Vol. 26 No. 04 Oct-Dec 2017

Jamaluddin Syed                           MDSc, BDS 

INTRODUCTION

Historically, the word microscope has been taken from ancient Greek words, mikrós and skopeîn, meaning small and to look or see respectively. The science of investigating small objects using such instruments is called Microscopy.1
In 1926, foundations of geometrical electron optics were already laid later by Hans Busch, German physicist, when he learnt about the trails of charged particles in electric and magnetic fields.2 De Broglie, a French physicist, introduced the concept of corpuscle waves that led to the development of wave electron optics.3 Aforementioned discoveries in the electron optics steered towards the concept of electron microscopy. In 1897, Thompson did the discovery of the electron 1926, Busch discovered the Magnetic/Electric Fields as Lenses while at the same year de Broglie revealed the wave nature of the electron. 1931, Max Knoll and Helmut
Ruska invented the first 1st Transmission Electron Microscope (TEM). Few years later Erwin Wilhelm Müller, a German physicist, invented the Field Emission Electron Microscope. And in 1938 Manfred von Ardenne built the 1st Scanning Transmission Electron Microscope (STEM). Following year Bodo von Borries and Helmut Ruska introduced the 1st Commercial Transmission Electron Microscope having ~10 nm resolution which improved year by year to 1.0 nm in 1965 eventually to 0.2 nm. During 1964-1968, Albert Victor Crewe, a British born American physicist, added a field emission gun with the Scanning Transmission Electron Microscope (STEM) hence raised the resolution further to ~0.3 nm. In 1999 resolution was raised up to < 0.1 nm an in it came to 2009: 0.05 nm.4,5.

1.1.Structure and Working Principle

Scanning Electron Microscopy (SEM) has been an indispensable tool in research since its invention in 19626 and has significantly contributed towards biology, medicine and material sciences research.7-9

Electron Microscopes are scientific devices to examine objects on a very fine scale yielding the information about the topography, morphology, composition and crystallographic information.10 Electron Microscopy permits the scanning of images at high magnification (50x – 10.000x and above).
Basic construction of an electron microscope involves an Electron Gun, Anode, Electromagnetic lens, Scanning coils, Specimen Holder or Stub, Detectors (SE, BSD, EDS and some more).

A highly energetic beam of electrons is bombarded from the electron gun hitting the sample to produce signals that are eventually collected by a detector SE, BSD, EDS as the case may be to scan the surface of the specimen, Saghiri et al.11 In the beginning tungsten material was used to form the tiniest conceivable probe later this source was substituted by LaB6, Transmission Electron and Field Emission guns.
The size of the source of the electron is demagnified by the application of electron optics and this is achieved using condenser lenses and an objective lens. By the objective lens the electron beam is focused on the specimen surface. Magnification is limited by a few key parameters: aberrations of the lenses, particularly the objective lens as it works at large angles of convergence, the electron source brightness,12 and the interaction volume, mainly when the specimens are a bit thick.2

1.2.Electron sources in the electron microscope

The very initial source for electrons in electron microscopy was a thermionic gun consisting of a V-shaped tungsten filament, having a tip of 100 mm in radius. When heated with an electric source this tip starts emitting electrons, at temperature of 2700 K approximately. The thermionic electron source is economical and requires a relatively low vacuum. The tungsten filament is limited to about 100 hours life because of evaporation of its material that makes it thin resulting in its malfunction. The LaB6 gun emitting material, which was introduced later, have a lower work function; therefore the similar amount of electrons can be discharged at lower eating temperatures. For this purpose single-crystal block of LaB6 with a polished tip of 1 mm radius, about 0.5 mm long and about 100 mm in diameter, is used. Subject to the sharpness of the tip, LaB6 gun shows 5-10 times higher brightness and a 10 times longer lifetime when compared to the tungsten filament.2 Lately two types of more electron emission methods were introduced namely; cold field emission (CFE), and thermal field emission (TFE). In cold field emission the lectrons tunnel through the potential barrier due to formation of a high electric field hence leaving the cathode wire at room temperature. Thermal field emission method operates only at a higher temperature similar in principle to the CFE. This is thought to help in keeping a clean tip and minimizing noise in final results. As the brightness is a key perimeter for the resolution in the SEM defining the current available for a given size of the probe that finally sets the recording time per pixel of the image. This increased brightness is successfully achieved from these field-emission sources having a higher brightness, of the order of 109 A/cm2 sr at 20 keV.2,13 When compared with the thermionic emitters, where the effective source size is of the order of 5 mm, field emission exhibits another advantage as the virtual source is small, usually in the 5-25 nm range. Lens aberrations are reduced due to lower demagnification and FEG having low energy spread values as low as 0.35 eV for FEG, n comparison with 1.5 eV or more for a thermionic emitter. Chromatic aberration does not essentially limit the resolution at high energies (>10 keV) and it is a main factor for improvement of low-energy imaging.14

1.3.Signal types in Scanning Electron Microscopy

The Scanning Electron Microscope provides information by three types of signals Secondary Electrons (SE), back-scattered electrons (BSE) and energy dispersive x-ray analysis (EDX or EDS).15 Secondary Electrons (SE) are bombarded on the surface producing an image that can be readily inferred. The sample morphology determines the contrast of that image and therefore a high resolution image is obtained through the help of a small diameter of electron beam.16 Back-scattered lectrons (BSE) are primary beam of electrons redirected from atoms. The image contrast of a back-scattered micrograph is determined from the atomic number of sample elements. The resolution in back scattered electrons (BSE) image cannot be as good as achieved in secondary electrons (SE). However the image formed shows the distribution of a number of chemical phases.17 Mapping of root canal dentin is illustrated in (B, C), (D, E) and (F, G) in the coronal, middle and apical portions, indicating some gutta-percha remnants and dentin chips. By the images the differences in both the detectors can be appreciated. Lighter-contrast particles indicate compositional contrast, further confirming that they are gutta-percha and (A) overview of root canal wall.11

1.4.Sample preparation

The decision should be taken prior whether a sample is suitable to be scanned under Scanning Electron Microscope (SEM). Thickness of a sample not more than 100nm is recommended to get best results. Sample preparation can be done by thinning and polishing the materials mechanically. After this there are different ways of placing the samples on the stubs used for scanning under the electron microscope,

either the samples can be glued with some epoxy glue on the sample holder (stub) or can be sticked with Carbon sticking tapes specially designed for the stubs. When a transmission electron microscope (TEM) is used to scan the data is xtracted from the margins of a hole in the center of that sample, this hole is made by the ion thinning method, a method in which sample is irradiated with Argon (Ar) ions beams in most instances to create a hole. The eventual damage of ion thinning is reduced by metal coating of the sample before this irradiation.18 Therefore scanning with electron microscopy requires care during the sample preparation or else this may affect the analyses and results.

Saghiri et al.11, suggested that cell observation by SEM requires prior application of a fixative like osmium tetroxide and glutaraldehyde. This fixation is generally achieved by incubation in a solution of a buffered chemical, such as glutaraldehyde, which is occasionally combined with formaldehyde and post-fixation with osmium tetroxide remains an option too. Since literature recommends different methodologies, cell adhesion towards surface and other biological interactions might ensue in a different way according to the fixation process.19-21 No studies on the subject of comparison of various methods of fixation for specimens/samples valuated under SEM have been performed till date.

1.5.Coating Samples

SEM scans samples that are electrically conductive. For a non-conductive material a special layer or coating of carbon, gold, platinum is applied on the sample to make it conductive and for this a sputtering coating machine is used to serve the purpose. Few have mentioned the methods for specimen preparation and how the specimens were coated.19,20,22-26

Most articles did not even describe the process of controlling the conductivity of the conductive or non-conductive specimens. There is an understanding that different coating methods for the same samples could generate image artifacts. Similarly, the voltage (HV) or the Vacuum conditions used for scanning the images are generally not detailed in the articles.27

In SEM conventional imaging, the specimens must be conductive electrically, at least at the surface, and it is made sure that they are electrically grounded to prevent the buildup of electrostatic charge superficially. Apart from cleaning and mounting the specimen on a stub, metals require no specific preparation for SEM.11

Non-conductive specimens, like teeth, composites and ceramics likely get charged when scanned under the electron microscope, particularly in Secondary Electron (SE) imaging mode, and this may lead to faults in scanning and presence of other artifacts in imaging, and because of this the samples are generally coated with some electrically-conducting material, as carbon, Gold or platinum, using a low vacuum sputter coating or high vacuum evaporation machine. The accumulation of static electric charge is thus prevented on the specimen for the period of electron irradiation. Saguiri et al.11 mentioned two reasons for coating, even when there is enough specimen conductivity to prevent charging: (a) to increase signal and surface resolution, when the samples are of low atomic number (Z); and (b) betterment in the resolution occurs since backscattering and secondary electron emission near the surface are enhanced and therefore a higher-quality image of the surface is achieved.

2. Dental Applications:

Since its inception and introduction in dental research electron microscopy has a wide range of applications involving Dental Biomaterials and Dental Hard or soft tissues.

1. Evaluation of micro cracks/gaps and deformities in biomaterials and Dental hard tissues.
2. Details of Surface topography and roughness of different Dental Biomaterials /Dental hard Tissues..
3. Details of Subsurface structures of dental Hard tissues/Dental Biomaterials.
4. Differentiate various dental hard tissue and biomaterial structures.
5. Evaluation of bonds between various biomaterials and structures.\

2.1. Evaluation of Dental Biomaterials:

a) In one study scanning electron microscopy was applied to evaluate the marginal integrity of bonded resin composite fillings for posterior teeth to enamel and dentine.28

b) The purpose of the study was the fabrication of dental glass-ceramics to produce bioactive behaviour around the margins of restorations and to provide a bioactive surface which can lead to attachment of periodontal tissue, providing a complete seal of the marginal gap between tooth and fixed prosthesis. Scanning electron microscope assisted in the establishment of the workability of the new composite material to be applied as coating on the base porcelain as well as the bioactive behaviour of the fabricated coated specimens.29,30.

c) Development of a novel surface modification for improved bonding to zirconia. Scanning electron microscopy (SEM) were used to evaluate and quantify failure surfaces.31.

2.2. Dental Hard Tissues:

a) Methods in microscopic imaging, such as scanning electron microscopy (SEM),32-36 transmission electron microscopy (TEM),37-41 can also be applied to identify micromorphological alterations at the interface between enamel/dentine and the dental composite biomaterial.

b) Scanning electron microscopy (SEM) was used for measuring the in vitro resorption of dental hard tissues as one of the earliest techniques31-42 and it is still broadly used till date.43-45

c) Daniela C. Kalthoff in 2011, estimated the microstructure of Dental Hard Tissues in Fossil and Xenarthrans (Mammalia: Folivora and Cingulata) by means of the scanning electron microscopy methods.46

2.3. Oral Soft Tissues:

a) An appreciable amount of small globular mineral deposits on the surfaces of macropores in solid-walled (SW) poly(llactic acid) (PLLA) scaffolds was also revealed by SEM images (Fig. A), while an noticeably larger amount of mineral nodules was observed on nanofibrous (NF) poly(l-lactic acid) (PLLA) scaffolds (Fig. B). This observation was confirmed by energy dispersive x-ray microanalysis, which identified higher calcium content (20.42%) on the NF scaffolds than on the SW scaffolds (9.10%) after 8 weeks of culture.47.

CONCLUSION

For testing material properties of dental hard or soft tissues it is required to have reliable laboratory techniques. However, the validation and reproducibility of previously available methodologies to assess the materials and dental hard or soft tissues topography and elemental analyses were also useful but the introduction of electron microscopy in the dental research remarkably improved the whole idea.

The SEM technology applied in Endodontics permits visualization of root/dentin structures, with altered heights, without changing the focus. As SEM figures are in gray scale, the color of dentin does not effect in achieving a correct focus, a limitation that researchers use to face in optical stereomicroscopes.

Atomic force microscopy, EDS and X-ray photoelectron spectroscopy are generally associated with SEM topographic examination before and after several treatments.24,48-50 SEM techniques are still considered to have limitations to provide indefinable facts for structural features. Researchers
in Dentistry should also be cognizant of the guiding principles when thinking about SEM. Imaging principles standardization is equally significant as the research itself.

Following the correct guidelines and principles makes easier for readers to comprehend how SEM results were acquired. Therefore, the studies can compare their morphological results, using the similar protocols. Although SEM is a substantial tool for research in the discipline of dental research, researchers should give comprehensive evidence while using SEM figures, since the assessment of results is likely when same magnifications are used. Moreover, the sample processing, conductivity, type of microscope for instance tungsten, LaB6 beam microscopes or FEG-SEM is such vital information that should also be revealed in the publication. The interpretation and comparison of results becomes difficult for readers when researchers use SEM technology with the lack of the above mentioned information.

CONFLICT OF INTEREST

None declared

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18. Joachim Mayer, Lucille A. Giannuzzi, Takeo Kamino, and Joseph Michael. TEM Sample Preparation and FIBInduced Damage. Mrs Bulletin, May 2007;volume 32.
19. Coraça-Huber DC, Fille M, Hausdorfer J, Pfaller K, Nogler M. Staphylococcus aureus biofilm formation and antibiotic susceptibility tests on polystyrene and metal surfaces. J Appl Microbiol 2012; 112:1235-43.
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22. Ayobian-Markazi N, Foourutan T, Kharazifar MJ. Comparison of cell viability and morphology of a human osteoblast-like cell line (SaOS-2) seeded on various bone substitute materials: An in vitro study. Dent Res J 2012;9:86- 92.
23. Ballo AM, Xia W, Palmquist A, Lindahl C, Emanuelsson L, Lausmaa J. Bone tissue reactions to biomimetic ionsubstituted apatite surfaces on titanium implants. J R Soc Interface 2012; 9:1615-24.
24. Barkarmo S, Wennerberg A, Hoffman M, Kjellin P, Breding K, Handa P et al. Nano-hydroxyapatite-coated PEEK implants: A pilot study in rabbit bone. J Biomed Mater Res A. 2012 3:1-7.
25. Bonetti GA, Zanarini M, Incerti Parenti S, Lattuca M, Marchionni S, Gatto MR. Evaluation of enamel surfaces after bracket debonding: an in-vivo study with scanning electron microscopy. Am J Orthod Dentofacial Orthop. 2011;140:696-2.
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1. Assistant Professor, Department of Oral Biology, Bhitai Dental and Medical college,
2.Mirpurkhas, Sindh. King Abdul Aziz University, Jeddah, KSA.
Corresponding author: “Dr. Jamaluddin Syed” < drjamalsyed@gmail.com >

Nazish A. Khan1                              BDS, MFDSRCS, FFDRCSI

Richard James2                              MBchB, BDS, LDSRCS, FRCS, FDSRCPS, FDSRCS, LLB

INTRODUCTION

Sialolithiasis is a common condition affecting adult salivary glands, accounting for more than 50% of all salivary conditions.1 One of the post-mortem studies revealed calculi in the salivary glands in 1.2% of the population.2 The male to female predilection is 2:1.3 More than 80% occur in the submandibular gland or its duct, 6% in the parotid gland and 2% in the sublingual gland or minor salivary glands.4 Of the submandibular stones, 80% are intraductal and 20 % are intraglandular.5 Submandibular sialoliths arise mainly due to the tortuous course of the Wharton’s duct around the mylohyoid muscle and the increased concentration of calcium and mucin within the saliva, causing stasis.5 The vast majority of stones present as a single entity, with multiple or simultaneous stones, involving bilateral submandibular glands, being rare; 3-5%.6 We present a case report of six submandibular sialoliths involving the submandibular glands bilaterally.

CASE REPORT

A 27-year old gentleman was referred by his general medical practitioner to the Department of Oral and Maxillofacial Surgery at Norfolk and Norwich University Hospital. He presented with a 10-year history of dry mouth, difficulty swallowing and recurrent spontaneous expulsion of numerous stones from the floor of the mouth bilaterally. On examination, numerous stones were visible bilaterally through the oral mucosa on the floor of the mouth. A lower occlusal radiograph confirmed the presence of 6 concurrent bilateral submandibular stones, which appeared intra-ductal; therefore no further investigations were offered. (Figure 1).

The patient was consented for the removal of these stones under general anaesthetic. Five intra-ductal stones were removed (Figures 2 and 3).

The 6th stone was embedded within the hilum of the gland, in close proximity to the lingual nerve, and was therefore left in situ (Figure 4). Upon reviewing the patient in clinic post operatively, there was no further stigma of dry mouth and the patient did not wish to be followed up in the future as his complaint had resolved.

DISCUSSION

Submandibular gland stones are a common presentation, constituting up to 85% of all salivary stones.7
They normally arise due to stasis within the tortuous Wharton’s duct caused by the accumulation of organic cellular remnants and glycoproteins together with salts and other inorganic matter to form a nidus, or nest, which eventually calcifies.3

The cardinal symptoms include pain and mealtime related swelling. The stones take an elongated shape if they form within the duct, however if they form within the hilum of the gland, they can grow quite large and remain asymptomatic.7 Diagnosis is based on history and a thorough clinical examination. However sometimes submandibular stones can remain asymptomatic if the obstruction is not complete and saliva escapes around the calculi.8
Complete obstruction causes constant pain and swelling, pus may be seen draining from the duct and signs of systemic infection may be present.9

Special investigations can be undertaken to confirm the diagnosis and plan appropriate treatment. Plain radiographs, especially intra oral lower occlusals are quite useful in locating radio-opaque stones. However, not all stones are radiopaque. Plain radiography visualises only 80-90% of submandibular stones and 60% of parotid duct stones, presumably due to differences in the composition of the secretion of the parent glands.10,11
CT scans are the more expensive, yet, the most accurate non-invasive technique described for localising stones.12,13 Sialography allows the whole duct system to be visualized, demonstrating calculi of all sizes and also glandular damage from chronic obstruction.4

Ultrasonography is well established in cases of clinical suspicion of sialolithiasis, it enables not only to visualise the stone, but also the gland.10,11 Treatment is dependent on the location and size of the stones. 88% of salivary calculi are reported to be less than 10mm in size.14
In most cases of small stones, a trial of conservative treatment consisting of gland massage, hydration and salivary substitutes is adopted.15
If conservative measures fail and the stone is sufficiently far forward within the Wharton’s duct, it can be milked forward, or alternatively sialolithotomy can be performed, by placing a trans oral incision directly on the stone. The stone is then grasped and removed and the gland milked.4 Stones located in the middle part of the Wharton’s duct, posterior to the first molar, which cannot be palpated intra orally may require sialadenectomy.16

Newer techniques such as extracorporeal short-wave lithotripsy and endoscopic intracorporeal shockwave lithotripsy are also gaining popularity due to less damage to adjacent structures.17.

The advent of salivary gland endoscopy has been a major advance, in providing an accurate means of diagnosing and locating intraductal obstruction, and also permitting minimally invasive surgery, which successfully relieves blockages not amenable to intraoral approaches.16 Submandibular gland excision is recommended in cases of substantial intra-glandular calculi, which are inaccessible via a trans-oral approach4 and also in cases where the gland has become fibrosed due to recurrent infections.

CONCLUSION

Submandibular sialolithiasis is a common presentation; however bilateral submandibular sialolithiasis is quite rare. Newer and more advanced techniques are on the horizon for accurate diagnosis and treatment of this condition. However, in this rare case of bilateral submandibular sialolithiasis, conventional methods were employed and the patient was treated successfully without any complications and resolution of his symptoms.

CONFLICT OF INTEREST

None declared

REFERENCES

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1. Specialist in Oral and Maxillofacial Surgery,James Cook University Hospital, UK.
2. Consultant Oral and Maxillofacial Surgeon, Norfolk and Norwich University.
Corresponding author: “Dr. Nazish A. Khan ” <aansa19@yahoo.com></aansa19@yahoo.com>

Nazish A. Khan1                              BDS, MFDSRCS, FFDRCSI

Richard James2                              MBchB, BDS, LDSRCS, FRCS, FDSRCPS, FDSRCS, LLB

Jamaluddin Syed                           MDSc, BDS 

Hina Toufique1                                  BDS
Nighat Nisar2                                     MBBS, MCPS, FCPS
Sohail Saadat3                                   BDS, MDS

INTRODUCTION

Every profession and occupation has its own occupation related risks and hazards. Dental practice is no exception. In addition to dental health care professionals, dental technologists are also commonly at risk for professional hazard.1 These include ergonomic, chemical, biological and work place related risks, in addition to usual stress related hazards.2 Different working postures in dental work setup causes many unwelcoming hazards to dental health care professionals. Bernardino Ramazzini et al, the ‘Father of Occupational Medicine’, first perceived that occupation can be an essential component of wellbeing and diseases.3 The dental work force is exposed to different work related risks like anxiety, unfavourably susceptible responses, higher stress levels, percutaneous injury, radiation hazards, musculoskeletal disorders and lawful risks.1,2

The dental environment is additionally associated to exposing of many danger of different microorganisms.4 Irresistible micro organisms found in blood or spit, as an outcome of bacteraemia or viraemia which cause systemic contaminations.5,6 Dental patients and dental labourers exposed to these microorganisms by means of blood, oral or respiratory secretions.6 The organisms infiltrate the body through a cut on the skin while performing either a medicinal procedure, or a dental strategy, either bringing about an unintentional gnawing or masticatory pressure by the patient, or through a needle wound made while injecting anaesthesia.7

Dental technicians exposed to various work related injuries, risks and hazards, many causes reported were presence of different diseases, increase percutaneous presentation rate, infections, radiation, hazardous dental materials, musculoskeletal diseases, dermatitis, respiratory scatters, eye wounds, environmental pollution and mental issues.1,2,4,6

Beside organic dangers and hazards, dental technicians suffered from musculoskeletal diseases, particularly problems of back, neck and shoulders.8,9 The work place related dangers can be prevented by embracing and acquiring precautionary measures by dental technicians and improving the work environment condition.8

There is an additional requirement for proceeding with dental instruction programs in dentistry so dental technicians can refresh themselves with the most recent and more up to date strategies and materials available.10-13 The present study is undertaken to identify different work place related hazards and conditions of dental laboratories among dental technicians in Karachi city.

METHODOLOGY

A cross sectional study was conducted among hundred and thirty two dental technicians in Karachi. The technicians were selected from the seven laboratories of teaching hospitals (Dow University of Health Sciences, Altamash Institute of Medical and Dental Sciences, Jinnah Sind Medical University, Jinnah Medical Dental College , Ziauddin University , Baqai University, Civil Hospital) and sixteen private dental laboratories of Karachi by visiting them at their laboratories through convenience sampling.

The sample size was calculated using online sample size calculator for the prevalence of the commonest occupational hazard among dental laboratory technicians in Alexandria city as 78.71% reported by Hamida et al ,with margin of error at 5% and confidence level at 95%, it was calculated to be 132.1

A questionnaire was administered to the participants to collect socio-demographic and other work place related information. The variables included were, working experience in years, information related to working environment; lighting, ventilation, space, safety precautions and infection control measures.

The self reported symptoms among dental technicians were also recorded regarding Systemic reactions (headache, vertigo, nausea, fatigue, blood pressure, migraine, trauma, indoor Climate, noise, infection, sinusitis), musculoskeletal problems in hand and neck (rigidity, pain, reduced mobility in the muscle, repeated grinding , wax work, prolonged wrong postures, vibration of the hand piece), neurological and vasomotor fingers reactions (numbness, tingling, pricking, reduced holding power and finger spasm), respiratory tract reactions (nose, throat, lung and sinuses), eye, dermal , hearing reactions, and work related stress like time related pressure and managements, deadlines, financial worries, interpersonal relationships and dealing with customers and staff. All participants were assured that responses would remain anonymous and confidential.
Data entry and analysis was done using Statistical Package for Social Sciences (SPSS) version 22. Means and standard deviations were calculated for continuous variables, while frequency and percentages were calculated for categorical variables. Bar charts were used for graphical display of studied variables.

RESULTS

Among hundred and thirty two dental technicians, hundred were males with the mean age of the participants was 31.08 ±8.29 years. The mean year of work experience as a dental technician was found to be 8.08 ±6.90 years (Table 1). Working environment of the laboratories (private and teaching hospitals dental laboratories) were found to be

satisfactory as 67% participants reported good ventilation, 85% participants reported sufficient light system , 62% and 70% participants reported wide working space and good conditioned instruments and equipments in the laboratories respectively (Table 2) while safety precautions measures were not found according to the measures recommended.

Only 60.6% dental laboratories had fire pump facilities and very less dental laboratories had warning alarms for emergency purpose (Table 2). Use of face masks and gloves were the only most commonly used infection control measures by the dental technicians, very less participants were using face shields, protective glasses and white coats (Table 3). Half of the

participants were not vaccinated, did not use autoclaves for sharps and were not washing their hands with anti bacterial soap (Table 3). For hand washing ,only tap water was in use. Observing the results, the most common work related complaints found were factors causing stress (64%), systemic reactions (50.8%) and musculoskeletal problems in hand and neck (43.2%) (Table 4). The most commonest work related complaints was factors causing stress whether personal, occupational, due to heavy work load or financial worries (Table 5).

Result highlighted that stress was found to be most common work place related hazard with contributing factors found were financial worries, quality requirement in relationship and dealing with customers and time related pressure and management (Table 5,fig 1). Headache and pain were found to be the common work place related health hazards of general systemic reaction (Table 5, fig 2) and musculoskeletal problems (Table 5, fig 3) respectively.

DISCUSSION

Occupationally related medical issues in dental speciality have been reported in literature. The study findings showed that work place related occupational hazards are fairly common among the dental technicians, basic facilities to prevent occupational risks and injuries like air vacuum, fire pumps, warning alarms, use of face shields, protective glasses and vaccinations were lacking among dental laboratory technicians. Common work place related hazards reported by dental technicians were job related stress, headaches, and pain.
Most of the technicians reported their workplace conditions with the stress they face while on work. These finding are in consistent with the findings reported from other parts of the world.1,2

Regarding the conditions of workplace, 36.4% participants reported that they have confined space to work in the dental laboratory. This confinement of space alone can lead to many physical as well as psychological hazards including miss-handling of hazardous material and technicians exposure to harmful chemicals and infected human tissue. Similar findings have been reported by other studies conducted in India, USA, Canada and UK.8,14
Technicians exposure to material intended for their safety can also lead to health related problems.15 Almost 13% of the dental technicians reported that they didn’t wear latex gloves due to allergic reactions or irritation. Similar reports were made regarding use of paper masks and face shields.10,12,13,16
In addition, infectious diseases are also very common among dental technicians due to dealing with a variety of patients, some of whom carry different infections.17-20, In our study we found that more than half of the dental technicians were not vaccinated against Hepatitis B. This is an alarming situation given the high burden of the diseases in our community.

Dentistry related professions were frequently seen as unpleasant and various reviews focused on mental stress and stress-related wellbeing issues in the dental health care professionals. A strict time plan and work load were found to be major stressors.21 The condition of equipments, reported by technicians were fairly good. However, presence of safety precautions like fire extinguishers and emergency exit signs were very rare in the private dental laboratories as well as dental laboratories of teaching hospitals of Karachi. This puts both dental practitioners including dentists, dental technicians and patients at life threatening risk in case of any emergency.

CONCLUSION

This study concluded that dental technicians suffered from work related problems like job related stress, headache, musculoskeletal problems, time management and dealing with patients. The working environment of both teaching hospitals and private dental laboratories was satisfactory while safety precautions and infection control measures adopted by the technicians were not according to the measures recommended.

RECOMMENDATIONS

Based on the findings of this study it is recommended that work place environment should be improved in terms of providing safety precaution measures to dental technicians. They should be instructed that all the work related problems among them can be avoided if they use the safety measures in the dental laboratories. All the personal protection measures must be available for the technicians. Attention should be given to reduce stress by improving their salaries to deal financial stress and by giving sufficient working time to avoid work load on them. They should be trained for communication skills to develop interpersonal skills in dealing with patients.

CONFLICT OF INTEREST

None declared

REFERENCES

1. Hamida AA, Hedia AM.. Occupational health problems among a group of dental laboratory technicians in Alexandria City. in Mansoura University. Conference paper. International Alexandria Conference. 2002.
2. Sivakumar I, Arunachalam KS, Solomon EG. Occupational health hazards in a prosthodontic practice: review of risk factors and management strategies. J Adv Prosthodont 2012;4:259-65.
3. Franco G, Franco F. Bernardino Ramazzini: The father of occupational medicine. Am J Public Health 2001;91:1382-82. 4. Harrel SK, Molinari J. Aerosols and splatter in dentistry: a brief review of the literature and infection control implications. J Am Dent Assoc 2004;135:429-37.
4. Harrel, S.K. and J. Molinari, Aerosols and splatter in dentistry: a brief review of the literature and infection control implications. The Journal of the American Dental Association, 2004. 135(4): p. 429-437.
5. Abichandani SJ, Nadiger R. Cross-contamination in dentistry: A comprehensive overview. Chron Young Sci 2013; 4:51-8.
6. Wakefield CW. Laboratory contamination of dental prostheses. J prosthetic dent 1980;44:143-46.
7. Milam S, Giovannitti Jr J. Local anesthetics in dental practice. Dent Clin North Am 1984;28: 493-8.
8. Gopinadh A1, Devi KN, Chiramana S, Manne P, Sampath A, Babu MS. Ergonomics and musculoskeletal disorder: as an occupational hazard in dentistry. J Contemp Dent Pract. 2013;14:299-3.
9. Al-Shehri Z1, Al-Zoughool M Self-reported musculoskeletal symptoms among dentists in Saudi Arabia. Ind Health. 2017;55:338-44.
10. Logothetis DD1, Martinez-Welles JM Reducing bacterial aerosol contamination with a chlorhexidine gluconate prerinse. J Am Dent Assoc. 1995;126:1634-9.
11. Abichandani S, Shaikh S, Nadiger R. Carpal tunnel syndrome-an occupational hazard facing dentistry. Int dent j. 2013;63:230-6.
12. Field E. The use of powdered gloves in dental practice:a cause for concern? J dent 1997; 25:209-14.
13. Babich S, Burakoff R. Occupational hazards of dentistry. A review of literature from 1990. New York state dent j 1997;63: 26-31.
14. Yamalik N. Musculoskeletal disorders (MSDs) and dental practice Part 2. Risk factors for dentistry, magnitude of the problem, prevention, and dental ergonomics. Int dent j 2007;57: 45-54.
15. Lynch M, Neiders M. Risks of occupational exposure to latex gloves. New York state dent j 1998; 64: 35-39.
16. Oliveira ACR. d Síndrome do túnel do carpo na esfera trabalhista. Revista Brasileira de Medicina do Trabalho, 2017;15: 182-92.
17. Lewis M. Herpes simplex virus: an occupational hazard in dentistry. Int dent j 2004;54: 103-11.
18. Mosley JW, White E Viral hepatitis as an occupational hazard of dentists. J Am Dent Assoc. 1975;90: 992-97.
19. Porter S, Lodi G. Hepatitis C virus (HCV)-an occupational risk to dentists? Brit dent j. 1996;180: 473-74.
20. Kuo MYP et al., Low prevalence of hepatitis C virus infection among dentists in Taiwan. J med virol. 1993;40: 10-13.
21. Gorter, R., et al., Measuring work stress among Dutch dentists. Int dent j. 1999;49:144-52.
    

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    1. Lecturer in dept. of Community Dentistry, Dow Dental College, DUHS
    2. Professor in dept. of Community Medicine, Dow University of Health Sciences
    3. Assistant Professor in dept. of Community Dentistry, Dow International College, DUHS
    Corresponding author: Dr. Hina Toufique < dr.hina95@yahoo.com>

Hina Toufique1                                  BDS
Nighat Nisar2                                     MBBS, MCPS, FCPS
Sohail Saadat3                                   BDS, MDS

Wardah Ahmed1                           BDS, MSPH, PhD
Syed Muzzamil Ali Shah2          BDS, Grad.Dip 
Umer Khayyam3                           BDS, MSc
Tanzeela Sheikh4                         BDS
Natasha Anwer5                            BDS

INTRODUCTION

Oral health literacy (OHL) is widely accepted as an individual intangible resource to invest in individual empowerment.1 OHL is defined as “the degree to which individuals have the capacity to obtain, process and understand basic oral health information and services needed to make appropriate health decisions”.2 Thus, OHL is essential for identification of ways to access health related information and its application to control over the healthy life. Therefore, oral health literacy is a pathway to reduce oral health disparities in population. Oral health literacy covers knowledge and reading skills, understanding/comprehension and decision-making skills.3

The inclination of health services from curative to preventive aspects raises the importance of oral health literacy. Globally, many studies linked low OHL of the people with an overall inadequate oral health status, reduced dental appointment keeping behaviour, low understanding medicine leaflets and increased hospital admissions.4-6 Understanding level of OHL is essential for bridging the communication gap between patients and dentists.3 In Pakistan, there is limited literature that identifying barriers in local population. However, deficient communication, perceived health, general literacy level, language barriers and compromised general health status found to be major barriers in accessing other medical care.7 There is considerably high burden of oral diseases that are preventable and OHL has been associated with reduced incidence of oral diseases.5,8,9 Therefore, designing oral health education material according to oral health literacy level of population could help in accessing needed health information and elimination of the barriers. In our setting OHL documentation was found scarce and not measured. This study aimed to measure the OHL level of patients attending private dental hospital and it would facilitate the step towards preventive dentistry in Pakistan.

METHODOLOGY

Cross-sectional descriptive study design was used. The prevalence of 44.3% was taken as reference adequate health literacy among adults with 5% margin of error, 95% confidence interval and the calculated sample size was n=285.3 Medical record number was used for simple random sampling. Every alternate patient with even number was recruited in the study. Patients’ age 18 and above were included in the study. Patients on follow up visits and with severe dental pain or bleeding were excluded from the study. After taking informed consent the validated modified structured Functional Oral Health Literacy questionnaire (OHL-L)3 was administered, consisted of 20 items. The questionnaire consists of demography, oral health knowledge and items to investigate individual’s:

a) Capacity to access; reading and listening (e.g. questions about information sources, preventive strategies, history forms, appointment card).

b) Capacity to process or understand; numeracy skills, understanding of treatment and alternatives (e.g. questions about prescription after extraction, pre and post instructions by dentists).

c) Capacity for decision making skills (e.g. questions about different clinical scenarios such as regarding caries, periodontal disease and oral cancer).

Data collected by principal investigator and two trained house surgeons. Inter-interviewer reliability contained by piloting the questionnaire among 20 patients. The “correct” answers were labeled as 1 and “incorrect” as 0. OHL-L divided in three levels. Cut off values were 0-9 for inadequate OHL, 10-15 marginal OHL and 16-20 for adequate OHL.3,10 Primary objective was to measure oral health literacy and categorize the patients in OHL-levels. Secondary objective was to assess the difference in OHL-L among various age groups, gender, education and profession. SPSS version 20.0 was used for statistical analysis. Cronbach’s alpha was used for questionnaire reliability assessment. Frequency, percentages (gender, age, education and profession), mean and standard deviation (age) were employed as descriptive statistics. Chi square test was used for calculating statistically significance difference of OHLL among demographic variables.

RESULTS

Participants:

A total of 285 participants (131 male and 154 female) were selected in the study. The mean age of participants was 38.2 (standard deviation [SD]= 1.3) ranging from 18 to 69 years. The characteristics of study sample are shown in table 1.

Descriptive findings:

Overall, 32(11.2%) had inadequate, 164(57.5%) had marginal and 89(31.2%) had adequate oral health literacy (Figure 1).There was statistically significant difference among OHL-L with age groups (p=.001) and educational years (p=.002). However, no statistically significant difference between male and female oral health literacy (p= .40) was found. Similarly, no difference among professions (p=.82) and OHL-L was observed (Table 1).

Responses of each item of functional oral health literacy questionnaire were tabulated in Table 2. The major source of oral health information was found to be television 101(35.4%). Respondents found difficulty in understanding dental education materials and magazines 166(59.3%).

Majority of respondents found difficulty in understanding instructions given by dentist 233(81.8%).Similarly, respondents found difficulty in correct decision if they are having b leeding gums while brushing and flossing 143(50.2%).

Reliability:
The Cronbach’s alpha coefficient was found to be 0.828 that interpret as the good internal consistency reliability.

Validity:

Comparison was made among different variables. Previously, it was hypothesized that questionnaire discriminated well among the study subgroups that differed in education. Majority of participants lied in adequate OHL -L had bachelor degree (37%).

DISCUSSION

The results specify that more than half (57.5%) of the study participants had marginal health literacy. The reason could be the study was conducted in urban private hospital with better general literacy level. Similar to other studies, people have low education level scored low in OHLscales.(11, 12) Likewise, other study conducted by Rai S. in the private dental setting found more than half(67%) respondents lied in medium OHL-level.(10) Contrary to this, Naghibi S. reported 16.2 % respondents had marginal OHL and 39.2% had inadequate OHL in general population.(3)Hence, in dental hospitals patients already receiving health information and getting treatments could impact on the OHL scores. Nevertheless, to reduce selection bias and over estimation of the OHL scores, present study conducted on the randomly selected patients who attended dental hospital for the first time.

Findings of the present study showed the significant association of age with OHL. These findings are in accordance with Rai S. and D’Curz.10,13 However, Naghibi S and Tam A found no association of age with OHL.3,14 Contrary to his finding other study by Holtznam JS et. al found that OHL decreases with increasing age.4 In present study almost half of the respondents (49.1%) belonged to age group 30-49 years and majority of respondents (30%) were housewives. This may also interpreted as they are dependent on their spouse or children for decision making. Results also showed majority of the respondents have been associated with any profession and thus, could increase their information sources. However, it is widely accepted that there is no association of gender with OHL.3,4,10

In literature majority of the researchers used oral health literacy instruments in dental settings to measure the level of OHL in patients. Most widely used are Rapid estimate of adult literacy-dentistry (REALD).11,15 Adult Health literacy instrument for Dentistry (AHLID)16 and Health literacy skills instrument (HLSI)17etc. In present study functional oral health literacy instrument have been used. To the best of our knowledge it for the first time that in any dental hospital OHL-Level of the patients have been measured. OHL-L has additionally decision making component contrary to other instruments which only include reading and understanding components of the health literacy.

In developing countries emphasize have not been given on the oral-health related information, lack of sensitization of dentists about oral health literacy needs, complicated dental magazines and materials.18Although more than half of respondents had ability to read English and dental magazines/materials in present study, however, majority of them seek help to fill history forms and understanding the actual meaning of dental magazines/materials. Majority of the participants had accessed information from family, friends, relatives, television and dentists consistent with the findings from study.10 Social interactions have the powerful impact on the individual in Pakistan.19 Dentists as the direct source of information should avoid medical jargon and clearly understand the level of oral health literacy of their patients to reduce the communication barrier.20,21 This could be interpreted as even better OHL, people lacking in decision making abilities that may hinder in better oral health status. Flynn p et. al in their study assessed improved communication between dental hygienists and patients after assessing their OHL-Level.22 Results showed many of the respondents facing difficulty in understanding appointment cards, prescription cards and post treatment instructions. They compromised in decision making for opting treatments. These findings are consistent with Rai S and Baskaradoss J.10,23 Tam A et. al explored the association of OHL with patient’s dental knowledge, understanding and interpretation of oral health information provided through dental written materials. They recommend to incorporating the measured oral health literacy approach to increase the ability of understanding and decision making of the patients.14

In several dental researches it has been evidently proved that OHL associated with better dental appointment keeping behavior,6,23 people with dysfunctional ability to socially interact and self expression (alexithymia),24 better children oral health status,9 regular follow up care,(15) low prevalence of caries and periodontal disease.5 Therefore, OHL considered as the way to access and understand oral health information, interpret the information correctly and implicate in correct decision making.

The current study conducted in urban private hospital setting thus, the external generalizability is questionable. Hence, the future research would be planned to measure OHL in general population of the same area and different areas of the city to determine more precise oral health literacy level of the population. Moreover, patients visiting hospitals were not screened if they visited any private dental clinic prior; this could over estimate the results.

CONCLUSION

The study found marginal oral health literacy in adult population visiting private dental hospital. There is a need to look at the oral health literacy in the context of large systems-social systems, cultural systems, education systems and public health systems. Further investigation is needed to develop appropriate intervention strategies to improve oral health literacy for better oral health outcomes. The effectiveness of the program lies in the fact that people need to understand and interpret it correctly to lead a good quality of life.

ACKNOWLEDGEMENT

Acknowledging all the participants contributing in the study.

DISCLAIMER

The article has not been presented in a conference or published in any abstract book.

CONFLICT OF INTEREST

None to declare.

FUNDING DISCLOSURE

None to declare.

REFERENCES

1. Nutbeam D. The evolving concept of health literacy. Soc Sci Med. 2008 Dec 31;67:2072-8.
2. US Department of Health and Human Services, Office of Disease Prevention and Health Promotion. Healthy People 2010: Understanding and improving health and objectives for improving health. Washington, DC: US Department of Health and Human Services. 2000.
3. Naghibi Sistani MM, Montazeri A, Yazdani R, Murtomaa H. New oral health literacy instrument for public health: development and pilot testing. J investig clin dent. 2014;5:313-21.
4. Holtzman JS, Atchison KA, Gironda MW, Radbod R, Gornbein J. The association between oral health literacy and failed appointments in adults attending a university?based general dental clinic. Community dent oral epidemiol. 2014;42:263-70.
5. Kanupuru KK, Fareed N, Sudhir KM. Relationship Between Oral Health Literacy and Oral Health Status Among College Students. Oral Health Prev Dent.2015;13.
6. Lapidos A, Shaefer HL, Gwozdek A. Toward a better understanding of dental appointment?keeping behavior. Community Dent Oral Epidemiol. 2016;44:85- 91.
7. Irfan FB, Irfan BB, Spiegel DA. Barriers to accessing surgical care in Pakistan: healthcare barrier model and quantitative systematic review. J Surg Res. 2012;176:84- 94.
8. Richards D. Oral diseases affect some 3.9 billion people. Evid Based Dent. 2013;14:35.
9. Bridges SM, Parthasarathy DS, Wong HM, Yiu CK, Au TK, McGrath CP. The relationship between caregiver functional oral health literacy and child oral health status. Patient Educ Couns. 2014 Mar 31;94:411-6.
10. Rai S, Shodan M, Shetty PJ. Conceptual measure of oral health literacy level among patients visiting a private dental institution in Dharwad: A cross-sectional questionnaire study. J Ind Assoc Public Health Dent.2015;1:492.
11. Lee JY RR, Lee SY, Bender D,Ruiz RE. Development of a word recognition instrument to test health literacy in dentistry: the REALD-30 a brief communication. J Public Health Dent. 67. 2007:94-8.
12. Atchison KA GM, Messadi D, Der-Martirosian C. Screening for oral health literacy in an urban dental clinic. J Public Health Dent.. 2010;70:269-75.
13. D’Cruz AM SAM. Health literacy among Indian adults seeking dental care. Dent Res J (Isfahan) 2013;10:20-4.
14. Tam A YO, Atchison KA, Richards JK, Holtzman JS. The association of patients’ oral health literacy and dental school communication tools: a pilot study. J Dent Educ. 2015;79:530-8.
15. Gironda M D-MC, Messadi D, Holtzman J, Atchison K. A brief 20-item dental/medical health literacy screen (REALMD-20 J Public Health Dent. 2013;73:50-5.
16. Stein L, Pettersen KS, Bergdahl M, Bergdahl J. Development and validation of an instrument to assess oral health literacy in Norwegian adult dental patients. Acta Odontol Scand. 2015;73:530-8.
17. Bann CM ML, Berkman ND, Squiers LB. The Health Literacy Skills Instrument: a 10-item short form. J Health Commun. 2012;17:191-202.
18. National Institute of Health (NIH). The invisible barrier: literacy and its relationship with oral health. A report of a workgroup sponsored by the National Institute of Dental and Craniofacial Research, National Institutes of Health. J Public Health Dent 2005; 65: 174-82.
19. Harchandani N. Oral health challenges in Pakistan and approaches to these problems. Pak Oral Dent J 2012;3:497- 501.
20. Barriers and Soulitions to Accessing care. The Academy of General Dentistry (AGD)was developed by the AGD Board. [online] 2012 [ cited 2017 Jan 15]. Available from URL: https://www.agd.org/media/380239/Barriers-andSolutions-to-Accessing-Care.pdf2012.
21. Boles CD LY, November-Rider D. Readability Levels of Dental Patient Education Brochures. J Dent Hygienist. 2016;90:28-34.
22. Flynn P AA, Schwei K, VanWormer J, Skrzypcak K. Assessing Dental Hygienists’ Communication Techniques for Use with Low Oral Health Literacy Patients. J Dent Hygienist.2016;9:162-9.
23. Baskaradoss JK. The association between oral health literacy and missed dental appointments. J Am Dent Assoc. 2016;147:867-74.
24. Stein L BM, Pettersen KS, Bergdahl J. Exploring the association between oral health literacy and alexithymia. Community Dent Health. 2015;32:143-7.

1. Senior Lecturer, dept of Community Health and Preventive Dentistry. Hamdard College of Medicine & Dentistry, Hamdard University.
2. Assistant Professor, dept of Community Health and Preventive Dentistry. Hamdard College of Medicine & Dentistry, Hamdard University.
3. Assistant Professor, dept of Orthodontics. Bhitai Dental & Medical College. Lecturer, dept of Orthodontics. Hamdard College of Medicine & Dentistry ,Hamdard University.
4. Senior House Officer, Dept of Periodontology. Hamdard College of Medicine & Dentistry, Hamdard University.
Corresponding author: “Dr. Wardah Ahmed” < wardahahmed83@hotmail.com >

Wardah Ahmed1                           BDS, MSPH, PhD
Syed Muzzamil Ali Shah2          BDS, Grad.Dip 
Umer Khayyam3                           BDS, MSc
Tanzeela Sheikh4                         BDS
Natasha Anwer5                            BDS

Fareeha Sajjad                         BDS, MPH

INTRODUCTION

Health is a condition of physical, mental, social well-being and not merely the absence of illness or infirmity.1 Dental disease is one of the most prevalent diseases globally.2 The oral health is described as “it is a structural, functional, aesthetic, psychosocial and physiologic state of well-being and necessary for quality of life and general health of an individual.3 Oral hygiene plays a considerable role in oral health maintenance. Inadequate oral hygiene is a major risk factor for the development of oral diseases.4

Oral hygiene is a practice of keeping teeth and mouth clean to avoid dental issues, particularly bad breadth, gingivitis and dental caries. The main reason of keeping oral hygiene is to protect the plaque buildup, sticky layer of the bacteria and food that appears on teeth.5 More than 80 percent persons are affected by dental plaque, making it most communicable disease present among people.6

Oral diseases are believed most significant public health issue owning to their high incidence and main social impact system.7

Dental caries is most prevalent oral disease. It is a chronic sugar dependent communicable disease, affecting the calcified tissue of tooth and causing demineralization of inorganic part with later damage of organic material. Carious tooth can never return to its original condition, although it is treated.8

Maintenance of oral hygiene has an imperative role in the formation of caries. Due to poor oral hygiene the risk of caries can be increased. Carbohydrates boost the chance of tooth decay. The most harmful are sticky foods as they stay on teeth. Recurrent snacking enhances the time that acids are in exposure with tooth surface therefore it is a risk factor as well.9 Other causes includes lack of sufficient fluorides. Fluoride helps in preventing tooth decay through making teeth extra resistant to the acids generated by plaque.10

Dental caries is believed a leading public health dilemma worldwide owing to its high incidence and considerable social impact.11 WHO (World Health Organization) highlights that 60% to 90% of adults and school children have experienced dental caries worldwide, with the disease being most widespread in Latin American and Asian countries.12 Globally, the prevalence of dental caries in 20-64 years age groups is 92% while in 20-30 year group is 85.58 .13 A study conducted in Iraq demonstrated that prevalence of caries is more among females (84.61%) than males (71.63%).8 As per Pathfinder Research carried out in collaboration with World Health Organization in Pakistan, 52% cases in 12-15 years age group and 70% in 35-64 years age group had dental caries. The incidences of dental caries enhanced with age.14 One more study performed in Karachi demonstrated 51% prevalence of caries in 3-6 years age group15. A study undertaken in Lahore showed 60.90% prevalence of dental caries in 3-8 years age group.16

Mostly females have higher score of DMF (decayed, missing and filled) than the same age of males. Although, currently it is supposed that an atmosphere with its standard life style, dietary pattern, culture and socio-economic status can keep a significant impact on the development or resistance of caries than so-called intrinsic ethnic attributes.17

Pupils are separate portion of the population differentiated by a particular age and certain way of the life.18 The entire level of health in young people student life is affected by numerous factors, for example, raised psycho-emotional stress and inadequate social and hygienic conditions. The reliance of increase of the dental disease prevalence from rhythm of the life, level of hygienic culture, education, medical care and dietary habits has been recognized in several investigations.19 The most useful technique to maintain health during study period is medical examination which allows to reveal symptoms of the teeth and gums lesions during early phases and provides total recovery about diagnosed deformities.20 A recent study regarding oral health of students and development of medical programs have explained by several authors.21 This part of population deserves special attention because it is enough large and has a great potential health dentition.18 Females are considered pillars of the society because they have to train future children. Hence there is great need to provide knowledge to the females regarding dental caries and oral hygiene, who are entering in family generation phase, as by boosting oral hygiene most prevalent disease i.e. dental caries could be prevented. Therefore present study aims to know the frequency of dental caries and associated oral hygiene practices in female college students.

The strength of this study was that it can be generalized to the female population who are studying in colleges of Lahore, as the samples were selected randomly to ensure that the results will be representative of the population studied. Moreover standardized approach was used which permits the study to be replicated in different areas or over time with the production of comparable findings.

In contrast the limitation of this study includes that it was limited to female students studying in college, No similar study was present in Lahore of this age group for comparison of results.

METHODOLOGY

It was cross-sectional descriptive study in which 80 female students of Government College of Home Economics, Gulberg Lahore were included. The inclusion criteria was female students enrolled in BS program while the exclusion criteria was students who were absent, unwilling to participate and already receiving any dental treatment. The duration of study was three months (from Feb. to April 2016). Simple random sampling technique was used. There were total 4 level of classes (1st year to 4th year) in the college. In each class there were 200 students, making total of 800 students. From each class researcher selected 10% of students. Data was collected through questionnaire (circulated in each class by its class representative), which was first pretested in small setup and then was submitted to the students who afterwards were checked by the examiner for DMFT scoring, it was then entered into computer using SPSS 17.0. Frequencies and percentages were calculated and data was presented in tabulation form. Confidentiality of the data was ensured and proper consent was obtained before data collection.

RESULTS

Response rate was 100%, as random students who were willing to participate were selected.

Among 80 female college students, 8(10.0%) were <18 years old and majority 64 (80.0%) was 19-22 years old while 8 (10.0%) students were more than 22 years old (Table-1). Among 80 students, 30 (37.5%) cleaned their teeth twice a day while majority 40 (50.0%) once a day and only 10 (12.5%) students cleaned their teeth occasionally. As far as different methods for teeth cleaning are concerned, table describes that all (100.0%) students used toothbrush.

Among them 28 (35.0%) also used toothpicks, 14 (17.5%) thread (dental floss),4 (5.0%) Miswak,34(42.5%) mouthwash and 14 (17.5%) students used sugar free gums to clean their teeth. Among 80 students,52 (65.0%) explained that they use a toothpaste that contains fluoride and only 2 (2.5%) said no while 26(32.5%) students were not aware about fluoride (Table-2.) Among 80 students, 40 (52.5%) had no decayed, 24(30.0%) had 1 decayed and 8 (10.0%) had 2 decayed while 6 (7.5%) students had >2 decayed. The mean decayed was 0.92. Likewise among 80 students, majority 66 (82.5%) had 0 missed tooth, 10(12.5%) had 1 missed tooth and 2 (2.5%) had 2 missed teeth while 2(2.5%) students had >2 missed teeth. The mean missed was 0.28.

Among 80 students, 40 (50.0%) had 0 filled tooth, 24 (30.0%) had 1 filled tooth and 6 (7.5%) had 2 filled teeth while 10(12.5%) students had >2 filled teeth. The mean filled was 1.10 (Table-3).

Among 80 students, 20 (25.0%) had 0 DMFT score, 14(17.5%) had 1 DMFT score, 22(27.5%) students had 2 DMFT score and 10 (12.5%) had 3 DMFT score while 14 (17.5%) students had >3 DMFT score. The mean DMFT score was 2.30 (Table-4)

Table-2: Distribution of female students by oral hygiene practices

DISCUSSION

Present study was conducted to assess the frequency of dental caries and oral hygiene practices among female college students of Government College of Home Economics, Gulberg Lahore. To acquire appropriate outcomes, a group of 80 students (first year to fourth years) was included in the study and found that mainstream of students was 19-22 years old while few of them were less than 18 or more than 22 years old.

Regular teeth cleaning is good habit that prevents people not only from dental caries but also from numerous oral diseases. Study revealed that major proportion (50.0%) of students cleaned their teeth once daily, followed by twice daily (37.5%) and occasionally (12.5%). The results of the study conducted by Kakkad and coworkers (2014) exhibited better scenario than our study results who reported that 30.8% students cleaned their teeth once daily, majority (67.0%) twice daily while 1.0% and 1.2% more than twice and after every meal, respectively.22 Another study carried out by Manna and coworkers (2014) showed that 36.4% female students cleaned their teeth at night.23

These days toothbrush is considered one of the best instruments for teeth cleaning while significant role of toothpaste can also not be ignored in preventing dental caries and mainstream of population use tooth paste with brush for teeth cleaning. It is important to mention that 100.0% student used toothbrush for teeth cleaning. Study further revealed that 35.0%, 17.5%, 5.0%, 42.5% and 17.5% used toothpicks, thread (dental floss), Miswak, mouthwash and sugar free gums to clean their teeth, respectively. Manna and coworkers (2014) asserted in their study that virtually 67.4% students used toothbrush and toothpaste regularly for tooth cleaning while the other materials were floss (2.3%), toothpick (2.3%), charcoal (0.8%) and chew stick (0.8%).23 Fluoride is extremely beneficial in preventing caries and making teeth stronger. Study revealed that more than half of female students used tooth paste that contained fluoride. Study highlighted that more than half of the female students had no decayed while 47.5% had decayed teeth. The results of our study exhibited better scenario than the study conducted by Kaur and teammates (2010) who asserted that 70.0% female students had decayed teeth.24 While the study undertaken by Manna and coworkers (2014) showed better results that only 19% female students had complain of having decayed teeth.23 When missed or filled teeth were assessed among female college students, study divulged that only 17.5% had missing and 50.0% had filled teeth. Though the prevalence of filled teeth is higher in our study population but still results of our study are better than the study carried out by El-Khateeb and colleagues (2015) who reported that 56.5% females had missing and 61.8% had filled teeth.25

During study DMFT score of female college students was also assessed and found that 25.0% students had 0 score, 17.5% had 1 score, 27.5% had 2 scores and 12.5% had 3 scores while 17.5% had >3 scores. The results of the study conducted by Manna and coworkers (2014) are better than our study result who confirmed that majority (62.8%) had 0 DMFT score while 14.4%, 14.4%, 2.3% and 6.1% had 1, 2, 3 and >3 scores, respectively.23 The overall mean DMFT was 2.30 among female college students while the study done by Al Essa and assoicates (2007) showed that overall mean DMFT was 10.01.26 Another study undertaken by Fayaz and Sivakumaar (2014) showed almost similar results who reported that DMFT score of female students was 2.32.1 Study was limited to female students of Government College of Home Economics, Gulberg Lahore.

CONCLUSION

Study found most of the students were 19-22 years old. All of them used toothbrush while significant majority used toothpaste with brush for teeth cleaning. Major proportion brushed their teeth once or twice daily. Use of fluoride was observed among most of the students. Overall oral health of female students was found satisfactory. The mean DMFT score was 2.30. Health education programs at college level are essential to prevent female students from dental caries.

CONFLICT OF INTEREST

None declared

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Institute of Public Health, Lahore
Corresponding author: “Dr. Fareeha Sajjad” < f-m-100@hotmail.com >

Fareeha Sajjad                         BDS, MPH