Root coverage with enamel matrix derivatives

Different root coverage procedures have been used to treat cases of gingival recession defects involving single or multiple exposed root surfaces. A therapeutic advantage may be gained if periodontal regeneration is obtained in addition to coverage of the root with gingiva. This article describes the treatment of gingival recession by combining a surgical technique with an enamel matrix derivative.     

Crestal bone changes around titanium implants: a methodologic study comparing linear radiographic with histometric measurements

Generally, endosseous implants can be placed according to a nonsubmerged or a submerged technique and in 1-piece or 2-piece configurations. Recently, it has been shown that peri-implant crestal bone reactions differ significantly radiographically as well as histometrically under such conditions and are dependent on a rough/smooth implant border in 1-piece implants and on the location of a microgap (interface) between the implant and the abutment/restoration in 2-piece configurations. The purpose of this study was to evaluate whether standardized radiography as a noninvasive clinical diagnostic method correlates with peri-implant crestal bone levels as determined by histometric analysis. Fifty-nine implants were placed in edentulous mandibular areas of 5 foxhounds in a side-by-side comparison in both submerged and nonsubmerged techniques. Three months after implant placement, abutment connection was performed in the submerged implant sites. At 6 months, all animals were sacrificed, and evaluations of the first bone-to-implant contact (fBIC), determined on standardized periapical radiographs, were compared to similar analyses made from nondecalcified histology. It was shown that both techniques provide the same information (Pearson correlation coefficient = 0.993; P < .001). The precision of the radiographs was within 0.1 mm of the histometry in 73.4% of the evaluations, while the level of agreement fell to between 0.1 and 0.2 mm in 15.9% of the cases. These data demonstrate in an experimental study that standardized periapical radiography can evaluate crestal bone levels around implants clinically accurately (within 0.2 mm) in a high percentage (89%) of cases. These findings are significant because crestal bone levels can be determined using a noninvasive technique, and block sectioning or sacrifice of the animal subject is not required. In addition, longitudinal evaluations can be made accurately such that bone changes over various time periods can be assessed. Such analyses may prove beneficial when trying to distinguish physiologic changes from pathologic changes or when trying to determine causes and effects of bone changes around dental implants.     

Analysis of the endogrammes developed during obturations on extracted teeth using system B.

The ability of an obturation technique to fill the root canal system tridimensionally depends partially on the timing and intensity of force applications. The aim of this study was to use the Endographe to analyze the forces and wedging effects developed in the root canal using a new obturation technique: System B. This system uses a heat plugger that simultaneously heats and pushes gutta-percha. The plugger was used to soften and move the gutta-percha apically during the down-pack stage. Two different methods, however, were used to withdraw the plugger from the compacted gutta-percha. One used the burst heat method, and the other was cold withdrawal. Five endodontists performed 50 obturations of prepared extracted teeth and 50 obturations of the "wedging effect" holder of the Endographe. The practitioner-obturation assignment was randomized. For each obturation the biggest plugger possible in relationship to the shape of the canal was chosen. For the obturation of the special holder the same tip was chosen. Endogrammes showed the force application and wedging effect sequences. The mean values for the vertical and horizontal forces and the wedging effect were, respectively, 16 +/- 2 N, 5 +/- 1 N, and 9 +/- 1 N. These results suggest that System B is one of the best techniques in terms of the developed vertical forces (low values) and the resulting wedging effect (high values) in relationship to the plasticity of the gutta-percha. The Endogrammes provide a new approach to the analysis of obturation techniques and a means to demonstrate correct and optimal manipulation of the new System B plugger.     

Clinical evaluation of amalgam bonding in Class I and II restorations

BACKGROUND: Many dental practitioners are bonding amalgam to tooth structure. Although in vitro studies support this procedure, its efficacy has not been adequately confirmed in the clinical environment. METHODS: The authors placed traditional Class I and Class II bonded and unbonded amalgam restorations in 76 patients. Panavia 21 (J. Morita USA Inc.) was the bonding agent selected, and Aristaloy CR (Englehard Dental) and Tytin (Kerr Corp.) were the amalgam alloys used. Postoperative sensitivity and marginal fracture were evaluated at yearly intervals, for up to three years of clinical service. RESULTS: At the patients' appointment for polishing one to two weeks after restoration placement, and at each yearly recall appointment, the authors found no significant difference in postoperative sensitivity between bonded and unbonded restorations for either amalgam alloy (chi 2 analysis, alpha = .05). In addition, there was no significant difference between bonded and unbonded restorations for either amalgam alloy with respect to marginal fracture (analysis of variance and Tukey's contrasts at alpha = .05). Moreover, no cusp fractures were observed for either bonded or unbonded restorations. CONCLUSIONS: After three years of clinical service, amalgam bonding for traditional Class I and Class II restorations had no effect on postoperative sensitivity or marginal integrity. CLINICAL IMPLICATIONS: The merit of using adhesive bonding agents for traditional Class I and Class II amalgam restorations was not demonstrated in this three-year clinical study.     

Human odontoblast cell numbers after dental injury

OBJECTIVES: The purpose of this study was to measure the changes in odontoblast cell numbers in response to cavity restoration variables and patient factors, and the effect these factors have on dental repair by tertiary dentinogenesis. The number of vital odontoblasts is a critical factor for pulpal repair following restorative surgery, and yet little information is available on these cell numbers. METHODS: Class V non-exposed cavities were prepared in the buccal surface of intact first or second premolar teeth of 27 patients, between 9 and 17 years of age. Following tooth extraction (28-163 days) the area of reactionary dentine and the area of the odontoblasts were measured histomorphometrically. RESULTS: Patient factors, as well as cavity preparation and restoration variables, had little effect on the numbers of odontoblasts per pulpal unit area. However, the age of the patient did appear to have an effect on the reactionary dentine secretory capacity of odontoblasts per unit area, and on the relative number of odontoblasts beneath cut dentinal tubules. CONCLUSIONS: Odontoblast cell numbers were maintained following the preparation of cavities cut into dentine with a 0.5mm residual dentine thickness. The repair capacity of the pulp-dentine complex would appear to be age dependent, this may explain differences in the success of various restorative treatments between patients.     

Continuing dental education in osseointegrated implants. A survey

A survey of participants in a continuing education course in osseointegrated implants was carried out to determine dentists' attitudes toward such courses and how they were integrating implants into their everyday practice. The results indicated, despite the intense program, very few general dentists who attended such a course chose to actively participate in implant placement and a moderate number chose to carry out prosthetic restoration. Those who attended such courses appeared satisfied with the course content, appreciated the difficulties involved with implant placement and restoration and generally chose to refer such cases to appropriate specialists for management. This pilot study confirms dental implants are a popular and accepted mode of therapy. However, general dental practitioners who take the time to undergo specific training in osseointegrated implants appear to be less inclined to actively participate in the placement (surgery) of implants. Following appropriate training, many general practitioners felt comfortable in performing the restorative/prosthetic aspect of implant treatment for single tooth rather than partial or full denture cases. In conclusion, while continuing education courses in osseointegrated implants are becoming increasingly popular, this survey indicates participants become aware of the complexity of the procedures involved and tend to actively participate mainly in the prosthetic reconstruction of simple cases.     

Treatment of middle-apical level root fracture in necrotic teeth

The purpose of this paper is to present two case reports of dental trauma with middle-apical level root fractures and pulp necrosis. The treatment consisted of programmed applications of calcium hydroxide until a calcified barrier was formed at the fracture level. The technique presented here proved efficient in treating horizontal fractures at the middle and apical thirds of the root.     

Hepatitis C infection and associated oral health problems

Hepatitis C infection is widespread throughout the community. This study aimed to assess the status of oral health of persons infected with hepatitis C. DMFT and CPITN indices were recorded at a clinic providing priority dental care for people with hepatitis C infection. The data were compared with information from an existing survey of general dental patients. Social impact was assessed using a modified Oral Health Impact Profile questionnaire. The DMFT index differed significantly between hepatitis C and general patients. The number of decayed and missing teeth was greater in those infected with hepatitis C for all patients aged between 25 and 50 years. Although there was no significant difference in CPITN categories for subjects evaluated, a marked trend for poor periodontal health was noted for those individuals with hepatitis C. Salivary flow was reduced in 50 per cent of hepatitis C infected subjects. Social impact was significantly affected with 71 per cent of hepatitis C subjects reporting painful aching in the mouth and 56 per cent having difficulty in relaxing. In conclusion, the results from the project strongly indicate an urgent need for priority delivery of dental care for people with hepatitis C infection.     

Human histologic evaluation of a bone graft combined with GTR in the treatment of osseous dehiscence defects: a case report

There are many possible goals and outcomes of periodontal surgical therapy, but the ultimate goal is regeneration. Since the definition of periodontal regeneration is histologic, it is difficult to document. The purpose of this study was to evaluate a technique that combined a bone graft and guided tissue regeneration (GTR) to see if regeneration occurred. Four teeth with dehiscence-type osseous defects that were scheduled for extraction were treated with bone grafts and GTR. During the surgical procedure, a notch was placed into the root at the apical extent of the calculus. The teeth were extracted with conservative block sections 7 months after the treatment. They were processed, sectioned, stained, and evaluated histologically. The results revealed that regeneration did not occur in any of the teeth treated. In 2 of the teeth new connective tissue attachment was formed. In these 2 teeth cementum could be seen in the notch with connective tissue fibers inserting into the cementum. In one of the teeth the junctional epithelium extended apical to the notch, while in 3 cases the epithelium stopped at or coronal to the notch. In this case report, no regeneration could be documented, but new attachment could be seen in 2 of the 4 teeth treated.     

Analysis of radiologic factors in determining premolar root canal systems

OBJECTIVES: Certain tooth groups pose problems as to radiologic determination of root canal morphology. For example, the premolars may have superimposed roots that give the appearance of a single canal when 2 are actually present. This study examined the effect of X-ray tube inclination so as to visualize the complete root canal system in premolars. STUDY DESIGN: One hundred extracted premolars were divided into 4 groups of 25 teeth each: 1MxP (first maxillary premolar), 2MxP (second maxillary premolar), 1MdP (first mandibular premolar), and 2MdP (second mandibular premolar). A total of 10 radiographs were made of each tooth in the horizontal and vertical planes (horizontal angles of 0, 20, and 40 degrees, then vertical angles of 0, 15, and 30 degrees). Logistic regression analysis was used for the statistical analysis of the results--the dependent variable being the number of canals visualized. RESULTS: On varying the horizontal angle (20 and 40 degrees), the number of root canals observed in the case of 1MxP, 2MxP, and 1MdP coincided with the actual number of canals present. In the case of 2MdP, only the 40 degree horizontal angle correctly identified the number of canals regardless of the vertical angle (although only 4% had more than 1 canal). CONCLUSIONS: Varying the horizontal angle improved the visualization of additional (superimposed) canals in premolars. Changing of the vertical angle had no statistically significant influence except for the first mandibular premolars.