Periodontal Therapy Evaluation

Periodontal Therapy Evaluation Chapter One: Introduction The objectives of periodontal therapy as stated by the American Academy of Periodontology official guidelines are natural dentition preservation; periodontal health maintenance and improvement, comfort, esthetics, and function; and replacements provision where indicated. (Guidelines for periodontal therapy .J Periodontol 1998) Therefore, the reduction of bacterial deposits and calculus on tooth surface is one of the objectives of periodontal therapy. (Axelsson et al, 1991) This objective can be achieved with hand scalers and curettes or ultrasonic scaling instruments. (Drisko, 1998) Many clinical studies showed no difference between ultrasonic/sonic and manual procedures when treating chronic periodontitis. (Tunkel et al, 2002) Total removal of subgingival calculus with hand or ultrasonic instruments or even periodontal surgery is not possible even with periodontal surgery. (Buchanan et al., 1987; Kepic et al., 1990). While Aleo et al. (1974) demonstrated the presence of bacterial endotoxins on diseased roots; Hatfield Baumhammers (1971) first described the cytotoxic effect of diseased root surfaces in cell cultures. The former workers also detected that human gingival fibroblasts did not adhere in vitro to a root surface contaminated with LPS in 1975. Therefore, it was determined that the removal of the affected cementum was critical to the success of periodontal therapy. Nakib et al. (1982), however, in another in vitro study failed to demonstrate penetration of endotoxins into root cement of either periodontally healthy or diseased teeth. As a result, they considered intended excessive removal of cementum was not acceptable in treatment, which was reinforced by other workers findings. Also Eide et al. (1983, 1984) found that the thin cuticle seen on diseased root surfaces that was most likely stemmed from the inflammatory exudate and could mineralize so these cytotoxic substances can be incorporated. Hughes Smales (1986) and Hughes et al. (1988) also did not approve the removal of substantial amounts of cementum, as LPS was detected by immunohistochemical techniques only on the cementum surface. Interestingly, Moore et al. (1986) demonstrated that virtually all the LPS associated with periodontally involved root surfaces could be removed just by rinsing and brushing. The root cementum has been studied for the presence of endotoxins as well as bacteria themselves. Hence for example Daly et al. (1982) observed in a histological study stainable bacteria in the cementum. They have showed that for a root surface to be free of contamination, cementum must be removed. Bacteria were also detected by Adriaens et al. (1988) in both the cementum and within the dentinal tubules. These authors as a result suggested the administration of chemotherapeutics to mechanical therapy in the treatment of periodontitis was required. Schroeder Rateitschak-Pliiss (1983) sanctioned the findings of Daly et al. (1982) of resorption lacimae in the cementum showing defects of 30-80 /im in depth. Likewise they found that extensive root planing was essential to remove bacterial accumulation niches. From a clinical point of view the motive for the extensive removal of root surface material has been questioned recently. Nyman et al. (1986) disclosed in beagle dogs that for an effective treatment of periodontitis the removal of so-called diseased cementum was not needed. The roots, following flap elevation, were instrumented with curettes and a diamond bur on one side of the jaw and on the contralateral side were only cleaned with interdental rubber tips and rubber cups by means of a low abrasive polishing paste. The healing, which was assessed histometrically, was alike with both treatments and was distinguished by a junctional epithelium with subjacent non-inflamed connective tissue. Nyman et al. (1988) in a subsequent study in humans, compared results in which the root surface polishing was accompanied by calculus removal but not cementum and similar healing was again seen. Blomlof et al. (1987), in another investigation on monkeys, found new attachment to the teeth treated with detergents rather than scaling. The effects of root scaling in an in vitro model system (Lie Meyer 1977) have been studied using SEM methods and limited to semi-quantitative assessments with the Loss of Tooth Substance Index (LTSI) score. Others have tried to determine the loss of substance from the micrometer screw recordings in the light microscope, after focusing twice (Allen Rhoads 1963). The ultrasonic instrument, in a corresponding in vitro model, caused loss of tooth substance of about 250 pm and of about 50 /im after the curette use. Berkstein et al. (1987) measured the diameter of the dental root with a micrometer caliper before and after single treatment with the curette, detecting a loss of substance of about 27 pxn. The effectiveness of the procedures of root planing can be studied in two different ways. The first one, In vivo studies, by evaluating healing of tissues around the treated teeth, and the other one, in vitro studies, directly following extraction of teeth after SRP in order to observe the characteristics and cleanliness of the root planed surfaces (Kepic et al, 1990). The stereomicroscope has been used by many authors to assess the residual calculus after extraction of the root planed teeth. However, to achieve a precise study to accurately evaluate root planed surfaces, scanning electron microscope (SEM) is a prerequisite (Rateitschak-Plà ¼ss et al, 1992). Many studies, concerning both microbiological and clinical aspects, have reported beneficial results from mechanical therapy (O’ Leary et al 1986; Ash et al, 1964; Sbordone, 1990). The hand instruments, ever since, were the first choice of clinicians. These instruments believed to produce a smooth root surface; yet, considerable manual dexterity is essential for their effective operation. Also, they are so time consuming and do not have the capability of reaching deeper root surface where pockets are more than 4 mm deep (Waerhaug, 1978; Rabbani et al, 1981 ). Ultrasonic tips were formerly designed for gross scaling and supragingival calculus and stains removal. Currently, modifications have been made to these power driven instruments to have longer working lengths and smaller diameter tips, thus providing better access to deep probing sites and more effective subgingival instrumentation. Ultrasonic instruments are easy to use; yet, it is often challenging to achieve a smooth and calculus free root surface (Moskow, 1972; Jones, 1972). Studies assessing variations in the magnitude of root surface changes created by hand, sonic, and ultrasonic instruments are lacking (Walmsley et al, 2008; Oda et al, 2004; Kocher et al, 2002). Bearing in mind manual and ultrasonic scalers, some reports show that manual scalers remove more root substance (Jacobson et al, 1994), while others showed that ultrasonic scalers do so (Oda et al, 2004). Concurrently, roughness of root surface after instrumentation is one of the most described changes in the literature. The relationship between the design of the tip, applied force, angulations and ultrasonic scaler type has been reviewed and all of these variables appear to explain the roughness of instrumented root surfaces (Flemmig et al, 1998). Ribeiro et al (2006) revealed that scaling with universal ultrasonic tips and diamond-coated sonic produced similar root surface roughness, which was more than that produced by hand curettes. Furthermore, another study by (Casarin et al, 2006) showed a positive influence of the ultrasonic scaler power settings on the roughness of the surface after instrumentation. As reported by those authors, more increased roughness was noted with greater settings of power. Lie and Leknes (1985) assessed the variations produced at different power settings by means of a subjective and controversial method, the Roughness Loss of Tooth Substance Index (RLTSI). The RLTSI assesses roughness and substance loss concurrently. Nevertheless, the loss of tooth substance with the use of a specific instrument cannot be straightway correlated with the root surface roughness (Kocher, 2002; Schmidlin et al, 2001), requiring a separate evaluation (Schmidlin et al, 2001).