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Endodontically treated teeth are susceptible to bacterial contamination through exposure to oral fluids. It is crucial, therefore, that restorations placed during and after root canal therapy protect the root canal from oral contamination. This paper highlights the clinical steps necessary to reduce the risk of contamination in root-filled teeth.
The restorative management of patients with localised tooth wear is a major challenge to the dental profession. There is rarely adequate interocclusal space available to place restorations without the need for extensive tooth preparation or the involvement of many unaffected teeth. In 1975, a method was described which created interocclusal space by the use of a partial coverage appliance made of cobalt chromium alloy. The technique reduced the need for more invasive palatal reduction. This paper, with the aid of clinical case examples, highlights the development and evolution of the original removable appliance. However, there remains a need for further clinical studies to evaluate fully these techniques.
Research into root canal preparation has led to significant changes in instrumentation techniques. Hand files should be manipulated by the balanced-force technique. Recent designs of endodontic instruments have variable tapers giving improved shaping ability. Nickel-titanium rotary instruments will rapidly and safely open the main root canals creating deep space to permit full permeation of irrigant solutions. Practitioners considering changing their endodontic technique are advised to attend hands-on practical courses to gain competence before using these in clinical practice.
A retrospective clinical audit of the role and survival of 69 Rochette bridges used as immediate provisional restorations for single tooth, implant-retained crowns was carried out over the period between February 1991 and May 2001. In each case the extracted tooth was immediately temporised using a Rochette bridge with a single wing and pontic and cemented to the abutment tooth without any tooth preparation (Phase I). This bridge was removed at the time of implant placement and recemented (Phase II). At the implant exposure stage the bridge was removed and discarded. In Phase I, 15.9% of the bridges required recementation and 27.5% of the bridges required recementations in phase 2; 7.2% of the bridges required recementations in both phases. An 80% probability of survival was noted after an interval of 200 days for phase I and a 78% probability of survival over the same time interval was observed for Phase II. A significant debond rate was observed when the retainer was a canine in comparison to the other bridges in Phase I. In Phase I the spring cantilever debond rate was significantly higher than that observed on the other bridges. More debondings were observed in males (25.8%) compared with females (7.9%) in Phase I. More debondings were noted in the maxilla than in the mandible in Phase II. The performance characteristics of the metal acrylic Rochette bridge observed in this report supports the conclusion that this type of restoration is an effective means of immediate temporisation for patients undergoing single tooth implant retained restorations.
One major obstacle to treatment with implants is the transitional phase between a tooth supported occlusion and an implant supported occlusion. This is of particular concern when a patient with a failing dentition has not worn a removable prosthesis before and is planning to have a reconstruction supported by implants.
Orthodontic treatment of partially edentulous patients is difficult, especially if a significant number of teeth are missing. With loss of teeth, adjacent or opposing teeth usually tip, drift or over-erupt leaving spaces that are not optimal for replacement of missing teeth. Orthodontic correction of these spatial relationships will aid prosthetic replacement of the missing teeth, function, hygiene and aesthetics. Orthodontists rely on teeth to provide the anchorage to correct malocclusions. With patients with an intact dentition dental anchorage is usually adequate to facilitate tooth movement. In some partially edentulous patients however, insufficient anchorage may present to correct the malocclusion. In these patients implants can provide additional anchorage. At times, osseointegrated implants can also be used to support restorations after completion of orthodontic therapy if treatment planning is precise. The use of implants for orthodontic anchorage requires an interdisciplinary approach and precise planning to achieve optimal results.
AIM: The purpose of this case report is to stress the importance of taking a proper history and the appropriate evaluation of diagnostic tests in order to prevent incorrect diagnosis and treatment. Moreover, the management of postoperative problems in a healthcare system in which specialists take on specific parts of the treatment is discussed. SUMMARY: This article describes the diagnosis and treatment of an unsuspected flare-up 1 week after root canal treatment. The swelling and pain appeared to be associated with an accidentally embedded piece of impression material. General practitioners and specialists should be aware of alternate treatment plans and treatment procedures and take these into consideration whenever there is a postoperative problem to be solved. KEY LEARNING POINTS: Impression materials can cause a foreign body reaction when embedded in the soft tissues. History taking and evaluation of diagnostic tests are of paramount importance in order to prevent incorrect diagnosis and treatment. Both general practitioners and specialists have the responsibility to evaluate patients with a broad vision.
This in vitro study reports on the cleaning effect of different soaps on the shear bond strength of various dentine-bonding agents. Human teeth were coated with provisional cements for 24 h or for 14 days. After removing the provisional cements with a scaler, the dentinal surface was cleaned with a cotton pellet and non-fluoridated flour of pumice and soap for 10 sec. Different dentine-bonding agents and a luting resin were bonded to the dentinal surface according to manufacturers' instructions with the bonding agent and the composite material being light-cured at the same time. The bonding agents were tested under intrapulpal pressure and with thermal cycling to imitate physiological conditions. Compared with cleaning the dentine with water and pumice, all soaps investigated in this study decreased the shear bond strength values of the tested dentine-bonding agents considerably.
This article describes a technique for fabricating a provisional screw-retained restoration for immediate loading of single implants. Until immediate loading of single implants becomes a well-documented treatment modality, this technique should be used cautiously.
In this article, 4 techniques for fabricating provisional restorations for ITI solid abutments are described. The use of a burn-out coping, acrylic resin coping, impression cap, and protective cap are presented, and the advantages and disadvantages of each are discussed.
A review of the literature was performed to determine whether prompt placement of coronal restorations, including sealing and placement of posts and cores, can positively influence the long-term prognosis of teeth after root canal therapy. Both hand and MEDLINE searches were employed to identify peer-reviewed articles on radicular apical integrity after coronal restorations, especially where root canal space was used for post and core fabrication. A total of 41 articles published between 1969 and 1999 (the majority from the 1990s) were reviewed. The literature suggests that the prognosis of root canal-treated teeth can be improved by sealing the canal and minimizing the leakage of oral fluids and bacteria into the periradicular areas as soon as possible after the completion of root canal therapy.
STATEMENT OF PROBLEM: Residual provisional cement and debris on prepared teeth may have the potential to negatively influence the performance of the definitive luting agent. PURPOSE: This in vivo study quantified the adherence of provisional cement to abutment teeth prepared with 1 of 2 textures (coarse or fine) and cleaned with 1 of 3 common cleansing techniques. MATERIAL AND METHODS: One hundred ten provisional restorations in 22 patients were luted to maxillary anterior abutment teeth. The teeth were prepared for complete veneer restorations with either a coarse-grit diamond bur or a coarse-grit diamond bur followed by a fine-grit diamond bur. After removal of the restoration, abutment teeth were randomly cleansed with either a No. 23 dental explorer and air-water spray, a prophy cup with fine flour pumice, or a cotton pellet soaked in chlorhexidine gluconate, 0.12%. After the abutments were cleansed, they were evaluated intraorally under a light microscope (magnification, x64) by 2 blinded examiners. The teeth were given scores based on the number of specks of residual cement found on the surface after the cleansing techniques were performed. Pearson correlation coefficients (alpha=.96), 3-way analysis of variance, and post hoc Scheffé tests (P<.05) were used to analyze the data. RESULTS: As determined with Pearson correlation coefficient, the interexaminer reliability was alpha=.96. Three-way analysis of variance revealed significant effects for the cleansing techniques but not for the interaction between cleansing techniques and preparation texture. A post hoc Scheffé test showed that the pumice cleansing technique (1.8 specks/tooth) was significantly better than the explorer or the cotton pellet/chlorhexidine gluconate technique (3.6 and 3.5 specks/tooth, respectively) (P<.05). CONCLUSION: Within the limitations of this study, abutment teeth cleansed with a prophy cup and flour pumice exhibited the least amount of residual provisional cement.
The technique described in this report is an expansion of a previously reported intraoral procedure for directly developing a matrix for the fabrication of composite cores. The expanded method allows a matrix to be created indirectly after the involved teeth are trimmed or restored on a cast into slightly oversized crown preparations before the treatment visit. The cast may serve for both the matrix and the interim fixed restoration, enabling fabrication by the dental laboratory. A semirigid (occlusal registration) elastomeric material is used to form the matrix. The matrix is used to apply the composite and shape the cores after the abutment teeth have been prepared, pins or posts have been placed, and adhesive procedures have been implemented. The elastomeric matrix can be modified for use as the impression matrix. The described technique allows the simultaneous formation of multiple composite cores. An alternative method in which light-polymerized core composite is used with a vacuum-formed, dual-laminate transparent matrix is described and compared with the semirigid elastomeric matrix.
This article describes 2 patient treatments in which a simple technique was used to realign teeth before restorative procedures. Elastic separators were used to tip the desired tooth into its original position. This restored a normal crown contour and improved the tooth's long-axis alignment. The procedure is simple and inexpensive, and treatment time relatively quick compared with other orthodontic procedures.
STATEMENT OF PROBLEM: The dental literature has shown a 3% to 25% pulpal necrosis rate as a result of tooth preparation for complete coverage restorations. PURPOSE: The purpose of this retrospective study was to examine clinical and radiographic records for evidence of pulpal necrosis in teeth prepared for complete coverage restorations at ultrahigh speed when air coolant alone was used. MATERIAL AND METHODS: The 1847 teeth in this study (182 fixed partial denture abutment teeth and 1665 single teeth restored with 21 all-ceramic, 1095 metal-ceramic, and 731 all-metal restorations) were prepared with diamond instruments (burs) in a sweeping or painting motion with the use of light pressure (1-3 oz) at ultrahigh speed with air coolant alone from the handpiece. New burs were used for each patient and then discarded. Each bur was used on no more than 4 teeth. All impressions were made with reversible hydrocolloid. Provisional restorations were fabricated on a stone cast and cemented with zinc oxide and eugenol cement. Provisional restorations were removed at 3 to 4 weeks and definitive restorations placed. Between 1970 and 1989, 6 different luting agents (zinc phosphate, resin, glass ionomer, ortho-ethoxybenzoic acid, carboxylate, and polycarboxylate) were used to place definitive restorations. All patients were questioned about symptoms of tooth sensitivity, tenderness, or pain at their regular (4- to 6-month) hygiene recall appointments. Success was defined as any definitively restored teeth that remained free of radiographic evidence of periapical radiolucency and clinical signs and symptoms of pulpal sensitivity or pain recorded in the clinical record. The results were compared with rates of pulpal necrosis for teeth prepared with water coolant as reported in the dental literature published between 1970 and 1997. RESULTS: Of 638 teeth prepared between 1970 and 1979, the pulpal necrosis rate was 2.19% (14 teeth: 12 single teeth and 2 fixed partial denture abutment teeth) (97.81% success rate). Of 1209 teeth prepared between 1980 and 1989, the pulpal necrosis rate was 0.66% (8 teeth: 7 single crown teeth and 1 partial denture abutment tooth) (99.34% success rate). Of 1825 teeth prepared between 1970 and 1989, radiographic evidence of pulpal necrosis was found in 0% (100% success rate). No clinical symptoms of pain or sensitivity were recorded in the patient records for the surviving teeth during the time period of this study, which was conducted in May 2001. No crowns were repaired or removed as a result of carious lesions. No higher incidence of pulpal necrosis relative to the type of luting agent was observed. CONCLUSION: Within the limitations of this retrospective study, it is suggested that tooth reduction procedures can be completed with minimal damage to the pulp when only air coolant from the dental handpiece is used.
STATEMENT OF PROBLEM: Provisional crowns cemented with provisional luting agents are susceptible to washout, margin leakage, and secondary caries when placed for a prolonged period. PURPOSE: This study was conducted to determine the effect of combining a varnish containing 2.26% NaF with 2 provisional luting agents on the margin leakage and retention of provisional crowns. MATERIAL AND METHODS: Acrylic resin provisional crowns were fabricated for 8 shoulder-prepared molars. The eight provisional (N=24) crowns were luted individually with Temp-Bond (TB), Freegenol (FG), or Duraphat (DU). Specimens were thermocycled 500 times (5 degrees and 60 degrees C) with a 1-minute dwell time, stored in 100% relative humidity at 37 degrees C for 6 days, and then immersed in a 0.5% Gentian violet solution for 24 hours. Seven days after cementation, a removal test of the crowns (shear retention test) was conducted with a universal testing machine at a crosshead speed of 5 mm/min. Retention was determined as the maximum recorded force needed for crown dislodgment. DU varnish was applied to the inner surface of the dislodged crowns with no removal of the cement layer TB, FG (N=16). The crowns were relined with a 0.5-mm layer of acrylic resin and luted with a combination of luting agent and DU (TB, FG) N=16. No luting agent (NC) served as the control (N=8). Results were analyzed with the Wilcoxon matched-pairs signed-ranks test. Leakage at the margins was assessed with a 4-level dye penetration scale, and statistical differences were identified with a chi(2) test. All hypothesis testing was conducted at the 95% level of confidence. RESULTS: The mean 7-day retention forces were as follows: 44.5 N (Temp-Bond), 51.6 N (Freegenol), and 35.9 N (Duraphat). There were no significant differences among these values. Duraphat combined with Freegenol decreased the retention of provisional crowns, but Duraphat combined with Temp-Bond increased the retention of provisional crowns by 69-145%. Duraphat alone and in combination with both provisional luting agents significantly reduced margin leakage (P<.05). The least margin leakage was evident when the provisional crowns were luted with Duraphat alone. CONCLUSION: With regard to retention and margin leakage, the results of this study suggest that Duraphat varnish can be successfully used as provisional luting agent for single provisional crowns.
This article describes a method for fabricating multiple-unit provisional restorations by use of the indirect-direct method without the need for abutment preparation on diagnostic casts. Composite is used with fiber reinforcement to create a provisional shell in a vinyl polysiloxane matrix. This method reduces chair time, as well as laboratory time required to fabricate provisional restorations. Control of restoration contours and incisal edge position is also enhanced.
Micrognathia complicated by edentulous maxilla was treated by performing sagittal-split mandibular osteotomy and immobilizing a subperiosteal implant using transmaxillary screws. The patient was a 42-year-old man who had a birdlike facial deformity caused by significant hypoplasia of the mandible. He also demonstrated significant malocclusion attributable to micrognathia and edentulous maxilla caused by resorption of the alveolar bone. These conditions impaired his mastication and articulation, making it impossible for him to eat regular food or carry out normal conversation. A subperiosteal implant was placed on the edentulous maxilla, and was rigidly immobilized to the maxilla using five transmaxillary screws. A prosthesis was then attached to the implant, and by using the implant as the point of reference and the anchor, the mandible was moved forward by sagittal-split mandibular osteotomy. Intermaxillary fixation was subsequently performed. The postoperative course has been favorable, and his facial complexion has improved significantly. One and a half years after his surgery, there has been no sign of complications or malocclusion caused by mandibular retraction. He is now able to eat regular food and speak normally.