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Anxiety prevention: Implementing the 4 S principle in conservative dentistry



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24 auxiliary September/October 2007
High levels of dental anxiety is a problem that
many dental patients experience. Most
recent studies in the international literature
show that the prevalence of severe dental anxiety is
approximately one in every 7 adults, and the same
rate was documented in Australian adults in a 2006
telephone interview survey.1Most studies also show
that females in the middle adult years have the
highest prevalence, which also is true in Australia.
Known effects of dental anxiety are many (Table 1)
and impact upon the dental practice as well as upon
the individual patient. Altered patterns of care are
perhaps the most obvious impact of dental anxiety
with disease having progressed to a stage too late
for conservative measures to be effective. A
surprising statistic from 2006 is that only 25% of
visits in private general practice in Australia were
for recall or maintenance - the same percentage as
for treatment of dental caries as the presenting
problem!2This figure was not greatly different from
the Brisbane Statistical District Survey of Adult
Dental Health conducted in 1984,3in which the
author participated as a field clinical examiner.
Clearly, dental anxiety has not altered significantly
over the quarter century period.
Severe dental anxiety is a multifaceted problem
with no one common single causal factor in all
patients (Table 2), although for most patients the
stimuli for dental fear are sensory in nature. By
focussing on these stimuli, the clinician aims to
reduce the anxiety response at its sources, as
opposed to dulling the response pharmacologically
or by using distraction methods. The 4 S principle
is based on removing four of the major sensory
triggers for dental anxiety, and it is used in con-
junction with other measures to mitigate anxious
behaviours and their consequences.
The 4 S Principle is to reduce the 4 primary trig-
gers of stress when in the dental setting, namely:
Smells (e.g. eugenol and cut dentine);
Sights (e.g. needles, air turbine drills);
Sounds (drilling); and
• Sensations (high frequency vibrations - the
annoyance factor).
Anxiety prevention:
implementing the 4 S principle
in conservative dentistry
By Professor Laurence J. Walsh
“for most
patients the
stimuli for dental
fear are sensory
in nature. By
focussing on
these stimuli,
the clinician
aims to reduce
the anxiety
response at its
Table 1. Consequences
of severe dental anxiety
Avoidance of dental treatment
Cancellation of appointments
Greater economic risk for the practice
Poor compliance with follow-up treatment
Negative expectations of treatment visits
Longer time required for dental treatment
Higher caries prevalence and severity (DMFT)
Greater need for oral rehabilitation
Poor oral health
Reduced self confidence
Feelings of shame and inferiority
Negative thoughts
Sleep disturbances
Crying and aggression
Lower satisfaction with treatment provided
Table 2. Causes of dental anxiety
Fear of pain
Fear of loss of control
Conditioning experiences, such as past trau-
matic dental experiences in childhood Influence
of dentally anxious family members or peers
Sights, sounds and sensations of the dental drill
Sights and sensations of dental local anaes-
thetic injections
Angry and aggressive dental staff
September/October 2007 auxiliary 25
A range of approaches can be used for
this, and they can be mixed and matched to
meet the particular needs of the situation.
Table 3 shows four commonly used alterna-
tive methods for dental restorative care
(Ultra-low speed cutting, atraumatic restora-
tive treatment (ART) with hand instruments,
chemo-mechanical caries removal with
Carisolv, and Erbium lasers), each of which
reduces the smells, sights, sounds and sensa-
tions experienced during restorative dental
care. This list is not meant to be exclusive, as
there are other approaches that could equally
be included, for example polymer bur cut-
ting, air abrasion (alumina powder streams),
particle streams in fluid media (e.g. Durr
Vector ultrasonic with silicon carbide parti-
cles in a fluid medium), and ultrasonic tips
coated with diamond particles.
To these methods should be coupled
effective communication with patients,
expressing sympathy and providing reas-
surance. The next higher level of
intervention is training in relaxation and
breathing techniques. In the most severe
cases, these measures can be used after
providing pharmacological support by
conscious sedation techniques including
oral, inhalation and intravenous sedation.
Relaxation techniques are safe, have no
side effects and give patients control over
their anxiety levels. Like the 4 S methods,
they work by eliminating or reducing the
problem at its cause.
Ultra-low speed cutting leverages the
reduced physical properties of infected car-
ious dentine with its broken and degraded
collagen crosslinks. A slow rotating instru-
ment (e.g. 200 rpm with a #3 or #5 round
bur) will remove this dentine but will not
cut sound dentine to any great extent. This
non-viable dentine has no viable odonto-
blast processes and can also be excavated
by hand (as in the ART method), although
care must be taken that the excavator is
used with a whisking action so that exces-
sive penetration pulpally does not occur.
Patients who are not given LA and undergo
ultralow speed cutting or ART provide
interesting feedback on the experience. In a
classic study in 1987, Ken Anusavice4
(who in the same year authored the interna-
tional guidelines on indications for placing
and replacing restorations) in Florida con-
ducted an intriguing clinical study in which
some 47 patients who were not given an
LA injection underwent restorative care.
Some 34 of these (72%) did not request
local anaesthesia for treatment, although
nearly half (47%) experienced pain. Cut-
ting or removing infected carious dentine,
however, elicited little or no painful sensa-
tions, even though the patients could in
some cases sense diffuse low frequency
vibrations. The pain which was reported
occurred once vital affected or sound den-
tine was cut. The nature of the pain (sharp,
well localized, pin-prick) belies the fact
that the tissue being cut is vital - and there-
fore amenable to healing. This begs the
question, should dentine that can heal be
cut away in the first place?
The same minimal intervention philos-
ophy underlies the chemo-mechanical
caries removal method. This targets col-
lagen in infected dentine because of its
broken crosslinks, which are susceptible
to proteolysis by sodium hypochlorite
and chloramines.5,6
Laser technology for caries removal in
anxious dental patients has been in use for
more than 20 years.7Avoidance of the under-
lying affected and healthy vital dentine is
possible because of selective photo-mechan-
ical and photo-acoustic effects that occur
because of the volume expansion of rapidly
heated water within the carious dentine.8
Typically, patients undergoing cavity prepa-
ration with erbium lasers do not need local
anaesthesia, a fact established from large
scale clinical trials, in which only 2-5% of
patients requested LA - even though many
noted slight, intermittent sensations of
cooling or vague shock-like sensations
during laser pulses. There is a short-term
analgesic effect created by the laser which
attenuates these responses in most cases.
Using one of these four alternative
methods of caries removal (or others), the
clinician can apply the 4 S principle for
restorative care in dentally anxious adult
and child patients. As can be seen from
Blood-injury fear
(condescending remarks,
bad comm’s skills)
Bad Manners
Angry Dentist/ Staff
non-supportive staff
Negative dental
team behaviours
(unfriendly, unaccepting
or reassuring)
Sounds of drills
Waiting room (lay out
and design, content)
Waiting period
Sounds of
screaming patient
Sight of needle
Sensation of drill
Root Canal Treatment
Scaling and root planing
Fillings and
crown preparations
Fear of pain
Vicarious learning
(fearful family members,
bad stories from
friends, movies)
Past trauma and
dental experience
e.g: neuroticism
Figure 1. Some possible interactions in factors relating to dental anxiety. Adapted from Reference 9.
26 auxiliary September/October 2007
Table 3, these methods vary in their
implementation but can all achieve a more
pleasant patient experience. If we con-
sider the high number of patients who
currently avoid dental care, the impact of
using these methods on those population
subgroups can be very significant - as well
as being professionally worthwhile.
1. JM Armfield, AJ Spencer, JF Stewart. Dental fear in
Australia: who’s afraid of the dentist? Australian
Dental Journal 2006; 51(1): 78-85.
2. Brennan DS, Spencer AJ (ARCPOH). Practice pro-
files of Australian private general dental practitioners
Australian Dental Journal 2006; 51(1):91-93, 2006.
3. Powell RN, McEniery TM. The Brisbane Statistical
Division Survey of Adult Dental Health 1984. 2. Soci-
ological aspects of the survey. ADJ 1988; 33(1):14-17.
4. Anusavice KJ, Kincheloe JE. Comparison of pain asso-
ciated with mechanical and chemomechanical removal
of caries. J. of Dental Research 1987; 66(11):1680-1683.
5. Ericson D, Zimmerman M, Raber H, Gotrick B,
Bornstein R, Thorell J. Clinical evaluation of efficacy
and safety of a new method for chemo-mechanical
removal of caries. A multi- centre study. Caries
Research 1999; 33:171-177.
6. Maragakis GM, Hahn P, Hellwig E. Chemomechanical
caries removal: a comprehensive review of the literature.
International Dental Journal 2001; 51:291-299.
7. Hibst R, Keller U. Experimental studies of the
application of the Er:YAG laser on dental hard sub-
stances: I. Measurement of the ablation rate. Lasers in
Surgery and Medicine 1989; 9:338-344.
8. Walsh LJ. The current status of laser applications in
dentistry. Australian Dental Journal 2003; 48:146-155.
9. Hmud R, Walsh LJ. Dental anxiety: causes, compli-
cations and management approaches. International
Dentistry, 2007. In press.
About the author
Professor Laurence J. Walsh is the tech-
nology editor of Australasian Dental
Practice magazine. He has worked in
clinical practice in special needs dentistry
for the past 20 years and contributed to
the development of preventive protocols
for special needs patients.
Table 3. Comparison of four approaches from the 4S perspective
Parameter Ultra-low ART with Carisolv Erbium lasers
speed cutting hand instruments
Reduced need for injected LA Yes Yes Yes Yes
Dominant physical sensations Low freq. vibration Scraping Scraping Popping: shock waves
Likelihood of odontoblastic Moderate Low Very low to nil Very low to nil
pain during caries removal
Basis of selectivity for Lack of Lack of Lack of Increased water
infected carious dentine collagen crosslinks collagen crosslinks collagen crosslinks content
(shear strength) (shear strength) (chemical reaction) (ablation threshold)
Suppressed nociceptor firing No No Possibly, because Yes
of low pH (analgesic effect)
Annoyance factor during Low Low Low Very low
restorative treatment
Dentine ablation
Smell and vapours Dentine cutting Nil Hypochlorite vapour if suction
and chloramines inadequate;
typically nil
Cost of implementation Nil, as existing Nil, as regular Low. Gel is stored Medium to
in terms of equipment burs and low speed spoon excavators refrigerated and high for initial
handpieces are used are used mixed when needed purchase
Tactile sense Yes Yes Yes No, unless
sapphire tips used
Conservative Conservative Gel has no effect Laser will remove
Accessing the carious dentine access form access form on sound tooth structure resin and GIC,
or restorations but not amalgam
Learning curve Low Low Low Medium
Ancillary guides Patient response Patient response Loss of opacity Ablation sound, change
for caries removal in the gel change in fluorescence
Speed of dentine removal Medium Low Low Medium to high
Suitable for adhesive Ye s Ye s Ye s Ye s
materials such as GIC
Antibacterial action No No Yes (sodium Yes (photothermal
hypochlorite) ablation)
... For this reason, the "4S" rule, which is based upon the removal of four of the major primary sensory triggers-sound (drilling), sight (air turbine drill), smell, and sensation (high-frequency vibrations) is used. [1][2][3][4][5][6][7][8] The idea of substituting the drill with Erbium family lasers helps pediatric dentists in the treatment of the hard and soft tissues of the oral cavity safely and efficiently. The Er,Cr:YSGG laser (2780 nm) has proven to be an effective tool for ablating enamel and dentine. ...
... Dental anxiety can be coped with by removing four major primary sensory triggers-sound (drilling), sight (air turbine drill), smell, and sensations (high-frequency vibrations). [1][2][3][4][5][6][7][8] In the present study, pulse rate was found to be significantly higher after the cavity preparation with airotor when compared to the baseline pulse rate. However, no significant difference in pulse rate was observed before and after cavity preparation with the laser. ...
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Aim: To evaluate and compare the pain perception, anxiety level, and acceptance of Er,Cr:YSGG laser (2780 nm) with a conventional rotary method during cavity preparation in children. Materials and methods: In a randomized controlled trial, using split-mouth design thirty 6- to 12-year-old children with 60 carious molars were examined. In one quadrant, cavity was prepared conventionally by airotor while, in the other quadrant, Er,Cr:YSGG laser was used. Anxiety was assessed by measuring pulse rate using a fingertip pulse oximeter, while the pain was measured on the Wong-Baker Faces Pain Rating Scale. After the cavity preparation by both the methods, the child was asked about the preference for future treatment of a carious lesion. Results: Pulse rate was found significantly higher in the airotor group but no significant difference in pulse rate was found in the laser group when compared to the baseline pulse rate. The mean value of pain in the airotor group was slightly higher than the laser group. Fifty-seven percent of children preferred Er,Cr:YSGG laser for cavity preparation in the future. Conclusion: During cavity preparation, Er,Cr:YSGG laser comes out to be more effective and acceptable, as it is less anxiety-provoking and may cause less pain when compared with the airotor. Clinical significance: Er,Cr:YSGG laser helps the children to remain calm during the cavity preparation. How to cite this article: Alia S, Khan SA, Navit S, et al. Comparison of Pain and Anxiety Level Induced by Laser vs Rotary Cavity Preparation: An In Vivo Study. Int J Clin Pediatr Dent 2020;13(6):590-594.
... Despite the revolutions in dental technologies and materials and improved knowledge, a significant percentage of patients still suffer from dental anxiety [6]. This anxiety includes apprehension regarding dentistry and receiving dental care, which normally leads to the avoidance of dental treatment and poor oral health and may cause the deterioration of oral health-related quality of life [7][8][9]. Many investigators have reported that anxious patients have worse periodontal health, fewer filled teeth, and more decayed and missing teeth than non-anxious patients do [10][11][12]. ...
... Many researchers have concentrated on studying dental anxiety in university students [27][28][29][30][31][32][33][34][35][36][37], and the incidence of anxiety ranges from 11% to 27.5% among students at different universities globally [38][39][40]. Higher dental anxiety has been reported in non-dental students than in dental students, which might be because of inadequate dental health education, which leads to high dental anxiety among undergraduate students from non-dental colleges [27][28][29], and additional decreases in dental anxiety have been revealed among dental students during the course of their dental training [9], [41]. Therefore, for these students, it is necessary to study procedures that can assist them in overcoming such anxiety [28]. ...
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The aim was to investigate the dental anxiety and fear levels among students and its relation with their field of study and gender. This cross-sectional study included 720 (360 females and 360 males) which recruited from the collages of Dentistry and Humanities and Social Science in University of Science and Technology in Sana'a, Yemen. Corah's Dental Anxiety Scale (DAS) and Dental fear survey (DFS) was used to measure dental anxiety and fear among the study population. Spearman's correlation was used to analyze the association among the dental anxiety measurements or between DAS and DFS tests. Chi-square tests and linear regression analyses were used to determine the associations between dental anxiety or fear and contextual variables. Out of 720 students enrolled, 713 students (354 males and 359 females) completed and returned the questionnaire having response rate of 99.03%. The association between dental anxiety measurements or the DAS and DFS were statistically significant (p < 0.01). Dental students were less anxious and fear than humanities and social sciences students (p < 0.05). Females were more anxious and fear than males (p < 0.05). Dental anxiety and fear was more associated with female than other contextual variables [for fear (OR = 1.14, p = 0.001); for anxiety (OR = 1.90, p = 0.001)]. Dental anxiety was found to be related to dental fear. Male students were less anxious and fear than female students. Students from medical background faculties were less anxious and fear.
... Sensory-based methods of stress and anxiety management have been proposed to decrease DFA in dental patients. For example, the "4S principle" aims to reduce four triggers of DFA in the environment: sights (e.g., needles and drills), sounds (e.g., drilling), sensations (e.g., vibrations), and smells (e.g., clinical odors) [269,270]; however, this intervention has not yet been studied. The utilization of other sensory-based interventions during dental care has been investigated, with most reporting preliminary success. ...
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Dental fear and anxiety (DFA) is common across the lifespan and represents a barrier to proper oral health behaviors and outcomes. The aim of this study is to present a conceptual model of the relationships between DFA, general anxiety/fear, sensory over-responsivity (SOR), and/or oral health behaviors and outcomes. Two rounds of literature searches were performed using the PubMed database. Included articles examined DFA, general anxiety/fear, SOR, catastrophizing, and/or oral health behaviors and outcomes in typically developing populations across the lifespan. The relationships between the constructs were recorded and organized into a conceptual model. A total of 188 articles were included. The results provided supporting evidence for relationships between DFA and all other constructs included in the model (general anxiety/fear, SOR, poor oral health, irregular dental attendance, dental behavior management problems [DBMP], and need for treatment with pharmacological methods). Additionally, SOR was associated with general anxiety/fear and DBMP; general anxiety/fear was linked to poor oral health, irregular attendance, and DBMP. This model provides a comprehensive view of the relationships between person factors (e.g., general anxiety/fear, SOR, and DFA) and oral health behaviors and outcomes. This is valuable in order to highlight connections between constructs that may be targeted in the development of new interventions to improve oral health behaviors and outcomes as well as the experience of DFA.
... According to the concept of MID, the so-called "4S" principle as a minimally invasive approach in behavioral dentistry is developed. It is based on removing four of the major primary sensory triggers for dental anxiety when in dental settingsight (air turbine drill), sounds (drilling), sensations (high-frequency vibrations), smells [3,4]. It is used most commonly in conjunction with other alternative methods to mitigate anxious behaviors and their consequences. ...
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Dental caries is the most common chronic dental disease in the world. It is defined as a multifactorial microbial infectious disease characterized by demineralization of the inorganic and destruction of the organic substance of the tooth. Conventional treatments for caries removal are often associated with pain and fear. Minimally invasive treatment offers an attractive alternative to managing carious lesions in a more conservative and effective manner, resulting in enhanced preservation of tooth structure. The aim of this review article is to analyze the scientific literature regarding the alternative therapeutic approach to the caries lesion management. A search was performed to summarize the evidence behind the alternative methods for caries removal, including the use of air abrasion, lasers, ultrasonic devices, polymer burs, At-raumatic restorative technique, chemo-mechanical caries removal, and their advantages and disadvantages to be discussed. The findings of the literature review give grounds to undertake studies investigating the efficiency of the different methods for caries removal. Future explorations will be interesting as the profession begins adopting the alternative caries management strategies that may decrease the use of behaviour management techniques in the treatment of paediatric dental patients.
... Medical procedures cause a feeling of fear, inability, as well as anxiety 2 . It can be provoked due to multiple factors, such as previous negative or traumatic experience, sensory triggers such as sights of needles and air-turbine drills, sounds of drilling and screaming, vicarious learning from anxious people, patients' personality characteristics and their coping strategies [3][4][5][6][7][8] . ...
Aim: The successful anesthesia is an essential factor for dental treatment. This study aimed at determining the effectiveness of local anesthesia and it’s relationship with dental Anxiety. Methods: This cross-sectional study was carried out on 256 dental patients, in 2017. Dental Anesthesia was administered after completing the Modified Dental Anxiety Scale by the patients. The level of anesthesia was recorded in one of three states (successful, difficult, and failed). Collected data was analyzed using SPSS version 22 and tests of, Chi-square, independent t-test, analysis of variance, and logistic regression model. Results: About 60.5% subjects had moderate-severe dental anxiety. The mean of dental anxiety significantly was lower in the successful anesthesia group (P<0.01). Patients with elementary education had a significantly higher level of dental anxiety (P<0.01). Dental anxiety was significantly higher in the age group of ≥59 years, compared to the other age groups, except for 49-58 years (P<0.05). Subjects with a significantly higher level of dental anxiety more delayed their visits to the dentist. The logistic regression model showed that the dental anxiety (high anxiety) and literacy level (elementary) were the most important predictors of failed or difficult anesthesia. Conclusion: Informing patients about dental treatment procedures, regular and periodic visits to the dentist, using psychotherapeutic techniques to reduce dental anxiety before anesthesia, could play an important role in the success of anesthesia.
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Dental Fear and Anxiety (DFA) is the fear and anxiety an individual associates with going to the dentist. Researchers are encouraged to find and eliminate DFA since this will improve oral health and quality of life in the long run. Understanding the biology behind fear and anxiety can greatly help us in the management approaches. The amygdala is referred to as a ”fear centre,” and it has been found that fear and anxiety share overlapping neural circuits. As a result, DFA can impact both the patient-dentist relationship and the dental treatment strategy. This article thus aims to discuss the causes of DFA, and also the ways we can overcome it. Dental anxiety is caused by various fears, including fear of pain, blood-injury fears, lack of trust, and so on. It leads to the avoidance of dental care. Psychotherapeutic interventions, pharmaceutical interventions, or a combination of both can be used to manage dental anxiety. On the patient front, they should discuss their fears with the dentist, try to distract themselves, and employ breathing exercises or other mindfulness techniques like those mentioned in the article.
Conference Paper
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Introduction: Cases of pneumothorax have been reported by various authors in patients with COVID-19. The association between these two diseases, as well as its frequency, have not yet been well studied. Aim: To present the first three cases of spontaneous pneumothorax associated with COVID-19 registered in the University Hospital “Sveti Georgi” Plovdiv. Clinical cases: Three cases of pneumothorax associated with COVID-19 were presented in two men aged 76 and 33 years and one woman aged 72 years. All three patients were on mechanical ventilation. They underwent thoracentesis with the placement of a chest drain. Due to the worsening of the underlying disease, all three patients died. Discussion: Pneumothorax associated with COVID-19 has been reported in 1% of patients requiring hospitalization. Association between barotrauma and pneumothorax is observed in the intubated patients in ICU. Another pathogenetic mechanism is the diffuse alveolar damage caused by the virus with the formation of interstitial emphysema and pneumatocele. The surgical method of choice is thoracentesis. The outcome in patients with COVID-19 and pneumothorax depends on the severity of the underlying lung injury. Conclusion: Pneumothorax is a rare but serious complication of COVID-19. It is often associated with poor outcome, especially in patients on mechanical ventilation.
Purpose Oral-maxillofacial surgical procedures like Impacted third molar surgery (ITMS) may lead to increased perioperative anxiety and pain perception in patients. Psychological interventions like meditation have been shown to decrease acute anxiety levels in individuals. The purpose of this study was to investigate the effect of heartfulness (HFN) meditation during ITMS. We hypothesised that heartfulness meditation would reduce the intraoperative anxiety and pain perception in patients undergoing ITMS procedures. Patients and methods The prospective interventional study included 60 participants. They were randomly assigned to heartfulness meditation group (26 participants) and control group (34 participants). The heartfulness meditation group was given meditation before their ITMS procedure. Perioperative anxiety and pain perception was assessed using the Spielberger State - Triat Anxiety Inventory (STAI - T, STAI - S), Modified Dental Anxiety Scale (MDAS) and Numerical Rating Scale (NRS). Descriptive statistics such as frequency, percentage, mean and standard deviation were used to describe the data. Inferential statistics such as Chi-square test, Unpaired T test and Pearson correlation were used to analyse the data. Results The heartfulness meditation group reported less intraoperative anxiety (STAI – S) compared to the control group which was statistically significant (P < 0.002). There was a positive correlation between triat and situational anxiety levels of the participants. There was no significant difference between the groups in relation to dental anxiety and intraoperative pain perception. Conclusion A single session of heartfulness meditation was effective in reducing the intraoperative anxiety levels in impacted third molar surgery. However, its effectiveness in reducing dental anxiety and pain perception was not significant.
Background and purpose Reducing dental anxiety is a major aspect of childmanagement in dental visits. This crossover randomized clinical trial was designed to determine the effect of lavender aromatherapy on anxiety level during dental treatment and pain perception during dental injection in children. Materials and methods Twenty-four children aged 7-9 years received restorative treatment with lavender aromatherapy in the intervention session and without aroma in the control session. Salivary cortisol and pulse rate were measured to evaluate child’s anxiety level and the Face Rating Scale (FRS) was used for assessing the pain perception during injection in both visits. Results The treatment effect on salivary cortisol, pulse rate, and FRS score was -8.01 ± 0.92 nmol/l, -11.17 ± 1.28 (in minutes), and -2.00 ± 0.41 respectively, which was statistically significant (P < 0.001). Conclusion Lavender aromatherapy can decrease dental anxiety and experienced pain in dental setting.
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Previous studies have indicated that a chemomechanical caries removal system (CRS) has been effective in minimizing the use of conventional mechanical instruments and that it may reduce the need for local anesthesia. In the present study, a comparison of the pain experienced both during treatment with a chemomechanical technique and during conventional caries removal (control) was made for each of 47 patients who initially were not given a local anesthetic. One of two dentists was randomly selected to examine and treat patients with a matched pair of carious teeth, and each pair of teeth was treated in a randomized order with the CRS or control procedure. Responses to the McGill Pain Questionnaire (MPQ) revealed a significantly higher level of pain (p < 0.025) associated with the conventional treatment compared with the chemomechanical procedure. A significantly greater number of patients (p<0.05) requested local anesthetic for the tooth subjected to the control procedure than for the tooth subjected to the CRS procedure. However, 72.3% of the patients did not request local anesthesia for either treatment, although pain was experienced by these patients in 46.8% of the control teeth and 27.7% of the teeth which received the CRS treatment. Of the 20 pain descriptor categories listed on the MPQ, the sensory categories accounted for the greatest mean number of pain descriptors selected for both the CRS (4.4) and control procedures (8.0), compared with the mean number of descriptors selected from the affective pain categories for the CRS (0.8) and control procedures (1. 0). These results suggest that sensory pain factors are more important than affective pain factors in controlling the overall discomfort of patients and the need for local anesthetic during caries removal and subsequent restorative procedures.
Up to now lasers have not achieved any practical importance in dentistry for drilling teeth because of considerable damage to the surrounding tissue. We studied the application of pulsed 2.94 microns Er:YAG laser radiation in vitro on extracted teeth to remove enamel, dentin, and carious lesions. The depth and diameter of laser-drilled holes were measured as a function of pulse number and radiant exposure. The tissue removal is very effective both for dentin and enamel.
Participants in the BSD Survey responded to a series of questions designed to elicit information on attitudes to dental care, perceptions of the importance of optimal dental health and factors influencing access to dental care. Over half (56.5 per cent) had attended the dentist in the previous 18 months and of these 45.6 per cent had attended for preventive rather than symptomatic reasons. Expense was identified as the largest single barrier to dental care. Social background and levels of education influenced attitudes to the retention of natural teeth.
The aim of the study was to evaluate the clinical efficacy and safety of a new method (Carisolvtrade mark) for chemo-mechanical removal of caries. At four centres, 137 consecutive patients (64 females and 73 males aged 3-85 years, mean 35) entered a prospective, controlled, randomised open study. One primary caries lesion with distinct dentine involvement was selected per patient. A total of 116 lesions in permanent and 21 in deciduous teeth were selected. Caries was removed with traditional drilling or the new method. Gel was applied onto the carious dentine and the softened caries gently removed with specially designed hand instruments. New gel was applied and the procedure was repeated until no more debris could be removed and the surface was hard as judged by clinical criteria (probing and visual inspection). An independent examiner judged the cavity being caries-free or not, using clinical criteria. One hundred and thirteen patients were randomised for gel treatment and 24 for drilling. Three patients selected for drilling did not complete the treatment. Total caries removal was achieved in 106 cases with gel and in 19 with drilling. The reasons for incomplete caries removal were step-by-step excavation in 5 cases, unsuccessful caries removal in 1 case for each treatment, while 2 cases refused inspection. Mean (+/- SD) time for caries removal was 10.4 (+/-6.1) min with the gel method and 4.4 (+/-2.2) min with drilling. Mean volume of gel used was 0.4 (+/-0.2) ml. Eighty-two of 107 patients perceived that the new method caused less discomfort compared to drilling. Dentine caries was effectively removed using the Carisolv method without any adverse reactions.
Compared to the past, caries removal has become more efficient, however inherent fundamental drawbacks of the drilling approach have remained: unpleasantness to patients, need for local anesthesia, and potential adverse effects to the pulp due to heat and pressure. Chemomechanical caries removal, introduced almost three decades ago, was claimed to be a non-invasive alternative for the removal of carious dentine. In essence, the technique involved applying a solution onto the decayed dentinal tissue, allowing it to soften it, and, finally, scraping it off with blunt hand instruments. The partially degraded collagen in carious dentine was chlorinated by chemomechanical caries removal solutions. This chlorination affected the secondary and/or quaternary structure of collagen, by disrupting hydrogen bonding. Carious material removal was thus facilitated. The purpose of this paper is to perform a comprehensive review of the literature regarding chemomechanical caries removal, including the most recently available product, the initial reports on which warrant renewed interest in the approach.
A range of lasers is now available for use in dentistry. This paper summarizes key current and emerging applications for lasers in clinical practice. A major diagnostic application of low power lasers is the detection of caries, using fluorescence elicited from hydroxyapatite or from bacterial by-products. Laser fluorescence is an effective method for detecting and quantifying incipient occlusal and cervical carious lesions, and with further refinement could be used in the same manner for proximal lesions. Photoactivated dye techniques have been developed which use low power lasers to elicit a photochemical reaction. Photoactivated dye techniques can be used to disinfect root canals, periodontal pockets, cavity preparations and sites of peri-implantitis. Using similar principles, more powerful lasers can be used for photodynamic therapy in the treatment of malignancies of the oral mucosa. Laser-driven photochemical reactions can also be used for tooth whitening. In combination with fluoride, laser irradiation can improve the resistance of tooth structure to demineralization, and this application is of particular benefit for susceptible sites in high caries risk patients. Laser technology for caries removal, cavity preparation and soft tissue surgery is at a high state of refinement, having had several decades of development up to the present time. Used in conjunction with or as a replacement for traditional methods, it is expected that specific laser technologies will become an essential component of contemporary dental practice over the next decade.
This study aimed to describe both the prevalence of dental fear in Australia and to explore the relationship between dental fear and a number of demographic, socio-economic, oral health, insurance and service usage variables. A telephone interview survey of a random sample of 7312 Australian residents, aged five years and over, from all states and territories. The prevalence of high dental fear in the entire sample was 16.1 per cent. A higher percentage of females than males reported high fear (HF). Adults aged 40-64 years old had the highest prevalence of high dental fear with those adults aged 80+ years old having the least. There were also differences between low fear (LF) and HF groups in relation to socioeconomic status (SES), with people from higher SES groups generally having less fear. People with HF were more likely to be dentate, have more missing teeth, be covered by dental insurance and have a longer time since their last visit to a dentist. This study found a high prevalence of dental fear within a contemporary Australian population with numerous differences between individuals with HF and LF in terms of socioeconomic, socio-demographic and self-reported oral health status characteristics.