The gums or gingiva is subdivided into the free gingiva and the fixed gingiva.
- The free or marginal gingiva lies against the element on the inside and thus forms the sulcus gingivalis. The depth of this sulcus is 0.5-3 mm with healthy gums. This can be measured with a pocket probe. On the outside, the free gingiva runs from the gingival edge to the gingival quarry. That is what the fixed gingiva is about (see image below).
- The fixed or attachingiva is partially attached to the teeth with fibers and the epithelial attachment. The other part is the associated with the alveolaris processus. The attachment with fibers can be seen buccally as a dot of the fixed gingiva. The fixed gingiva width varies from 1-9 mm and is visible as a pale band. Due to racial pigmentation, it can sometimes be a bit darker (see image below).
- Between the elements we see the interdental papilla, which fills the approximal space between two adjacent teeth or molars.
- The alveolar mucosa starts at the edge of the fixed gingiva and merges buccally into the fold fold and linguistically into the soft tissue of the mouth. Palatinaal there is not really an alveolar mucosa: here the permanent gingiva passes into the mucosa of the palatum. The color of the mucosa is red due to the good blood circulation. The surface is glossy smooth and not dotted (see image below).
Root cement is the calcified tissue that covers the root. This contains the fibers of the periodontal ligament attached. There is cellular and acellular cement. Cementoblasts are found in cellular cement: cells that can produce new cement. This cement mainly occurs on the apical part of the root. Acellular cement (cement without cementoblasts) mainly occurs on the coronal part of the root.
Normally the cement runs up to the enamel, or slightly over it. We call the transition from glaze to cement the glaze-cement limit. It is a clearly visible and palpable line on a dental element.
The part of the mandibula or maxilla in which the alveols (dental greenhouses) are located is called the alveolaris process. The alveolar bone consists of two cortical bone plates of compact bone, which are buccal and lingual (palatal), with in between:
- Spongy bone, which contains the bone marrow and which is made up of bone bars;
- Lamina cribrosa around the alveole. This is a thickened layer of fiber leg, which is perforated. The ends of the Sharpey fibers are attached here.
The shape of the alveolar bone edge is determined by:
- The course of the glaze and the glaze-cement boundary;
- The location of the element in relation to the neighboring elements; and
- The degree of eruption (the extent to which the element has broken through) (see image below).
The root membrane, periodontal ligament, consists of connective tissue ligaments, which hold the tooth in the dental socket (alveole). The root membrane, together with the root cement and the alveolar process, have the following functions:
- Physical function. The forces exerted on the element are absorbed as with a shock absorber; the forces are also partially transmitted to the bone. Furthermore, the root membrane ensures the attachment of the element in the bone and the protection of blood vessels and nerves.
- Formative function. In the periodontal ligament, there are cementoblasts that produce cement. Furthermore, the ligament contains periodontal osteoblasts and osteoclasts, which respectively make and break down bone.
- Nourishing function. The blood vessels present provide the necessary building materials to the cement, bone and gingiva.
- Sensory function. The nerve supply ensures the registration and regulation of the chewing pressure: the feeling.