The document summarizes the vascularity and innervation of the periodontal ligament (PDL). The PDL receives its main blood supply from the alveolar bone and branches from the apical and gingival vessels. It discusses the arterial supply and distribution of vessels in the PDL. Orthodontic tooth movement is described as a pathological process that involves pressure and tension areas around the tooth, leading to changes in the PDL thickness and vascularity. The innervation of the PDL is outlined, including the types of neural terminations. Periodontitis is characterized by gum inflammation, deep pockets, and loose teeth from loss of tissue and bone. The use of lasers in periodontal therapy is discussed, noting
1. بسم الله الرحمن الرحيمVascularity and Innervation of the PDL ByFatemah Mahmoud Oraby(208)
2. Topics to be discussed: Vascularity of the PDL Orthodontic movement Innervation of the PDL Periodontitis Laser Therapy
3. The Periodontal Ligament Is a thin, fibrous ligament that connects the tooth to the bony socket. Normally, teeth do not contact the bone directly; a tooth is suspended in its socket by the fibers of the ligament. This arrangement allows each tooth limited individual movement. The fibers act as shock absorbers to cushion the force of the chewing impact of mastication.
4.
5. PDL Vascularity The PDL receives its main blood supply through vessels that enter the PDL space through the alveolar bone, but it also receives contributions from the apical and gingival vessels. The main blood vessels within the PDL course are parallel to the long axis of the tooth and run between the collagen fiber bundles near the alveolar bone. Many arterio-venous anastomoses occur in the ligament, particularly in the apical and alveolar crest regions.
6.
7. Arterial Supply of the PDL 1. Branches from the apical vessels supplying the pulp. 2. Branches from intra-alveolar vessels penetrating the alveolar bone. 3.branches from gingival vessels entering from a coronal direction.
11. They are more abundant in the mandibular posterior teeth than maxillary and anterior teeth.
12.
13. Interstitial Areas Are located between the bundles of principal fibers. They contain finer collagen fibers termed interstitial fibers which support blood vessels, nerves and lymphatics.
14. Interstitial space
15. In addition to the constituents of the interstitial areas, observe the Volkmann's canal of the alveolar bone and the epithelial rests of the periodontal ligament.
16.
17.
18.
19.
20. A marked increase in the vascularity of PDL due to increase in capillary blood supply.
21. This helps in mobilization of fibroblasts and osteoclasts(bone resorbing cells that lie in Howship’s lacunae).
27. 3.There are four types of neural terminations in the PDL that have been described: 1- Free endings 2- Ruffini’s Corpuscles 3- Tactile (meissner’s) corpuscles 4- Spindle type nerve endings
28. Periodontitis Characterized by the following: Gum inflammation, with redness and bleeding Deep pockets (greater than 3 mm in depth) that form between the gum and the tooth Loose teeth, caused by loss of connective tissue structures and bone
29.
30. The Use of Lasers in Periodontal Therapy Laser optical fiber is significantly thinner and therefore less invasive than most hand instruments. Patients can resume their daily activities including eating immediately after treatment. Each pulse of light vaporizes a specific number of cell layers within the area of the beam. Laser periodontal therapy removes only the diseased tissue without removing any healthy tissue.
31.
32.
33. Advantages Maintains the height of tissue around the teeth Minimizes Minimizes bleeding Minimizes discomfort to healing time the patient
34. Disadvantages Each laser has different wavelengths and power levels that can be used safely during different periodontal procedures. Damage to periodontal tissues can result if an inappropriate wavelength and/or power level is used during a periodontal procedure.
