A post on bruxism (part 3)

From Contemporary oral medicine 2019

Signs of SB:

-Tooth wear: Erosion most commonly causes excessive tooth wear with attrition following closely. Attrition can be charaterised by flat planes on teeth i.e wear facets, with planar enamel wear and shallow dentine wear with well defined margins in the enamel of incisal edges or with step like areas on the palatal aspects and equivalent facets on all opposing teeth. In contrast, erosion tends to damage dentine more deeply causing cupped lesions and loss of surface anatomy. Bed partner or parent reports of tooth grinding sounds can also be helpful in diagnosis.
-Masseter hypertrophy: This is a benign, asymptomatic enlargement of one or both masseter muscles. There is a slight male predominance with an average age of 30 years.
-Tongue indentation (Tongue scalloping): This has been associated with bruxism, more commonly clenching. It has been suggested that Tongue indentations may be caused by macroglossia secondary to systemic amyloid disease
-Linea alba: present on the buccal mucosa in line with the occlusal plane is a well defined white line. This is always bilateral and is considered to be a hyperkeratinisation of the buccal mucosal epithelium. it may be more common in women than men. Linea alba may be caused by the suction effect of teeth against buccal mucosa.
-Fractures: Nocturnal bite foce during SB can exceed the maximal day voluntary clenching force. This can cause fractures to teeth and restorations
-Tori and exostoses: Asymptomatic bony outgrowths that can occur unilaterally or bilaterally in either jaw. The assumption is that patients with bruxism have heavier muscle forces which causes bone reinforcement however this assumption has been highly controversial.
-Dental pulp alterations: Occlusal trauma can initiate degenerative or inflammatory processes that affect pulp health. This can result in hypersencitivity, inflammation, atrophy, necrosis, calcification and dentinal sclerosis.
-Progressive dental crowding: Generated force through tooth clenching is transmitted forwards through the contact points known as the anterior component of forces. This increases in proportion to tooth clenching forces. There is a positive relationship between these forces and dental crowding.

Symptoms of SB:
-TMD: It is believed that there is a close relationship between SB, pain and TMD however the evidence is mixed. When TMD patients awake with pain they often attribute pain to SB activity. However sleep lab studies have shown no association between SB and pain intensity.
-Headache: Morning headache doesn't seem to be associated with the severity of SB. Those with lower SB events per hour displayed more morning headache than those with moderate to severe bruxism. Headaches may be more related to sleep alterations e.g insomnia, respiratory disorders and leg movements. Clinicians should first exclude the presence of SDB before making assumptions that the headache is related to SB.
-Tooth pain and mobility: It is common for patients to complain of mobility and tooth pain on awakening. This originates from heavy forces generated on teeth which widens the PDL causing pain and increased mobility.