Quintessence International, 07/2004

My last editorial was about the changes in implant surfaces over the years, and it started me thinking. Why did the person who discovered an implant that actually worked and the company that he helped to found, not make a few changes to the design early on? I used Brånemark implants when they were first introduced to the US. The course I took was one of the two that changed my professional life (the other being Mort Amsterdam's and D. Walter Cohen's Periodontal Prosthesis course) What a revolutionary concept! One that has improved the lives of millions of people all over the world. When they first started, the company had the market virtually to itself. But now there are numerous implants and implant companies. Why? Because they were not market driven, and the market demanded stronger implants and improved prosthetic connections. The original providers found it difficult to provide these modifications. This is not meant as a criticism. Their reasons were very valid. They wanted to wait until they had long-term studies before bringing new products to the market. Good idea, but the market could not wait. The same situation has happened to other people, other institutions, and other companies. Look at Kodak. Once a worldwide leader in photographic film, it now must lay off people as a result of the rapid transition to digital. I see the same thing happening in my field. For years we periodontists have felt that we should be the leaders, the final authority, and the main provider of periodontal therapy. That all started to change in the 1960s when forward-looking men like Barkley and Arnum went around the country teaching people the joys of flossing. It took a major turn when Procter and Gamble discovered that there was money to be made from people with pyorrhea, and raised the public's awareness to degrees not possible by professionals or their associations. We began to lose the educational side when companies started giving presentations on "nonsurgical" therapy to general dentists and dental hygienists. We didn't help by refusing to officially sponsor courses like this through our official body. We lost when the "dental hygiene department" became a "profit center." And now in many schools, periodontics is taught to dental students by dental hygienists. So why did all these people, companies, and professional organizations not change? I am not sure that I know all the answers about why, but I think I know a few. They were afraid of losing their livelihoods, their companies, or control of their profession. It is comfortable to maintain the status quo. It is difficult to change. As a result, we are all afraid of change, and therefore, in spite of all the warnings, we often lose what we most want to keep. I am a firm believer in the concept that the only constant is change and that change, while painful, is necessary for growth. Get over it-change will happen. You can make it happen, or you can have it happen to you and suffer the consequences. I just opened my new computer; I am in for some pain. Thomas G. Wilson, DDS Editor-in-Chief

Periodontal surgery may be accompanied with some postoperative complications such as pain, swelling and sloughing, purulence or infection, transient bacteremia, nerve trauma, and hemorrhage. In general, a resective surgical intervention may implicate reduction in the attachment apparatus. Migration as a postoperative complication has never been addressed in the literature. This paper presents a case report detailing migration of a tooth, following a surgical preprosthetic clinical crown-lengthening procedure, which was repositioned using adjunctive orthodontics with a removable maxillary modified Hawley appliance. It is incumbent upon the dentist to examine meticulously the occlusal status of the teeth prior to a planned surgical intervention and to take measures preventing any possible tooth migration during the healing process. Failure to achieve occlusal and intra-arch stability may lead to undesired tooth movement in the arch postsurgery, affecting future prognosis and complicating any planned prosthetic work.

Objective: Methods in restorative dentistry have to meet stringent accuracy requirements. The accuracy of robotic systems used for the reproduction of condylar movements has not been determined. The purpose of this study was to assess the accuracy of the robot system, ROSY, a robotlike electronic simulator (developed by the author) that reproduces condylar movements previously recorded on a patient. Method and materials: The simulator consists of a custom-designed ultrasonic system that records mandibular movements in all three dimensions (vertical, horizontal, and coronal) with six degrees of freedom. The simulator automatically reproduces all movements around these axes with a robotic system with six stepper motors. The accuracy of the simulator was measured for all directions in space by registering eccentric jaw positions on both sides of 10 subjects in two ways: (1) by the ultrasound registration system; and (2) simultaneously with an interocclusal recording medium.The standard deviation and interquartile range of the differences between the measurements based on these two approaches were used to statistically describe the accuracy of ROSY. Results: The accuracy of the entire system was better than 0.28 mm. Conclusion: The electronic simulator comes with an accuracy that may render it suitable for clinical applications.

Accurate assessment of the location of the maxillary sinuses, incisive canal, and nasal cavity, as well as the height, width, and angulation of bone is essential for implant treatment planning. The purpose of this study was to introduce the clinical application of a cone-beam computerized tomography system (Ortho-CT) to assess multiple two-dimensional (2D) images for the preoperative treatment planning of maxillary implants. To evaluate the multiple 2D images scanned using the Ortho-CT system the maxillary region placed with radiopaque template in the maxilla. Ortho-CT images provided useful information for evaluating the morphology of the maxilla, for locating the incisive canal, maxillary sinuses, nasal cavity, and for showing the relationship of the template to the bone. It is concluded that the Ortho-CT system is a useful aid for diagnosis and treatment planning for maxillary implant treatment.

Noncarious, cervical, wedge-shaped, sclerotic lesions are commonly encountered in clinical practice. In such lesions, dentin has been pathologically altered, often resulting in partial or complete obliteration of the dentinal tubules. These lesions are known to respond to etching and bonding differently from normal dentin, leading to complications during clinical treatment. A search of the literature was performed to obtain background information on the most commonly cited etiologic factors, clinical diagnoses, and morphologic and chemical characterizations along with an extensive review of all potential obstacles to bonding the most recent adhesives to such a dentinal substrate. Recent progress in adaptive strategies to render dentin more receptive to resin bonding is emphasized in this article, and the major drawbacks of these strategies are discussed.

Objectives: The aim of this in vitro study was to investigate whether dentin is exposed during tooth preparation for resin-bonded fixed partial dentures and, if so, to quantify the amount of dentin exposure. Method and materials: Twenty extracted premolars were prepared in the following manner: The palatolingual and proximal axial surfaces were reduced by 0.50 mm. Mesial and distal grooves, 1.00 mm in depth, and mesial and distal occlusal rest seats, measuring 2.00 mm buccolingually × 1.50 mm mesiodistally × 1.00 mm deep, were prepared. The specimens were stained with a modified van Gieson's stain to identify dentin exposure, mounted on a jig to allow standardization, and photographed after 30-degree rotation to create a panoramic image of each tooth. The image was modified and analyzed to measure the percentage of the preparation area that exhibited dentin exposure. Results: Dentin exposure was noted in all specimens. The mean area of dentin exposure was 11.06 mm² (16.15% of the preparation area). The minimum and maximum areas of dentin exposure were 4.07 mm² (7.03%) and 19.73 mm2 (27.28%), respectively. Conclusion: Dentin is exposed during resin-bonded fixed partial denture preparation if current tooth preparation guidelines are followed, despite the commonly made recommendation that the preparation remain within enamel. The region of the grooves consistently exhibited exposed dentin; exposure at the cervical margin was variable.

This article describes the rationale and method of using glass fibers reinforced with resin composite as an external framework to reuse a patient's own natural anterior tooth as a pontic, after extraction.

Objectives: The purpose of this study was to address the prevalence of dental fusion and gemination in a sample of Jordanian dental patients. Frequency distributions of these conditions among different types of teeth are also presented. Method and materials: The data were collected from examination of radiographs from a random sample of periapical films. In all, 9,373 teeth from 1,660 dental records at the Faculty of Dentistry, Irbid, Jordan, were evaluated. A tooth was recorded having gemination if its crown was enlarged with a normal root and the tooth count was normal. A tooth was recorded fused if the tooth crown and root were enlarged and the tooth count revealed a missing tooth. Results: Fusion and gemination were detected in 18 and 21 teeth, respectively, with prevalence of 0.19% and 0.22%, respectively. Therefore, double teeth were found in 39 teeth with a prevalence of 0.42%. Maxillary central incisors were the most commonly affected (3.6%), followed by mandibular third molars (0.9%). Conclusion: Fusion and gemination are uncommon conditions, but they are important dental anomalies that could affect any tooth in the mouth. Recognizing the condition will facilitate the endodontic, prosthodontic, periodontic, orthodontic, and surgical clinical management of such teeth.

Objectives: Since the highly alkaline pH of calcium hydroxide is considered by many to be responsible for its biologic activity, the possible variations of pH induced by the different calcium hydroxide liners are accepted as a major concern. The aim of the present study was to determine the pH changes of five different calcium hydroxide liners and variations of pH levels at different time intervals. Method and materials: The materials tested were Dycal, Life, Calic, Dycal VLC, and Calcident 450. Samples were prepared according to manufacturer instructions and by using plastic molds; five standard samples from each material were prepared. The samples were then placed in separate vials, containing 10 mL deionized water (pH 7.0), and stored at room temperature (20°C). The pH measurements were taken 1 hour, 24 hours, 3 days, and 7 days after mixing. The pH variations of each material at the given time intervals were recorded, and the means were calculated. Results: Statistical analysis showed significantly high differences between the mean pH values induced by each material at all time intervals. The highest value for the first-hour measurement was for Dycal VLC, and the highest values for the other time intervals were for Calcident 450. The pH values of the materials exhibited statistically significant differences among all the time intervals. Conclusion: All materials changed the pH of deionized water toward alkaline.

b>Objective: The aim of this study was to test the effectiveness of a newly developed system, using masking noises with specific frequencies and amplitudes, adjusted to typical noises experienced during dental treatment such as the high-speed hand-held drill. Method and materials: In accordance with an analysis of typical noises experienced during dental treatment, masking noises with specific frequencies (frequency range 0.02 to 20 kHz) and amplitudes were created, with the aim of reducing the patients' awareness of typical treatment noises by overlaying frequencies. Two hundred fifty-four outpatients (113 males, 141 females) with a mean age of 32 years (± 10.5 years) were enrolled in this study. Patients were treated 15 minutes with and 15 minutes without the masking noise. Patients and practitioners filled out questionnaires aimed to evaluate the effectiveness of the system, sensitivity to noise (scale 0 to 10; 0 = effective, 10 = noneffective), psychologic aspects, and statements of fear. Results: There was a significant reduction in patients' awareness of noise using this system during dental treatment. Most of the patients regarded the masking noise as a pleasureable supplementation to common treatment and would select this manner of dental treatment employing the device again (81.5%); 48.2% said they were more relaxed. The system does not, in principle, interfere with dental treatment, and in most instances, the device does not impede the communication between practitioners and patients. Conclusion: The present study demonstrates that using masking noises during dental treatment reduces the sensitivity to drill noise, reduces fear and stress, and may be useful in dental practice as an adjunct to common dental treatment.

Fanconi anemia (FA) is a rare autosomal recessive disorder, characterized by pancytopenia and progressive hypoplasia of the bone marrow. A 23-year-old woman with FA showed severe pancytopenia and developed an abscess on the infraorbicular region on the right side of the face that progressed to phlegmon and caused tissue necrosis of the nostrils, nasal septum, nasal fossa, and posterior orbital region. Laboratory examination showed Streptococcus parasanguis as the etiologic agent of the phlegmon. Supportive treatment was recommended due to donor incompatibility for bone marrow transplant. The intraoral examination showed spontaneous gingival bleeding, edema of the interdental papillae, hematomas on the superior and inferior lips, bacterial and fungal infections, and adequate oral hygiene. The patient was treated with the administration of an antibiotic (imipenem), an antifungal (amphotericin B), and mouth washing with antiseptic solutions. Periodontal prophylaxis and orientation to and control of oral hygiene and diet were also used during the remission period. For functional and esthetic rehabilitation of the alar regions and nasal dorsum, an acrylic resin nasal prosthesis was made, supported by a spectacle frame.

Sixty cases of salivary gland tumors were diagnosed in the Oral Pathology Department, Faculty of Dentistry, Mahidol University, Bangkok, Thailand, from 1973 to 2002. Fifty-two cases (86.7%) involved the intraoral minor salivary glands, six cases (10%) were found in the major glands, and two cases (3.3%) were intrabony. The predominance of malignant over benign tumors was evident with 68.3% being malignant and 31.7% benign. Patients ranged in age from 9 to 75 years. The female to male ratio of benign intraoral salivary gland tumors was 1.4 to 1 and of malignant types was 1.1 to 1. The principle site of occurrence was the palate (65.4%), followed by buccal mucosa (13.5%). Pleomorphic adenoma (30%) was the most common benign tumor, and mucoepidermoid carcinoma (44.3%) was the most common malignant tumor. Comparing the data from the present study with other series, some discrepancies exist.

An asymptomatic case in which severe hypodontia and mandibular ectopic impacted teeth in the coronoid processes are visualized through panoramic radiographs, is presented.

Hyalinosis cutis et mucosae (lipoid proteinosis, Urbach-Wiethe disease) is a rare syndrome with autosomal recessive inheritance. The disease is characterized by diffuse deposition of a hyalinelike substance in the dermis, submucosal connective tissue, and various internal organs. In this study, the patient demonstrated classic signs and symptoms of lipoid proteinosis except for gingival infiltration. Gingival infiltration is still an unexplainable feature of this disease. In the context of this case, the diagnostic significance of the microscopic findings of the gingival tissues and the possible factors playing a role in gingival hypertrophy, are discussed.