from the palatal aspect. You should be able to see if a plunger cusp sits above the le...

A general and medical examination of a patient suspected of having sleep disordered breathing is essential in diagnosis. History taking and bed partner questioning can often reveal the potential causes and differential diagnoses even before physical examination and special tests. The manifestations of sleep disordered breathing will be explored in future separate posts. The next post in the series will explore the specific dental signs when screening for obstructive sleep apnoea. Chief complaint Insomnia Often complain their nocturnal sleep is inadequate. Difficulty falling asleep, frequent awakening or early morning awakening with inability to fall asleep. Excessive daytime sleepiness Often complain of drowsiness that interferes with daytime activities and/or unavoidable napping. They may report that they need more sleep at night or there is drowsiness no matter how much sleep is had.They may report poor concentration or irritability. Children may exhibit hyperactivity rather t...

Every health practitioner knows that sinking feeling when they see a certain patient in their appointment book. It is said that the 80/20 rule applies to dentistry: 80% of your problems will come from 20% of your patients. They may be difficult patients due to past history with dentists, unrealistic expectations, clashing of personalities and those odd patients who have had an undesirable outcome in your care and you're managing the sequelae. Patients who have had poor experiences in the past must be handled with care but can slowly be converted into valuable lifelong patients. Those with unrealistic expectations must have their expectations managed before any irreversible treatment is done and if this can't be achieved then you must have a very honest look at your capabilities and pass the patient on if you don't think their goals can be achieved. These are often the ones who come back multiple times for remakes or adjustments and become a further pain in the backside. C...

Dental disease almost always results from a combination of factors rather than just one. The same insult can cause a plethora of different symptoms depending on the resistance of the host and the intensity of the insult. Treating symptoms/effects alone rarely is short sighted and rarely results in satisfactory outcomes. If the cause of the insult can be corrected, the effects usually spontaneously resolve. Repair may be needed after correction but the long term success is greatly enhanced as opposed to only treating the effects. Distinction must be made between contributing effects and causative factors of disease. Contributing factors are those that decrease host resistance or increase function or tension on the system whereas causative factors cause disease.  For example, in a healthy person with a perfect dentition, the introduction of a posterior deflective interference can cause a myriad of effects. 1. The tooth may become sensitive to hot or cold, or it may ache 2. The to...

Heavier plaque accumulation is often noted on the 7s. In class 1 and class 3 occlusions, the distal half of the upper 7s are not in occlusion and in class 2 occlusions, the lower 7s are untouched. This removes the cleansing action of mastication and the fissures are often packed with organic debris as a result. It is prudent to instruct the patient to take their toothbrush further back to the distal surface of the second premolars to clean this area. You can consider Air abrasion or pumice to clear the fissures and placing of a GIC or resin fissure sealant to hinder plaque accumulation. It is also difficult to clean on the buccal surfaces of the molars due to the proximity of the coronoid process. This is why patients often present with large buccal carious lesions on the buccal of the upper 7s and 8s. It may be a sign of salivary dysfunction as the upper molars are adjacent to the parotid salivary duct. Instruct the patient to close their teeth together and brush close mouthed. This...

Sleep disordered breathing is a medical condition that requires a different approach in thinking than the dentistry that we are used to. A solid knowledge of airway anatomy and physiology is essential in understanding and treating OSA. From Sleep medicine 6th edition Numerous factors contribute to ventilation and mechanical properties of the thoracopulmonary system. Because sleep interacts with several of these factors, it has an impact on ventilation and gas exchanges through its effect on airway resistance, thoracopulmonary compliance, and lung volumes. As a consequence of its effect on upper airway muscle control and chest mechanics, sleep has a strong influence on upper airway stability. Accordingly, persons with compromised upper airway anatomy are at increased risk for development of obstructive sleep-induced disordered breathing, especially during the transition between wakefulness and sleep. Anatomy and physiology The upper airway includes the nasal cavity, pharynx and lary...

Take care with interproximal wedging for restorative work in periodontal patients. I was restoring a lower 6 in a patient with minimal recession and deep pocketing and required a wooden wedge to hold the matrix band in place. Care must be taken as the pocket represents a potential space for the wedge to be inserted at the wrong angle into and due to periodontal condition, a larger wedge is often needed. In a cramped space, the wedge often tends to be inserted at an angle too far gingivally. In this case the wedge went deep into the pocket and perforated the lingual gingiva. As the wedge I chose was too small the whole wedge was jammed subgingivally and was very difficult to remove. My tips here are to ensure that a large enough wedge is chosen. If it ever looks like the wedge is too small and the whole wedge would pass through to the other side without too much pressure don't force the wedge in. Also, when positioning the wedge in place, aim slightly occlusally and the contact ...

Let's face it, The majority of the population don't floss daily. I would go so far as to say the majority never floss. Of those who floss regularly, many are not performing the task optimally. I myself was pushed to floss without knowing why but it was just something I did. It wasn't until I was educated as a dentist that my technique had logic behind it. However, in the end, any kind of mechanical cleansing action interdentally is better than no cleaning. Below are some points I consider when educating patients to floss: -Any cleaning is better than nothing. The most superior method of cleaning interdentally is one that the patient will actually do. Don't overcomplicate things and confuse them or they'll lose the motivation to pick up the habit -That's exactly what it is: a habit. Habits are something that have to be trained into you and once they're ingrained in your mind, you won't feel comfortable unless you've flossed your teeth. This is goo...

Treating sleepiness is a big part of why we treat sleep. Many but not all patients with SDB will experience sleepiness. There is definite links to workplace and motor vehicle accidents which affect population morbidity and mortality. Often the patients who experience sleepiness are the quickest to accept treatment plans as they want to improve. Conversely, a person with chronic tiredness may be convinced that their condition is the norm and may be the ones who resist diagnoses and treatment the most. From Sleep medicine 6th edition Sleepiness is a problem reported by 10% to 25% of the population, depending on the definition of sleepiness used and the population sampled. It is most common in young adults and elderly persons. Sleepiness is a physiologic need state like hunger of thirst, with its intensity evident by how rapidly sleep onset occurs, how easily sleep is disrupted, and how long sleep endures. It is normally expressed in a 24 hour cycle related to the light-dark environme...

Everybody learns things differently. Some are visual learners, some rote and some learn by doing. Although I did improve in my study and learning technique over my uni years I am still at a loss as to how to learn effectively and as the years go by I find my attention span shortening no matter the motivation for study. My suggestion would be to try different methods for learning; remove distractions and find your motivation for learning. Question the reasons why you want to learn and what you wish to achieve from further study. For me, big distractions are environment and technology. Finding a quiet place and playing easy music reduce distractions and going back to the humble handwriting is good for technological distractions. Transferring this to a forum like this blog has been good in consolidating knowledge and sieving the knowledge through the act of reading, writing and typing has worked to consolidate the knowledge. I will explore this method further and see if it works long te...

Recently I have been reading a very good textbook: Functional occlusion from TMJ to smile design by Peter Dawson. I am attending a Dr. Michael Melker's Occlusion lecture in August and thought it would be good to do some prereading into the subject. Occlusion and the TMJ is one of many things that are notoriously poorly taught at dental school but are so important to everyday practice. We have to ensure that treatments we are performing on patients are doing benefit and not harm. We have to ensure that we are working towards stability of the orofacial complex and not instability and as patients are even less educated than we are on the subject, we have to take responsibility for our actions because their is a certain level of trust on their part that we should not discount. The concept that Dawson introduces in his textbook is that of "Complete dentistry". It is in essence what some would extend and call call "Holistic dentistry". He urges us to not focus on on...

Sleep disordered breathing (SDB) is only a small fractions of defined sleep disorders. Many people in today's society are physiologically healthy but have factors such as medications, poor sleep hygiene and other lifestyle factors that can affect their sleep. Often we must rule out or treat SDB to realise an improvement in their condition but the optimisation of sleep quality and quantity only comes with treating the person as a whole and assessing the full range of factors that can affect sleep poorly. From Sleep medicine 6th edition Some generalisations about healthy adult sleep • Sleep is entered through NREM sleep. • NREM sleep and REM sleep alternate with a period near 90 minutes. • SWS predominates in the first third of the night and is linked to the initiation of sleep and the length of time awake (i.e., sleep homeostasis).   • REM sleep predominates in the last third of the night and is linked to the circadian rhythm of body temperature. • W...

When restorations are fractured interproximally or debonded and locked into the cavity it can be difficult to floss the rubber dam septa through the contact. This can lead to a failed rubber dam placement or a tear in the dam that will turn into a split if you try and manipulate it further. You can either remove the restoration before rubber dam placement or use a split dam technique. If you clamp the tooth to be restored on the mesial, the clamp can interfere with the matrix system ring and hinder placement. It is frustrating because if the ring is not placed gingivally enough and is above the height of contour it will pull upwards and dislodge the matrix band as well. This is more of an issue clamping premolars and restoring the first premolar or canine as the small mesiodistal width of the clamped tooth means a clamp will overlap the mesial tooth more.To get around this you can can plan to clamp the tooth behind the one being restored or attempt to use a clamp that is less obtrusi...