Orthodontic Tooth Movement: Ideal Rate and Force

Orthodontic Tooth Movement: Ideal Rate and Force Ananth Kadekodi â€Å"Describe and discuss the concept of the ideal rate and force for Orthodontic tooth movement. Provide evidence for and against the claims of this ideal†. Orthodontic tooth movement is a process that combines pathologic, physiologic and biological responses to externally applied forces (Wise, King, 2008). It is explained by the pressure tension theory and bone bending theory. Pressure tension theory states that tooth movement occurs in the periodontal space by creating a pressure side and a tension side (Schwarz, 1932). Conversely, bone bending theory states that force delivered, results in bending of the tooth and its surrounding structure, whilst altering the cellular activity for bone remodelling. Additionally, tooth movement is also comprised of three phases, which include the initial phase, lag phase and post lag phase (Burstone, 1962). Currently, there is being a shift, from the emphasis on force application to the biological and biochemical factors affecting tooth movement (Mayne, 2014). Nevertheless, understanding of the force magnitude and its temporal characteristics is important determining the ideal rate and force of ortho dontic tooth movement. Study conducted by various scientists, showed that variables such as: force magnitude; continuous vs intermittent force; individual variations; tooth variations and different types of tooth movement play a role in determining the ideal and rate and force of tooth movement. Studies by Hixon et al. (1970) showed that higher forces moved teeth farther in 8 weeks than lighter forces. The studies showed an increase in maxillary canine movement in all but one of the subjects. The trials demonstrated that as the force increased from 200 grams to 300 grams, the tooth movement for patient B increased from 0.15 mm/week to 0.25 mm/week. This is a result of the higher forces generating a metabolic response sooner and at a more rapid rate, resulting in an increased tooth movement. Additionally, study conducted by Andreasen, and Johnson (1967) on sixteen females, showed teeth exposed to the 400 grams moved further than 200 gm, at a rate of 2.5 times to that of the lower force. Moreover, heavier force, also cause an increased anchor teeth movement (Storey, 1973). However, studies by Owman-moll, Kurol, and Lundgren (1996) have claimed that maximum tooth movement can be achieved even with light forces. This is also supported by Storey (1973), who stated little differen ces in canine movement between heavy and light forces. Moreover, Ren, Maltha, Kuijpers-Jagtman (2003) support this viewpoint by stating that, there is no specific optimal force but a wide range of forces evoke a biological response in the periodontal tissue for ideal tooth movement. Additionally, Owman-moll et al. (1996) through their studies showed that, while heavy forces increase tooth movement, they can also damage the tooth and increase the rate of root resorption. Storey (1973) observed that some trauma is associated even with applied light orthodontic forces. In order to produce adequate biological response in the periodontium, light forces cause frontal bone resorption but heavy forces can cause PDL necrosis, along with bone and root resorption (Krishnan, Davidovich, 2006). Hence, an optimal force is an extrinsic mechanical stimulus, with the aim of restoring the equilibrium of periodontal supporting tissue remodelling via cellular response. It should lead to a maximum rate of tooth movement, while ensuring minimal irreversible root, PDL and alveolar bone damage. Also, this force should produce a maximum rate of tooth movement, whilst ensuring patient comfort (Proffit, Fields, Sarver, 2013; Ren at al., 2003). Teeth react differently, depending on whether the force is continuous or intermittent. Studies by Oates, Moore, and Caputo (1978) showed tooth movement exposed to low level of intermittent tooth forces were equal to that of continuous forces. But at higher force levels, intermittent forces produce greater tooth movement within a shorter period of time. However, results from study conducted by Owman-Moll, Kurol, and Lundgren (1995) showed continuous forces (4.3mm +/- 1.5mm) were more effective than intermittent forces (2.9 +/- 0.6mm) in achieving tooth movement. Furthermore, the study also showed no significant root resorption differences between the two forces in the end. Proffit et al. (2013) believe that effective tooth movement occurs with longer and continuous forces between 4 – 8 hours. They also believe that light continuous forces produce the best tooth movement and these forces should be light enough to ensure only frontal resorption. However, heavy continuous forces s hould be avoided due to tissue damage but heavy intermittent force is clinically acceptable although it is less efficient. Study conducted by Hixon et al. (1970) showed the role of individual variation affecting tooth movement, with some individuals displaying increased movement than others. These individual variations are in regard with different root areas, metabolic responses and facial growth. The variations resulted in altered time and rate of tooth movement between individuals. Additionally, older patients with lower metabolism and increased facial growth showed less movement, in comparison to a younger patient. The variation is also attributed to differences in tissue characteristics. The younger patients have many celled periodontal membrane; uncalcified osteoid bone crest lining; and loose fibrous marrow space tissue, meaning that they reach the proliferation stage of tissue changes earlier than older adults. This will result in tooth movement (initial phase) starting earlier in younger people (Reitan, 1957). Additionally, Pilon, Kuijpers-Jagtman, and Maltha (1996), stated that individual differ ences in bone density, metabolism and PDL turnover can also be responsible for the variations. Each individual has his/her optimum pressure for tooth movement and that in slow movers; the optimum forces were not applied. Hixon et al. (1970), though his study demonstrated different teeth having different optimal rates and force for tooth movement. The results noted an increased canine movement, in comparison to molars. This is due to the root surface area of the canine being lesserthan molar, with the forces being distributed over a larger area rather than being concentrated (in the case with canines). Moreover, Proffit et al. (2013) also support this theory through their table, which shows a smaller force for anterior teeth and a larger force for posteriors. Additionally, Smith and Storey (1952) stated the optimum range for the maximum rate of movement is 150-200cN for canines with later studies by Lee (1964) increasing the range to 260cN. Through their studies, Lundgren, Ownman-Moll, and Kurol (1996) stated the ideal rate of horizontal tooth crown movement was 0.8 mm during the first week and 3.7mm after 7 weeks. However, intraoral location also makes a difference, with maxillary canines having an i ncreased movement in comparison to their mandibular counterparts (Hixon et al., 1970). However, Ren, Maltha, and Van‘t Hof (2003) stated no differences in movement between the maxillary and mandibular canines. Hence, the implications of intraoral location on tooth movement are still unclear. Proffit et al. (2013) have stated that different types of tooth movement have different optimal forces and these include: tipping movement (35-60 gm); translation (70-120 gm); root uprighting (50-100gm); rotation (35-60 gm); extrusion (35-60gm) and intrusion (10-20 gm). Using results from past studies, along with the consideration of the above variables, Quinn, and Yoshikawa (1985) have developed four hypotheses, related to force application and tooth movement. Hypothesis 1 is a constant relationship and Hypothesis 2, is linear relationship between the rate of tooth movement and stress. Hypothesis 3 states that increasing stress increases the rate of tooth movement to a maximum after which the rate declines with additional stress. Lastly, hypothesis 4 states that tooth movement increases with stress up to a point after which additional stress causes no increase in tooth movement. Quinn and Yoshikawa support hypothesis 4, as it supported by extensive experimental and clinical data. This hypothesis is also supported by Hixon et al., with his results showing a lack of tooth movement after a certain force application. But Ren, Maltha, and Van‘t Hof (2003), challenged this model due to a lock of available data with high forces, and created a new ma thematical model, where shows no tooth movement with no force, but as the force increases, the movement also increases until a certain force, after which the movement stays constant or slightly decreases but will never become negative. This is in contrast to hypothesis 4, which stated the movement as being constant but never decreasing. From the above essay, we can see that there is still a lack of definite answer for an ideal force and rate of tooth movement, and this can attributed to four main reasons. The first reason is due to a lack of ability to calculate stress and strain at the periodontal ligament. Most studies discussed above, were based on the application of the force to the tooth, but not the forces leading to biological reactions. The second reason is due to the lack of tooth movement control, with most studies involving tooth tipping which causes uneven stress distribution in periodontal ligament. Moreover, measurements are made at the crown, and not at the stress areas, resulting in force overestimation. Additionally, many of the studies were conducted during a short period of time, making the data relevant only for the first two phases of tooth movement. Lastly, variation both among and within individuals, makes it difficult to calculate optimal force and rate, as each individual has his/her individ ualised optimal values (Ren, Maltha, Kuijpers-Jagtman, 2003). In conclusion, we can see that more studies need to be conducted to determine the ideal rate and force of orthodontic tooth movement. Tooth movement is affected by factors such as: force magnitude; individual and tooth variation; intermittent or continuous forces and different types of tooth movement. Additionally, Quinn and Yoshikawa believed that tooth movement increases with stress up to a point after which additional increases create no movement. But this was challenged by Maltha, who stated that the movement can also decrease. The above factors, in addition to the four main reasons discussed above show that there is no ideal rate and force of orthodontic tooth movement. REFERENCES Andreasen, G., Johnson, P. (1967). Experimental findings on tooth movements under two conditions of applied force. The Angle orthodontist, 37(1), 9-12. Retrieved from: http://www.angle.org/doi/pdf/10.1043/0003 3219(1967)037%3C0009:EFOTMU%3E2.0.CO%3B2 Burstone, C. J. (1962). The biomechanics of tooth movement. Vistas in orthodontics, Lea Febiger, Philadelphia, 197-213. Farrar, J. N. (1888). A Treatise on the Irregularities of the Teeth and Their Correction:Including, with the Authors Practice, Other Current Methods (Vol. 1). De Vinne Press. Hixon, E. H., Aasen, T. O., Arango, J., Clark, R. A., Klosterman, R., Miller, S. S., Odom, W. M. (1970). On force and tooth movement.American Journal of Orthodontics,57(5), 476-489. doi:10.1016/0002-9416(70)90166-1 Krishnan, V., Davidovitch, Z. E. (2006). Cellular, molecular, and tissue-level reactions to orthodontic force. American Journal of Orthodontics and Dentofacial Orthopedics, 129(4), 469-e1. doi: 10.1016/j.ajodo.2005.10.007 Lee, B. W. (1965). Relationship between tooth-movement rate and estimated pressureapplied. Journal of dental research, 44(5), 1053-1053. doi: 10.1177/00220345650440051001 Lundgren, D., Owman-Moll, P., Kurol, J. (1996). Early tooth movement pattern afterapplication of acontrolled continuous orthodontic force. A human experimental model. American journal of orthodontics and dentofacial orthopedics, 110(3), 287 295. doi: 10.1016/S0889-5406(96)80013-8 Mayne, R. (2014).DEN2CGD,Lecture 11, Topic 2, Physiology of orthodontic tooth movement [Point slides]. DEN2CGD, Bendigo, Australia: La Trobe University, Department of Health Sciences. Oates, J. C., Moore, R. N., Caputo, A. A. (1978). Pulsating forces in orthodontic treatment. American journal of orthodontics, 74(5), 577-586. doi: 10.1016/0002-9416(78)90033 Owman-Moll, P., Kurol, J., Lundgren, D. (1995). Continuous versus interruptedcontinuous orthodontic force related to early tooth movement and root resorption. The Angle Orthodontist, 65(6), 395-401. Retrieved from: http://www.angle.org/doi/pdf/10.1043/00033219(1995)065 F%3E2.0.CO%3B2 Owman-Moll, P., Kurol, J., Lundgren, D. (1996). The effects of a four-fold increasedorthodontic force magnitude on tooth movement and root resorptions. An intra individual study in adolescents. The European Journal of Orthodontics, 18(3), 287 294. doi: 10.1093/ejo/18.3.287 Pilon, J. J., Kuijpers-Jagtman, A. M., Maltha, J. C. (1996). Magnitude of orthodonticforces and rate of bodily tooth movement. An experimental study. American Journal of Orthodontics and Dentofacial Orthopedics, 110(1), 16-23. doi: 10.1016/S0889 5406(96)70082-3 Proffit, W. R., Fields Jr, H. W., Sarver, D. M. (2013). Contemporary orthodontics. StLouis, Missouri: Mosby Quinn, R. S., Ken Yoshikawa, D. (1985). A reassessment of force magnitude inorthodontics. American journal of orthodontics, 88(3), 252-260. doi: 10.1016/S0002 9416(85)90220-9 Reitan, K. (1957). Some factors determining the evaluation of forces in orthodontics.American Journal of Orthodontics, 43(1), 32-45. doi 10.1016/0002-9416(57)90114-8 Ren, Y., Maltha, J. C., Kuijpers-Jagtman, A. M. (2003). Optimum force magnitude fororthodontic tooth movement: a systematic literature review. The Angle orthodontist, 73(1), 86-92. Retrieved from: http://www.angle.org/doi/full/10.1043/0003 3219(2003)073%3C0086:OFMFOT%3E2.0.CO;2 Ren, Y., Maltha, J. C., Vant Hof, M. A., Kuijpers-Jagtman, A. M. (2004). Optimum force magnitude for orthodontic tooth movement: a mathematic model. American journal of orthodontics and dentofacial orthopedics, 125(1), 71-77. Doi 10.1016/j.ajodo.2003.02.005 Schwarz, A. M. (1932). Tissue changes incidental to orthodontic tooth movement.International Journal of Orthodontia, Oral Surgery and Radiography, 18(4), 331 352. doi: 10.1016/S00996963(32)80074-8 Storey, E. (1973). The nature of tooth movement. American journal of orthodontics, 63(3), 292-314. doi: 10.1016/0002-9416(73)90353-9 Storey, E., Smith, R. (1952). Force in orthodontics and its relation to tooth movement. Aust Dent,56(1), 11-8. Wise, G. E., King, G. J. (2008). Mechanisms of tooth eruption and orthodontic toothmovement. Journal of dental research, 87(5), 414-434. doi:10.1177/154405910808700509

Effect of supply and demand and gas in our lifetime Essay

Oil has been an integral socio-economic vehicle which within the corporate scene remains a highly competitive socio-economic driver. Due to vast uses and demand, oil has become controversial and elastic in socio-politics. Here we see it causing socio constraints in oil producing countries and collapsing political institutions. Socially oil has a significant contribution in our general lifestyle. It has a comparative role within the context of mobility and industrial function where it is used in factories as well as in institutions which use combustive machinery. It is a determinant of economic prowess of a country. It plays a major role in research and advancement of power generation and use of bio fuels to ease environmental pollution. Gas is valuable in our lives based on the fact that it eases the burden of power use in cooking and within many socio institutions especially within our families. Gas also has been highly competitive and still remains so with many countries seeking to sustain demand. Recently European countries grappled with Russian company Gazprom over supply of gas when the company threatened to cut supplies. This paper reflects on the major effects of oil and gas on our lives in various aspects of socio-economics and its profundity. This profundity establishes the oil and gas use and contribution to socio-economics and politics. This analytical review covers environmental, political and research contributions, so as to keep sustenance of the same at per with developments in the technological trends within our lives which drain energy resources and adversely effect socio-economic stability. Contribution to socio economics Economic growth is dependent on energy resources. Energy supply within the development perspectives of a nation deplete economic recession and create more apertures for industrial progression in the nation. The distribution of resources within this economic perspective contributes to social –economic growth due to the dissemination of the resources made and gained from the industrial progression. Socio-economic progress is what supports the constituents of the society, namely the family. Most families own vehicles, machinery and combustive equipment that require oil to run them. They own various oil consuming devices like generators which they use to get power and run their daily activities. This perspective of integrating resources based on oil based contribution and importance is indicative of the pivotal role oil plays in the economic progression of a nation and a community. On the negative aspect, oil has very diverse negative effects on social economic gains and has led to the disintegration of economic stability within the units of the society. Increase in oil prices leads to stifling of social economics due to constrained spending so as to meet the higher cost of fuel. This constraint forces individuals to over spend and increased prices of goods and services. The effect spreads within the society to the most unfortunate and stirs unrest due to the high prices. On the same aspect oil has been a very competitive socially owned natural resources which in as many countries has caused political divisions and social disintegration. Communities in developing nations have been embroiled in long civil wars like in Nigeria. Nations with superior industrial needs have sought after taking advantage of lesser nations to establish forced oil drilling concessions so as to have a monopoly in the production of oil and directly befit their economic needs while hurting that of the producing country. The performance of the portfolio might be measured by the effects of changes in energy costs and availability of energy on the economy. Another portfolio measure might be the effects of the mix of energy sources on the diversity and vulnerability of the supply. Generating Electric Power in the Pacific Northwest: Implications of Alternative Technologies Christopher G. Pernin, Mark A. Bernstein, Andrea Mejia, Howard Shih, Fred Rueter, Wilbur Steger 2002. p 15 Effect on Resources Drilling oil has led to dilapidation of natural resources like forested land, marine resources and agricultural land. The effect on these natural resources is basically destruction of their existence so as to create sufficient exploration and drilling acreage. To excavate gas or oil, exploration and seismic survey has to be conducted on very significant area of acreage which completely reduces this area to a wasteful land for many years. The long term effect is that, the existing resources and land itself becomes wasted and polluted due to activities involved to get the gas or oil out. However there are positive attributes that come along with oil and gas production. There creation of jobs on these areas benefits local and professionals who have relevant experience and knowledge on the activities related to drilling and producing oil and gas. Creation of infrastructure and connection to electricity grids become the positive effects on the resources which can be utilized within the region the drilling or production is on going. The resources, like agricultural activities directly benefit from these changes and developments. Existing coffee factories get a boost to revert from using diesel engines to electricity. Communities are connected to the electric grid and can access electricity. Industries come up and processing of natural resources become easier. Proved reserves are both drilled and un-drilled. The proved drilled reserves, in any pool, include oil estimated to be recoverable by the production systems now in operation, whether with or without fluid injection, and from the area actually drilled up on the spacing pattern in effect in that pool. The proved un-drilled reserves, in any pool, include reserves under un-drilled spacing units which are so close, and so related, to the drilled units that there is every reasonable probability that they will produce when drilled. Bruce C.  Netschert The Future Supply of Oil and Gas: A Study of the Availability of Crude Oil, Natural Gas, and Natural Gas Liquids in the United States in the Period through 1975: 1958. p 7 Development of alternative fuels Oil and gas have led to positive research on energy needs globally. Companies and researchers have been seeking best solutions to the waning supplies and deposits of gas and oil to curb the eminent collapse of the supply and demand. Discovery of coal mines, use of electric car and trains development of alternative oil are diverse developments all based on the oil and gas supply and demand agenda. According to arguments based on the global perspective on demand and supply of gas and oil, it is questionable and much worrisome ‘Are resources likely to be available during the next fifty years in the quantities necessary to satisfy projected demands without substantial increases in prices? If not, what price in- creases are likely to be necessary to close the gap between supply and demand, and what are the effects of those increases likely to be? Ronald G. Ridker & William D. Watson: To Choose a Future: Resource and Environmental Consequences of Alternative Growth Paths. 980. p 96. Negative effects of the demand and supply is mainly seen within the oil curtails and supply context. International oil curtails have a stranglehold on the oil and gas prices and the effect of alternative oils becomes less dynamic and progressive stifling efforts to stipulate best policies to use to achieve the required progress in alternatives is slow. Implementation of development of alternative oils and energy resources has been ongoing. Creation of biodegradable oils has resolved much of the fears that demand would become elastic. Environmental effects Global warming and environmental degradation consequences on the flora are as a result of a lot of oil and gas exploration activities. Secondly the use of oil and gas in industries and within the concepts of combustion has led to degradation of the environmental. Industrial effluent related to oil has destroyed the flora while gaseous emission like carbon emissions from vehicles and industrial machinery has destroyed the ozone layer resulting to global warming. There are literally no positive implications on the environment by oil and gas. However on the profound aspect of research advancing of technology to improve on the air and to maintain a level of complacency within the ozone layer has led to discovery and global use of green houses and introduction of policies which reflect on addressing how to stop global warming. Governmental and geo-political effects A lot of the current crisis within the global fronts is based on escalation of demand of oil and gas by major world like the United States. The demand for energy, especially based on oil supplies has become un-foreseeable, as such the need to have vast reserves of oil within proximity as insulation to the critical point of demand and elasticity of demand is important. Non-Marxist social science, needless to say, had to contend with the reality, where incidents of collective violence were taking place all around. Facing this contradiction between their theory and reality, a compromise was reached by which it was hypothesized that anti-systemic conflict was only a temporary situation. This situation, they argued, would be symptomatic of the Third World nations going through a structural change. Structural change caused by the introduction of â€Å"economic development† and a new production relationship calls for the end to the traditional social and economic relationship. Dipak K. Gupta: The Economics of Political Violence: The Effect of Political Instability on Economic Growth. 1990 p 31 The issue here is that political prowess has influenced a lot of political inclinations in various nations within the world. On the same context, government policies to curb oil prices and to have reserves for future use have become null and wavering. The community within these jurisdictions suffer fluctuating oil prices and there is no consistency in the pricing hence the problem of constantly adjusting to the new prices due to lack of legislation. Political problems have emanated from this point with extremist policies on invasion of natural resources and barrel prices becoming tools of stifling economic progress in the communities.

Educational Reforms in Pakistan Essay

Educational reforms are a significant reference point in the educational history of Pakistan in terms of their scale, the amount of money invested in them, the order of their urgency and their official/political ownership. The reforms are also important as their need was felt by the donor country (the US), and the contours of the implementation process were drawn up by consultants who came as part of the grant package. Before we look at the politics of these educational reforms we need to understand that historically dominant groups have always used terms like ‘reforms’, ‘development’, ‘civilisation’, ‘emancipation’, and ‘peace’ for their hegemonic purpose. Many imperialist powers annexed other countries ostensibly to civilise them, to develop them, to liberate their people, and to bring peace to the colonies. The important point to note here is that hegemonic powers first turn development into ‘undevelopment’ and then offer reforms for their own version of development. For instance, when the British came to India the country was doing fine economically. Michael Parenti in Against Empire writes, â€Å"In 1810, India was exporting more textiles to England than England was exporting to India. By 1830, the trade flow was reversed. The British had put up prohibitive tariff barriers to shut out Indian finished goods and were dumping their commodities in India, a practice backed by British gunboats and military force. Within a matter of years, the great textile centres of Dacca and Madras were turned into ghost towns.† This rather long quote refers to a typical pattern of hegemonic designs of development, ‘undevelopment’ and one’s own version of development. In India, after turning development into ‘undevelopment’, the British claimed to bring development through the construction of roads, railway tracks, buildings etc. This view of development is purely physical. This interesting pattern is also shared by military governments. It is claimed that most developmental works were carried out by military dictators like Ayub, Zia, and Musharraf. We can also equate this pattern with ‘form’, ‘deform’, and ‘reform’. Military governments first dissolve parliament and then, after ruling for a long time, promise to give back democracy (their own version of it) as a token of favour. In other words, the dominant group first deforms the existing practice and then embarks on reforming the process. Let us now look at the rationale of the post-9/11 reforms. Ironically the need for such reforms was not felt by the local government but by the US. In the 9/11 Commission report, the US is urged to â€Å"support Pakistan’s government in its struggle against extremists with a comprehensive effort that extends from military aid to support for better education, so long as Pakistan’s leaders remain willing to make difficult choices of their own.† Following this commitment, a large sum of money was given to Pakistan for educational reforms. According to USAID, â€Å"From 2002 through 2006, USAID provided a total of $449m to address the most pressing needs: education, health, economic growth, and good governance.† One of the major reforms was to purge the curriculum of hate material. It is important to note that most of this hate material was in fact included during the period of the Afghan war. Besides help in the shape of weapons, money, training etc, a large sum of money was also allocated by the superpower for designing such primers and books that would excite the youth for jihad. This jihad was a political need of the superpower to settle scores with the Soviet Union. For this purpose a centre was established in Peshawar to design such books. Tariq Ali (quoted in Mamdani) referred to primers that stated that the Urdu letter tay stood for tope (cannon), kaff for Kalashnikov, khay for khoon (blood) and jeem for jihad. It is interesting that money is now being squandered on taking out the hate material which was once inserted with consent. This should not come as a surprise as education has always been used by hegemonic forces as a potent tool to realise their vested interests by moulding marginalised groups. Having looked at the upper level of politics in educational reforms now let us see political manoeuvring at the national level. Pakistan has always suffered from the problem of poor allocation of funds for education. Here was a very good opportunity to make appropriate use of money to bring a qualitative change to the educational system of Pakistan. But on the contrary, the government used this money for its own image-building. To do wonders, a retired general was appointed as minister for education. At the local level, slogans of self-praise, such as ‘Parah Likha Punjab’ were coined to create the illusion of development. On the top, political appointments were made, some of them quite controversial. A sizeable amount of funds was allocated to print and electronic advertisements for the image-building of the provincial leadership. In the books published by the Punjab Text Board a message from the chief minister was also inserted. A typical practice in most research projects, initiated in the name of educational reforms, was to focus on the enhancement of numbers. Showing increased numbers at the end of a research project would satisfy the donors, and the salaries of the employees and consultants would be justified. What do we find as a result of such lucrative projects? We should expect a typical number-crunching game without any sustainable qualitative change. It is important to realise that for real improvement in education, money is important. But money alone cannot bring about any meaningful change unless the desire for reform comes from within, appointments are made on the basis of pure merit, planning is done carefully, an effective monitoring system is in place and goals are not limited to demonstrating expansion in numbers.

Fermentation vs. Anaerobic Respiration

All living things must have constant sources of energy to continue performing even the most basic life functions.  Whether that energy comes straight from the sun through photosynthesis or through eating plants or animals, the energy must be consumed and then changed into a usable form such as adenosine triphosphate (ATP). Many mechanisms can convert the original energy source into ATP.  The most efficient way is through aerobic respiration, which requires oxygen. This method gives the most ATP per energy input.  However, if oxygen isnt available, the organism must still convert the energy using other means.  Such processes that happen without oxygen are called anaerobic.  Fermentation is a common way for living things to make ATP without oxygen.  Does this make fermentation the same thing as anaerobic respiration? The short answer is no.  Even though they have similar parts and neither uses oxygen, there are differences between fermentation and anaerobic respiration.  In fact, anaerobic respiration is much more like aerobic respiration than it is like fermentation. Fermentation Most science classes discuss fermentation only as an alternative to aerobic respiration.  Aerobic respiration begins with a process called glycolysis,  in which a carbohydrate such as glucose is broken down and, after losing some electrons, forms a molecule called pyruvate.  If theres a sufficient supply of oxygen, or sometimes other types of electron acceptors, the pyruvate moves to the next part of aerobic respiration.  The process of glycolysis makes a net gain of 2 ATP. Fermentation is essentially the same process.  The carbohydrate is broken down, but instead of making pyruvate, the final product is a different molecule depending on the type of fermentation.  Fermentation is most often triggered by a lack of sufficient amounts of oxygen to continue running the aerobic respiration chain.  Humans undergo lactic acid fermentation. Instead of finishing with pyruvate, lactic acid is created.  Distance runners are familiar with lactic acid, which can build up in the muscles and cause cramping. Other organisms can undergo alcoholic fermentation, where the result is neither pyruvate nor lactic acid.  In this case, the organism makes ethyl alcohol.  Other types of fermentation are less common, but all yield different products depending on the organism undergoing fermentation. Since fermentation doesnt use the electron transport chain, it isnt considered a type of respiration. Anaerobic Respiration Even though fermentation happens without oxygen, it isnt the same as anaerobic respiration.  Anaerobic respiration begins the same way as aerobic respiration and fermentation.  The first step is still glycolysis, and it still creates 2 ATP from one carbohydrate molecule.  However, instead of ending with glycolysis, as fermentation does, anaerobic respiration creates pyruvate and then continues on the same path as aerobic respiration. After making a molecule called acetyl coenzyme A, it continues to the citric acid cycle.  More electron carriers are made and then everything ends up at the electron transport chain.  The electron carriers deposit the electrons at the beginning of the chain and then, through a process called chemiosmosis, produce many ATP.  For the electron transport chain to continue working, there must be a final electron acceptor.  If that acceptor is oxygen, the process is considered aerobic respiration.  However, some types of organisms, including many types of bacteria and other microorganisms, can use different final electron acceptors.  These include nitrate ions, sulfate ions, or even carbon dioxide.   Scientists believe that fermentation and anaerobic respiration are older processes than aerobic respiration.  Lack of oxygen in the early Earths atmosphere made aerobic respiration impossible.  Through evolution, eukaryotes acquired the ability to use the oxygen waste from photosynthesis to create aerobic respiration.