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Experience in the use of a heterologous collagen, extracted from bovine Achilles' tendon by a non-denaturing procedure, is reported. Normal tooth extraction procedures, periodontal surgery, treatment of alveolitis, oroparanasal communications and maxillary cysts, and oral surgery in patients affected by a defective haemostatic mechanism, benefit from its use.
With the recent development of copy-milling systems for porcelain, it has now become possible to construct fitting restorations from natural human tooth substance. This preliminary study aimed to find out whether it is possible to produce a well fitting Class II inlay from an extracted tooth using a copy-milling machine, so that the inlay produced will have enamel over its whole outer surface and dentine on its inner surface. Two pairs of matching sound extracted permanent molars were used. The molars were matched for mesio-distal size of the tooth crown and the convexity of the approximal surfaces. One tooth of each pair was assigned to be the 'donor' tooth, the other tooth being the 'host'. MO inlay preparations were made in the 'host' teeth. These were restored with the milled 'natural inlays' produced from the 'donor' teeth using the CELAY system. The restored 'host' teeth were sliced and examined using light-microscopy. All specimens showed a good fit and the desired location of enamel and dentine. The milling accuracy was assessed in a second experiment. This experiment showed similar marginal gaps for 'natural inlays' as for ceramic inlays. This study has shown that by using the CELAY milling machine it is possible to 'recycle' extracted teeth for the production of accurate restorations.
OBJECTIVE: The purpose of this study was to investigate the capability of polypeptide tooth paste for remineralization of human enamel. METHODS: 8 enamel slabs,which were taken from extracted tooth for orthodontics reason, were immersed in artificial cariogenic solution for 0.5h. Then,the slabs were treated by tooth paste with polypeptide and tooth paste without polypeptide for 5 min. After tooth paste were washed away by warm water, the slabs were immersed in artificial saliva. The experiment were carried out twice per day for 15 days. Two slabs were taken from test group(treated by tooth paste with polypeptide) and control group (treated by tooth paste without polypeptide) on the twelfth day and fifteenth day, respectively. The Ca(2+) content in enamel slabs were determined by electroprobe and analyzed by image process. RESULTS: The content of Ca(2+) in test group was higher than that in control group significantly. CONCLUSION: The polypeptide tooth paste has certain capability of inhibiting demineralization for human enamel.
BACKGROUND: Porous bovine bone mineral (PBBM) has been used in ridge preservation procedures following tooth extractions. The aim of this study was to investigate histochemically tissue sockets grafted with PBBM at 9 months post-extraction. By using different histochemical stainings, characteristics of the newly formed bone; i.e., lamellar/woven ratio at different socket depths, were investigated and the arrangement of bone around the grafted material, as well as the nature of the amorphous organic material found in all specimens, were examined. METHODS: After extraction of 15 single-rooted maxillary teeth from 15 patients, socket sites were grafted with PBBM particles (250 to 1,000 mu). Primary soft tissue closure of the grafted site was established using the rotated split palatal pedicle flap technique. At 9 months, a cylindrical tissue specimen, 2.5 mm in diameter, was trephined from each previously grafted site followed by placement of a screw-shaped implant. Horizontal tissue section cuts, 5 mu wide, were prepared for histological examination. Histochemical staining included alcian blue, periodic-acid Schiff, Mallory trichrome, reticulin, Van Gieson, and picrosirius red (PSR). PSR stained slides were further evaluated morphometrically, using polarized microscopy to determine the amount of lamellar versus woven bone in superficial, mid and deep specimen section cut areas. RESULTS: All staining methods revealed that newly formed bone encircled and adhered to the grafted material in most specimens. Mallory trichrome staining showed osteoblasts present within an osteoid layer, lining the interface zone of PBBM particles and the new osseous tissue. Morphometric evaluation of the PSR stained slides disclosed a constant pattern of increased osseous tissue in a coronal-apical direction. An average of 17.1% osseous tissue with 1:12.9 lamellar/woven bone ratio was calculated in the superficial area. The average bone tissue fraction was 48.3% with a lamellar/woven ratio of 1:3.8 in the mid section area and in the deep area, it increased to 63.9%, with a lamellar/woven ratio average of 1:1.7. Differences between ratios at these sites were statistically significant (P<0.001). An amorphous organic substance was noted in most grafted particles. This material usually attached cell striae and harbored glycoproteins as revealed by periodic-acid Schiff and alcian blue stainings. Mallory trichrome staining showed denatured protein within the decalcified mineral particles; reticulin, Van Gieson stainings, and polarization of PSR stained sections refuted the existence of collagen in the grafted particles. CONCLUSIONS: Cancellous PBBM is a biocompatible filler agent in extraction socket sites and an acceptable graft for edentulous ridge preservation at sites prepared to receive endosseous implants. The osteoconductivity of PBBM was determined based on promoting osseous ingrowth and close integration with the newly generated bone. Grafted particles were not significantly resorbed at 9 months. Further studies are needed to determine the resorbable capability, as well as the nature and significance of the amorphous organic substance of PBBM observed in the grafted particles.
The purpose of this study was to test the hypothesis that retraction of maxillary front teeth may lock the mandible in a posterior position, and to evaluate any relationship between condylar position and signs and symptoms of internal derangements in the temporomandibular joint. A total of 29 female patients treated for Angle Class II, Division 1 malocclusion with extraction of maxillary first premolars and 34 female patients treated for Angle Class I malocclusion without tooth extraction consented to participate in a radiographic and clinical follow-up examination. The mean ages of the patients were 16.9 (SD 3.0) and 16.6 (SD 2.6) years, and the mean times after treatment were 1.6 (SD 1.0) and 1.5 (SD 0.9) years, respectively. Condylar position was measured in percent anterior and posterior displacement from absolute concentricity on lateral, central, and medial tomographic sections of each joint. Mean condylar position was more posterior at right central (P less than 0.05) and medial (P less than 0.01) tomographic sections in patients treated with extraction. The difference was due to a higher frequency of anteriorly positioned condyles in the nonextraction cases. No intergroup differences in the sagittal occlusal slide from CR to CO and the number of patients with clicking were found. However, the condyles were located more posteriorly in all tomographic sections (P less than 0.05 for lateral, P less than 0.001 for central and medial) in patients with clicking than in those without.
The aim of this paper is to show the causes of the dental extractions in the Navarra Health Service-Osasunbidea. For 6 months all the dental extractions carried out in the clinics of the Navarra Health Service in Pamplona were registered. Data was registered for each extraction carried out. A note was made of the age and sex of the patient, the tooth extracted and the cause of the exodontia. The causes considered were: periodontia, caries, mixed causes, orthodontia, fracture and others. 4,259 extractions were carried out; 62.1% were on men and 37.9% on women (significatively different from the general population, p < 0.0001). The average age was 53.14 years (SD = 16.77 years, 95% CI: 52.62 to 53.66 years). 49.9% of extractions were due to caries, 33.7% for periodontal reasons, 3.6% for mixed causes, 1.6% for orthodontia, 0.7% because of fracture, and 10.4% for other causes. There were statistically significant differences in the distribution by sexes of the exodontias due to periodontia (p = 0.0001), orthodontia (p < 0.0001) and other causes ((p = 0.0009). The average age of the exodontias due to periodontia, accumulated in the front teeth, was greater than that for caries (p < 0.0001), accumulated in the back teeth. The average age of the exodontias due to orthodontia was 20.16 years (p < 0.0001 with all of the other causes).
This case report presents an alternative treatment option for the premature loss of a maxillary anterior tooth due to severe periodontitis. A natural tooth pontic acid-etch prosthesis was fabricated using the patient's clinical crown from the extracted tooth. This measure proved to be a very adequate, esthetic treatment solution before a permanent restorative plan could be developed for the patient's long term dental needs.
A geographical sample in a rural area of eastern Guatemala revealed widespread, premature and heavy losses of permanent teeth. Social and environmental influences that affect tooth loss include inadequate diet, refined sugar, poor oral hygiene, absence of fluoride, lack of preventive education and insufficiency of dental care services. Land hunger and family poverty are of paramount importance. Gender-based cultural differences are apparent in tooth extraction rates, and use of dentures. No one escapes visitations of severe orofacial pain that cast a blight upon the quality of rural life. Periodontal disease drives the poorest of the poor to spend disproportionately large sums on pharmaceutical pain-killers and destructive traditional medicines. Lay 'tooth-pullers' visit remote rural homes to extract teeth. Only full edentulism can bring patients permanent somatic and financial relief. Community dental health is conspicuously neglected in official policies and plans for rural development.
The present study was so designed to evaluate the change of topesthesia based on the degree of resorption of deciduous teeth and the grade of root formation of permanent teeth. A total 12315 teeth (6140 deciduous teeth and 6175 permanent teeth) from 311 boys and 364 girls, whose ages ranged from 3.9 to 17.2 years (average 8.3 years) were examined. After taking dental X-rays, 20 g of pressure was applied on the axially direction on each tooth, and then the child was requested with his index finger to identify which tooth was perceived to be pressed. A specially designed tooth pressing device was used. For reference, the measurement of the root surface was made on an extracted tooth using a digital image analyzer (MAGISCAN-IIA). The followings were the results obtained in the present study. 1) The topesthesia of the teeth was found to be more accurate in mesially located teeth than in distally located teeth. Some children falsely indicated the mesially located teeth. 2) The topesthesia of deciduous teeth was increased more as the resorption of the teeth was progressed. 3) The topesthesia of the permanent teeth decreased as the root formation developed. 4) Negative correlation was noticed between the topesthesia and amounts of the root surface remaining. (Correlation coefficient of upper jaw -0.94, lower jaw -0.89).
The aim of the present study was to evaluate, histologically, the influence of nicotine on the socket healing after tooth extraction in rats. Eighty animals were divided into 4 groups of 20 rats each (2 control and 2 test groups). In the first and second test groups, the animals received one dose of nicotine hemisulfate solution once or twice daily, respectively. In the control groups, the animals received sterile saline once or twice daily. All solutions were injected subcutaneously on the dorsum of the animals for 4 weeks. The results showed that nicotine delayed alveolar healing, especially in terms of organization of connective tissue and osteoneogenesis. Angiogenesis was considerably impaired in the ossification area and in the gingival tissues as well. We concluded that the impairment of the healing of extraction sockets was found to be directly related to the drug dosage.
With the recent influx of osseointegrated endosseous implants in dentistry, attention has been drawn away from using endodontic stabilizers as a means of stabilizing and retaining teeth. It is our opinion that endodontic stabilizers should be considered in the treatment planning of seemingly nonretainable teeth. They are biocompatible and have the additional advantage of maintaining the periodontal membrane attachment of the remaining tooth. Extraction and subsequent replacement with osseointegrated implants should only be considered after all other means of retaining the natural tooth have been fully explored. Selective case studies from various areas of the dentition demonstrate the broad applicability of stabilizers. A technique is presented for the use of endodontic stabilizers.
Guided bone regeneration using an absorbable membrane combined with one-stage implants was used to treat a 45-year-old woman. Two months following tooth extraction, two implants were placed--one in the extraction site and one in a healed site. An absorbable membrane was applied to cover the bony defect in this recent extraction site. After a 24-month follow-up, probing depths were normal, increased radiopacity was seen in the extraction site, and the implant was still clinically stable.
A method is presented which for the first time demonstrates the possibility of storing a human tooth over a period of 18 months in a frozen state with the periodontal membrane preserved viable, enabling the thawed tooth to heal with a normal periodontal ligament evaluated 2 years after autotransplantation. The cryopreservation technique included equilibration of the extracted tooth into 10% DMSO (dimethylsulphoxide) at room temperature in tissue culture medium including 10% human serum, freezing with a controlled rate of 1.2 degrees C/min to -40 degrees C and 6 degrees C/min to -100 degrees C, followed by transfer to and storage in liquid nitrogen at -196 degrees C. The tooth was thawed at a fast rate of approximately 100 degrees C/min, and DMSO was removed by slow equilibration at room temperature. A mature human bicuspid was autotransplanted after cryopreservation. Endodontic treatment was initiated 4 weeks after transplantation. 2 years after transplantation, the grafted tooth showed clinically and radiographically normal periodontal healing without signs of root resorption or marginal bone loss.
The purpose of this study was to evaluate the association between loss of ovarian function and bone mineral density changes in the mandibles of ovariectomized rabbits using peripheral quantitative computed tomography. Twenty-four adult female Japanese white rabbits were used in this experiment. The mandibular incisors were initially extracted to create implant bone. Twelve animals were bilaterally ovariectomized and the other twelve sham-ovariectomized 12 weeks after tooth extraction. All rabbits were sacrificed at 4 and 12 weeks after ovariectomy and sham-ovariectomy, with 6 rabbits in each of the four resultant groups. The edentulous parts of distal mandibular bodies were measured by peripheral quantitative computed tomography. There were significant decreases in total bone mineral density and trabecular bone mineral density in the mandibles of rabbits at 12 weeks post-ovariectomy. The results demonstrate the mineralized bone loss in the mandibles of ovariectomized rabbits.
The ART technique consists of hand excavating carious tissue and placing a highly viscous glass ionomer cement as a restoration material and as a sealant. Although the results of several studies are promising, the retention rates of these restorations for primary teeth are not impressive. Materials and methods that yield greater success rates are needed to improve long-term caries management outcomes. In principle, ART should yield outcomes similar to those associated with preservative dentistry, including the potential for minimal surgical intervention, conservation of sound tooth structure, avoidance of pain and need for local anesthetic injections, reduced risk for subsequent endodontics and tooth extraction, and increased survival time of the affected teeth. The ideal direct-filling ART material would be biocompatible and tooth colored; "forgiving" in its handling properties; insensitive to moisture or desiccation; hardenable without special equipment; able to form stable bonds to enamel and dentin; able to seal marginal gaps against bacteria; capable of releasing fluoride or remineralization and antibacterial agents when demineralization is most likely; and resistant to chemical attack. The highly viscous glass ionomer materials currently used for ART meet several of this criteria, though they may be deficient in their ability to seal marginal gaps against bacteria and in their sensitivity to desiccation. Furthermore, although they release fluoride over the lifetime of the restoration, this fluoride release alone may not prevent caries progression in all cases. It is necessary for cases of high caries risk to use chlorhexidine in conjunction with fluoride to achieve caries arrest and remineralization of adjacent areas of the affected teeth. Thus, while the ART technique offers some benefits in restoring function and reducing the rate of caries progression, it is unlikely that current materials will be able to arrest caries progression completely in high-risk persons.
This paper's objective is to describe a simple, economical and fast method to replace a single tooth. Utilizing an indirectly fabricated composite resin framework reinforced with polyethylene fiber and the existing tooth as pontic. This tooth can be the natural tooth or the restorative crown. In addition, this particular design allows for exact repositioning of the coronal part of the extracted tooth in its original intra-oral 3-dimensional position. This chairside technique does not require laboratory involvement.
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.
The most effective prosthetic prophlaxis could be the prevention of causes leading to tooth extractions. As now the caries and periodontal preventions are not efficient enough we are obligated to deal with the consequences of tooth loss. Even the loss of a single tooth might cause disfunctions in the masticatory system. Besides the well known consequences, like diminished masticatory, phonetic functions and esthetical problems we have to face to the consequences related to morphological changes in the dentition leading to difficulties in prosthodontic treatment planning and tooth preparation. So, the most important step in prosthodontic prophylaxis is the early replacement of the lost tooth. The early prosthetic reconstruction can only be prophylactic if it does not interfere with the normal hygienic procedures in the oral cavity. Consequently it is very important to consider all the possible factors affecting the oral hygiene during our prosthetic treatment planning. We should also consider the basic gnatological principles in designing the occlusal surface of crowns and pontics to avoid any traumatic occlusal forces related to our would be reconstructions.