Antibacterial Efficacy of Silver Nanoparticles Impregnated Calcium Hydroxide: An in Vitro Study

Zudia Riaz                         BDS
Muhammad Raza             BDS, FCPS, MPH
Amjad Hanif                     BDS, MSc
Beenish Haider                BDS
Sadia Akram                    BDS
Shamayem Safdar          BDS, M.Phil

 

 

OBJECTIVE: To compare the in-vitro antibacterial effectiveness in terms of enterococcus faecalis elimination of conventional
unmodified calcium hydroxide paste with an experimental calcium hydroxide impregnated with 1% silver nanoparticles.
METHODOLOGY: This in vitro study was conducted during the period July 2019 - January 2020 at Materials Research
Laboratory, Centralized Resource Laboratory (University of Peshawar) and Pathology Laboratory (Peshawar Medical College).
Sixty human premolar teeth having single root with mature apices were obtained. These were distributed into two groups
randomly (n=30); experimental group for testing the antibacterial efficacy of calcium hydroxide impregnated with 0.1% by
weight silver nanoparticles and the other was used as a control group for testing the antibacterial efficacy of unmodified calcium
hydroxide. Dentine specimens (size 4 x 4x 1mm) were prepared from the teeth using slow speed cutting saw machine. Smear
layer was removed with EDTA. Specimens were autoclaved to sterilize them. Then each specimen was contaminated with
enterococcus faecalis and incubated anaerobically for 24 hours at 37?C. After the application of medicaments, the zone of
inhibition was measured and number of viable bacteria were determined using SEM. Statistical significance was calculated
using t-test. p<0.05 was taken as significant.
RESULTS: After the application of medicament, the zone of inhibition was greater (9.63mm) in experimental group when
compared to control group (4mm) (p<0.001). Number of viable bacteria before application of medicament were 239 and 208
while after application of medicament reduced to 90 and 54 in control and experimental groups respectively (p<0.001).
CONCLUSION: The addition of silver nanoparticles to calcium hydroxide significantly enhanced its potential to eliminate
biofilm of enterococcus faecalis on dentin specimens.
KEYWORDS: Silver nanoparticles, Calcium hydroxide, Root canal infections, Root canal medicament.
HOW TO CITE: Riaz Z, Raza M, Hanif A, Haider B, Akram S, Safdar S. Antibacterial efficacy of silver nanoparticles
impregnated calcium hydroxide: An in vitro study. J Pak Dent Assoc 2022;31(1):1-4.
DOI: https://doi.org/10.25301/JPDA.311.1
Received: 05 April 2021, Accepted: 08 September 2021


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A Proposed Curriculum for 5-years BDS Programme in Pakistan and its Comparison with the Curricula Suggested by PMDC and HEC

Farhan Raza Khan                         BDS, MS, MCPS, FCPS

In Pakistan, whether to enforce a 4-year BDS course versus a 5-year course, is a matter of debate that warrants multiple deliberations. In USA and Canada, dentistry is 4-year long course but students can apply for admission into dental school only when they have already done 16 years of schooling (i.e. a 4-years of graduate university education is the pre-requisite). On the other hand, In UK & Ireland, students can apply for admission into dental colleges with 12-years of high school education. However, they follow a 5-years BDS programme. Similarly, there is much difference on the emphasis on various subjects taught
in the dental programmes. This paper critically appraises the PMDC and HEC advised BDS curricula in Pakistan and suggests an alternative curriculum that is more balanced in terms of subject distribution, assessment and above all contemporary to cater the evolving needs of the dynamic discipline of dentistry.
KEYWORDS: Dental; education; curriculum; Pakistan
HOW TO CITE: Khan FR. A Proposed curriculum for 5-years BDS Programme in Pakistan and its comparison with the curricula suggested by PMDC and HEC. J Pak Dent Assoc 2020;29(4):169-171.
DOI: https://doi.org/10.25301/JPDA.294.169
Received: 10 June 2020, Accepted: 24 August 2020

The dental school curriculum varies from institution to institution and country to country but most colleges and universities follow a general structure that is in the first two years of dentistry course, students spend most of their time studying basic biological & biomedical science. They learn the structure and function of the human body and the diseases that can affect it. Then in next 2 to 3 years (depending upon the course is 4 or 5 year-long) there is a gradual transition towards more clinically oriented subjects.1 The goal is to prepare dental graduates who possess strong knowledge base, right set of skills, and values essential to the practice of safe and ethical dentistry. Moreover, dental curriculum is built around some essential themes that could inculcate attributes such as professionalism, life-long learning and ability to critically evaluate, correlate and synthesize scientific evidence to help the graduate remain current and up-to-date in clinical practice.
In Pakistan, there are 55 recognized dental colleges.2 Presently, the Bachelors of Dental Surgery (BDS) course
is four-years duration.3 Its existing curriculum is devised by the statutory body of the country, Pakistan Medical &
Dental Council (PMDC). However, the institution responsible for other degree awarding courses in the country, Higher Education Commission (HEC) has also placed a 5-year long curriculum on their website for long4, but for various reasons this curriculum has not been made to any use as hardly any institution in the country follows it.
Whether to enforce a 4-years BDS course versus a 5-years programme, is a matter of debate that warrants multiple deliberations. In US and Canada, dentistry is 4-year long course but students there get admission into
dental school when they have already done 16 years of schooling (i.e. a 4 years of graduate university education is the pre-requisite). In UK & Ireland, students can apply for admission into dental colleges with 12 years of high school education. However, they follow a 5-years BDS programme. In simpler words, a dental graduate in UK & Ireland is generally three year younger than his North American counterpart. As medical and dental education in Pakistan and India, follow British system of education, 5 thus it’s imperative to align our BDS curriculum and assessment methodologies with the prototype so that dental graduates trained in Pakistan don’t face challenges when they apply for equivalence or when they go abroad for further education or apply for registration to practice outside Pakistan.
This paper is to critically appraise the PMDC and HEC advised BDS curricula and suggest an alternate curriculum
that is more balanced in terms of subject distribution, assessment and above all contemporary to cater the evolving
needs of the dynamic discipline of dentistry.

CRITICAL ANALYSIS AND PROPOSAL

The shortcomings in the PMDC curriculum (table 1) are: Firstly, it’s a four year curriculum which needs overhauling as the quantum of knowledge in dental sciences have grown so much in last 40 years that it’s not possible to cover the fundamentals of dental sciences in just four

Table 1: Existing curriculum by Pakistan Medical & Dental Council (PMDC)

Ω As per the state regulation, Pakistan Studies, Islamiat/ Ethics examination to be done at the end of first year.
*Source: PMDC website: http://www.pmdc.org.pk/

years. Moreover, the countries from which this four year BDS curriculum was adopted (UK, Ireland and Australia)
have already moved to the five year program in late 90’s. Thus, it’s likely that Pakistan too will follow their foot step
and will move to 5-years BDS programme soon.
Endodontics is entirely missing as a main subject. It should be specifically mentioned annexed to Operative Dentistry. Oral Medicine is being paired with Periodontology, it should have been synched with Oral Pathology instead. No mention of subjects such as Behavioral Sciences, Ethics, Implant Dentistry, Forensic Odontology etc. Although, Pediatric Dentistry has recently been recommended to be established as separate subject but so far only a few institutions have established its departments. The problem in Pediatric Dentistry teaching and assessment is the post graduate programme and availability of trained faculty.6,7
The limitations of the HEC dental curriculum (table 2) are: An unequal distribution of subjects throughout the length of the course. The final year is over burdened with too many subjects. Periodontology is taught in year 3 and then in year 5, skipping year 4 and not mentioned as which year its examination will be carried out. Similarly, Operative Dentistry is being taught in year 3 and 5, skipping year 4. Pediatric Dentistry is being merged with Operative Dentistry whereas Endodontics is absolutely ignored in the list of subjects. Again, year 4 is skipped for Oral Medicine, Oral Diagnosis & Oral Radiology. These three are clustered as one subject and repeated in year 3 and 5 too. Oral Medicine should have been paired with Oral Pathology to make more

Table 2: BDS Curriculum proposed by Higher Education Commission of Pakistan (HEC)

*Source: HEC website: https://hec.gov.pk

sense. Subjects such as Comprehensive Care Dentistry and Special Care Dentistry have been mentioned but there no
specialty residency programs in the country to train faculty in these subjects.
The strengths of the curriculum (table 3) proposed in this paper are: Its more balanced in terms of subject distribution, assessment and above all contemporary as it has subjects such as ethics, behavioral sciences, implant dentistry to cater the evolving needs of dentistry. However,

Table 3: Distribution of subjects in the 5-year long BDS course proposed in this paper

Ω As per the state regulation, Pakistan Studies, Islamiat/ Ethics examination to be done at the end of first year.

there is a question that there are lack of subject expert teachers in few of these disciplines, especially the newly proposed ones. For this, a solution has been proposed for identifying suitable subject teacher and the best alternate while keeping the circumstances of Pakistan dental academia in context. The first two years are preclinical years where student journals can be used for the formative assessment of the student. The third year is a blend of basic and clinical sciences whereas years 4 & 5 will be clinical years focused entirely on dental subjects. In addition to summative

Table 4: Allocation of faculty in subject of expertise and cross-subject allocation

*The alternate teaching faculty would a make shift (short term arrangement) for next 5 years only, once the number of adequate subjects specialist are available, this practice will be permanently stopped

assessment at the year-end, student log book in each subject could be used as an evidence of competence gained and
formative assessment throughout year.
Although a number of deliberations have been made by subject experts and dental educationists at the 1st Pioneer
Conference on Dental Education held at the Dental Institute of the Liaquat University of Medical & Health Sciences (LUMHS) Hyderabad, Pakistan on 14-15 November 2014 and at Pakistan Pioneer National Seminar on Dental Education organized by LUMHS held at Governor House Sindh (Pakistan) on 20 February 2015. The outcome of
such deliberations have yet to be translated into actions.
In conclusion, the limitations of PMDC and HEC templates have been appraised above. However, comparing the two
curricula, it seems that PMDC version is more practical compared to what HEC has suggested. In essence, the curriculum proposed here is a modified version of PMDC’s existing curriculum. Only fifth year is added, new subjects relevant to international and local practice needs are incorporated and existing subjects are redistributed.

CONFLICT OF INTEREST

None

FUNDING

None

REFERENCES

  1. American Dental Education Association. Dental school curriculum. https://www.adea.org/GoDental/Future_Dentists/Dental_School_ Curriculum.aspx [accessed 29 June, 2020].
  2. Pakistan Medical & Dental Council. Recognized dental college in Pakistan. http://www.pmdc.org.pk/recognizeddentalcollegesinpakistan/ tabid/167/default.aspx [accessed 29 July 2020].
  3. Pakistan Medical & Dental Council and Higher Education Commission Islamabad Pakistan. Curriculum of BDS. Published 2003. Available at: http://www.pmdc.org.pk/ LinkClick. aspx?fileticket=06HF%2Blta1uc%3D accessed 29 July 2020].
  4. Higher Education Commission Islamabad Pakistan. . Curriculum of bachelor of dental surgery (BDS). Five years programme -Revised 2011. https://hec.gov.pk/english/services/universities/RevisedCurricula/Documents/2010-2011/Draft-BDS-2011.pdf [accessed 29 July, 2020].
  5. Khan FR. Similarities and differences in specialty training of Conservative Dentistry and Endodontics (India), Operative Dentistry (Pakistan) and Restorative Dentistry- Endodontics (United Kingdom). J Pak Med Assoc. 2020;70:320-3. https://doi.org/10.5455/JPMA.2934
  6. Khan FR, Mahmud S, Rahman M. Pediatric dentistry training for dentists in Pakistan. J Pak Dent Assoc. 2013; 22:03-8.
  7. Khan FR, Mahmud S, Rahman M. The need of paediatric dentistry specialists in Pakistan. J Coll Physicians Surg Pak. 2013;23:305-7. PMID: 23552549.

  1. Associate Professor, Operative Dentistry, Chief of Dental Services, Aga Khan University Karachi, Pakistan.
    Corresponding author: “Dr. Farhan Raza Khan” < farhan.raza@aku.edu >

Nibrin Double Strand Breakage and its Role in Development of Cancers

Fizza Abidi                                               BDS

Mervyn Hossein                                     FDSRCS(Ed), FDSRCS, FFDRCSI

Saima Akram                                          BSc, BDS, MDS

Angabeen Anjum                                   BDS

The human genetic information has been orchestrated by DNA-damage response pathways. DNA damage response, DNA repair,programmed apoptosis and cell cycle progession are responsible for maintaining the genomic integrity, they initiates the process of tumorigenesis if they are not regulated properly.An article research was done through Google Scholar, Pubmed and was used for an electronic search of articles, using the following keywords: Double stranded breakage, Nibrin, P95, NBS1.The aim of the review is to point out the impact of double strand breakage and the role of Nibrin in development of cancers. The double strand breakage are pathological insults for all the microorganisms because they can cause the elimination of the essential genetic information, which results in the destruction of DNA replication Nibrin is the first DNA repair gene whose overexpression can promotes the process of tumorigenesis by the activation of phosphoinositol 3 kinase /akt pathways.
KEYWORDS: Nibrin, Double strand breakage, P95, NBS1.
HOW TO CITE: Abidi F, Hossein M, Akram S, Anjum A. Nibrin double strand breakage and its role in development of cancers. J Pak Dent Assoc 2020;29(2):94-99.
DOI: https://doi.org/10.25301/JPDA.292.94
Received: 18 April 2019, Accepted: 17 February 2020

INTRODUCTION

The integrity of the human genome is maintained by DNA damage response pathways which includes DNA repairing, chromatin remodelling, cell cycle checkpoint regulation and apoptosis.1-3 There are different types of DNA damage repair pathways which include Nucleotide excision repair (NER) pathway, Base excision
repair pathway(BER), Mismatch excision repair(MER) pathway and Double strand breakage repair (DSB) pathway
and if these pathways are not regulated properly then leads to the process of tumourigenesis.4 The DNA repair mechanism failure and the risk factor for the familial genetic cancer had been established earlier, from last 20 years studies had reported the possible association of genetic polymorphism and cancer formation.5 An electronic article search was done by using keywords Nibrin, NBS1, DNA Damage Response Pathway (DDR) and P95on Google Scholar, PubMed. Different types of research articles including original, review, clinical observation, case reports, longitudinal studies and randomized con trolled trials were selected. The aim of the review is to point out the impact of double-strand breakage and the role of Nibrin in development of cancers.
The double-strand breakages are pathological insults for all microorganisms because they can cause the gain or loss
of the essential genetic information, leading to the genetic transformation which provokes the process of tumourigenesis. DNA replication stress are the main causative factor for endogenous double strand breakage. The double strand breakage are responsible for the destruction of the genetic information by lethal metabolites includes UV radiation, products of cellular metabolism, harmful chemicals and toxins. Scientist has been working for the last 40 years to discover the specific critical role of DSB to understand the phenomenon.5-7 There are 800 DNA damages occurring per hour, estimated upto 19,200 DNA damages occurring daily.8,9
In humans, The DNA damage may increase the process oftumour formation if they remain unchecked. There are
different pathways to conserve the integrity of the human genome by controlling the DNA damage repair and controlling the program cell death.4,10
The Double strand breakage of DNA consists of 2 important pathways: Non-homologous end joining (NHEJ) and the Homologous repair pathway, In non homologous pathway DNA breaks down occurs and the broken DNA
strand is covered by specific enzymes .The Non-homologous repair are independent on homologous template, the double strand breakage are detected by sensor proteins, that causes activation of proximal kinases such as ATM and MRN complex ., However, Nibrin plays an pivotal role by controlling the enzymatic activity of these proteins ( MRE
11and Rad 50) by identifying the damage sites in DoubleStranded Breakages within 5 minutes that is called as Nibrin relocalization, Nibrin is phosphorylated by ATM in response to DNA damage that is called as Nibrin phosphorylation, this process of phosphorylation plays an important role in cell cycle S phase checkpoint activation.11-13
Homologous repair are error-free whereas they require homologous template such as sister chromatid. The DNA
end-resection enzymes which includes MRE11-RAD50- NBS1(MRN complex), the CtIP, Exonuclease 1 plays an important role in the formation of single stranded DNA, Whereas RAD 18 involves in the process of translation of
DNA synthesis. The non-homologous end-joining contains the group of DNA dependent protein kinases (kuo, ligases, nuclease, and polymerase) which are responsible for converting the non-ligating proteins to ligating protein in the presence of factors for protein alignment which act as a caretaker for genomic stability and chromosomal aberrations in the immune system. Thus, DNA ligases IV are the characteristic hallmark of the NHEJ pathways.Deficiency of DNA ligase IV will increase the immunodeficiency and radiosensitivity in the phenotypes and are known as NIJMEGEN BREAKAGE SYNDROME in which there is a defective formation of a protein called Nibrin.14-16
The nibrin protein interacts with functional proteins like ataxia-telangiectasia associated protein(ATR), histones
modifying enzymes such as RNF20 and chromatin remodelling granules (nucleolin). These useful interactions
perform a major role in DSB pathways and a pivotal role in cell cycle regulation.9
Nibrin/p95/ NBS1 is a protein formed by a defective gene NBS gene and it is an important member of the DNA
double-strand break (DSB) repair complex (hMre11 complex) located on human chromosome 8q21 and act as a cell cycle s phase checkpoint.8
The MRN complex a trimeric combination ofMre11, Rad 50, & NBs1. This Nibrin containing protein complex plays a crucial role in regulating numerous phases of doublestrand breakage and repair pathways.17,18 A 754 amino acid containing protein Nibrin, consists of three districts: the N-end containing forkhead-associated domain and two breast cancer-associated domains ( BRCA and carboxy-terminal BRCT), a Central region containing Ataxia telangiectasia mutated kinase (ATM Kinase) and C-terminal for the binding site of MRN complex (MRE 11 and ATM binding Domain). Recent investigations showed that greater than 600 polymorphism variants of Nibrin gene had been reported.17,19
Researchers have reported that more than 10 mutations of Nibrin had been observed earlier and are more frequent in Polish and Czech populations. However, the most frequent mutation of Nibrin is 5 base pair deletion (657del5) in the NBS1 gene which is accountable for a reduction of protein size, i.e. truncation of the Nibrin protein (p95) into two uneven reduced protein fragments which include p26 and p70. (NIBRIN).11,20,21 Nibrin acts as a guardian maintaining genomic stability because it is a presenter of chromosomal dysfunction. Any mutation in the MRN complex due to SNPS or reduction in full length nibrin protein formation stimulates the process of double-strand breakage by increasing the mis-localizationof Mre11 and Rad 50 in the cytoplasm of the cells. All these cyclic events cause a deficiency of protein kinases, which stimulates the formation of Nijmegen breakage syndrome.12,22
The Nijmegen syndrome is an autosomal recessive disorder specified by a mutation in the N BN gene, loss of
chromosomal stability, increased insensitivity to ionization radiation, immunodeficiency, mental retardation and ovarian insufficiency. The major life-threatening complication of Nijmegen syndrome is lymphoma in childhood.23-25

ACTIVATION OF NIBRIN

Nibrin is activated by proto-oncogenes such as C-MYC. The function of C-MYC includes diverse cellular functions
such as cell formation and maintains the integrity of cellular metabolism. Deregulated overexpression of c-myc occurs in a broad range of human cancers and is often associated with aggressive, poorly differentiated phenotypes.
Overexpression of oncoprotein C-MYC is associated with cancer formation in humans, which further stimulates the
overexpression of Nibrin which causes downstream Activation of Phosphatidylinositol (PI) 3-kinase/Akt pathway, this pathway regulates the cellular proliferation, cellular growth and cellular survival. , Phosphatidylinositol (PI) 3-kinase causes down-regulation of tyrosine kinase growth receptors. and activation of phosphorylation of Akt (protein kinase BPKB) controls the cell proliferation and survival proteins e.g. glycogen synthase kinase-3 , GSK3,BAD and cell growth proteins.Thus PI3-kinase/Akt pathway regulates processes which are associated with tumourigenesis , any mutation or

Table: Role of nibrin in different cancers

alteration in expression will results in tumour proliferation in human being.26-28

DISCUSSION

Nibrin plays a pivotal role in neuronal development in the brain; a mutation in the nibrin gene causes neurodevelopmental defects by increasing the apoptosis results in hampered brain growth.The DNA damage response causes microcephaly and brain tumours, thus playing a major role in embryonic development. 2 9Heterozygous mutation(c.698_701delAACA Nibrin variant) in the nibrin gene can initiate the process of breast cancer formation.30
However different populations have different genetic variants of nibrin but in Turkish population NBN gene 924 T>C, responsible for exacerbating breast cancer in young females Whereas NBN gene 8360 G>C variant and NBN gene 30537 G>C variant are less significant.11 Whereas the increase in expression of nibrin was associated with the poor patient survival rate in a recurrent ovarian cancer trial. Moreover,nibrin act as an independent predictive marker in ovarian cancer patients in different treatment modalities (comparison of Doxorubicin therapy with Trabectin plus therapy) out of 13 DNA damaging proteins the Nibrin expression were significantly raised in Trabectin plus therapy and it was associated with poorer clinical prognosis.31 Heterozygous mutation (657del5 NBS1 allele )in the quality of nibrin gene forms will lead to increase in the mutant form of nibrin protein (NBS1) and has been recognized in both sporadic and familial instances of prostate cancers.32,33 The most prevalent variant of NBN Gene mutation is c.657del5 in hereditary prostate cancers. The risk of prostate cancer development is 4.3 times higher in patients with a known familial cancer history as compared to non-cancer patients in which chances of occurrence of prostate cancer is 2.5%. (34)Researchers had reported that Nibrin ( NBN P6S )plays an important role in lymph node metastasis in gastric carcinoma by increasing the process of lymphangiogenesis intramucosal gastric tumours.35 The mutation of nibrin protein can give rise to fertility defects in human males and premature ovarian failure in humans females.36 but in the mouse, it destroys seminiferous tubules by increasing the process of apoptosis and causes sperm count reduction.Whereas in the female mouse it is responsible for the failure of oocyte
maturation stage in meiosis, oocytes were degenerated and were arrested in diplotene stage of meiosis. 3 7 Squamous cell carcinoma is the most commonly recognised neoplasm of the aerodigestive tract.38 Whereas,
nibrin plays a significant role in DNA repair. However,CMYC(Proto-oncogenes) causes the activation of mutant nibrin formation by increasing the process of tumorigenesis (phosphatidylinositol3-kinase (PI3 K)/Akt pathway.27,28,39,40 Thus in Esophageal Squamous Cell Carcinoma nibrin plays an independent marker for survival and is inversely correlated with the nodal status, in which increased in expression of nibrin is correlated with initial tumour stages and better survival of patients.39
In OSCC and in Non Head and Neck Squamous Cell Carcinoma, overexpression of nibrin acts as an independent
marker of prognosis in advanced cancers.41 In OSCC nibrin overexpression was observed in poorly differentiated oral squamous cell tumour tissue overexpression of Nibrin in early stages of oral cancer had been associated with the
disease recurrence and aggressiveness of cancer therefore it could be used as a prognostic marker for the early-stage
diagnosis of OSCC.8 Nibrin mutation was shown to increase laryngeal cancer formation and secondary tumour formation in lung cancer patients along with head and neck cancer patients in Czech population whereas it does not play a role in the pathogenesis of non-Hodgkin lymphoma.42,43 In medulloblastoma long term hypoxia causes decrease in the level of Nibrin and other members of MRE complex which results in chemotherapy and X-rays resistance.44

CONCLUSION

The clinical findings presented in this review show that increased DNA damage and deficiencies in enzyme systems to repair it, are the key factors implicated in the pathogenesis of cancer formation. Among the various cancers studied in this review, we observed various patterns over and underexpression of Nibrin. This clearly indicates that the expression of Nibrin is important in cancer progression and recurrence. , Nibrin is the first DNA repair gene whose overexpression is capable of transforming and promotes the process of tumorigenesis by the activation of the process of tumourigenesis( phosphoinositol 3 kinase /akt of PI3-) in human cancers Thus we conclude that the role of nibrin still requires a detailed and thorough investigations.8,45

CONFLICT OF INTEREST

None declared

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  1. Lecturer/Mphil trainee, Department of Pathology, Ziauddin College of Dentistry.
  2. Principal, Ziauddin College of Dentistry.
  3. HoD, Associate Professor, Department of Oral Pathology, Ziauddin College of Dentistry.
  4. Mphil trainee, Department of Oral Pathology, Ziauddin College of Dentistry. Lecturer Sir Syed Medical College for Girls.
    Corresponding author: “Dr. Fizza Abidi” < dentistrulz12@gmail.com >

Patterns of Facial Fractures Associated with SoIicio-demographic and Causative Factors: A Multi-Center Analysis from Karachi

 

Beenish Fatima Alam1                                                       BDS, Msc, MFDS RCSED

Sidra Mohiuddin2                                                               BDS, MDS

Salim Hosein3                                                                      MD

Mervyn Hosein4                                                                  FDS RCS, FDS RCSE, FFD RCSI

OBJECTIVE: To assess the association of age, gender, and mechanism of injuries in patients presenting at tertiary care facilities of Karachi, Pakistan.

METHODOLOGY: A retrospective analysis of 1038 patients visiting private and public tertiary care dental hospital was conducted. Data was collected by means of a comprehensive history, clinical examination and radiological investigation. Qualitative variables were calculated as frequencies and percentage whereas means and standard deviation of quantitative variables were analyzed. Association among dependent and independent variables were assessed by Chi square test.

RESULTS: A total of 1038 patients reported, which included 85 % males and 15 % females. Road traffic accidents accounted for 43% of injuries in males and 12% in females and were followed by falls in 15% males and 8% females. Body of mandible was the most frequently affected bone accounting for 32%, while condyle was next commonly involved. Left side of mandible was noted to be more frequently affected. Only 6% of fractures involved the zygomatic region.

CONCLUSION: In this study RTA’s were the most common cause of injuries among males and females in the second and third decades of life while in young children falls predominated. The mandibular body was the most frequently involved site followed by the condyle.

KEY WORDS: Maxillofacial injuries, Road traffic accidents, falls, body of mandible, trauma

HOW TO CITE: Alam BF, Mohiuddin S, Hosein S, Hosein M. Patterns of Facial Fractures Associated with Socio-demographic and Causative Factors: A Multi-Center Analysis from Karachi. J Pak Dent Assoc 2019;28(3):103-107.

DOI: https://doi.org/10.25301/JPDA.283.103

Received: 29 March 2019, Accepted: 17 June 2019

INTRODUCTION

Trauma to the maxillofacial region can cause injuries affecting the craniofacial skin, bones and neurovascular-sensory organs. These occur as consequences of falls, interpersonal violence, accidents or other associated etiological factors.1 The mandible is most commonly affected because of its prominent position on the face.2 Studies have concluded that within the mandible, 36% of fractures involve the condyle and 21% affect the mandibular body. The angle is involved in 20% of cases while parasymphyseal fractures account for 14% and the symphysis, coronoid, ramus and alveolar areas all account for up to 3% each. Within the maxillary bone, Le Fort II fractures were the commonest followed by Le Fort I and Le Fort III.3

The factors associated with maxillofacial traumatic injuries vary considerably from one geographical region to the other. Statistics from developed countries show that physical assault is the most common cause of trauma whereas among developing countries road traffic accidents (RTA) are the leading factor.4,5,6 The WHO has documented that nearly one-third of traumatic injuries reported in developing countries are due to road traffic accidents (RTA) which significantly contribute towards increased mortality rates.7,8 The purpose of the current study was to assess the association of age, gender, and mechanism of injuries in patients presenting at tertiary care facilities of Karachi, Pakistan. Locally reported data have shown that males are more prone to facial injuries during their 2nd and 3rd decades of life with the most common etiologic factor being road traffic accidents (RTA).6,9 Moreover, studies conducted in past focused more upon the relation between different etiological factors and gender; therefore the association between facial injuries with gender, age and mode of injury needs to be addressed. Hence the objective of the current study is to assess the association of age and gender with mode of injury, as well as to analyze the site of injury with respect to age.

METHODOLOGY

This analytical cross sectional study was carried out in tertiary trauma care centers, based on primary data collected by a single examiner over a period of five years. A total of (n=1038) cases were recorded; data collection was based on detailed history, thorough clinical examination as well as radiographic evaluation. Radiographs commonly used were: Orthopantomogram (OPG), Postero-anterior (PA) view of face, lateral view and lateral oblique view for mandibular injuries, with Occipito- Mental (OM /PNS) view used for mid face injuries. Computed Tomography (CT scans) tended to be used for complex and pan facial fractures usually associated with head injuries.

For evaluating dento-alveolar injuries intra oral radiographs were additionally used including periapical and occlusal views, as necessary.

Data was collated regarding age, gender, mode of injury, anatomical location of fracture in mandibular and maxillary bones based on R. Dingman and P. Natvig’s classification10 as well as side of face affected: right, left or bilateral involvement.

Data analysis was performed using SPSS version 21 (Statistical Package of Social Sciences). Qualitative variables were calculated as frequencies and percentage whereas means and standard deviation of quantitative variables were analyzed. Association among dependent and independent variables were assessed by chi square test. Level of significance was kept p<0.05.

RESULTS

A total of n=1038 patients were reported, out of which 85.5% (n=887) were males and 14.5% (n=151) were females. Ages ranged from 02 years to 80 years, with the mean age of 24.65 ±13.76 years. In eighteen percent (n=189) of cases, the ages ranged from of 0-10 years; the peak incidence was in patients with age range of 11 to 30 years that accounted for fifty seven percent (n=593) of cases. However, twenty one percent (n=216) of cases were from age range of 31-50 years, three percent (n=33) from 51 to 70 years and less than one percent (n=07) were of 71 and above.

presented with sports related injuries and three percent (n=34) had industrial traumatic injuries while four percent (n=38) of cases presented with other mode of injury.

Regarding the location of fracture in mandible; the mandibular body was most frequently involved at 32% (n=327) followed by condylar process of mandible at 29% (n=299). The chin region and angle of the mandible were reported to be 18.4% (n=191) and 17% (n=178) respectively while the least involved parts were alveolus 2.6% (n=27) and Pterygoid body 0.1% (01). The left side of the mandible was found to be most frequently involved at thirty eight percent (n=395) while thirty six percent (n=368) and twenty three percent (n=239) of the cases reported with right side and bilateral involvement, respectively.

Only seventeen percent (n=174) maxillary fractures were reported, among which the most common site was the Zygomatic/orbit region 5.8% (n=60) followed by the maxilla body at five percent (n=52). In maxillary fractures 9.5% (n=99) patients were reported with bilateral involvement, 5.6% (n=58) and 5.1% (n=53) with right and left side, respectively. (Table 1) Statistically significant difference was found between gender and cause of injury (p<0.003), with males injured more through road traffic accidents (n=513) f o l l o w e d b y accidental  falls (n=174). Whereas, females  also encountered RTA more frequently.

 

Table 1: Descriptive analysis of the demographic variables, etiology and location of Mandibular & Maxillary fractures along their sites

(Table 2) Statistically From the reported etiology of injury fifty six percent (n=582) were road traffic accidents, twenty two percent (n=224) claimed to have accidental falls, twelve percent (n=122) were victims of assault, four percent of cases (n=38) significant difference was found among gender and location of the fracture in

Table 2: Association of gender and mode of injury

Chi square test, * statistically significant

Table 3: Association of gender and mandibular fractures

Chi square test, * statistically significant

Table 4: Association of age and mode of injury

Chi square test, * statistically significant

mandibular bone (p<0.000), among males, mandibular body (n=280) followed by condylar process (n=255) were the most frequent reported sites. (Table 3)

Statistically significant difference was noted among the age ranges of the study subjects and the cause of the injury (p<0.000). In the age range of 11 to 30 years road traffic accidents (n=365) were more frequently reported. However, histories of accidental fall (n=107) were more common in the age range of ten years and below. (Table 4)

DISCUSSION

The majority of the samples in the current study were adult males, in the second and third decade of life and this was statistically significant. Road traffic accidents are a major cause of injury followed by accidental falls. The latter mode of injury was found to be more common amongst children in the first decade of life. Being most prone to injury the body of mandible was the most commonly affected site, followed by the condyle itself. Zygomatic region was noted to be more likely to be injured followed by trauma to maxillary bone among fractures associated with the mid face.

In the current study, the majority of injuries involved the males; these findings concur with previous studies.11,12,13

The overall male to female ratio was 4:1 which was similar to the findings of other studies.14,15 Furthermore, males in the second and third decades of life were most commonly involved; these findings also were similar to other regionally reported local studies.16,17,18 This may be because men are more freely mobile and involved in outdoor activities as compared to women, particularly in our socio-economic setting, often relying on unsafe modes of transport such as motorcycles, hanging on to buses or jaywalking. Furthermore, in the current study, young children in the one to ten years age group were more prone to injuries caused by accidental falls, and these findings are consistent with other studies.19,20,21 Children of that reported age group are growing up fast and are more liable to injuries while playing; occasionally they fall from beds or slip from parents hands due to inadequate safety measures and carelessness.

In the current study road traffic accidents were found to be a major cause of injury, approximately half of the sample however differs from other studies.22,23 Moreover, statistics from western world have demonstrated physical assault as an important cause of maxillofacial injury.24 RTA’s are more common due to failure to follow safety measures while driving; such as the use of seat belts or wearing of helmets and weaving through traffic by bikers, and also due to poor maintenance of roads. In industrialized countries these basic rules of the road are strictly applied and followed. Injuries due to accidental falls were the next most common cause of injury; this is consistent with the study conducted in India and with previously reported studies.25,26 While child abuse must always be considered in cases of trauma especially those that do not fit described histories and patterns, or when issues of possible negligence of parents and caretakers is involved, the active nature of growing children does tend to make them more accident prone.27

The most common mandibular site of fracture observed in the current study was of the body of mandible followed by the condylar part. Similar finding were reported by previously conducted studies.28,29 Apart from road traffic accidents being more common in our part of the world, high mobility and relative lack of surrounding bony support of the mandibular bone as compared to other facial bones is a contributing factor. However these finding were divergent from the statistics reported from developed countries.30,31,32 In the west, assault was a major risk factor which has been attributed to stressful everyday routines and interpersonal differences along with higher usage of drugs and alcohol in those societies. Strict laws regarding drinking and driving and casual alcohol breath testing by police make RTA’s on this account relatively less common. In the current study, statistically significant association

has been found between gender and mode of injury. Males predominate, due to their aggressive nature as well as more involvement in outdoor activities and freedom of movement, as compared to females in our eastern society. Current study demonstrated RTA as major cause of trauma among males, which can be attributed to improper implementation of traffic rules and regulations, among other reasons. Females reportedly suffered more from falls, some of which could be due to domestic violence which is reportedly more common yet unrecognized within developing countries.33 Location of fracture within the mandible also demonstrates considerable relation with gender. It is seen that body of mandible is the most commonly involved site followed by condyle, due to road traffic accidents and falls, commonly affecting males belonging to second and third decades of life.

Among the maxillary fractures noted in the current study, zygomatic region was the commonest site to be involved and affected by trauma; similar findings were stated by previous studies.34 The subsequent frequently affected sites were the maxillary bone region which coincides with study conducted by previous researchers.35,36,37 Zygomatic bone is a prominent bone of the face and during interpersonal assault is frequently subjected to trauma. The basic protective tendency in the midface area is to turn the face downwards and to the side in order to protect the thinner central naso-orbital structures.38

CONCLUSION

RTA’s are the most common cause of injuries in males and females between the second to third decade with the body of mandible being most frequently involved followed by the condyle. Falls among young children was the primary cause of injury followed by RTA.

RECOMMENDATIONS

It is strongly recommended that road infrastructure needs urgent maintenance to reduce the tendency of sudden braking and evasive driving. Equally, the driving rules and regulations, especially those related to the age of drivers, speed control and the wearing of seat belts and helmets needs to be strongly followed and strict actions needs to be taken against violators. Thirdly, public awareness programs regarding safely measures and precautions needed while driving; and relating to issues of child safety and negligence/ abuse precautions must be widely publicized via the media.

CONFLICT OF INTEREST

None declared

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  1. Assistant Professor & HoD, Department of Oral Biology, Bahria Universtiy Medical and Dental College.
  2. Assistant Professor & HoD, Department of Community & Preventive Dentistry, Ziauddin College of Dentistry,
  3. General Surgeon, Department of M.I.S, General Surgery, University of Nebraska Medical Center,
  4. Dean, Ziauddin College of Dentistry, Ziauddin University
  5. Corresponding author: “Dr. Mervyn Hosein” < mmh5617@gmail.com >