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ISSN : 2278-6686

Issue 1

Volume 1

Jan-March 2016

BANGALORE DENTAL JOURNAL

Official Publication of IDA Bangalore Branch

ISSN : 2278-6686

Issue 4

Volume 3

Dec 2018 - Feb 2019

Intraoral repair techniques for metal ceramic restorations 6

Evaluation of the Pathologic Evidence for Elective Extraction of Asymptomatic Impacted Teeth- An Observational Study 10

Irritational fibroma: A sequalae to luxation injury in 16primary teeth: A case report

3

EDIT

OR

IAL

Review Board

Editorial Board

Associate Editor :Dr. HEMA KN

Dear members,

I am honoured to have been elected as the new editor-in-chief of IDA Bangalore Journal and am thrilled to share my vision for the future of our prestigious E-Journal.My primary goal as editor-in-chief is to ensure that The Journal maintains the highest level of ethical integrity, ensuring consistency and scientific rigor in each of its articles. My desire is for The Journal to continue to excel and insightfully build for the future to provide the greatest venue for sharing outstanding science. I am dedicated to lead the board's mission in providing authors with a productive, fair, and timely review experience.On behalf of IDA Bangalore Branch, I welcome researchers of all specialities in dentistry to contribute their work to our esteemed E-Journal. Best Regards

Editor In ChiefIDA Bangalore Journal

With Warm Regards,

Dr. SANDEEP J NEditor-in-Chief,

IDA BANGALORE

ORAL MEDICINE AND RADIOLOGY Dr.RAMAMURTHY T K Dr.Annaji A G ORAL PATHOLOGY :Dr.JYOTHI ALURDr.SHEETHAL ORAL SURGERY :Dr.SRINIDHIDr.UTKARSH LOKESH

PEDODONTIA :Dr.DHANUDr MADHU K

PERIODONTIA :Dr.VINAY KUMARDr.KISHORE H C

PROSTHODONTIA :Dr.NANDA KISHORE BDr.PREMNATH

COMMUNITY DENTISTRY :Dr.MURALI IYERDr.SUSHI K

CONSERVATIVE :Dr.MEENADr.MADANKUMAR

ORTHODONTIA :Dr.HEMANTHDr.BHARATH REDDY

4

IDA BANGALORE BRANCHLIST OF OFFICE BEARERS FOR THE YEAR 2018 - 19

Hon. Treasurer:Dr Sudarshan Kumar RN

Dr.Tilakraj T NDr.Mahesh Chandra KDr.Annaji A GDr.Kishore H CDr.Ashwathraju

Executive Committee Members:

Representatives to State:

Dr. B T HegdeDr. Dhayakar K VDr. Ulhas N AmasiDr. Murali RDr. Chethan R

Dr. UtkarshLokeshDr. SiddharthDr. JeevanShettyDr. Revankumar JoshiDr. Abhilash P R

President

Dr. Girish SharmaHon. Secretary

Dr Smitha T

President Elect : Dr. Veerendra Kumar BImm. Past President : Dr. Nanda Kishore BVice Presidents : Dr. Madhusudhan Reddy

Dr. Suresh TDr. MGS PrasadDr. Srivastava B K

Hon. Joint Secretary : Dr. VidyaSagar D VHon. Asst. Secretary : Dr. Uma S RHon. Editor : Dr. Sandeep J NChairman CDE : Dr. Prashanth B RChairman CDH : Dr. AkshayShetty

Advisors:

Dr. Sudhakar M CDr. Jagadeesh CDr. Prakash H PDr. SanjayMohanchandraDr. Veerendra Kumar S C

Dr. Prabhuji MLVDr. Sudhindra Kumar NDr. Srinidhi DDr. Ranganath VDr. Narendra Kumar M

Dr. Ramamurthy T KDr. Harish B NDr. ChaitanyaBabuDr. PrafullaThumatiDr. Ravindra C Savadi

Dr.Sanjay Kumar DDr.CharanShettyDr.Ramesh LDr.Sai RameshDr.Sadananda M P

Dr.Madhu KDr.Manjunath V KDr.PremnathDr.MohammedNoamanDr.Raghu T NDr.Rohith S

Dr. Deepak SDr. Harikiran A GDr. SudharshanDr. DeepaK VDr. Satheesha Reddy B HDr. Madan Kumar M

PR

ESID

ENT’

S M

ESSA

GE

President, IDA Bangalore Branch

SEC

RET

AR

Y’S

MES

SAG

E

Dr Smitha THon. Secretary

IDA Bangalore Branch

5

Dr. Girish Sharma

It is with great pride, enthusiasm, and anticipation that I invite you to read the inaugural issue of the IDA BANGALORE DENTAL JOURNAL, a new kind of research journal.

As we look at Journal, it is important to keep in mind that it represents the collective thinking of a group of innovative individuals with whom I am privileged to work. First, we want Journal to be the premiere scientific journal in Dental Sciences. We want it to look different, to be different, to be one journal that, with its related website, will be as dynamic as the work going on in our disciplines, a rarity in academic publishing. Second, we want it to be a vehicle for a new type of conversation about dental practice and its place in the academic review, tenure, promotion, and reward process. That’s a tall order, but with your help we will make it happen.

Over the past six years, having acquired considerable new experience in Indian Dental Association with such experienced and well informed colleagues from all the Dental Colleges , and papers of various qualities covering all fields of dental medicine, I believe this is the proper time to initiate some new activities. Setting a web site is such an activity; I believe quite an important activity, which will add to the Journals wider recognition and, consequently, better and more efficient communication and exchange of scientific ideas. Now, on the web site, the BDJ will be easily found, and I hope that this will enable the BDJ to become a well-known international scientific journal, covering all aspects of Dental Medicine.

Dear members,

It gives me immense pleasure to present to you the first issue of the current edition of BDJ for the year 2018.

It's been a very enriching and memorable journey as President, IDA Bangalore branch, which has given me an opportunity to evolve as a person and to serve our fraternity in my capacity.

I would like to thank all the office bearers of the IDA Bangalore branch and all the people who have supported me through this journey.

I would like to express my heartfelt thanks to Dr. Sandeep JN our editor for his enduring efforts in ensuring the publication of this journal.

Dear respected IDA member,

TREA

SUR

ER M

ESSA

GE

An enormous amount of work has gone into the development of this journal and I believe you will see that effort reflected in this journal and in the impact it will have on the field. It has been an interesting journey, the journey has not been one with a completely charted course. It could not have been, given our time constraints.

Dr Sudarshan Kumar RNHon. Treasurer

IDA Bangalore Branch

Intraoral repair techniques for metal ceramic restorations

Abstract:

Metal ceramics restorations have been widely used because of its strength and superior aesthetic properties. But one of the most common causes of its failures is the chipping of ceramic. If the restoration poses minor fracture or chipping, removal and replacement of entire restoration is not always necessary. It may be desirable to repair such fixed prosthesis to prevent the possibility of destroying the entire restoration or damaging the abutment teeth and to avoid additional laborious procedures and expenses. This article presents various intraoral techniques and methods to repair a fractured metal ceramic restoration.

Keywords: ceramics; composite resins; fracture; intra-oral repair; surface conditioning

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Introduction:

Metal ceramic, all ceramic crowns and fixed partial dentures are widely used in clinical practice because of their high mechanical strength, satisfactory aesthetics and superior biologic properties. Metal ceramic restorations, probably the most frequently

1used, can survive up to twenty five years. However metal ceramic restorations can over a period of time may result in failure. Clinical studies indicate that the prevalence of ceramic fractures ranged between 5

2 and 10% over 10 years of use. Fractures of ceramic can occur due to trauma, acute accidents, chronic habits like bruxism, minute undiagnosed flaws during veneering, contamination in original porcelain fabrication, inadequate tooth preparation, inappropriate coping design and reduction in

.3,4interocclusal space Fractures in the anterior region pose an aesthetic problem, but when they are in the posterior region, chewing function could also be

5 affected. According to the literature, repair methods of the damaged metal ceramic restorations have been classified into two types - the indirect method, and the direct method. Indirect repair is an option that includes repair and restoration in the laboratory while direct repairs include techniques that use composites

6 applied directly to the fractured restoration. Fracture of ceramic is often considered an emergency treatment and the restoration process can present difficult challenges to the dentist. Because of the nature of the ceramic processing, new ceramic cannot

Intraoral repair techniques for metal ceramic restorations

1 2 3 3 3 3Authors: Prema , Sounderraj K , Anu Raveendran , Sreeshma CS , Avinash NT , Abhishekh G

1) Associate Professor2) Professor and Head3) PostgraduateDepartment of Prosthodontics and Implantology, Government Dental College and Research Institute, Bangalore

Corresponding author:Anu Raveendran (Postgraduate)Ph: 91 9605160435Email:[email protected] address: #7, Sriniketan, 2nd Main Road, Ganganagar Extn, Bangalore-560032

5be added to an existing restoration intra-orally. The manual fabrication of metal frameworks and porcelain veneers is time consuming and requires a

7 high level of skill. Intra-oral repair options provide the possibility of repairing the veneer in the patient's mouth, thereby preventing replacement of the complete restoration. Aesthetic and functional repair, wherever possible, has many advantages over time consuming and expensive remakes of crowns or

5 bridges. Removal of existing fixed partial dentures could lead to clinical complications such as deformation of the metal and iatrogenic fracture of the sound tooth tissues that can seriously

8 compromise the longevity of the tooth. Moreover replacement of fixed partial denture is generally a complex and expensive procedure, leading to a considerable increase in chair side time, which is not always well accepted by the patient.

An analysis on the problems associated with fracture of metal ceramic restoration shows that direct intra oral repair has more benefits than an indirect repair.

Materials and methods:

The peer-reviewed literature published in English between 01/01/1995 and 30/12/2018 was electronically searched using PubMed and Google Scholar, followed by manual search of the scientific literature. Multiple key words and their combinations (Metal ceramic Intraoral repair, Metal ceramic fracture, Chipping, Fracture, 'Bonding', and 'Surface

8

7

treatment'), and different search strategies were employed to obtain the potential references for review.

Discussion:

Types of porcelain fractures:91. Based on severity of fracture:

Fracture in the porcelain only without metal exposure, Fracture with both the porcelain and metal exposed, Fracture with substantial metal exposure.

2. Based on treatment need according to severity of the situation:

10A) The Heintz and Rousson classificationGrade 1: Fractures requiring polishing onlyGrade 2: Fractures requiring repairGrade 3: Fractures requiring replacement

11B) Friedman ClassificationStatic Fracture – where a segment of porcelain fractures but remains in place

Cohesive Fracture – fracture occurring within the body of porcelain; also known as chipping fracture

Adhesive fracture – failure of the bonding interface between veneering and core porcelain or between porcelain and metal substrate

Various intraoral repair techniques:The techniques for repair of fractured metal ceramic

12,13restorations include:

(1) rebonding the fractured chip to the fixed restoration,

(2) making a porcelain veneer to bond to the fractured porcelain

(3) using a composite resin to restore the fractured porcelain.

The last method is a simple, reliable and cost-effective, repair technique. The clinical success of the ceramic repair system is almost entirely dependent on the integrity of the bond between the ceramic and the composite resin. This integrity is achieved either by

5chemical or mechanical bonds . Various surface treatments can be performed to improve the bond between ceramic and metal. The most common surface treatments are micromechanical roughening, hydrofluoric acid etching ,airborne particle abrasion with aluminum or with particles modified by silica,

silanization or a combination of a few of these treatments.

Micromechanical roughening

Mechanical retention can be obtained using grooves or undercuts to retain the composite resin to ceramic or metal. Owing to micro leakage and humid intra-oral conditions, this type of repair was considered as an

5interim procedure. It was reported that the use of fine and coarse diamond burs increases crack initiation and propagation through the ceramic which

14could result in failure.

Hydrofluoric acid etching

Hydrofluoric acid etching promotes the dissolution of the ceramic vitreous matrix, forming porosities on the

15treated area, and thus promoting surface roughness. The mechanical imbrications of the repair material onto these irregularities increase the adhesive bonding. The greatest advantage of these systems is

5that chair-side application is very simple. Furthermore the restoration can be re-etched in case of failure without the need for sophisticated laboratory procedures. Etching with 2.5 – 10% HF acid for 60 seconds is the recommended method for the chair side surface preparation of fractured silicate

16ceramics. However, the use of HF acid demands extreme caution as any spills could be hazardous to

17the soft tissues. Hence, despite its effectiveness, hydrofluoric acid should be used sensibly to avoid

4harms to the oral tissue.

Acidulated phosphate fluoride (APF)

Acidulated phosphate fluoride (APF) in a concentration of 1.23% has also been used for surface

18etching. It is safe to the oral tissues but an etching 19

time of at least six minutes is required. It acts by attacking glass probably due to selective release of sodium ions, interrupting the silica network

8. Acidulated phosphate fluoride gel was found to create smooth, homogenous surfaces on the exposed ceramic, whereas hydrofluoric acid produced a

20porous, amorphous surface.

Surface treatment with silica

In this method, reported in the 1970s by Newburg and Pameijer, an increase in bond strength between metal and resin have been reported if the metal is

21pretreated with silica. The silane coupling agents are hybrid inorganic organic bi functional molecules that

BDJ, Dec - Feb 2019, Volume 3, Issue 4

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promote chemical adhesion between organic and 2inorganic structures. This mechanism of action

occurs by silanol group bonds to the vitreous matrix of the ceramic and organo functional group bonds to the organic matrix of the resin material employed. In addition, the silane coupling agents favour the wettability and surface energy of the ceramic surface, increasing the contact area with resin composite, thereby obtaining a durable adhesion between the

22ceramic and the intra-oral repair composite.

Alternatively, alloy primers can create a direct chemical bond between metals and resin, without the need for any silicatization. These primers contain carboxylic or phosphoric acid functional monomers which react with oxides present on the metal surface. Products combining both silane and primers are recommended for enhancing bond strength in the intraoral repair of base metal alloys bonded to ceramic restorations.

Airborne particle abrasion with aluminum oxideOne of the effective surface treatments for repairing fractured metal ceramic restoration is airborne particle abrasion with aluminum oxide. This technique is based on direct sandblasting of the surfaces by an intra-oral device. Air abrasion (or sandblasting) promotes micromechanical retention. It increases surface roughness decreases surface

5 tension thus increasing the adhesive area. A particle size of 50 micron aluminum oxide is usually used to alter the ceramic surface. Air abrasion improves the retention between the metal and resin by cleaning oxides or any greasy materials from metal surfaces, creating very fine roughness enhancing mechanical and chemical bonding between resins and

23metals. One of the major advantages over hydrofluoric acid etching is that air abrasion does not expose patients to the risk of severe acid burns.

A recently introduced air-abrasion technique (CoJet, ESPE) based on tribochemical silica coating provides ultrafine mechanical retention by sandblasting, as well as a chemicophysical bond between the composite resin and the ceramic or metal alloy using a silane coupling agent. The working principle of CoJet is tribochemical application of a silica layer by means of sandblasting. The surfaces are blasted with 30-µm grain size Aluminium oxide modified with silisic acid, CoJet-Sand, with an intraoral sandblaster. The blasting pressure results in the embedding of silica particles in

the metal or ceramic surface, rendering the surface chemically more reactive to resin via silane. Superior bond strengths compared to methods involving the use of silane with aluminum oxide, hydrofluoric acid, or diamond roughening only, is achieved when this

24conservative approach is used.

Lasers Technological developments have resulted in the use of lasers in almost all fields of dentistry. Lasers have also been used as a means of etching the alloy surface. In comparison with air abrasion, alloy treatment with XeCl lasers showed improved bond strengths to

25composite resins whereas treatment with the Er:YAG laser did not yield effective surface roughening

26,27sufficient to promote the metal-resin bond. Madani et al. reported that laser treatment of alloys in conjunction with air-borne particle abrasion yields significantly better bond strengths than laser treatment alone. The various features of lasers like their pain free use, freedom from vibration, low risk of infection, ability to focus on a specific area, thereby preserving neighboring tissues, and reduced application time have increased interest in their use as

27an alternative technique.

Silica lasingSilica lasing an innovative and a newer method to enhance bonding between metal and resin involves coating the metal with an opaque porcelain slurry and

28irradiating it with a laser such as Nd: YAG. In a study conducted by Azam S Madani etal efficiency of silica lasing can be improved by using different types of dental lasers, silica nanoparticles and adding laser

27beam absorber.

Repair with Composite ResinComposite resins are commonly used for the repair of ceramic fractures. If there is a small part missing, composite resins of appropriate shade have been the material of choice for aesthetic appearance and ease of manipulation. To repair an adhesive fracture with composite material, a more opaque shade is selected for the first layers to emulate the dentin and to mask the colour of underlying metal, whereas lighter and more translucent shades are then utilized for

29 restoration. The use of fibre-reinforce composites has been recommended for the repair of metal-ceramic crowns and fixed partial dentures as they offer increased fatigue resistance, thereby increasing

30the longevity of the repair.


9

In order to withstand the functional loads, the bond between the repair material and the restoration must be sufficiently strong. The repair material which ensures this bond should have a minimal coefficient of thermal expansion and minimal polymerization

5 shrinkage. The type of composite resin also affects its bond strength to ceramic. Hybrid composites are usually preferred to microfilled composites because

32of high bond strength and decrease in stress. The problems of wear and surface changes are not related to the repair system but to the use of the microfilled composite resin which could be minimized if a hybrid composite resin is used. It is also recommended to be

32, 33used where fatigue loading is of consideration.

Survival rate of intraoral repairs In a study conducted by Ozcan etal the overall survival rate of intraoral repairs of metal ceramic over a period of 36 months was found to be 89%. 3Another study reported a 97.6% survival rate for metal-ceramic restorations repaired with composite after 3.5 years

34of clinical service.

The oral environment is important for the durability of the repair materials. Water absorption may reduce the mechanical properties of resin-based materials. Dimensional stability or creep properties are of interest because restorations are used in load-bearing areas, where relative deformation could occur under

3a static or intermittent load.

Oral habits of the patient are also an important factor in the success of intraoral repair. Patients who consume more coffee, alcohol and cigarette should be considered as risk patients for discoloration after intraoral repair. Occlusal adjustments if any should be meticulously done as occlusal forces will also

3determine the success of repair.

Conclusion:

Fractures involving the veneering porcelain of metal-ceramic restorations are routinely encountered in dental practice. The decision to repair or replace such a restoration revolves around a number of different factors including time and cost. While replacing the failed restoration may be the ideal treatment, it is not

36always practical. Repair of fractured porcelain should be attempted wherever possible. When attempting to repair a fractured ceramic restoration, it is important to determine the reason for failure and eliminate it, or else the repair will probably fair no better than the

original restoration. The patient has to be informed of the possible risks and alternative solutions. Repairing ceramic restoration fractures with composite resins has some major advantages, as it preserves the main body of the restoration and avoids extra unnecessary cut of the tooth, making the treatment inexpensive and easy when no replacement or fabrication of an

36over-casting is possible.

References:

1. Blatz MB. Long-term clinical success of all-ceramic posterior restorations. Quintessence Int, 2002; 33:415-426

2. Coornaert, j., Adrians, P. & De boever, j. Long-term clinical study of porcelain-fused-to-gold restorations. Journal of Prosthetic Dentistry1984; 51:338.

3. Ozcan M, Niedermeier W. Clinical study on the reasons for and location of failures of metal-ceramic restorations and survival of repairs. Int J Prosthodont. 2002;15:299-302.

4. Haneda IG, Almeida-Junior AA, Fonseca RG, Adabo GL. Intraoral repair in metal-ceramic prosthesis: a clinical report. Revista de Odontologia da Universidade Cidade de São Paulo set-dez 2009:21(3): 282-73

5. Ozcan M. Evaluation of alternative intra-oral repair techniques for fractured ceramic-fused-to-metal restorations. J Oral Rehabil. 2003;30:194-203.

6. Kocaağaoğlu HH. Repair of porcelain restorations: Four case reports. Eur J Prosthodont 2015;3:42-6

7. Freilich, M.A., Karmaker, A.C., Burstone, C.J. & Goldberg, J.Development and clinical applications of a light-polymerized fibre reinforced composite. Journal of Prosthetic Dentistry, 2009;80:311.

8. Reston EG, Filho SC, Arossi G, Cogo RB, Rocha CS, Closs LQ. Repairing ceramic restorations: final solution or alternative procedure? Oper Dent 2008;33:461-466.

9.Chung, K.H. ,Hwang Y.C. Bonding strengths of porcelain repair systems with various surface treatments. Journal of Prosthetic Dentistry, 1997;78:267.

10. Heintze SD, Rousson V. Survival of zirconia- and metal-supported fixed dental prostheses: a systematic review. Int J Prosthodont. 2010;23(6):493-502.

11. Friedman M. A 15-Year Review of porcelain veneer failure - a clinician's observations. Compend Contin Educ Dent 1998;19:625-8.

12.Rada, R.E. Intraoral repair of metal ceramic restorations. J. Prosthet. Dent., 1991; 65: 348 350.


13. Newburg, R. and Pameijer, C.H. Composite resins bonded to porcelain with silane solution. J. Am. Dent. Assoc., 1978; 96: 288–291.

14. Wood, M., Litkowski, L.J., Thompson, V.P. & Church, T. Repair of porcelain ⁄ metal restoration with resin bonded overcasting. Journal of Esthetic Dentistry,192; 4, 110.

15. Thurmond JW, Barkmeier WW, Wilwerding TM.Effect of porcelain surface treatments on bond strengths of composite resin bonded to porcelain. J Prosthet Dent. 1994 Oct; 72(4): 355-9.

16. Kimmich M, Stappert CF. Intraoral treatment of veneering porcelain chipping of fixed dental restorations: a review and clinical application.J Am Dent Assoc. 2013;144(1):31-44.

17. Özcan M, Allahbeickaraghi A, Dundar M. Possible hazardous effects of hydrofluoric acid and recommendations for treatment approach:a review. Clin Oral Investig. 2012;16(1):15-23.

18. Tian T, Tsoi JK-H, Matinlinna JP, Burrow MF. Aspects of bonding between resin luting cements and glass ceramic materials. Dental Materials. 2014;30(7):147-62

19. Kukiattrakoon B, Thammasitboon K. Optimal acidulated phosphate fluoride gel etching time for surface treatment of feldspathic porcelain: on shear bond strength to resin composite. European Journal of Dentistry. 2012;6(1):63-9.

20. Tylka, D.F., Stewart, G.P. Comparison of acidulated phosphate fluoride gel and hydrofluoric acid etchants for porcelain-composite repair. The Journal of prosthetic dentistry. 1994

21. Newburg R, Pameijer CH. Composite resin bonded to porcelain with silane solution. I Am Dent Assoc 1978;96:288-291.

22. R Mutlu Özcan, Cláudia Ângela Maziero Volpato. Intra-oral repair technique for ceramic fracture using direct resin composite Italian Journal of Dental Medicine 2016; 1:67-70

23. Yanikoğlu, Nuran. The repair methods for fractured metal-porcelain restorations: a review of the literature. The European journal of prosthodontics and restorative dentistry. 2005;12:161-5.

24. Özcan, M. The use of chairside silica coating for different dental applications. A clinical report. J. Prosthet. Dent., 2002; 87: 469–472.

25. Murray AK, Attrill DC, Dickinson MR. The effects of XeCl laser etchingof Ni-Cr alloy on bond strengths to composite resin: a comparison with sandblasting procedures. Dent Mater. 2005;21(6):538-44.

26. Kunt GE, Guler AU, Ceylan G, Duran I, Ozkan P, Kirtiloglu T. Effects of Er:YAG laser treatments on surface roughness of base metal alloys. Lasers Med Sci. 2012;27(1):47-51

27. Madani AS, Astaneh PA, Nakhaei M, Bagheri HG, Moosavi H, Alavi S, et al. Effectiveness of silica-lasing method on the bond strength of composite resin repair to Ni-Cr alloy. J Prosthodont. 2015;24(3):225-32

28. Sadat Madani A, Astaneh PA, Shahabi S, Nakhaei MR, Bagheri HG, Chiniforush N. Influence of different power outputs of intraoral Nd:YAG laser on shear bond strength of a resin cement to nickel chromium dental alloy. Lasers Med Sci. 2013;28(1):229-34.

29. Raposo LH, Neiva NA, da Silva GR, Carlo HL, da Mota AS, do Prado CJ, et al. Ceramic restoration repair: report of two cases. J Appl Oral Sci.2009;17(2):140-4.

30. Özcan M, van der Sleen JM, Kurunmaki H, Vallittu PK. Comparison of repair methods for ceramic-fused-to-metal crowns. J Prosthodont. 2006;15(5):283-8.

31. Stangel I, Nathanson D, Hsu CS. Shear strength of the composite bond to etched porcelain. J Dent Res 1987;66:1460-5.

32. Creugers NH, Snoek PA, Käyser AF. An experimental porcelain repair system evaluated under controlled clinical conditions. J Prosthet Dent 1992 Nov;68(5):724-7.

33. Llobell A, Nicholls JI, Kois JC, Daly CH. Fatigue life of porcelain repair systems. Int J Prosthodont 1992;5:205-13.

34. Özcan M. Longevity of repaired composite and metal-ceramic restorations: 3.5-year clinical study. 2006

35. Aslam, Ayesha & Hammad Hassan, Syed & Nayyer, Maleeha & Ahmed, Bilal. Intra-oral Repair Protocols for Fractured Metal-Ceramic Restorations - Literature Review. South African dental journal. 2018:73

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ABSTRACT

AIM- The prophylactic removal of lower third molars has been a point of contention in the field of oral and maxillofacial surgery as no clear cut guidelines exist regarding the removal of such teeth which are often the source of odontogenic pathology and it continues to remain in the grey area till date. The aim of this study is to determine whether the asymptomatic impacted third molars required removal or not based on the histopathological changes associated with dental follicle of such teeth.

METHODOLOGY- Two hundred pericoronal tissues were obtained from patients in the age group of 16-50years. The impacted tooth was removed surgically and after the extraction, the associated soft tissue was delivered either separately or attached to the tooth. The associated soft tissue was kept in 10% neutral buffered formalin and sent for histopathologic evaluation.

RESULTS- The study consisted of 200 pericoronal tissues. 91% of the samples were normal dental follicles and 3.5% of the samples were associated with histopathologic changes. 5.5% of the samples were insufficient and could not be evaluated histopathologically.

CONCLUSION- The incidence of pathological changes associated with impacted teeth was statistically insignificant. The routine extraction of asymptomatic impacted teeth cannot be justified but it mandates histopathologic examination of the follicular tissue of the extracted impacted teeth.

KEY WORDS- impacted teeth, lower third molar, dental follicle, cysts and tumours

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1 2 3 4 5Authors: Poorvi A Ghanti , Satish Kumaran P , Anuradha V , Manikandan G , Preeti Satish

1. Dr. Poorvi A. Ghanti- Lecturer, Department of Oral and Maxillofacial Surgery, KLE's V K Institute of Dental Sciences, Nehru Nagar, Belagavi, Karnataka – 590010. Email: [email protected]

2. Dr. Satish Kumaran P- Reader, Department of Oral and Maxillofacial Surgery, M. R. Ambedkar Dental College and Hospital, 1/36 Cline Road, Balaji Layout, Cooke Town, Bengaluru, Karnataka- 560 004, Email: [email protected]

3. Dr. Anuradha V – HOD and Professor, Department of Oral and Maxillofacial Surgery, M. R. Ambedkar Dental College and Hospital, 1/36 Cline Road, Balaji Layout, Cooke Town, Bengaluru, Karnataka- 560 004, Email: [email protected]

4. Dr. G. Manikandan – Assistant Professor, Dept of Dentistry, Shri Sathya Sai Medical College and Research Institute, Ammapettai village, Kancheepuram district. Sri Balaji Vidyapeeth. Email: [email protected].

5. Dr. Preeti Satish – Senior Lecturer, Department of Oral and Maxillofacial Surgery, M. R. Ambedkar Dental College and Hospital, 1/36 Cline Road, Balaji Layout, Cooke Town, Bengaluru, Karnataka – 560 004. Email: [email protected]

Evaluation of the Pathologic Evidence for Elective Extraction of

Asymptomatic Impacted Teeth- An Observational Study

1. INTRODUCTION

Dental follicle arises from the odontogenic ectomesenchyme part of the tooth bud and helps in the formation of the alveolar bone, cementum and the periodontal ligament along with its important

[1]roles during the tooth development and eruption.

Pericoronal follicle or sac is the coronal part of the follicle seen attached to the unerupted or impacted teeth. On intraoral periapical radiograph, it appears as a pericoronal radiolucency generally measuring less than 0.5 cm thick. These odontogenic residues later serve as the origin of pathologies of the dental follicle of impacted teeth, the risks of which correspondingly

[1]increase with the degree of tooth impactions. Even

though removal of the impacted tooth is the most commonly performed oral surgical procedure, many oral surgeons still face ambiguity regarding its

[2,3]removal especially when it is asymptomatic.

However, the current anecdotal evidence suggests that prophylactic removal of third molars is a universally practiced procedure. It is often justified on the basis that the third molars are considered to be vestigial organs, have a propensity for the development of cysts and tumours, increase the risk of mandibular angle fracture as well as difficulty of surgery with age (increased presence of co- morbidities with increased age, reduced healing

[4]potential to surgical insult etc.). Hence, the aim of

12

this study was to evaluate the histopathological changes associated with dental follicle of an impacted tooth and the pathological evidence for the extraction of impacted teeth.

2. MATERIALS AND METHODS

The study was conducted on patients who were referred to the Department of Oral and Maxillofacial Surgery, M. R. Ambedkar Dental College and Hospital, Bengaluru for treatment other than the removal of impacted tooth during the duration of November 2015 to June 2017. Inclusion criteria were patients in the age group of 16-50 years, evidence of pericoronal radiolucency associated with an impacted tooth on an intraoral periapical radiograph or an orthopantomo-graph. Patients with systemic disorders or those presenting with pericoronitis or other signs of infection of the third molar tooth were excluded from the study. Using convenience sampling, the sample size considered was 200. The procedure was carried out after taking written informed consent of the patients and was in accordance with the ethical standards of the institution.

2.1 METHODOLOGY

The impacted tooth was removed surgically under local anaesthesia (2% lignocaine with 1:80000 adrenaline). Standard surgical techniques were used. The procedure involved raising a mucoperiosteal flap, bone guttering and sectioning of the tooth as and when necessary with surgical drills and burs, delivering the tooth and the associated soft tissue either attached or separately using elevators, curettage and toileting of the socket followed by suturing of the flap. Standard post -operative instructions were given to the patient. The specimen was kept in 10% neutral buffered formalin and sent for histopathologic evaluation. The fixed specimens were processed in buffered alcohol. Then they were embedded in paraffin wax and sliced into thin sections (5 microns) using a microtome. These were then mounted onto slides and stained using standard haematoxylin and eosin stains. All the histologic specimens were examined by one oral pathologist.

3. RESULTS

Data was entered in MS Excel and Statistical analysis was done using Spss version 20. Frequency and percentages were used for descriptive analysis and Chi square and Fischer's exact test were used for

finding associations The level of significance (P- value) was set at P< 0.05.

Out of 200 patients, 17 were aged below 20 yrs, 134 were between the age group of 21- 30yrs, 46 in 31-40 yrs and 3 patients were above 40 yrs of age. The study sample consisted of 102 male patients and 98 female patients. (Figure 1).

Number of samples from third quadrant were 114 and 86 were from fourth quadrant. Histopathology reports revealed 182 normal follicular tissue, 3 dentigerous cysts and 1 keratocystic odontogenic tumour, 2 ameloblastomas, 1 calcifying epithelial odontogenic tumour and 11 samples were insufficient. (Figure 2)

Left sided third molars (71.1%) show higher incidence of impaction than the right sided third molars (61.6%) in the age group ranging from 21-30yrs. Higher incidence of impaction of teeth on right side (52.3%) than on left side (46.5%) were seen in females and in males, incidence of impacted teeth were higher on left side (53.5%) than the right side (47.7%). The number of dental follicles and the incidence of pathologies were found to be higher in patients between 21- 30 years of age (Table 1). Higher incidence of pathologic changes is seen in males (4.9%) than females (2.0%) (Table 2). Marginally higher incidence of pathology is seen in impacted teeth on left side (3.5%) than right side (3.4%).

4. DISCUSSION

The third molars most often fail to erupt in the oral cavity or are found in aberrant positions considering their timing of eruption, highly variable tooth morphology and genetics. And if they do, are found in aberrant positions. Disimpaction of such teeth constitutes one of the most widespread and routinely performed minor oral surgical procedures. The diseased impacted third molars follow the obvious management protocol i.e., surgical extraction but there is no testimony to the fate of the seemingly innocuous or rather asymptomatic impacted third

[5]molars. Also, not much information is available on pathological changes seen in the pericoronal soft tissue since these tissues are often discarded or destroyed during the procedure rather than being forwarded for histopathological examination.

In this study, highest number of impacted teeth were found in the age group of 21-30yrs (67%) which is

.


13

[6] similar to that reported by Marques et al (70%) and

[7] Chu et al (55.1%). Also, males in the current study showed a higher incidence of impacted teeth than males – 51% and 49% respectively, which is similar to study result by

[8] Mitra et al (64.5% males and 35.5% females). Venta [9] [10]

et al and Qirreish reported that more females than males reported with impacted third molars contrary to our findings. However, a Nigerian study reported equal incidence of impacted third molars

[11]with a ratio of 1:1.

This study found higher incidence of impacted teeth on left side (57%) than on the right side (43%). This distribution compared favourably with the results obtained by an Israel study where the prevalence of third molar impaction was 47.8% on left side and

[12] 52.2% on right side. But Pillai et al reported 50.28% of impacted teeth on right side and 49.71% on left side and they concluded that there was no significant

[13]difference in occurrence in either side of the jaw.

91% of our samples were found to be normal dental follicles whereas only 3.5% were associated with histopathologic changes. This is consistent with results reported by Guven et al. Their study showed

[14] the incidence of cysts and tumours to be 2.31% . 11 specimens in this study were found to be insufficient for histopathologic evaluation and hence, were excluded from the analysis. Literature search showed

[13]varied figures- Lysell and Rohlin and Nordenam A. [15]et al reported prevalence less than <3% and 4.5%

respectively. Eliasson et al in their study found that 59 out of 734 impacted third molars i.e, 8% were

[16]associated with pathologic changes , Mourshed

[17] [18]reported 1.44%, and Dachi and Howell 11% which were found contradictory to our findings.

On comparing the distribution of impacted tooth based on the age group, higher incidence of impaction was found in left side of the jaw (71.1%) in 21- 30 yrs age group. However, this finding was not significant statistically. There was no difference between the gender and distribution of the impacted tooth according to the side. No data was found which compared these variables.

The present study showed very low incidence of pathologic lesions with 3 (1.5%) dentigerous cysts, 1 (0.5%) keratocystic odontogenic tumour, 2 (1%) ameloblastomas and 1 (0.5%) calcifying epithelial

odontogenic tumour. These results were [19]contradictory to the ones reported by Curran et al.

they found among 2646 pericoronal lesions, 673 (28.4%) were dentigerous cysts, 71 (2.68%) keratocystic odontogenic tumour, 13 (0.5%) ameloblastomas and 4 calcifying epithelial o d o nto ge n i c t u m o u rs . T h e i n c i d e n c e o f ameloblastoma, keratocystic odontogenic tumour

[20]and dentigerous cyst as reported by Weir et al was 2%, 1% and 4.2% respectively. The incidence of these lesions in the present study is in line with these figures.

Histopathologic diagnosis of cystic changes as related to gender showed male predominance (4.9%) in our study. This is similar to the observation reported by

[21] [22] Baykul et al (2005) and Daley and Wysocki (1995). There was no difference in the incidence of occurrence of lesions associated with impacted teeth on either side of the jaws (3.5% on left and 3.4% on right). This finding was found out to be statistically insignificant. On literature search, no data were reported on distribution of types of lesions by side of the impacted teeth involved.

5. CONCLUSION

This study suggests that the incidence of impaction and more importantly the pathological changes associated with it seem to be quite less. Though the incidence of positive pathological changes (of odontogenic origin) is statistically not significant, their presence and the co- morbidity associated with such pathological follicles (some of which are aggressive in nature, though benign) suggest that even though the routine extraction of impacted third molars cannot be viewed as a mandatory elective procedure, histopathological examination of the follicles of extracted wisdom teeth should be mandatory to rule out the presence of pathological manifestations.\

6. FUNDING

This study did not receive any specific grant from funding agencies in the public or commercial sectors.\

7.ACKNOWLEDGEMENT

We sincerely thank Dr. Lalitha J. Thambiah, Professor and HOD, Department of Oral and Maxillofacial Pathology and Microbiology, M. R. Ambedkar Dental College and Hospital, Bengaluru for her valuable assistance towards this study.


14

8. CONFLICT OF INTEREST

None

9. FIGURES AND TABLES:

Comparison of HP diagnosis of the dental follicle obtained from Impacted teeth based on the

participants' age group using Fisher exact test

Age

Group

Dental

Follicle

Dentigerous

Cyst

KOT

Ameloblast

oma CEOTFisher exact

value

P-

Valuen

%

n

%

n

%

n % n %

≤ 20 yrs

17

9.3%

0

0.0%

0

0.0%

0 0.00% 0 0.00%

14.197 0.781

21 - 30

yrs

12

1

66.5

% 1 33.3% 1

100.0

% 2

100.00

% 1

100.0

0%

31 - 40

yrs 41

22.5

% 2 66.7% 0 0.0% 0 0.00% 0 0.00%

> 40 yrs 3 1.7% 0 0.0% 0 0.0% 0 0.00% 0 0.00%

Total

18

2

100

% 3 100% 1 100% 2 100% 1 100%

Comparison of HP diagnosis of the dental follicle obtained from Impacted teeth based on the

participants' gender using Fisher Exact test

Gend

er

Dental

Follicle

Dentigerous

Cyst

KOT

Ameloblasto

ma CEOTFisher exact

value

P-

Valuen

%

n

%

n

%

n % %

Males 94

51.6

% 2 66.7% 1

100.0

% 1 50% 1

100.0

0%

2.302 1Femal

es 88

48.4

% 1 33.3% 0 0.0% 1 50% 0 0.00%

Total

18

2 100% 3 100% 1 100% 2 100% 1

100.0

0%

DENTIGEROUS CYST

PLATE 1:

PLATE 2: KERATOCYSTIC ODONTOGENIC TUMOUR


15

CORRESPONDING AUTHOR:Dr. Preeti Satish, Senior Lecturer, Department of Oral and Maxillofacial Surgery, M. R. Ambedkar Dental College and Hospital,1/36, Cline road, Balaji Layout, Cooke Town,Bengaluru, Karnataka- 560 004Email address- [email protected]

REFERENCES

1. Villalba L, Stolbizer F, Blasco F, Maurino NR, Piloni

JM, Keszler A. Pericoronal follicles of asymptomatic

impacted teeth: A radiographic, histomorphologic

and immunohistochemical study. Int J Dent.

2012:1-6

2. Knutsson K, et al. Pathosis associated with

mandibular third molars subjected to removal. Oral

Surg Oral Med Oral Pathol Oral Radiol Endod.

1996;82:10-7

3. Siddiqui SR, Agrawal S, Monga HS, Gaur A.

Prophylactic removal of the third molars: Justified

or not. J Int Oral Health. 2015; 7(11):132-35

4. Mercier P, Precious D. Risks and benefits of removal

of impacted third molars. A critical review of the

literature. J Oral Maxillofac Surg. 1992;21:17-27

5. Hill CM. Removal of asymptomatic third molars: An

opposing view. J Oral Maxi l lofac Surg.

2006;64:1816-20

6. Rafetto LK. Removal of asymptomatic third molars:

A supporting view. J Oral Maxillofac Surg.

2006;64:1811-15

7. Marques NA, Algarra AE, Borgarello QM, Aytes BL,

Escoda GC. Factors influencing the prophylactic

removal of asymptomatic impacted lower third

molars. Int J Oral Maxillofac Surg. 2008;37:29-35

8. Chu FCS, Li TKL, Lui VKB, Newsome PRH, Chow RLK,

Cheung LK. Prevalence of impacted teeth and

associated pathologies- A radiographic study of the

Hong Kong Chinese population. Hong Kong Med J.

2003;9:158-63

9. Mitra R, Prajapati VK, Vinayak KM, Nath S, Sharma

N. Prevalence of mandibular third molar impaction.

Int J Contempor Med Res. Sept 2016;3(9):2625-6

10. Venta I, Turtula L, Ylipaavalniemmi P. Radiographic

follow-up of impacted third molars from age 20 to

30 years. Int J Oral Maxillofac Surg. 2001;30:54-60.

11. Qirreish E J. Radiographic profile of symptomatic

impacted mandibular third molars in the Western

Cape, South Africa. Masters degree dissertation.

Western Cape: University of Western Cape. 2005

12. Muhamad AH, Nezar W. Prevalence of impacted

mandibular third molars in population of Arab

Israeli: A retrospective study. IOSR J Dent Med Sci

2016;15(1):80-9

13. Pillai AK, Thomas S, Paul G, Singh SK, Moghe

Swapnil. Incidence of impacted third molars: A

radiographic study in People's hospital in Bhopal,

India. J Oral Bio Craniofac Res 2014;4:76-81

14. Glosser JW, Campbell JH. Pathologic changes in soft

tissues associated with radiographically 'normal'

third molar impactions. Br J Oral Maxillofac Surg.

1999;37(4):259-60

15. Lysell L, Rohlin M. A study of indications used for

removal of the mandibular third molar. Int J Oral

Maxillofac Surg 1988;17:161-4

16. Nordenram A, Hultin M, Kjellman O, Ramstrom G.

Indication for surgical removal of third molars-

study of 2630 cases. Swed Dent J 1987;11:23-9

17. MOURSHED FA. Roentgenographic study in

detecting dentigerous cysts in the early stages. Oral

Surg 1964; 18: 54-61.

18. DACHI SF, HOWELL FV. A survey of 3,874 routine full

mouth radiographs. II: A study of impacted teeth.

Oral Surg 1961;14:1165-9.

19. Adelsperger J, Campbell JH, Coates DB, Summerlin

DJ, Tomich CE. Early soft tissue pathosis associated

with impacted third molars without pericoronal

radiolucency. Oral Surg Oral Med Oral Pathol Oral

Radiol Endod. 2000;89:402-6

20. Eliasson S, Heimdahl A, Nordenram A. Pathological

changes related to long term impaction of third

molars- A radiographic study. Int J Oral Maxillofac

Surg 1989;18:210-2

21. Weir JC, Davenport WD, Skinner RL. A diagnostic

and epidemiologic survey of 15,783 oral lesions. J

Am Dent Assoc 1987;115:439-41

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Pathol Oral Radiol Endod 2005;99:542-5


Abstract:

Oral benign lesions in children presents a challenge in its diagnosis and management. Irritational fibroma is one of the benign lesions that occur mostly in the buccal mucosa in the line of occlusion and second most common site is the maxillary anterior gingiva and it is fairly rare in children. This paper aims to present a case of irritational fibroma of gingiva in a 7-year female patient as a sequalae to irritation following trauma to primary teeth and the use of laser as a modality to excise the tissue.

Key words: Irritational fibroma, luxation injury, Laser excisional biopsy

Authors: Dr. Sankriti A M

16

Irritational fibroma: A sequalae to luxation injury in primary teeth: A case report

INTRODUCTION

An oral fibroma is a common -like reaction to persistent long-standing irritation in the mouth. It is also known as a fibroma, intraoral fibrous , fibrous or oral polyp. Fibromas are considered the most common benign soft tissue growth in the oral cavity, derived from fibrous connective tissues. [1] Irritational fibromas are fairly less in prevalent in children. We present here a rare case were irritational fibroma developed as a result of luxation injury to primary teeth and the advantageous of using soft tissue laser excision in children.

A 7-year-old female patient reported to the Department of Pediatric and Preventive Dentistry, Vokkaligara Sangha Dental College and Hospital, Bangalore, with the complaint of swelling in the upper front tooth region, for 2 months. History of presenting illness revealed that pain was present for last 3 days, the pain was mild to moderate, intermittent and occurred on eating. The swelling was small initially and grew slowly to the present size. The father gave a history of a fall about a year back, no treatment was given. Her past medical and drug history were not significant. No significant extra oral findings. On intra oral soft tissue examination, a solitary gingival growth was evident with respect to 61, pink in colour, roughly oval about 1mm x 2 mm with overlying smooth surface. Surrounding mucosa was is normal and borders well defined [fig 1]. On palpation all inspector findings were confirmed, the growth was non tender, firm in consistency, mobile and also showed a sessile base towards the vestibule and under the growth, the exposed root of 61 was evident. Hard tissue examination revealed normal compliment of teeth and early childhood caries. 61 crown was lingually

benign scar

traumatic focalhyperplasia nodule

CASE REPORT:

displaced and was blackish brown in colour, with root tip poking out of the gums [fig 2]. Not tender on percussion. Based on history and clinical examination a provisional diagnosis of localised gingival epulis secondary to trauma was made. Differential diagnosis was irritational fibroma.

IOPAR showed no hard tissue lesion and normal 21. The treatment planned was excision of the growth followed by extraction of 61. Informed consent was obtained and the 61 was extracted under local anaesthesia followed by excision of the lesion using laser [fig 3]. The specimen was then sent for histological examination. The histological examination revealed the presence of hyper parakeratinized stratified squamous epithelium and connective tissue. The epithelium was hyperplastic with elongated rete ridges and there was a presence of chronic inflammatory cell infiltrate composed of plasma cells and lymphocytes which was suggestive of irritational fibroma. The healing after 2 weeks was uneventful [fig 4] and the child is currently undergoing comprehensive full mouth rehabilitation.

sharp tooth edges, or other oral prostheses, trauma, lip/cheek biting, irregular denture borders rather than being a true neoplasm. [3] It develops frequently between second and fourth decades of life. The high female predilection and a peak occurrence in the

DISCUSSION:

Traumatic or irritation fibroma is the healed end product of the inflammatory hyperplastic lesion which can occur at any age from almost any soft-tissue site, tongue, gingiva, and buccal mucosa being the most common. It is usually characterized by a slow, painless growth accumulated over a period of months or years. [2]. The etiological factors for these lesions can be imputed to the irritants like plaque, calculus, overhanging margins and restorations,

17

second decade of life suggested hormonal influences. There are very few reported cases of fibroma in children due to traumatic reasons. In our case the trauma resulted in the primary incisor to subluxate in a way that there was a lingual inclination of the crown and a buccal inclination of the root. This led to the root tip being exposed and the sharp tip caused continuous irritation of the gingival tissue and thus lead to formation of irritational fibroma. The usual modalities of treatment for oral soft tissue benign lesion have been scalpel excision, electrocautery or cryotherapy. [4] Lasers have an advantage of clear surgical field offering better visualization, faster healing, less postoperative healing and better patient acceptance, especially in children. [5]. It is important to submit the excised tissue for microscopic examination because other benign or malignant tumors can also mimic the clinical appearance of a fibroma. [6]

CONCLUSION:

Irritational fibroma is one of the most common oral soft -tissue lesion which can be confused with other similar entities such as peripheral ossifying fibroma, peripheral giant-cell granuloma. Therefore, thorough history, clinical, radiological, and histological examination should be carried out to rule out differentials. Advances in dentistry, like the soft tissue laser has made excisional biopsy of such lesions, painless, swift and non-anxiety provoking. Hence making it an ideal choice for excisional biopsy in children. Any trauma to the primary dentition should not be overlooked and regular monitoring for all kinds of traumatic injuries to teeth is mandatory.

REFERENCES:

1. Esmeili T, Lozada-Nur F, Epstein J. Common benign oral soft tissue masses. Dental Clinics of North America 2005; 49(1): 223– 240

2. Wood NK, Goaz PW. Differential Diagnosis of Oral and Maxillofacial Lesions. 5th ed. Missouri: Mosby; 2006. p. 136-8.

3. Nartey NO., et al. “Localized inflammatory hyperplasia of the oral cavity: clinico-pathological study of 164 cases”. Saudi Dental Journal 6.3 (1994): 145-150.

4. GH. Mohd. Mir, K.P. Singh, Sachin Gupta, Amit Manhas , Ajaz Ahmed Malik , Parmod Kalsotra Oral Soft Tissue Benign Lesions-Carbon Dioxide Laser as a Surgical Tool. International Journal of Contemporary Medical Research; 2017,4(1):205-07

5. Kirti Chawla, Arundeep Kaur Lamba, Farrukh Faraz, Shruti Tandon, Diode laser for excisional biopsy of peripheral ossifying fibroma. Dent Res J 2014, jul-aug; 11(4):525-530.

6. Halim DS, Pohchi A, Pang EE. The prevalence of fibroma in oral mucosa among patient attending USM dental clinic year 20062010. Indonesian J Dent Res 2010;1: 61-6.


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