Dental Asia Sep/Oct 2018

Clinical Feature DENTAL ASIA SEPTEMBER / OCTOBER 2018 34 M ost dentists and orthodontists are aware of the impact thatmouth breathing has on the development of the maxilla. Most are aware of the fact that even after a successful realignment of teeth, unless a retainer is used, relapse usually occurs. The tongue is nature’s retainer and the lateral force exertion of 500 Gm provides the balance required against the inward force pull of the cheek muscles, at around the same force (500 Gm). In an ideal world, these two forces would balance each other and a normal maxillary development would occur. The primary teeth would erupt smoothly and evenly and during the mixed dentition stage there is no overcrowding or misalignment of teeth. of breaths they took per minute and commented t ha t t hey a re breathing for two or three people. I t i s common e n o u g h t o comment about over-eating or drinking, but the breathing is never even noticed. As you will see from the diagram (Fig. 1), normal breathing is a g e n t l e w a v e pa t t e r n , done through the nose at the rate of eight to ten breaths per minute with a minute volume of four to five litres of air. This is always a top-up operation as normal breathing is NEVER a full inhale or full exhale. Normal breathing is initiated when the CO 2 (carbon dioxide) level in the arteries (pACO 2 ) reaches 40mm Hg and stimulates the medullary response at the base of the brain This in turn sends a signal to the diaphragm causing it to contract and relax and the breathing cycle is maintained (Fig. 2). What goes wrong in breathing? The reasons for this are basically threefold and are represented by the coloured arrows above (Fig. 3). Anything that happens to the human body, that the systems resist or reject, sets up a stress response. This stress response, or mini- flight or fight, causes the release of adrenalin from the adrenal glands resulting to the breathing rate to rise. This applies to what we ingest, what stressors we have emotionally and what physical stresses are applied By Dr. Derek Mahony and Mr. Roger Price Introduction At the time we learned the basic physiology during the early part of our careers, we were not able to see its overall importance and how it was all interrelated. It should not come as any surprise that the information that follows will certainly strike a chord and probably elicit the usual comment, “I knew that!” In order to be able to understand what constitutes Dysfunctional Breathing, it is necessary to know what Functional Breathing is. As there is a norm for blood pressure, pulse, temperature, chemical content of the blood etc. so is there a norm for breathing. Unfortunately this norm is not used by the general medical or dental professions. Normal breathing In the 48 years as a Pharmacist, and moving on to many modalities, Mr. Price has seldom come across a doctor who has looked at a patient, counted the number Fig. 1 Fig. 2 Fig. 3