there are few endodontic materials , which when used injudiciously can harm the surrounding hard and soft tissues . for instance improper use of vital and non - vital bleaching agents , sodium hypochlorite , hydrogen peroxide and paraformaldehyde can be damaging to the hard and/or soft tissues surrounding . this is a case report of a 23-year - old male patient who landed up with interdental bone necrosis because of improper use of endodontic medicaments . a 23-year - old systemically healthy patient reported to the department of endodontics with the chief complaint of constant throbbing and radiating type of pain in his right upper back tooth . clinical examination of chief complaint site revealed deep mesioocclusal class ii deep dental caries in relation with upper right first molar . after 2 weeks of successful endodontic treatment , patient again reported back to the endodontics department with the complaint of mesio - proximal food lodgment and localized dull pain with the same . patient was referred to department of periodontology to address patient s complaints and further needful treatment . clinically in the chief complaint site , there was recession of mesial interdental papilla between first molar and second premolar and 5 mm exposure of white bare interproximal bone was noted ( figure 1 ) . on probing haziness of interdental bony trabeculae and alveolar bone crestal changes were observed on the radiograph . the possible explanation for localized pathological interdental bone necrosis was because of leaching of devitalizing intracanal medicaments into the interproximal periodontal structures through damaged mesial wall of tooth . necessary pre - operative blood investigations advised , which involved hemoglobin% , computed tomography , blunt trauma , hepatitis b surface antigen and tridot . ( figures 2 and 3 ) and surgical site accessed and white bare alveolar bone of 5 mm by 3 mm dimensions ( figure 4 ) was found loosely attached to the underlying healthy bone . necrotic bone sequestrum was gently removed , and underlying concave osseous defect was thoroughly debrided and alloplast hydroxyappatite bone graft material was placed and the flap was sutured with 3 - 0 mm black mersilk suture . after 1 week during suture removal there was no evidence of any uneventful changes ( figures 5 and 6 ) . mesioproximal papillary recession was quite evident , so necessary interdental oral hygiene with interdental brush was strongly advised to maintain plaque free environment . after 3 weeks of adequate healing and monitoring patient was referred to department of prosthodontics for placement of crown . management of carious tooth structure matters a lot during endodontic treatment . removal of soft caries , unsupported enamel rods , rubber dam isolation and building lost walls of the tooth is of vital importance to prevent seepage of intracanal medicaments into surrounding periodontal structures and subsequent associated soft and/or hard tissue changes . paraformaldehyde containing products are very commonly used.1 - 3 paraformaldehyde which is used as an intracanal medicament is a fixative and a strong disinfectant.4 paraformaldehyde when placed in contact with the tissues is extremely toxic . paraformaldehyde and sodium hypochlorite as intracanal medicaments are potentially quite caustic to create soft tissue and/or hard tissue necrosis . when in contact with vital tissue , it causes hemolysis , ulceration , and damages endothelial and fibroblast cells.5,6 careful manipulation of intracanal medicaments is mandatory to prevent iatrogenic injuries . kishore reviewed the literature concerning oral tissue complications during endodontic irrigation , the etiology , symptomatology and management of complications during root canal irrigation.7 hlsmann and hahn reviewed the literature concerning the etiology , symptomatology and therapy of complications during root canal irrigation . clinical symptoms are discussed , as well as preventive and therapeutic considerations.8 in this case , the possible explanation for the localized necrosis of alveolar bone is because of seepage of intracanal medicaments into the interproximal periodontal structures through damaged mesial wall of tooth . so building lost walls of tooth is of paramount in such clinical situations so that operator can totally restrict the intracanal medicaments within the root canals . during isolation using rubber dam operator has to take adequate care , while punching right size holes . a large size hole punched on the rubber dam will fit loosely around the tooth , and there is a possibility of seepage of intracanal medicaments intra operatively . this report presented a case of localized alveolar bone necrosis which is an iatrogenic damage occurred because of improper use of intracanal medicaments and improper management of carious tooth structure . iatrogenic damage to dental hard and soft tissues because of improper use of intracanal medicaments is totally preventable . adequate knowledge about harmful effects of the intracanal medicaments and careful execution of clinical procedures are must to avoid such untoward events .
restorative dentistry involves use of various intracoronal and intracanal medicaments . 
 commonly used endodontic medicaments include paraformaldehyde , sodium hypochlorite and hydrogen peroxide . 
 these agents are caustic and in higher and in inappropriate concentrations can cause immediate damage to the surrounding hard and/or soft tissues . 
 proper knowledge of such agents and careful use of such intracanal medicaments is necessary to avoid iatrogenic injuries . 
 this report presented a case of localized alveolar bone necrosis which is an iatrogenic damage occurred because of improper use of intracanal medicaments and improper management of carious tooth structure . 
 subsequent management of the case is also discussed in this case report .