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prosthodontic rehabilitation of oral cancer patients with osseointegrated dental implants may considerably improve their contentment , happiness , physical and mental health , and also enhances quality - of - life .
oral and oropharyngeal cancer accounts for 3 - 5% of all cancer occurring in the body .
approximately , 50% of these are located in the oral cavity , and more than 90% are squamous cell in origin .
dependent upon clinical stage of oral cancer , surgical resection , radiotherapy or a combination may be the treatment plan .
complete or partial resection may result in mandible discontinuity , muscular disbalance , and dissymmetry in mandibular movements .
prospect to achieve proper stability and retention for conventional mandibular prosthesis are critically hampered due to the change in intra - oral conditions .
recently , endosseous implants are often used for prosthetic support in patients , treated for oral cancers . in non - irradiated mandibles .
the implant survival rate is at least 90% ( mean 96.1% , range 74.8 - 100% ) .
the aim of this case report is to describe the oral rehabilitation of non - irradiated oral cancer patient with implants , who underwent segmental mandibulectomy .
a 68-year - old male patient diagnosed with squamous cell carcinoma of verrucous variety of buccal mucosa ( t3n0m0 ) involving labial sulcus , angle of mouth and patches in retromolar space was referred to the department of prosthodontics , banaras hindu university .
the patient underwent surgery in 2001 , and after that due to recurrence of disease , in 2009 a segmental mandibulectomy with modified radical neck dissection was undertaken , which resected right side of the mandibular structure ; only a portion of ascending ramus and condyle remained . according to jewer classification it was type l 
surgical reconstruction was done only with a metal plate without bone graft reconstruction [ figure 1 ] .
his chief complaints were impaired mastication , speech , and swallowing after extensive resection of mandible in 2009 [ figure 2a ] .
clinical and radiographic examination showed roots stump and only one molar tooth was present on the left side of remaining half mandible .
the patient was willing and keen at having fixed prosthetic treatment on nonresected mandibular segment only .
pre - surgical radiographic evaluation was carried out with panoramic radiograph and ct dentascan [ figure 2b ] for appropriate treatment planning .
segmental mandibulectomy and reconstruction with a metal plate pre - operative intraoral view pre - operative dentascan showing available bone width and height treatment plan of placing four endoosseous implant ( hi - tec tapered self - threaded , life care devices private limited , israel ) was selected .
the diameter of implants used was 3.75 , 4.2 , and 5 mm with variety of lengths ( 8 - 13 mm ) , depending on the bone morphology .
surgical stent was placed , and after sequential drilling implant was placed in bone with the insertion torque of 35 - 45 n cm [ figure 3a ] .
appropriate antibiotic ( amoxicillin 500 mg , 3 times daily for 7 days ) and analgesic ( ibuprofen 800 mg , every 4 - 6 h as needed ) were prescribed and postoperative instructions were given .
a 2 - 3 month of the healing period was allowed to ensure osseointegration prior to exposure of the submerged implants .
after healing impression was made by open window tray technique using vinyl polysiloxane impression material ( aquasil , milford , de ) .
four tapered self - threaded implant ( hi - tec tapered self - threaded , life care devices private limited , israel ) of varying diameter 3.75 , 4.2 and 5 mm and lengths ( 8 - 13 mm ) was inserted to desired depth after sequential osteotomy the master cast obtained was mounted on a semi adjustable articulator .
the working cast was then sent to laboratory for fabrication of cement retained fixed prosthesis .
the trial of metal ceramic bridge was made ; occlusion was corrected and cemented onto the implant [ figure 3b ] .
follow up was carried out at 6 , 12 and 18 months interval and it was observed that implants were adequate in function and esthetics .
metal ceramic bridge is trial and cemented on implant abutment after 36 months , patient reported with slight mobility with respect to prosthesis . on clinical examination a screw fracture in one of the implant was detected [ figure 4a ] .
the implant retained prosthesis was removed , and implant with screw fracture was made a sleeper implant , and the case was restored with remaining three implants supporting cement - retained fixed prosthesis [ figure 4b ] .
follow up was done at 3 , 6 , and 12 months [ figure 4c ] .
intra - oral view of fracture abutment screw the implant - retained prosthesis is removed , make implant with screw fracture as sleeper implant , and restored the remains three implant with cement - retained fixed prosthesis orthopantomogram 1 year after rehabilitation
verrucous carcinoma is a variant of scc but shows different clinicopathological behavior of local invasiness , low - grade malignancy and rarely shows distant metastasis .
the most common site is the buccal mucosa ( 57.9% ) , followed by the tongue ( 13.2% ) , and t3 lesions are the most common type ( 34.2% ) .
surgical treatment of oral - cancer often results in an unfavorable anatomic and biomechanical situation , like limitation of mouth opening from scarring , impaired function of the tongue , loss of labio - lingual sulcus , deviation of mandible , lack of underlying bony support for the facial features , and adequate soft - tissue for restoration of speech and swallowing .
lateral defects , in which posterior component of dentition remains only on one side of the arch , are particularly difficult partial dentures to design . the extremely long lever arms and compromised edentulous bearing surface contribute to excessive movement of the prosthesis during function . in this patient ,
only second molar was present on remaining segment of the mandible , thereby a cast - partial denture with a good prognosis was ruled out .
mcgill consensus in 2002 suggests that the restoration of the edentulous mandible with a conventional denture is no longer the most appropriate first choice prosthodontic treatment .
there is now overwhelming evidence that a 2-implant overdenture should become the first choice of treatment for the edentulous mandible .
mandibular 2-implant overdentures have been shown to be superior to conventional dentures in randomized and nonrandomized clinical trials that ranged in duration from 6 months to 9 years .
studies of several populations have shown that ratings of quality of life are significantly higher for patients who receive 2-implant overdentures ( opposing complete maxillary conventional dentures ) than for those with new conventional dentures .
the patient refused bone graft reconstruction , and was unenthusiastic because of cited reasons of missing teeth on opposing maxillary arch , additional economic burden , time requirement and further surgical intervention and accompanying discomfort .
the patient was opted for fixed treatment option and rejected the implant supported overdenture option .
fixed implant supported prosthesis , however is limited to patients who have an adequate amount of remaining mandible .
a fixed restoration provides the psychological advantage of acting and feeling similar to natural teeth , whereas an overdenture , even if fully implant supported , remains a removable prosthesis .
the length of the cantilever in the final prosthesis is also a point of discussion .
the choice of distally implant supported fixed partial denture was made keeping in mind the altered muscular force vector and change in chewing cycle envelope .
a cantilever anterior implant supported fixed partial denture design may not be advisable due to altered force dynamic .
dental implants have a significant role in the treatment of oral cancer patients in terms of an oral prosthesis .
various factors can influence the healing and survival rates of implants , but it positively improves happiness , physical and mental health , and enhances quality of life of oral cancer patients .
surgical management of oral cancer lesions results in explicit aesthetic and functional disfigurement , including facial deformity , loss of hard and soft tissue , impaired speech , swallowing and mastication , which modify the patient 's self - image and quality - of - life . 
 recent advances in head and neck reconstruction techniques and dental implant based prosthetic rehabilitation may significantly improve the quality - of - life and self - esteem for such post - surgery patients . 
 this clinical report describes rehabilitation of oral cancer patient having segmental mandibulectomy with implant - supported fixed partial denture .