Relationship between symptoms and relevant literature review

Symptoms of Periodontitis

Smoking and periodontitis

Diabetes and periodontitis

Diagnosis of periodontitis

Types of probes

Probing force and probe diameter

Histopathological alteration in the periodontal tissues

Bleeding on probing (BOP) refers to bleeding of the gums induced by gentle manipulation of the tissue at the depth of the gingival sulcus or at the interface between the gingival and a tooth. This is frequently accomplished by the use of a periodontal probe. BOP is a sign of inflammation of the gums and is indicative of some sort of destruction and erosion to the lining of the sulcus.

Periodontal disease is a set of inflammatory diseases usually affecting the tissues that surround and support the teeth otherwise called periodontium. This disease involves progressive loss of the alveolar bone around the teeth, and without treatment it can lead to loosening and possible eventual loss of teeth. Periodontitis is caused by microorganisms adhering and growing on the tooth surface, along with an overly aggressive immune response against this microorganism. The diagnosis is through inspecting the soft gum tissues around the teeth with a probe and x-ray films and visual analysis to determine the amount of bone loss around the teeth (Lang & Tonetti, 1996).

The cause of gingivitis is poor oral hygiene leading to the accumulation of mycotic and bacterial matrix at the gum line, called dental plaque. Other causes are poor nutrition and underlying medical problem such as diabetes. Finger nick tests have been approved to identify and screen patients for possible contributory causes of gum disease such as diabetes. In a number of patients, gingivitis worsens into to periodontitis. This comes about as a result of destruction of the gingival fibers; the gum tissues separate from the tooth and deepened sulcus. Sub-gingival microorganisms colonize the periodontal pockets causing advanced inflammation in the gum tissues and progressive bone loss.

Another strong risk factor that could predispose one periodontitis is one's genetic susceptibility. Several conditions and diseases, such as diabetes, Down syndrome and other diseases affecting one's resistance to infection increase susceptibility to periodontitis. Another factor making periodontitis a difficult disease to study is that human host response can also affect the alveolar bone resorption. Host response to the bacteria is mainly determined by genetics, however, immune development may play a role in susceptibility (Heins & Karpinia, 1998).

1.1 Symptoms of Periodotitis

Periodontitis has very few symptoms in early stages and in many individuals it goes undetected till it has significantly progressed and that is when they seek treatment.

Symptoms include redness or bleeding of gums while brushing teeth or biting into hard food, gum swelling that recurs, halitosis and a persistent metallic taste in the mouth. Also gingival recession, causing apparent lengthening of teeth, deep pockets between the teeth and the gums and loose teeth, in the later stages. However, gingival inflammation and bone destruction are painless; hence, most patients assume that painless bleeding after teeth cleaning is insignificant, although this may be a symptom of progressing periodontitis.

Periodontitis is associated to increased inflammation in the body indicated by raised levels of C-reactive protein and Interleukin-6 which increases the risk of stroke myocardial infarction and atherosclerosis. It also associated to those over 60 years of age to impairments in delayed memory and calculation abilities. (Heins & Karpinia,1998).

1.2 Smoking and periodontitis.

Cigarette smoking has been highly associated with impaired healing of surgical wounds and related to periodontitis. (Silverstein et al., 2000). The harmful effects of cigarette smoking on the periodontal status have also been well-documented. The adverse effect of smoking in implants has been described in a study of the outcome of 2,194 implants placed in 540 subjects. The study showed that a considerably higher percentage of implant failures occurred in smokers than in non-smokers. Smokers had total implant failure rate of 11.3%, and only 4.8% of the implants failure rate in non-smokers (Chaves et al., 1993).

However, limited information exists with consideration of the consistently natural occurring plaque and bleeding on probing in the oral cavity under normal oral hygiene measures. The study was to explain the distribution of tooth surfaces covered by supragingival plaque and gingival units bleeding on probing in a steady state environment of no dental interference. Also relative consistency of plaque and bleeding was studied. 65 volunteers, 14 women and 51 men ranging from the age of 19 to 30 years, participated. 33 volunteers were heavy smokers and 32 non-smokers.

Clinical examinations discovered mild, plaque-induced gingivitis without clear destructive periodontitis. Within a 6-month period, occurrence and amount of plaque, calculus and gingival bleeding was site-specifically examined four times. Well-defined, symmetric and regular patterns of plaque and calculus distribution in the oral cavity were observed, which were rather the same in smokers and non-smokers. It is worth noting that smokers had uniformly more plaque in all regions of the oral cavity as compared to non-smokers.

In contrast, there was no obvious pattern of bleeding on probing. Stability of observations was considerably less than for plaque scores and it was particularly true for smokers, where the relationship between bleeding scores was smaller than in non-smokers. A large part of the difference in gingival bleeding may be due to presently unknown factors other than plaque and calculus with extensive consequences for preventive program (Lang et al., 2001).

1.3 Diabetes and periodontitis

Another risk factor for periodontitis is uncontrolled diabetes. So far, facts related to disease-free implant survival in diabetics is still preliminary. A one-year report of implant survival in Type II diabetics showed a 7.3% failure rate. This shows that osseointegration can be obtained in the most diabetic patients. However, the standard of a long-term prognosis of implants placed in these subjects is presently unknown.

1.6 Probing force and probe diameter

The relationship between bleeding on probing, probing force and probe diameter is usually determined by the pressure exerted on the gingival tissues and resistance from the healthy or inflamed tissue. This pressure is directly proportional to the force on the probe and inversely proportional to the probe tip diameter. Large probing diameters reduce probe progress into inflamed connective tissue hence this effect of change in probe diameter reduces the pressure in a greater manner than an increase of similar change in probe force.

According to the research conducted by Silverstein et al., (2000), the pressure used to place the probe tip at the base of the periodontal sulcus is approximately 50 N/cm2 and at the base of the junction epithelium is 200 N/cm2. A tip diameter of 0.6 mm is needed to reach the base of the sulcus. Clinical inflammation does not reflect the severity of histological inflammation, and the recordings may not illustrate probing depth. Therefore, probing depth does not identify anatomical locations at the base of the sulcus. Probe tips must have a diameter of 0.6 mm and a 0.20 gram force (50 N/cm2) to gain a pressure which demonstrates estimated probing depth. This pressure is useful for the measurement of the reduction of clinical probing depth, which includes the formation of a long junctional epithelium as a result of treatment. but, different forces or diameter tips are essential for the measurement of healthy or inflamed histological periodontal probing depths.

A research was done to establish whether probing force had an influence on the amount of clinical attachment-gain assessed after treatment by scaling and root planing. A probing device was constructed which permitted concurrent monitoring of probing force and probe penetration and which standardized the insertion pathway for recurring measurements. In 10 periodontal patients, 2 deep pockets were selected then measured before and after periodontal treatment by scaling and root-planing. Depth-force plots were compared by superimposition. Depth values were determined at 5 different force levels (0.25, 0.50, 0.75, 1.00 and 1.25 N) on every plot and changes of clinical attachment levels were calculated. A major relationship was seen between probing force and attachment level.

The values obtained with 0.25 N. were extensively different from the values obtained with higher forces (p < 0.001). Minor, but non-significant differences were noted in the amount of attachment-gain obtained at the 5 force levels. At a probing force level of 0.25 N, there was 0.80mm mean attachment gain. With 0.50 N, there was a gain of 0.70mm; with 0.75 N. The gain amounted to 0.67 mm in mean. At 1.00 N. And at 1.25 N, a gain of 0.66 mm was recorded. (Fowler et al., 1982)

The present research to determine the threshold pressure value to be applied in provoking bleeding on probing in clinically healthy gingival units. Regression study revealed an almost linear association and a high connection coefficient between bleeding on probing and probing force. The result demonstrated that the bleeding on probing test using uncontrolled forces may result in a part of false positive readings and a strong possibility exists for the traumatizing of clinically healthy gingival tissues if a probing force exceeding 0.25N is applied (Lang et al., 1990)

Bleeding on probing and gingival index is clinically used to characterize the extent of gingival inflammation. However, it is not clear to what level these parameters correlate to each other and to probing pocket depth. This study was to evaluate the relationship between bleeding on probing and gastrointestinal bleeding (scores of 2 and 3), as well as the relationship of these variables to probing depth, in a group of patients presenting with naturally-occurring gingivitis. Based on screening examinations of 125 patients with at least 20 teeth, at most 4 sites with probing depth over 6mm a bleeding on probing frequency of 30% or more, and no systemic condition that would influence the inflammatory response, were selected. Two weeks after screening patients were examined at 6 sites per tooth for plaque index, gastrointestinal bleeding, probing depth and bleeding on probing.

A standardized pressure sensitive probe (Florida Probe) with 20g probing force was used for bleeding on probing and probing depth measurements. Means of 40.9% (S.E. = 1.36) bleeding on probing sites and 35.3% (S.E. = 1.81) gastrointestinal bleeding sites per patient were found. A total of 20,008 sites ranging in probing depth up to 5.9mm were evaluated, though, most sites (19,723, 98.6%) presented with < 4 mm probing depth. When sites were evaluated, bleeding on probing confirmed a positive correlation with probing depth, whereas gastrointestinal bleeding correlated with probing depth. For sites characterized by the absence of bleeding on probing and gastrointestinal bleeding (scores 0 and 1), the highest percentage of union between the 2 indices (77.7%) was found in shallow sites (0.1-2 mm) index (Chaves, 1993).

Another study showed that the bleeding on probing test using uncontrolled forces may result in an amount of false positive readings when used as a parameter for inflammation. A strong likelihood exists for the traumatizing of clinically healthy gingival tissues if a probing force exceeding 0.25 N. is applied. The aim was to evaluate the relationship between probing pressures and gingival conditions in patients with a history of treated periodontal disease. 10 patients enrolled in a periodontal maintenance program after treatment of moderate to advanced chronic inflammatory periodontal disease were used. They were chosen on the basis of a record of excellent oral hygiene practices for at least 2-6 years and nearly complete absence of clinical inflammation after successful periodontal therapy.

Probing force of 0.125, 0.25, 0.375 and 0.5 N. was applied in the 4 jaw quadrants at 2 different occasions with an interval of 10 days, then bleeding on probing was assessed. Oral hygiene and gingival conditions were determined using the criteria of the plaque and gingival index systems. All patients showed major increases in mean bleeding on probing percentage with increasing probing force applied (2.5%-7.9%). Regression analysis discovered an almost linear relationship and a major correlation coefficient between bleeding on probing and probing force. Almost identical slope inclinations were found when the 6 patients with the lowest mean bleeding on probing at 0.25 N. were compared with the regression analysis of the whole group (Karayiannis, 1992).

A research was done to assess the bleeding on probing tendency and periodontal probe penetration when various probing forces were applied at implant sites in patients with a high standard of oral hygiene with well-maintained peri-implant tissues. 17 healthy patients with superb oral hygiene in a maintenance program treatment for periodontitis were recruited. Their missing teeth had been replaced using oral implants. The bleeding on probing and probing depth was assessed at the mid-buccal, mid-oral, mesial and distal aspects of the buccal surfaces of every implant. Contra-lateral teeth were designated and assessed for bleeding on probing and probing depth in the same locations and at the same observation visits.

At every visit, implants and contra-lateral teeth were at random assigned to one of the standardized probing forces (0.15 or 0.25 N). The second probing force was applied at the repetition of the examination after 7 days. The results showed that increasing the probing pressure by 0.1 N. from 0.15 N. brings about an increase of bleeding on probing percentage by 13.7% for implants and 6.6% contra-lateral teeth. There was a significant difference of the mean bleeding on probing percentage at implant and tooth sites when a probing pressure of 0.25 N. was applied. A considerably deeper mean probing depth at implant sites compared with tooth sites was found regardless of the probing pressure applied. The results of the study showed that 0.15 N. might characterize the threshold pressure to be applied to avoid false positive bleeding on probing readings around oral implants. Therefore, probing around implants confirmed a higher sensitivity compared with probing around teeth. (Gerber et al., 2009).

1.7 Histopathological alteration in the periodontal tissues

A study about histopathological alteration in the periodontal tissues was designed and 22 patients were enrolled. Out of 22 patients, gingival tissue biopsies samples were obtained from active sites of 10 and 12 periodontal-healthy and periodontal disease, probing depths >5mm patients, respectively. The groups was again divided into 25 -- 50 and >50 years age subgroups.

The result showed a significant decrease in the appearance of Tumors Necrosis Factor Receptor-Associated Death Domain (TRADD). This was observed in 25 -- 50 years of periodontal disease group compared to the periodontal healthy group. BCL2-associated X protein expression in the periodontal disease group was considerably decreased in 25 -- 50 years age group but increased in the >50 years age group compared to periodontal healthy age groups. Periodontal disease patients of both 25 -- 50 years and >50 years age increased in the expression of Cytochrome C. And Caspase-3 compared to the respective periodontal healthy groups. The periodontal disease patients showed a stronger correlation with age in the expression of Tumors Necrosis Factor Receptor-Associated Death Domain and BCL2-associated X protein compared to the periodontal healthy groups. (Archives of Oral Biology)

Non-surgical periodontal therapy results in a great decrease of pocket probing depths and bleeding on probing, and attachment gain. When combined with periodontal maintenance a long-term stability of periodontal conditions, which shows a decreased incidence of extra attachment loss and reduction in bleeding on probing is possible and has been evidenced even in residual pockets with probing depths of greater than 7 mm. This data shows that significant changes in the immune/inflammatory response take place after treatment. Though, it is not clear, whether the clinical signs following periodontal therapy are related with an expression profile of inflammatory and immunological genes that is well-matched with periodontal health (Thomas et al., 2008).

It has been hypothesized that the histopathological changes linked with the application of biomechanical forces bacterial infection would act in two topographically separate areas that is the deeper bone-implant interface and the marginal peri-implant soft-tissue seal, respectively.

In a seminal animal study has experimentally shown that both ligature-induced infection and biomechanical overload may lead to clinical and histopathologic alterations of the tissue integration of dental implants. This study indicated that ligature-induced infection resulted in clinically evident loss in attachment level and marginal bone that were similar in magnitude. An infection exposed implant remained clinically immobile and such lack of clinically significant mobility associated with a high percentage of remaining direct bone-to-implant contact in the more apical portion of the implant.

Periodontal sites of shallow initial probing depth often seem to lose probing attachment after different types of periodontal therapy, surgical or non-surgical therapy. The susceptibility to this treatment-related loss of probing attachment may possibly be linked to gingival architecture as well as the inflammatory status of the tissues. This study was intended to show the relationship of buccolingual gingival thickness and bleeding on probing in shallow buccal sites (3.5mm probing depth) to probing attachment loss after nonsurgical therapy. Three months after treatment including oral hygiene instruction and supra- and sub-gingival debridement, thin (1.5mm), at first non-bleeding sites showed a mean loss of probing attachment of 0.3mm. Thick ( 2.0 mm), non-bleeding sites showed a less noticeable mean loss of probing attachment, as bleeding sites of both categories of gingival thickness showed a tendency towards gains in probing attachment levels.

1.8 Conclusion.

In conclusion, the mean loss in probing attachment levels, mostly seen for shallow sites post-therapy, may be widely due to the changes in shallow, thin healthy attachment areas. The histologic analysis of these lesions showed facts of an obvious supracrestal inflammatory infiltrate.

Implants exposed to bio-mechanical overload, usually presented a somehow distinct clinical, radiographic, and histologic picture. In this group of implants, a difference was noted between the degrees of attachment loss and that of bone loss, with greater amounts of bone loss observed. In addition, 75% of the implants displayed clinically evident mobility linked with sharp decreases in the percentages of direct implant-to-bone contact. Eventually it led to loss of two of the implants.

The histopathological appearance of a number of these lesions showed a complete substitution of the bone-to-implant contact with nonmineralized soft tissue. However, there was an observation that the epithelium never migrate apically past the implant shoulder. This has implied that it may be possible to lose osseointegration without losing clinical attachment areas. The histopathologic appearance of peri-implantitis and overload lesions also represents the basis for the clinical detection and differential diagnosis of the two syndromes. (Listgarten, 1980)

A recent research on the development of periimplantitis looked at the risk related with bleeding on controlled-force probing of peri-implant pockets. The results showed that absence of bleeding on probing had a 97% negative analytical value for continuing attachment loss over the 6-month experimental study period. The positive predictive value was much lower. This primary observation indicated that an absence of bleeding on probing may clinically functional predictor for strength of peri-implant attachment level. It is also dependable with current data on periodontitis, which show a 99% negative predictive value of bleeding on probing for progressive periodontitis but inadequate positive predictive value (Lang et al., 1986, 1990).

Generally, bleeding on probing as a symptom of periodontitis is influenced by probing force, probe depth or diameter and histological alterations to the periodontal tissues. Hence, this pressure is directly proportional to the force on the probe and inversely proportional to the probe tip diameter. A periodontal probe is an instrument used in the dental armamentarium. There is a major increase in mean bleeding on probing percentage with increasing probing force applied.

Non-surgical periodontal therapy results in a great decrease of pocket probing depths and bleeding on probing, and attachment gain. However, histological studies indicate that the gingival infiltrate linked with dental plaque is mostly characterized by a B cells and plasma cells. Periodontal tissues from sites with severe chronic periodontitis after periodontal therapy identifies genes involved in tissue homeostasis. The mean loss in probing attachment levels, mostly seen for shallow sites post-therapy, may be mainly due to the changes in shallow, thin healthy attachment areas. The histologic analysis of these lesions showed facts of an obvious supracrestal inflammatory infiltrate