Overview of Critical Thinking Skills (CTS)

What is Critical Thinking (CT)?

Many researchers including Facione, Simpson and Courtneay, Banning, Brookfield, Ornstein and Hunkins, Sternberg, Ennis and Lipman have defined critical thinking.12-20 Researchers debate whether critical thinking can be learned, or is a developmental process, regulated by motivations, dispositions, and personality traits.  Despite differences of opinion, many researchers agree that critical thinking is: “Purposeful, self-regulatory judgment which results in interpretation, analysis,evaluation, and inference, as well as explanation of the evidential, conceptual,  methodological, criteriological or contextual considerations upon which judgment is based’.12

Critical thinking is also regarded as intellectually engaged, skillful and responsible thinking that facilitates good judgment because it requires the application of assumptions, knowledge, competence and the ability to challenge one’s own thinking. Critical thinking requires the use self-correction and monitoring to judge the reasonableness of thinking as well as reflexivity. When using critical thinking, individuals step back and reflect on the quality of that thinking. Simpson and Courtneay pointed out that critical thinking processes require active argumentation, initiative, reasoning, envisioning and analyzing complex alternatives and making contingency-related value judgments.13

According to Banning, critical thinking involves scrutinizing, differentiating and appraising information as well as reflecting on information to make judgments that will inform clinical decisions.14 Brookfield asserted that identifying and challenging assumptions and analyzing assumptions for validity are essential to critical thinking skills. He also suggested that because critical thinkers possess curiosity and skepticism, that they are more likely to be motivated to provide solutions that resolve contradictions.15

Others such as Ornstein and Hunkins suggest that critical thinking and thinking skills refer to problem-solving and related behaviors.16 For a number of years, dental educators thought that teaching problem-solving skills was akin to teaching critical skills. While teaching problem-solving skills is important to the process of learning how to use critical thinking skills, in the absence of other types of learning activities, it may not be enough.

Sternberg, Ennis, and Lipman asserted that critical thinking skills are not a fixed entity but are form of intelligence that can be taught.17 The ability to develop critical thinking skills may be likened to Piaget’s concrete and formal operations. If students have not reached the formal operations stage then their ability to use critical thinking skills may be limited by an inability to handle abstract ideas. It is important to remember that Piaget’s stages of cognitive development are also linked to intellectual potential and environmental experiences. If the learning environment is crucial to the development of critical thinking skills, what instructional strategies can be used to promote critical thinking?

Sternberg asserts that critical thinking involves complex mental operations that cannot be broken into discrete styles of thinking. He claims that CT involves students’ total intellectual functioning, not a narrowly defined set of skills.18 He postulates that there are three mental processes that foster critical thinking: meta-components, performance components, and knowledge-acquisition strategies.18 Meta-components refer to higher order mental processes that individuals use to plan, monitor, and evaluate what they do. Performance components refer to the actual steps taken or strategies used, while knowledge-acquisition strategies refer to the ways in which individuals relate old to new material and apply new material.18 Sternberg does not specify a “how” approach to teaching and learning critical thinking skills.  Instead, he provides general guidelines for developing or selecting a program or curriculum that will foster CTS. Interestingly, however, not surprisingly, Sternberg points out that the ways in which students are taught during their formative years does not adequately prepare them for the kinds of problems and critical thinking skills tasks that they will face in everyday life.17 Tasks that stress right answers or truth telling or use objectively scored tests are generally removed from real world relevance. Thus, it is particularly important that all aspects of dental educational curriculum stress real world practice, the importance of oral health care, and the relationship of overall oral health care to systemic health by teaching students how to use critical thinking skills.

Lipman, like Sternberg, does not specify a “how to’ approach, however, he makes clear distinctions between ordinary thinking and critical thinking. He explains that ordinary thinking is simplistic thinking because it does not rely upon the use of standards or criteria. Examples of ordinary thinking are guessing, believing, and supposing. Lipman describes critical thinking as a complex process that is based on standards of objectivity, utility or consistency, in which students can reflect upon the certainty of their thinking, because critical thinking is self-correcting.19 In order words, students can defend their thinking with evidence.  Ennis asserts that to help students develop critical thinking skills, teachers must understand the cognitive processes that constitute critical thinking and use instructional activities that will develop these processes. He recommends that instructors teach students how to define and clarify information, ask appropriate questions to clarify or challenge statements or beliefs, judge the credibility of sources, and solve problems by predicting probable outcomes logically or deducing.20 Ennis also suggests that critical thinkers also demonstrate particular attributes. Critical thinkers tend to:

(1) be capable of taking a position or changing a position as evidence dictates;

(2) remain relevant to the point;

(3) seek information as well as precision in information;

(4) be open minded;

(5) take into account the entire situation;

(6) keep the original problem in mind;

(7) search for reasons;

(8) deal with the components of a complex problem in an orderly manner;

(9) seek a clear statement of the problem;

(10) look for options;

(11) exhibit sensitivity to others’ feelings and depth of knowledge, an

(12) use credible sources. 20

Critical thinkers use these skills appropriately and usually without prompting. They are generally predisposed to think critically and to evaluate the outcome of their thought processes.21

Instructional Strategies and Critical Thinking

Researchers have asserted that how educators teach has a direct influence on what is learned.22 Thus, the instructional strategies selected must be appropriate to the outcomes that are sought. For example, strategies of inquiry are contingent upon the problem being investigated and the targeted concepts, so it is essential that they be integrated with the associated processes of inquiry in order for students to see how new knowledge evolves.23 Researchers have also recommended eliminating superfluous activities, repetitious content, and expanding learner-centered active forms of experiences to promote critical thinking skills.24 If the goal is for students to use critical thinking skills, then opportunities to: a) engage in problem-based learning, b) analyze case-based scenarios, and c) engage in debates, role-play, argument mapping, think aloud, and simulation among others, should constitute the majority of learning activities.23 The benefit of engaging students in critical thinking skills learning experiences is the public nature of their thinking. When students engage in CTS, they have an opportunity to examine tacitly held knowledge of one another, make knowledge and thinking explicit, respond to questions and comments, and clarify their thinking processes.25

Several researchers have pointed out the type of instructional strategies that may be used to promote students’ critical thinking skills. For example Weerts suggested that working in groups might reduce students’ stress while trying to answer difficult questions. In fact, she points out that working together may result in better answers than working alone.26 Many dental educators might eschew the notion of using groups, however, it is important to point out that even in classes of 80-100 dental students, groups of 6-8 students could be developed to facilitate learning and inquiry. These same groups could be responsible for answering questions about chapter readings and called upon randomly during class time. For example, instructors can consider writing 3-4 focus questions that accompany the readings to guide student comprehension. Instructors can also tell the students that they should to be able to answer those questions in class. In this way, students can be held responsible for learning some of this discrete information before class. Rather than having the instructor feel responsible for “telling” students what they should know, they can elicit the key concepts from students. Class time can then be used to present a case where the concept is illustrated and students can work groups to analyze how that concept is operationalized rather than delivering discrete knowledge via lecture. Weerts also suggests that student groups can work together and develop critical thinking skills by:

  • identifying issues
  • gathering authoritative sources
  • identifying potential treatments
  • presenting competing points of view
  • weighing modalities in light of the presenting case and then agreeing upon the treatment plan. 26

To ensure that students are developing appropriate skills the instructor and students can use a Likert scale to rate each other on the following criteria: (1) accuracy and relevancy of supporting evidence, (2) credibility of authoritative knowledge, (3) depth and breadth of thought and (4) clarity and soundness of responses. Hendricson et al. suggest several active learning strategies that can be used to develop students’ critical thinking skills (See Table 2).

Table 2. Strategies to Enhance Critical Thinking Skills

  • Use questions that require students to analyze problem etiology, compare alternative treatment modalities, provide rationales for plans of action and predict outcomes.
  • Critique cases and review decisions to identify excellent practices and to identify errors.
  • Write assignments that require students to analyze problem etiology, compare alternative treatment modalities, provide rationales for plans of action and predict outcomes.
  • Analyze work products and compare how outcomes compare to best practices and compare student reasoning about problems to those of an expert panel.27

Van Gelder concurs with Hendricson et al. that critical thinking must be deliberately practiced with the intent to improve performance, however, he points that CT is hard and that human beings are not naturally critical.28 Shermer29 agrees and describes human beings as “pattern-seeking story telling animals … [who] like things to make sense, and the kinds of sense we grasp most easily are simple familiar patterns or narratives” (p. 42).28 This penchant for the familiar has implications for the curriculum. As a type of thinking that eschews the uncritical acceptance of information, critical thinking should be a deliberate part of the curriculum. Moreover, exposing students to good examples is insufficient to developing critical thinking skills. Students must demonstrate the ability to transfer critical thinking skills from one situation to another. As Kuhn points:

The best approach … may be to work from both ends at once-from a bottom-up   anchoring in the regular practice [of what is being taught] so that skills are          exercised, strengthened and consolidated as well as from a top-down fostering of    understanding and intellectual values that play a major role in whether these skills     will be used (p. 24).30

Kuhn’s point has implications for teaching critical thinking skills in the basic science courses as well. Even though students are heavily immersed in learning a tremendous amount of information, they still should be presented with critical thinking learning experiences that embed concepts in actual practice-based scenarios.30

Van Gelder suggests that students’ critical thinking skills improve faster when instruction is based upon argument mapping. He asserts that when arguments are presented in diagrammatic form, students are more capable of following critical thinking procedures.28 Because argument maps are visual and more transparent, they make the core operations of critical thinking more straightforward. van Gelder cautions, however, that belief preservation is human tendency. He states that individuals tend to make evident secondary to beliefs. 28  Thus, critical thinking runs counter to human tendencies. Humans tend to seek evidence that supports beliefs or ignores evidence that goes against those beliefs. Ideally, critical thinkers recognize this and will put extra effort into searching for evidence that contradicts their own beliefs and cultivate a willingness to change when evidence to the contrary begins to mount. 28

To apply argument mapping to clinical reasoning consider Case #1.

Case #1 Differing Views on Patient Treatment

A 60-year old woman presents with internal resorption of the left maxillary lateral incisor. Radiographic exams reveal that saving the tooth is questionable. The student dentist recommends to Professor Marlin the patient receive a fixed partial denture (FPD). Professor Marlin confers with Professor James and James recommends a removal partial denture (RPD).

Case #1 Questions

  1. The students are instructed to use argument mapping to explain the phenomenon.
  2. Next, students are asked to write about the contradictions that differentiate viewpoints about FPD and RPD and to write about the counter-arguments.
  3. Finally students are to identify their treatment decisions to provide evidence that supports or justifies their assertions.

Lee and Ryan Wenger recommend the use of the “think aloud” seminar as a teaching tool.31 Using this approach students are presented with a case and are asked relevant questions regarding symptoms and presenting signs. Using this approach, students can exclude underlying pathologies based upon the presentation. This process of excluding potential diagnoses aids students’ critical thinking by encouraging them to openly verbalize the rationales behind their opinions.31

Wong and Chung used simulation to develop diagnostic reasoning skills among nursing students. 32 Students were asked to consider the etiological factors, presenting symptoms and clinical signs of a patient who presented with a particular condition.  As they examined the underlying patholophysiology, the CTS they developed were: “assessing duration” and “frequency of symptoms and additional triggers.” They also were expected to review their understanding of the possible pathophysiological significance. The next set of CTS they focused on was: “considering the pros and cons of treatments,” “drug actions and the possible side affects on the patient.” Finally they explored the efficacy of the outcomes. CTS developed in this phase were: determining the success of the treatment, or complications, considering the time it took to resolve the clinical signs and symptoms or considering reasons for the development of symptoms.32

Other strategies that can promote critical thinking include using particular behaviors and asking questions (See Table 3).

Table 3. Strategies that Promote Critical Thinking

  • Reflecting on the use of critical thinking
  • Creating a climate of inquiry
  • Making the teaching of thinking explicit
  • Rewarding good critical thinking and challenging poor critical thinking
  • Providing diverse problem contexts that are likely to engage students in critical thinking are essential.33

Asking particular types of questions (shown below) also promotes critical thinking (See Table 4).

Table 4. Questions that Promote Critical Thinking

  • What other treatment options have you considered? Why have you chosen this approach?
  • Can you give me more details?
  • Can you provide some evidence that supports your recommendation?
  • How could we check that?
  • Is there another way to look at this problem?

Also, Facione and Facione (1996) recommend that students learn to think about their own thinking. For example, “If you were teaching a colleague about this situation, how would you lead him or her through the issues” (p. 51)?34

Logical Fallacies

While faculty strive to develop students’ abilities to use critical thinking, it is also, important to communicate the logical fallacies that students may demonstrate in their writing or while speaking. Engel provides an overview that illustrates the common fallacies.35 An adapted version of three types of fallacies: ambiguity, presumption, and relevance are shown in Table 5.

Table 5. Common Logical Fallacies (Adapted from Engel, 1990)


Types of Fallacies                                                      Examples

Fallacies of ambiguity – Unsound arguments because the words used can be understood in more than one sense.
  • Poor sentence structure
  • Use of abstract words that endow human attributes (e.g., “the organization made people…”
  • Use the same word to mean different things throughout, (e.g., using man to mean humankind and later to mean man as opposed to woman)


Fallacies of presumption – Unsound arguments because of unproven assumptions, overlooking, and evading or distorting facts.
  • Use of sweeping generalizations
  • Premature closure (using insufficient evidence or an isolated example to make generalizations)
  • Begging the question (when a conclusion restated the premise using different words
  • Applying classifications as either/or and ignoring other existing alternatives


Fallacies of relevance –Use of irrelevant premises or attempts to obscure issues by stirring up emotions.
  • Appeal to pity (trying to arouse pity rather than present evidence)
  • Appeal to ignorance (trying to prove a claim by focusing on the lack of evidence against it)
  • Appeal to fear (trying to persuade by using fear)
  • Appeal to authority (trying to persuade by citing authorities, opinion, and tradition, rather than citing evidence)
  • Ad hominem (avoiding discussion of the issues by describing attributes of the people involved rather than the issue at hand).

Allowing Time for Reflection

Teaching students how to use critical thinking skills shifts teaching from a model that largely ignores thinking to an approach that renders it pervasive.36 When content is didactically taught, it is treated as static and students are unlikely to think it through. They tend to rely on rote memorization, without grasping the logic, supporting evidence and application of what they are trying to memorize. Students, who learn through a critical thinking process, truly learn content. At every level, students need to learn how to:

Ask questions precisely, define contexts and purposes, pursue relevant information, analyze key concepts, derive sound inferences, generate good reasons, recognize questionable assumptions, trace important implications, and think empathetically within different points of view (p. 20).36

Critical thinking is difficult and requires overt practice using a variety of learning activities across the dental curriculum. It is also important to recognize the role that reflection plays in its development. Students need time to think about what they are learning and reflect. However, what they are learning must have an impact on their feelings in order for critical thinking to occur.

Emotions and Critical Thinking

The role of emotion in learning how to use critical thinking skills is yet, another area that necessitates research inquiry. As Zull points out, if we want students to retain concepts then we must allow them to put things into their words – verbally and in writing.37 If we stop and provide wait time, this gives students time to think before speaking and put things into their own words. Processing information takes time, stating things correctly also takes time. If students cannot do this alone, we can give them the opportunity to discuss questions with others. Further, giving students time to reflect, is giving them time to make connections.

Zull explains that first the sensory cortex receives sensory input or concrete experiences. Next, the back integrative cortex tries to create meaning and images, the human process of reflection. The frontal integrative cortex is responsible for short-term memory and problem solving, making decisions and language, making judgments and evaluations. 37 This activity is akin to the how learners handle abstractions – manipulating images and language to create new mental arrangements. The motor cortex triggers all coordinated and voluntary muscle contractions. This matches with the action that completes the learning cycle – actively testing abstractions and converting ideas into physical actions. 37 The brain visualizes things in little bits and all information arrives at the same time to produce an outline of objects and features in the visual field. 37 Thus, the brain can fully see great detail and nuance. Converting ideas into images helps students learning. Images enhance recall and aid in discovery. Sometimes the best teaching is just showing student how. To ensure that students learn, we need to limit the amount of information that we give them. This means we should break up information or limit the amount that we want them to process to three or four pieces.

The amygdala is responsible for screening experiences. 6 If something is recognized as dangerous, instinctively the body will jump back or freeze. When students first encounter something new they may have a somewhat negative reaction. The instructor needs to find a way for the student to move into a more positive emotional territory. 37 Making suggestions or showing examples can remind the student what he or she already knows and then the student can hang newly acquired knowledge on the “scaffolding.” The support given by the instructor allows the student some success, no matter how big or small. Realizing success, the student’s emotions turn more positive and then he or she feels more hope, interest and curiosity. At this point, the student is able to assume more control of the learning process. Boyd (2002) concurs and states, “emotions … constantly regulate what we experience as reality” (p .717).38 She points out that, “The limbic system plays an important role in processing emotion and memory and therefore appears to be important in the transfer of short-term memory into long-term memory” (p. 717). 38 The implications of this research are that engaging students emotionally and actively strengthens memory.

Teaching Students to use CTS during Instruction

There is some empirical evidence that a four-year undergraduate experience contributes to modest gains in overall CT. However there is little scientific evidence that a single course, other than a critical thinking skills course makes a positive measurable difference. 40 Even in the latter case the evidence is mixed.41 However, recent studies show that limited efforts to infuse critical thinking in instruction can lead to improved scores on the Cornell Z test. 40 Allegrettti and Frederick (1995) reported pre to posttest gains on the Cornell Z test for a group of college seniors (n = 24) who took a capstone integrated psychology and philosophy course. 42  Solon (2001) found that a partial treatment group of psychology students (n = 26) improved their CT scores on the Cornell Test when compared to a group of untreated humanities students (n= 26).43 The results were significant beyond .001. In 2003, Solon studied three groups to compare coursework effects and reported that the full treatment group (n = 25) significantly outscores both the partial (n= 25) and non-treatment (n= 25) groups on the Cornell Z test.43 Solon (2007) reported that a group of introductory psychology students (n= 25) received a moderate infusion of critical thinking (10 hours instruction and 20 hours of homework).44 When compared to no-treatment group (n= 26), the experimental group improved their CT scores significantly as measured by the Cornell Z test.44 These findings suggest that even a moderate infusion of critical thinking skills instruction can result in enhanced reasoning skills without requiring a significant investment from the instructor. 40 Collins and Onwuegbuzie reported significant relationships between overall CTS and achievement in graduate level research methodology course at the midterm (r= .34, p <.01) and final (r= .26, p <.01) stages.45 Onwuegbuzie compared the CTS of master’s and doctoral level students. He reported that doctoral level students (n = 19) obtained statistically higher overall CTS using the California Critical Thinking Skills Test than the masters’ degree students (n = 101), (t= -3.54, p  <. 01).46 The effect size (d = 0.92) associated with this difference was extremely large. 46

Teaching CTS requires instruction that uses higher order taxonomic skills. These skills require student demonstration or teacher usage of behaviors classified as analysis, evaluation and creation (levels 4, 5, and 6 on Bloom’s revised taxonomy). When teaching takes place at higher levels of learning, lower order behaviors such as remembering, understanding and applying are subsumed within instruction. The table below lists the type of behaviors that are common at each level of learning and examples of related dental education activities (See Table 6).

Table 6. Revised Bloom’s Taxonomy, Sample Verbs and Related Learning Activities47*

Taxonomic Levels                  Sample Verbs                                  Dental Learning Activity                   

Level 6 -Creating

Synthesize, organize, deduce, plan, present, arrange, blend, create, devise, rearrange, rewrite

A prosthodontics patient, aged 62 has twp fixed mandible bridges that have deteriorated over the last two years due to poor hygiene control. These bridges now need replacement. You are a recent dental graduate in a practice with two senior partners. The senior dentists suggest taking impressions and replacing the bridges. You have read the recent literature on dental implants and want to offer the patient this option, however, the senior partners are not familiar with the  state of the art information about implants. You recognize that implants are more appropriate to the patient’s needs and that over time represent a cost savings to him. Develop a plan for responding to the senior partners, in which you provide an evidence-based rationale for suggesting the use of dental implants.

Level 5- Evaluating

Critique, defend, interpret, judge, measure, test, select, argue, award, verify

Two patients ages 18 months and 10 years old have cleft palate. Neither patient has been previously seen by a healthcare professional or treated for this condition up until now. Students are given a complete survey of the dental, medical and psych-social history of each patient and are asked to develop a treatment plan using authoritative and credible sources.

Level 4 – Analyzing

Determine, discriminate, form, generalize, categorize, illustrate, select, survey, take apart, transform, classify

A 32 year old white male arrives at your office and presents with pain and swelling over the “upper right” canine tooth for the past three days. His medical history is remarkable for GERD for which he takes Prilosec daily. Also he is allergic to Pencillin (rash develops over his torso and gets a fever after taking Augmentin). Your exam reveals intraoral and extraoral swelling over tooth #6. A radiogrtaph reveals radiolucency with caries under the crestal bone, which is non restorable. What are your  concerns? How would you treat and prescribe?

Level 3 – Applying

Convert, demonstrate, differentiate between, examine, experiment, prepare, produce, record, discover, discuss, explain

After completing textbook readings on the basics of periodontology, students are asked to explain, using images and in lay terms, the pathogenesis of periodontal disease to your patient.

Level 2- Understanding

Differentiate, fill in, find, group, outline, predict, represent, trace, compare, demonstrate, describe

In an introductory endodontics course, students are given a quiz on isolation. For question #1, they are asked to state five reasons that a rubber dam isolation is essential during endodontic procedures.

Level 1 – Remembering

Define, distinguish, draw, find, match, read, record, acquire label, list


From a list of 10 options, students are asked to match five that are associated with a periodontic pocket.



Making Critical Thinking Explicit

Teaching for critical thinking is a rational and intentional act. Typically, instructors cannot suddenly decide to teach CTS and develop an appropriate learning activity. Each instructor must have clear understanding of what CTS is, what it looks like during instruction, and what strategies should be used during particular classroom and pre-doctoral clinical learning activities. Thus, developing a repertoire of well-honed CTS activities that are appropriate to your specific discipline are advisable.

Also crucial to the teaching of CTS, is telling students that you will teach CTS, how you intend to do so, and what will be required of them as learners. Having an explicit conversation with students about what CTS is, what it looks like, and how you will model it, is important so that students can differentiate the teaching of CTS from learning that emphasizes lower level learning. Effective teaching of university-aged students is characterized by collegial and collaborative processes, not instruction that is ambiguous, whereby the learner does not know what to expect next, or have a clear understanding of what type of behavioral or skill changes they should demonstrate as a result of the teacher-student interaction. Teaching explicitly helps ensure that less re-teaching will be needed because both teachers and students know their responsibilities as instructors and learners.

Stages of Critical Thinking

Paul and Elder claim that individuals progress through predictable stages of unreflective, challenged, beginning, practicing, advanced, and master thinking. 48They point out that unless educators help students develop an intellectual vocabulary for talking about thinking and are challenged to identify the problems in their thinking, their own cognitive processes will remain invisible to them. The implications for curriculum development are that if instructors want students to develop critical thinking skills, then critical thinking must be integrated into instruction at the foundational level.

It is also important to recognize that when patient care is task focused it can obscure the bigger picture and become a barrier to the development of critical thinking skills. Individual personality, background and position might also limit one’s ability to think critically. Additionally, gender, age, religion, and socio-economic status might influence the development of critical thinking skills. One of the biggest barriers to the development of CTS is our educational system. Although it is important to recognize these attributes as potential barriers, it is more important that dental educators establish the kind of learning environments that will foster the development of CTS.

Case #2 Why are Mrs. Connor’s Teeth Yellow?

Mrs. Connor, a 74-year old white female comes to your office as a new patient. She presents with a complaint that her teeth have become yellow and unattractive. Her husband died a year ago and since then she has been drinking 8-10 cups of coffee daily. Her internist diagnosed her with anemia and high blood cholesterol. She is taking iron and Liptor. She feels better since she began taking Liptor but feels that her teeth are too yellow. She recently met a widower who invited her to dinner next week. She is worried about the appearance of her teeth.

Case #2 Questions

  1. While working in groups of six, students are to write at least 4 hypotheses about why Mrs. Connor’s teeth are yellow.
  2. Students also must determine if white teeth are important to the health and wellbeing of geriatric patients.
  3. Is there a relationship between the need of care and the use of dental services by older patients?
  4. The student group must outline their recommendations and a rationale for the treatment plan that will be presented to Mrs. Connor at her next dental appointment.

Teachers must recognize that not all students will move at the same rate as they develop such skills. Thus, the instructional methods and objectives need to match students’ cognitive and experiential abilities while trying to stretch students to their growing edge.49 Students’ capacity for self-directed learning (SDL) which is required to implement reflective judgment underlies many of the critical thinking skill dispositions.27 There is evidence that the students who use the “learn by doing approach” routinely to explore problems develop more sophisticated SDL than students in the lecture-based curricula. 49 The reflective thinking aspect of critical thinking is considered essential to clinical judgment.50 Tanner asserts that using the skills associated with reflective thinking prepares students for ill-structured or ambiguous problems that they are likely to encounter is clinical practice.51

Problem-based learning is a popular instructional strategy for promoting collaboration, reflection and negotiating different and individual constructions of knowledge.7 Some researchers assert that the best use of PBL is when problems are unsolvable or when they generate many individual constructions of knowledge that appear valid. 7 However, using only problem-based learning to teach critical thinking skills may not be enough. This instructional strategy does not necessarily equip students with the ability to analyze or critique a given situation or the information with which they are been provided. A variety of instructional strategies that give students the opportunity to think aloud, role play, prioritize alternatives, communicate conclusions effectively, simulate, or defend the logical basis of their thinking is recommended to foster students ability to use critical thinking.

Asking students to apply their understanding of dental/medical knowledge to treatment planning and diagnosis is not an example of CTS. However, asking students to determine differential diagnoses of caries and periodontal disease among patients at various stages of lung cancer will require the ability to reason and justify particular treatment plans, or demonstrate critical thinking skills. Habits of the students who demonstrate critical thinking as are follows: (a) making logical inferences, (b) offering opinions with reasons, (c) evaluating, (d) grasping principles, (e) classifying, (f) making criteria-based judgments, (g) making evidence-based decisions, and (h) reflexivity.

Case #3 Female with Erythroplakia

A 40-year old female, Mrs. Jacklin presents with a history of SLE and erythroplakia on the left lateral border of the tongue. She states that she is experiencing a burning sensation on her tongue. She asks the dentist why she is having this discomfort and what she can do to make the sore on her tongue go away. The oral exam shows that Mrs. Jacklin has poor oral hygiene and mild dry mouth (xerostomia) but is otherwise not significant for oral health concerns.

Case #3 Questions

  1. While working in groups of 4, students asked to locate the most four recent references on oral lesions.
  2. Using those resources, they are asked to write 5-6 reasons that the patient is experiencing tongue lesion and determine what questions they should ask the patient about her personal and social history.
  3. Next, they are to identify questions to ask her about her medical history.
  4. Using the information that they have acquired, they are asked to generate a list of potential treatment plans and the benefits and limitations of each plan.
  5. What should they tell the patient and why?

Critical thinking is not: (a) applying what you have learned in decisions making and treatment planning, (b) keeping students awake, interested and motivated, or (c) linear, or step by step thinking. Critical thinking cannot be taught in a learning environments in which the dental educator always lectures or tells students what ought to be undertaken during patient treatment, or shows students how to do a procedure correctly. Some of the habits of students who do not use critical thinking skills are: (a) disorganization (in thought processing, preparation and behaviors), (b) overly simplistic thinking  (“I had enough information, there was no need ask for additional information”), (c) use of unreasonable criteria (“If my belief is sincere, evidence to the contrary is irrelevant”) and (d) use of facts erratically (Looking only at the area of interest, he offered biased interpretations of the radiographs).

Critical thinking skills can be developed with frequent practice and the use of multiple types of ill-structured problems and situations that require the ability to recall useful knowledge quickly, use pattern recognition, discern pertinent information, think ahead, and anticipate outcomes and problems while remaining composed enough so that emotions do not hinder decision-making skills. However, it is important to recognize the CTS do not develop spontaneously or with maturation. Since strong personality components underlie CT dispositions, what happens if students admitted to colleges of dentistry do not already possess these traits?


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