the dentogingival complex is composed of the gingival sulcus , the junctional epithelium and the supraalveolar connective tissue attachment . according to several authors , the integrity of this complex is important for the protection of the tooth - supporting tissues , and therefore , the maintenance of periodontal health.[13 ] caries , restorations and dental fractures often invade the dentogingival junction . such an invasion may promote soft tissue inflammation and bone resorption , especially when they infringe the junctional epithelium and supracrestal connective tissue , commonly termed as the biological width . in these cases , the surgical exposure of dental margins is often required to allow restorative procedures and to create a supraalveolar area that accommodates the newly formed biological width . supragingival margins facilitate impression making , provisional and definitive restorations and detection of secondary caries . in addition , some studies have demonstrated that subgingival restorations are associated with higher levels of gingival bleeding , attachment loss and gingival recession than supragingival restorations . the most commonly used techniques for biological width reestablishment are the clinical crown lengthening surgery ( ccls ) , orthodontic extrusion and the association of both procedures . the advantages of the aforementioned surgical technique are the decreased time for final restoration and the reduced number of clinical sessions . on the other hand , when compared to orthodontic extrusion , a greater supporting bone removal is necessary and the soft and hard tissues of the adjacent teeth are frequently involved during the surgery . although the orthodontic forced eruption preserves supporting bone and the adjacent teeth , the prolonged treatment time , the reduction of tooth insertion and the need of an orthodontic apparatus may be limitations to the clinical use of this technique . previous studies have suggested that a distance of 3 - 5 mm , from the alveolar bone crest to the crown / restoration margin , is required to accommodate the newly formed supraosseous gingival complex and to permit proper restorations . in some cases , an odontoplasty ( i.e. wearing of the dental surface creating a smooth supraalveolar area ) may be a useful maneuver during the clinical crown lengthening surgery . this approach enables the re - establishment of the dentogingival union with decreased bone removal [ figure 1a and 1b ] . caries and fractures close to furcations , the necessity for excessive supporting bone removal with conventional ccls , radicular length reduction ( observed in forced eruption ) and aesthetic damages may be indications for the performance of odontoplasty . however , to date , there is no available evidence evaluating the clinical outcome of a series of cases treated by using odontoplasty associated with ccls . thus , the aim of the present study is to retrospectively evaluate teeth submitted to odontoplasty during clinical ccls , when compared to their contralateral non - operated teeth . ( a ) schematic illustration representing the bone removal during a conventional osteotomy and the decreased bone removal when odontoplasty is associated with clinical crown lengthening ; ( b ) schematic illustration representing the reduction of dental structure after odontoplasty when compared to a tooth submitted to conventional osteotomy / clinical crown lengthening surgery after the evaluation of clinical records of patients assisted at the ufpel school of dentistry between two years , 16 subjects were selected for this study . the following inclusion criteria were used : 1-individuals submitted to ccls , performed by the same operator that carried out odontoplasty in at least one tooth ; 2-non - smokers , non - pregnant or lactant and systemically - healthy subjects ; and , 3-periodontally - healthy individuals , presenting full - mouth plaque index ( pi ) and gingival index ( gi ) lower than 20% at the moment of the surgery . patients were informed of the characteristics of the study and gave their written consent to be included in the investigation . the surgical area was free from visible plaque at the moment of the surgery [ figure 2a ] . the surgeries were indicated for the reestablishment of the biological width and dental margins exposure . in summary , the technique was performed as follows : ( a ) palatal view of the case initial condition . a subgingival loss of structure was caused by a fracture involving palatal and mesial aspects . ( e ) palatal view of the interrupted simple sutures adapting buccal and palatal flaps . after local anesthesia ( 2% lidocaine with 1:100000 epinephrine ) , an internal bevel incision was accomplished around the teeth for dental margin exposure [ figure 2b ] . an intrasulcular incision was then performed , a mucoperiosteal flap was reflected and the gingival tissues were removed to allow the visualization of the bone and the dental margins [ figure 2c ] . all the cases evaluated in the present study showed a wrinkled area with irregular outlines due to the fracture , caries or subgingival prosthetic preparation . a slight osteotomy using a mini ochsenbein chisel enabled the visualization of fracture limits that were planed by a 30-blade bur 9714ff and 9904ff ( kg sorensen , so paulo , brazil ) and periodontal curettes ( hu - friedy co , chicago , il , usa ) to create a supraosseus area of 3 mm or more [ figure 2d ] . chlorhexidine gluconate ( 0.12% ) mouthwash was prescribed twice a day for 2 weeks and analgesics were prescribed to control post - operative discomfort . figures 2f , g and h show the post - operative condition of one case at 1 week , 6 months and 16 months after surgery , respectively . periodontal probing at 6 and 16 months follow - up period revealed a clinicaly healthy gingiva . the examination was performed by a single examiner ( periodontist ) trained and calibrated for the study . the intra - examiner agreement was > 0.80 according to the kappa - light test . the following clinical parameters were measured : probing depth ( pd ) : measured from the gingival margin until the bottom of the gingival sulcus / pocket ( using intervals of 0.5 mm ) ; plaque index ( pi ) : presence ( 1 ) or absence ( 0 ) of visible plaque ; bleeding on probing ( bop ) : presence ( 1 ) or absence ( 0 ) of bleeding of up to 15 seconds after gentle probing . the parameters were recorded in six sites per tooth ( mesio , medio , disto / buccal and lingual ) in both the teeth that received the odontoplasty ( test ) , and their respective contralateral non - operated teeth ( control ) . a single manual periodontal probe ( north carolina  hu - friedy , chicago , il , usa ) the final rehabilitation outcome was also evaluated and classified as follows : 
 total success : without need for further intervention;relative success : further clinical intervention with maintenance of the tooth;failure : tooth loss 
  total success : without need for further intervention ; relative success : further clinical intervention with maintenance of the tooth ; when classified as 2 or 3 , an additional classification was used , according to the necessity of an additional dental intervention : a - periodontal : sub or supragingival calculus accumulation , and/or probing depth higher than 3 mm , associated with bop at the operated area ; b - endodontic : periapical lesion , sinus tract and/or painful symptomology ; c - restorative : marginal infiltration , secondary caries or fracture of the restoration ; d - dental fracture ; e- fracture caused by trauma ; and , f - other reasons . data was analyzed by using statistical software ( bioestat 3.0 , sociedade civil mamirau , cnpq , br ) . the mean pd of the sites involved in the odontoplasty and their respective sites on the contralateral teeth were computed for each tooth . pd of the teeth submitted to odontoplasty was compared with those of the contralateral teeth by the mann - whitney non - parametric test . mcnemar test was used to compare the frequencies of failure , their reasons , pi and bop . fourteen teeth were included in the study , being 3 lower ( all first molars ) and 11 upper teeth ( 4 central incisors , 1 lateral incisive , 1 canine , 3 premolars and 2 molars ) . table 1 shows the teeth included in the study , the reason for the surgery , the sites involved in the odontoplasty , the follow - up period and the type of restoration . the mean follow - up period was 13.57  8.00 months ( mean+standard deviation ) , and ranged from 6 months to 24 months . during this period of evaluation , no treated tooth was lost and no restorative procedure had to be repeated . with respect to final rehabilitation outcome , until the present moment , 12 patients were classified with score  1 ( total success ) and 2 with score  2  ( relative success ) . the  2  scores were due to the necessity for a new periodontal intervention ( score a ) . one patient received supragingival scaling in the operated area and another received subgingival scaling . with regard to the periodontal parameters [ table 2 ] , no statistically significant differences were observed for pi , bop and pd between the operated teeth ( test ) , and their respective non - operated contralateral teeth ( p>0.05 ) . sample description of the study periodontal clinical parameters at the sites involved in the odontoplasty ( test ) and at the respective aspect of the contralateral teeth ( control ) the great benefit of the odontoplasty technique is the reduced necessity for osteotomy [ figures 1a and b ] . the requirement for bone preservation has progressively become important with the advancements in titanium dental implants . thus , if rehabilitation failure and consequent tooth loss occur , the implant remains as a second alternative and can be placed in a region where the bone structure was preserved . although odontoplasty was initially described in 1982 as a restorative alveolar interface ( rai ) , evidence of the success of this technique on a long - term basis is very scarce . additionally , data regarding the outcome of odontoplasty in the buccal or palatal sites of the teeth are even more limited . therefore , this case series focused on the clinical outcome of teeth submitted to odontoplasty , predominantly in the buccal or palatal sites . odontoplasty is a commonly - employed clinical procedure and two relevant questions have emerged regarding this technique . the first is the resistance of the worn area and , the second relates to the periodontal health of the tissues adjacent to the worn area . the resistance of the dental remainder is even more important when the odontoplasty is carried out in teeth that have suffered extensive corono - radicular fracture with biological width invasion . the increased fragility of the dental remainder can put the long - term success of the prosthetic or restorative procedure at risk , since the tooth wear is performed at a surface that has been previously weakened by the fracture or carious process . the present cases were even retrospectively evaluated ; however , information regarding the extent to which the teeth were worn during the odontoplasty was not available . we may speculate that , despite the fineness of some areas after odontoplasty , the preservation of bone tissue in the cervical area may balance the force on the fulcrum point and , therefore , reduce the risk of fracture . the periodontal parameters revealed that the operated teeth behaved similarly when compared to their non - operated contralateral teeth ( controls ) . this finding suggests that the modification of the anatomy in the operated sites did not affect the periodontal health . in fact , according ross et al . , a normal healing occurs when odontoplasty is accomplished in proximal areas , a technique known as rai , which follows the same principles as the technique used in the present study for buccal and palatal aspects . histological studies in dogs , evaluating the rai technique , showed a similar healing pattern when odontoplasty areas were compared to areas of periodontal surgery without odontoplasty . our positive clinical findings may also be related to the hygiene instructions taught to the patients ; and , patients were motivated to modify their brushing technique and to use a tuft toothbrush when a dental unevenness among the adjacent teeth and the operated ones was observed . one of the patients presented 4 mm of probing depth , associated with gingival bleeding , in the operated site ; though initially it was suspected that odontoplasty could have influenced the periodontal condition , a complete examination of the oral cavity revealed a clinical picture of widespread gingivitis . one limitation of the present investigation is that , as a retrospective study , it was not possible to standardize the restorative materials and intra - radicular retainers . on the other hand , great care was taken with the choice of the surgical technique and restorative planning . the present clinical retrospective investigation suggests that both anatomical alteration and thickness reduction , promoted by odontoplasty , seems not to be critical for periodontal health and restorative success . however , further studies are necessary in order to evaluate the outcomes of odontoplasty in a larger sample size and during the long - term . in addition , the wear magnitude , the occlusal stability , the dental group and the type of rehabilitation also needs to be assessed in future studies . therefore , it can be concluded that odontoplasty during ccls is a feasible procedure that does not affect periodontal health and the long - term prognosis of restorative procedures .
aim : the aim of this study was to evaluate the clinical outcome of teeth submitted to odontoplasty during clinical crown lengthening surgery ( ccls ) , when compared to their contralateral non - operated teeth.materials and methods : fourteen patients submitted to odontoplasty during ccls were evaluated according to plaque index , bleeding on probing , probing depth and final restoration outcome ( total success , relative success and failure).results : the mean follow - up period was 13.57 (  8.00 ) months , and ranged from 6 to 24 months . 
 twelve cases presented total success of the final rehabilitation and 2 cases presented relative success . 
 the cases of relative success were due to the necessity for a new periodontal intervention ( scalling ) . 
 no differences were observed with respect to periodontal parameters ( p>0.05 ) and the patients that showed relative success presented generalized poor oral hygiene.conclusions:the odontoplasty during clinical crown lengthening surgery is a feasible procedure in the management of extensive crown destruction .